The University of Texas Publication No. 4101 January 1, 1941 THE LARGER INVERTEBRATE FOSSILS OF THE NAVARRO GROUP OF TEXAS (Exclusive of Corals and Crustaceans and Exclusive of the Fauna of the Escondido Formatio1n) By LLOYD WILLIAM STEPHENSON Bureau of Economic Geology E. H. Sellards, Director Issued O.ctober, 1941 PUBLISHED BY THE UNIVERSITY OF TEXAS AUSTIN Publications of The University of Tesaa PUBLICATIONS COM:llITTB E. J. MATBEWS R.H.GRIFFITB C. F. ARROWOOD A. SCHAFFBB D. CONEY J. W. SPIES A. C. WRIGHT General Publications R. H. GRIFFITH H. R. HENZE LOUISE BAREKMAN A. SCHAFFER FREDERIC DUNCALF E.G. SMITH FREDERICK EBY G. W. STUMBERG Administrative Publications E. J. MATHEWS S. A. MACCORKLI C. F. ARROWOOD B. MCLAURIN C~ D. SIMMONS The University publishes bulletins four times a month, so numbered that the first two digits of the number show the year of issue and the last two the position in the yearlyseries. (For example, No. 4101 is the first publication of the year 1941.) 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THI UNIVERSITY OF TEXAS PR~S5 ..... The University of Texas Publication No. 4101: January 1, 1941 THE LARGER INVERTEBRATE FOSSILS OF THE NAVARRO GROUP OF TEXAS (Exclusive of Corals and Crustaceans and Exclusive of the Fauna of the Escondido Formation) By LLOYD WILLIAM STEPHENSON Bureau of Economic Geology E. H. Sellards, Director Issued October, 1941 PUBLISHED BY THE UNIVERSITY FOUR TIMES A MONTH AND ENTERED AS 81tC:OND·C:LAa MATTIER AT THE POST OFFIC:E AT AUSTIN, TEXAS, UNDSR THIE ACT OF AUGUST 24, 1912 The benefits of education and of useful knowledge, generally diffused through a· community, are essential to the preservation of a free govern· ment. Sam Houston Cultivated mind is the guardian genius of Democracy, and while guided and controlled by virtue, the noblest attribute of man. It is the only dictator that freemen acknowledge, and the only security which freemen desire. Mirabeau B. Lamar CONTENTS PAGE Jntroduction ____ _-------------------------------------__ -----------------___________________________________________________________________________________ _ 5 CJassification of the Navarro group ··-____________ ---------------------------------------··----------------------------------------_______ __ _ fi General features of the group -------------------------------------------------------------------------------------------------------------------R Ney1andvi11e marI _-----------------------------_ _______________________________________________________________________________________________________ _ 17 Definition ----------------------------------------------------___________________________________ -------------------___________________________________ _ 17 Analysis of the fauna --------------------------________________________ --------------------__ __ __________________ ----------------___________ _ 17 Correlation ______________ ____________ -------------__ ____ ·-----_________________ ------------------------------__________------------------------------19 Nacatoch sand ----------------------____________ ------___________________________________________________________ ------------________ .____________________ _ 20 Dcfinition ....______________ ----------------------________ ·-----_____________________ .__ -----------------------------------------------________________ 20 Analysis of the fauna ------------------------------------·-----------------------------------------------------------------------------------20 CorreIation ------------------------_________ .____________________________________________________ --------------------______________________------------22 Corsicana marl ----------------------------------------------------------------------------------------------------------------------------------------23 Definition ------------------------------------________________________________________________ -----------------------------------· _____________________ _ 23 Analysis of the fauna·-------------------------------·---------------------_______________ --------------------------------------------------24 Correlation ----------------------------------------------_·------------------__________________________________________________________ ._____________ _ 26 Kemp clay --------------------------------------____________________________________________________________________________________________________________ _ 27 Definition ________________________________________________________________________________________________________________.___________________________ _ 27 Analysis of the fauna -----------------------------------------------------------------·-----------------------------------------------------28 CorreIation --------------------------____________ .. ______________________________ ._______________ ...__________________________ ._______________________ _ 29 Analysis of the Navarro fauna as a whole --------·--------------·----------------------------------------------------------------·-­30 Marine equivalents of the Navarro in western United States ·-----·-----------------·-------·-----------------------­33 Marine equivalents of the Navarro group outside the United States -------------------------------------------···-­34 Navarro fossil localities in Texas-------------------------------------------------------------------------------·------------------------·----46 Fossils from the Neylandville marl--·---------------------------------·-----------------------------------------------------------­46 Fossils from the Nacatoch sand ---------------------------------------------------------------------------------------·-------------· 47 Fossils from the Corsicana marl ----------------------------------------------------------------------------------------------···----4btained from septanae lmbedded m blue and gray arenaceous clays." Although Shumard made several references to the Navarro beds he apparently had no in­kntion of formally proposing Navarro as the name of a geologic unit, for in no less than 16 of the Navarro County locality descriptions he ascribes the source of the fossils to the Ripley group, to which unit he obviously intended to refer the fossil­iferous beds in Navarro County. Navarro was first formally introduced as a unit name by Hill8 in 1887; in a tabular classification of the Cretaceous sediments of east-central Texas he applied the name Navarro beds to all the strata intervening between the "Dallas limestone" ( = Austin chalk) below and the basal Tertiary above; the Navarro unit therefore included the Exogyra ponderosa marl (=Taylor marl). In 1892 Hill• gave to the Exogyra pon­derosa marl the geographic name Taylor marl, thus by inference restricting the Navarro to the Cretaceous beds above that zone, which, however, he called the "Up­}'ermost or Glauconitic Division." Hill in ]90P applied the name Navarro forma­tion to the strata lying between the Taylor formation ( = Exogyra ponderosa marl) below and the Eocene (=Paleocene ac­cording to present classification) strata above, thus definitely restricting the name Navarro to the unit now known as the Na­varro group. In the same publication the names Corsicana beds and Kemp clay beds lAdk.in1, W. S., The Meaozoic systems in Texas: Univ. Teue Bull. 3232, Geology of Texa1, vol. l (Stratigraphy). pp. 480·481, 516, 1933. IShumard, 8. F .. Deacritions of new Cretaceous fo99ils from Teus: Boston Soc. Nat. Hist. Proc., vol. 8, pp. 188·205, 1861. *Hill, R. T., The Texas section of the American Cretaceou1: Am. Jour. Sci., 3d &er., vol. 33, p. 298, 1887. See also White, C. A., Acad. Nat. Sci. Philadelphia Proc., vol. 39, p. 40, 1887. •nm, R. T., Artelian inve1t:gations, 6nal report, pt. 3, pp. 73.74, 52d Congr., ht &e1e., Ex. Doc. 41, pt. 3, 1892. l5ffilJ, R. T., Geography and reolOIY of the Black and Grand prairie., Texas: U. S. Geol. Survey 21st Ann. Rept., pt. 7, pp. 338.345, 1901. were proposed as subdivisions of the Navarro formation in the area between North Sulphur River in Delta County, and Brazos River in Falls County. The strat­igraphic limits of these units were not 1·recisely defined, but the geographic dis­tribution given for the Corsicana beds indicates that this unit included in its up­per part the Corsicana marl (restricted) of the present report. Presumably the Kemp clay beds included the remainder of the Navarro to the base of the overlying Mid­way group of the Paleocene. The present usage of Kemp seems therefore to conform approximately to Hill's original usage. The belt of ountcrop of the Navarro group in Texas is shown in figure 1. The principal subdivisions of the Upper Cretaceous or Gulf series now recognized in east-central Texas are graphically shown in figure 2. The four subdivisions of the Navarro group in east-central Texas, indicated ahove, were suggested by me in a note quoted by Adkins ( 1933) , 6 and these names were adopted by the United States Geological Survey for the cooperative geo­logic map of Texas published in 1937, and for the Cretaceous correlation chart prepared by geologists of the United States Geological Survey, under the auspices of the National Research Council, in 1941.7 The name Nacatoch sand was first used by A. C. Veatch in 19058 for a marine sand formation in southwestern Arkansas, and the Nacatoch sand of Texas is the equiva­lent of the Arkansas unit. From Bexar County westward the Na­varro group is represented only by the Escondido formation, a unit which, though of the age of the Kemp clay, nevertheless possesses certain distinctive lithologic and faunal characteristics. The fauna of the Escondido is not included in the scope of the present monograph. 60p. cit., p. 516. 7Stephen1on, L. W .. King, P. B., Monroe, W. H., and Imlay, R. W., Correlation of the outcropping Cre'laceous formations of the Atlant:c 11nd Gulf Coastal Plain and Trans. Pecos Texas: Bull. Geol. Soc. Amer. (in press). 8Veatch, A. C., The underground waters of northern Louisiana and southern Arkansas: Louisiana Geol. Survey Bull. I, pp. 81, 85, 87-88, 1905. [Underground waters of] Lou'siana and southern Arkansas: U. S. Geol. Sun·ey Water-Supply Paper l U, pp. 180, 183, 1905. The University of Texas Publication No. 4101 Fig. 1. lap h win er th· lo pl tt d th ] ('Uliti GENERAL FEATURES OF THE GROUP The sediments composing the Navarro group were deposited in marine waters probably not exceeding 100 fathoms in depth, but for the most part deep enough ind x map on which are to escape disturbance by wave action. The materials consist mainly of massive or only feebly bedded marls, chalky marls, clays, and sands, with subordinate in· clurated, concretionary masses or layers cemented with calcium carbonate; cross Invertebrate Fossils of the Navarro Group bedding has been observed in some of the sand beds and in places the broken con­dition of the fossil shells indicates that locally the sediments were laid down in the zone of active wave action. Bentonite forms a minor, though well distributed, purt of the group. The aggregate thick­ness of these sediments is estimated to range from 550 to 750 feet or more. The group appears in surface outcrops in Texas in a belt 1 to 23 miles wide (figure 1) extending from Red River val­ley in Bowie County in the northeast, westward to Hunt County, thence south­ward and southwestward to Rio Grande valley in Maverick County. The belt is in general gently rolling, becoming mod­erately hilly only where underlain by the relatively more resistant sandy facies of the group, and in the breaks of the larger streams crossing the belt. Most of the area is under cultivation. The belt is ex­ceptionally wide in Hunt County and in Maverick County, due to the flattening out of the strata composing the group in those areas; elsewhere the belt is much narrower, decreasing in places to a mile or less, as in Bexar County and in southern Uvalde County, where the section is partly, and in places completely, cut out by faulting. Jn east-central Texas the belt forms the eastern part of the physiographic division known as the Black Prairies. The marls, clays, and sands composing the group weather to gray and black soils and subsoils that blanket and effectually conceal the true nature of the formations, except in fresh exposures afforded by the banks and bluffs of streams, gullies and buld spots in the fields, and artificial ex­cavations such as road and railroad cuts and ditches. Because of this covering of weathered materials the differentiation and mapping of the formations of the group has been a slow, laborious process, requir­ing long continued search for such ex­posures of the strata as are available for study. The five formations of the group in­dicated on a previous page have been satis­factorily differentiated and mapped, not in detail, hut in a somewhat generalized fashion (geologic map, 1937), from Hunt County to the Rio Grande in Mav­erick County; from Hunt County eastward e ~ ,.. East-central j Texas ,. w l c: Q) Wills Point ~Cl ~a c Ul ~Q) f'ormation j '­o·­ ~5 C) r.. :'Q"' z- a;m ~'OI Kincaid J: c CL ()(tf formation "I:·­ Kemp clay a' 0.. c :J 0 -;; ~ t. J: -? 'o.O Q Corsicana marl b '[ 0 {_ 'ti t. Nacatoch sand c m ~ > cu 2 z Neylandville m arl d ,...'?­ Ill (Upper psrt) .! t. QJ Ill t. .... -p;c;;,<;ag:­ c. lO ,,.._ , ro In 0 ~ J 0 (Lower part) ~ (,) ttl ~ (() - ~ L (.) t. I Austin chalk Q) 0 0. .~c 0. 5.~ :::> ~ c RI t: Eagle Ford share ~ :l t­ ~ - c It c ~: ~ Woodbine sand 0 E c Q) u a-105 species and variet ies b-98 species and varieties ·-245 species and variet ies d-100 species and varieties The University of Texas Publication No. 4101 tu Bowie County the different formations of the group have been recognized in scat­tered outcrops, but their distribution has been inadequate I y determined, and the undifferentiated group as a whole is repre­sented on the map. Throughout the area of the group in Texas the mapping of the finer details of the boundaries and the recognition and tracing of individual beds and fossil zones within the formations, still remains to be done. The fossils are not uniformly distributed throughout the 95• group, some parts of each of the forma­tions being barren, or nearly so, of the remains of macroscopic organisms; in some layers, lenses, and concretionary masses these larger fossils are present in greater or less abundance. Because of the inadequacy of the field work it has not been possible to indicate the exact zonal position of many of the individual fossil collections, but so far as possible the distance of each lot above the base or below the top of the containing formation Fig. 3. Map howing fos il localitie of th Navarro group in Bowi and Red River countie . oll tion number of the Unit d tat Geological ur , y ar pla d adja nt to the locality ymbol (X). Fig. 4. Map wing fo il l calitie of th in Franklin, Hopkin , and Delta counti . oll ction numb rs of th nit · <:::! ~ ~­ Ct> ~ ~ ~. ~ ~ c '-+. ~ Ct> ~ ~ ~ ~ ~ O" ~ ~. (") ~ <:"+. c ~. ~ . ~ c {;-.. ....... c ....... Invertebrate Fossils of the Navarro Group Navarro group, as follows: Dalcoticancer overana australis Rathbun, from the Corsi­cana marl 6 miles east of Castroville, in Bexar County (U.S.G.S.coll. 16156) ; N otosceles bournei Rathbun, from the Kemp clay near Elgin, Bastrop County; Ophtkalmoplax stephensoni Rathbun, from the Escondido formation, southern Mav­erick County (Univ. Texas K512); Pal­aega williamsonensis Rathbun, from the Kemp clay 21h miles southwest of Thrall, Williamson County (type locality) . Aside from shark teeth, which are fairly common, vertebrate remains are rare and widely scattered in the Navarro group. They include teeth, scales, and otoliths of fish, and vertebrae and fragments of other hones of swimming reptiles, such as mos­asaurs and plesiosaurs; these have not been systematically studied. The figures given on following pages for the range and distribution of genera and species should he regarded as tenta­tive and subject to revision from time to time as additional collections throw new light on these subjects. It is believed, however, that the collections already made are sufficient to show the general order of the range relationships, and that those species that may he found to have a greater range than previously supposed, will be off set in part at least by the finding of new species of restricted range. Furthermore, certain changes could be made in the nu­merical range relationships by slightly different classificatory treatment of the organisms. For example, by treating the subgenera Cam ptonectes, Syncyclonema, Neithea, and Radiopecten in the family Pectinidae and Granocardium, Pachycar­ dium, and Ethmocardium in the family Cardiidae, as genera, seven are added to the list of Navarro genera that do not range upward into the Tertiary. NEYLANDVILLE MARL DEFINITION The Neylandville marl consists of 150 to 300 feet of gray sandy, calcareous clay or marl that rests unconformably upon the Taylor marl, and is conformably (?) over­lain by the N acatoch sand. The formation has been traced in a narrow belt of out­crop from the type locality near Neyland­ville in Hunt County, southward through Kaufman, Navarro, Limestone and Falls counties, to the vicinity of Buckholtz in Milam County, south of which it is over­lapped and concealed by the transgressing Corsicana marl. The base of the forma­tion is marked by a sandy, glauconitic bed containing scattered phosphatic nodules and phosphatic internal molds of fossils, mainly mollusks. Bentonite forms a sub­ordinate part of the group. As seen at a few favorable localities the unconformity at the base of the formation is sharp, gently undulating, and more or less irregular in detail. It probably does not represent a relatively long period of geologic time. The contact of the forma­tion with the overlying Nacatoch sand has not been seen clearly exposed but at one small poor exposure in a road ditch 3% miles north by west of Cash, a mile west of Highway 34, Hunt County, a 6-inch bed of soft sandstone, resting upon sandy marl containing Exogyra cancellata Stephenson, is believed to mark the contact. No def­inite evidence of an unconformity was ob­served. The formation is more or less fossil­iferous in its different parts and is partic­ularly characterized by the shells of Exogyra cancellat,a Stephenson and Anomia tellinoides Morton. The formation marks the lower limit of the range of Exogyra costata and the upper limit of the range of the ammonite genus Placenticeras, large specimens of which, belonging to the species P. meeki Bohm, are present in a zone well above the base. In Navarro County the formation contains soft, richly fossiliferous concretions of calcium car­bonate, which have yielded a varied fauna, mainly of pelecypods, gastropods, and ammonites, many species of which are not known outside of this formation, and some of which will doubtless prove to be re­stricted in range to this unit. ANALYSIS OF THE FAUNA The Neylandville fauna (table 1, in pocket) includes 102 named species and varieties of invertebrates, including species of Vermes, 1 of Echinodermata, and 100 species and varieties of Mollusca. Of the Mollusca, 43 are Pelecypoda, 3 are Scaphopoda, 38 are Gastropoda, and 16 are Cephalopoda. In addition to the named forms there are 30 or more forms The University of Texas Publication No. 4101 listed as unidentified species; these are dis­regarded in the further consideration of the fauna. The one species of Vermes, Ser pula cre­tacea (Conrad), is long ranging in Uppet Cretaceous marine strata younger than the Austin chalk. The one species of Echinodermata, H emiaster benhurensis, is recorded only from one locality in the Neylandville marl, and from one locality in the lower part of the overlying Nacatoch sand. Of the 100 species and varieties of Mol­lusca, 56 are described as new species and 8 as new varieties, making a total of 64 new forms. In the further analysis of the fauna the varieties will be counted as species. Of the 64 new forms, 37 as now known are restricted to the Neylandville; 27, one questionably, range upward into the Naca­toch sand, and of the 27, 3 range upward into the Corsicana marl; 3, one question­ably, into the Kemp clay; and 2 range downward into Taylor marl equivalents. Two of the new species that range upward into the N acatoch are present also in the N acatoch sand of Arkansas; these are Parapachydiscus arkansanus and Scaphites rugosus; one species, Baculites clavif ormis, occurs in the Coon Creek tongue of the Ripley formation in Tennessee. The range of these new forms indicates a close fauna} relationship with the Nacatoch sand. The number of the new forms that will even tu ally prove of value as index fossils is problematical, but doubtless some of them will be found to be definitely re­stricted to the Neylandville and to beds of Neylandville age. Some are unique forms not closely related to previously known Upper Cretaceous genera and species in the Coastal Plain. Such are the gastropod Tundora tuberculourille, H., Molluequea fouilea [Penla] : Miuion 1elenti&qae en Perae (par. J. de Morpn), Tome 3, ttude1 1Hlosfque1, Pt. 4, Paleontolotie, p. 255, pl. 35, fip. la, lb, 190&. common species, and in general the faunas are not very closely related; a few species appear to he good analogues of Navarro species. The series includes the follow­ing groups: Ootatoor ( Cenomanian) , Trichinopoly (Turonian), Ariyalur, in­cluding Valudayur beds (Maestricht­ian) . 64 The V a I u d a y u r beds near Pondicherry yielded Ammonites siva Forbes,65 a species which Hyatt later trans­ferred to the genus Sphenodiscus. Other species described by For bes in the same paper (from the Ariyalur group, includ· ing Valudayur beds), which appear to he fairly close analogues of Navarro species, are: Strombus uncatus (p. 129, pl. 13, fig. 16) , analogous to Pugnellus densatus Con· rad, and Cardium lucerna (p. 145, pl. 17, fig. 10) , analogous to Lio pistha protexta (Conrad) . Kossmat has identified Para­pachydiscus gollevillensis (D'Orbigny) from the Trigonarca beds of the Ariyalur group. The paleontologic evidence ap­pears to justify the reference to the Ariyalur group (including the Valudayur beds) to the Maestrichaan. Upper Cretaceous sedimentary beds in the Mari Hills of Baluchistan, which Noetling66 correlated with the Maestricht· ian, have yielded several species hearing some resemblance to Navarro species. H emiaster oldhami N oetling is similar to H. bexari Clark, but the ambulacral areas are larger and the tubercles are coarser. Gryphaea vesicularis Lamarck resembles some of the variations of G. mutabilis Morton. Pugnellus crassicostatus N oetling is somewhat like P. densatus Conrad, but is not a close analogue. S phenodiscus "Blanford, H. F., On the Cretaceous and other . rock.a of the South Arcat and Trichinopoly Di1trict1, Madr&1: Mem. Geol. Survey India, vol. 4, pt. 1, pp. 26, 151-164, 1862. Stoliczka, Ferdinand, Cr.ataceous faunas of 1outhem India: India Geol. Survey Mem., Palaeontologia Indica, 1865-1870. Ko..mat, Franz, The Cretaceou1 deposits of Pondicherri: Rec. Geol. Survey India, vol. 30, pt. 2, pp. 52-110, 1897. Vredenburg. E., The Cretaceous Orbitoide1 of India: Rec. Geol. Survey India, vol. 36, pt, 3, pp. 171-213, 1908. Holland, T. H., and Tipper, G. H., Indian geoloeical terminology: Mem. Geo}. Survey India, vol. 43, pt. 1, p. 121, 1913. 85Forbea. Edward, Report on the £o11il invertebrata from southern India, collected by Mr. Kaye and Mr. Cunliffe: Trana. Geol. Soc. London, vol. 7, pp. 97-174 (esp. p. 110, pl. 7. 61. 6). 1846. 08Noetling, Fr;u, Fauna of the Upper Cretaceou• (Maeetricbtian) bed1 of the Mari Hilla: Geol. Survey India. Palaeontologia Indica, Serie1 16, Fauna of Baluchistan, vol. 1, pt. 3, 79 pp., 23 pl1.. 1897. The University of Texas Publication No. 4101 acutodorsnnation. L. W. Stephen­son, 1928. 14136. Field near the Wortham road, 5 miles east of Cooledge, Limestone County; yellowish fossiliferous limestone concretions, upper part of formation. L. W. Stephenson, 1928. 14138. Weathered out of upper part of formation in field near oil-prospecting well of Moss & Keeling, W. D. Moody No. 1, 1h mile south-southwest of McLeod School, about 6% miles southwest of Currie, Navarro County. L. W. Stephenson, 1928. 14139. Branch 1h mile south of McLeod School, 61h miles southwest of Currie, Navarro County; 15 feet of dark shaly clay with fossils in lower 4 to 6 feet, upper part of formation. L. W. Stephenson, 1928. 14158. Deep ditch north of railroad, 3% miles east of Manor, Travis County; earthy, very impure soft limestone. L. W. Stephenson, 1928. 14162. Willow Creek, below the Austin highway, 5 miles west by north of Elgin, Travis County; 10 feet of dark calcareous clay, about middle of formation. L. W. Stephenson, 1928. 15434. Half a mile west of Odds, Lime­ stone County. Julia Gardner, 1930. 15518. Eastward-facing slope of Leon Creek valley, about 1h mile above the Southern Pacific ( G.H.&S.A.) R.R. bridge, Bexar County; green­ish-gray calcareous clay, upper part of formation. L. W. Stephenson, 1930. 15519. Ravine on eastward-facing slope of Leon Creek valley, a mile above the Southern Pacific (G.H.&S.A.) R.R. bridge, Bexar County; greenish-gray calcareous clay, upper part of for­mation. L. W. Stephenson, 1930. 15525. Same as 7638. L. W. Stephenson, 1930. 15528. Deep roadside gully, 3/5 mile west of Elm Creek school, 4% miles northwest of Lockhart, Caldwell County; calcareous, ferru­ginous fossiliferous concretions in dark clay, upper part of formation. L. W. Stephenson, 1930. 15529. Gully west of Austin-Lockhart road, 1 3/10 miles south of Mendoza, 4% miles west of Lytton Springs, in Caldwell County; 6 feet of gray calcareous clay forming the uppermost bed of the formation, unconformably overlain by the Kincaid formation (Paleocene). L. W. Stephen­son, 1930. 15533. Yellowish concretions in a field 2 miles south of new Garfield store, l % miles northwest of Texas Hill, Travis County; upper part of formation. L. W. Stephenson, 1930. 15534. Same as 14158. L. W. Stephenson, 1930. 15537. Branch of Mustang Creek above and below the Taylor-Noack road, 3 miles south, 30° west of Thrall, Williamson County; 6 to 10 inches of cream-colored soft earthy limestone with many dark phosphatic pobbles, phosphatic molds of gastropods and pelecypods, and a few non-phos­phatic gastropods and corals; forms basal bed of the formation, and rests unconformably on the Taylor marl. L. W. Stephenson, 1930. 16141. From a wash in a field 3 miles south­east of Manor, Travis County; yellow calcareous concretions in upper part of formation; the horizon is less than 20 feet above a bed carrying an abundance of ldonearca deatsvillensis Stephen­son. L. W. Stephenson and F. L. Whitney, 1932. 16142. Earth tank in a draw, 314 miles southeast of Manor, Travis County; earthy lime­ The University of Texas Publication No. 4101 stone in upper part of formation. L. W. Stephen­son and F. L. Whitney, 1932. 16146. Near head of small branch, 2/5 mile west of public road, 214 miles north by west of Deatsville, Travis County; dark clay in middle or upper part of formation. L. W. Stephenson and C. E. Cook, 1932. 16149. Washes in field east of Luling-San Marcos highway, 3% miles north-northwest of Fentress, Caldwell County; gray shaly clay ·wit~ calcareous, ferruginous fossiliferous concretions, upper part of formation. L. W. Stephenson, 1932. 16151. Same as 15528. L. W. Stephenson and E. V. Woolsey, 1932. 16489. Small arroyo east of Cibolo Creek, % mile north of the crossing of the Zuehl road, Guadalupe County. A. N. Sayre, 1933. 16668. Earth tank west of public road, about 2 miles south-southeast of Schumansville, 9/10 mile south-southeast of the crossini: of Long Creek, Guadalupe County; calcareous concretions in dark clay, near base of formation. L. W. Stephenson, 1934. 17367. State Highway 22, east of Beaton tank, 3 miles southeast of the courthouse at Cor­sicana, Navarro County; gray shaly clay, upper part of formation. L. W. Stephenson, 1936. 17370. Same as 15537. L. W. Stephenson, 1936. 17372. Westward-facing slope of Big Creek valley, 3 miles southwest of Stranger, 1 3/10 miles southeast of Parsons Bridge, Falls County; yellowish septarian concretions in field 40 feet above Big Creek bottom, upper part of formation. L. W. Stephenson, 1936. 17373. Light-yellowish concretions in field north of road, 1 mile west by south of Odds (Limestone County), in Falls County; 15 to 20 feet above Big Creek bottom; upper part of formation. L. W. Stephenson, 1936. 17374. Field east of the old Wortham road, 2% miles northeast of the junction with U.S. Highway 84, about 41h miles east of Cooledge, Limestone County; orange-colored septarian con­cretions in dark shaly clay, upper part of fo:ma­tion. L. W. Stephenson, 1936. 17375. Public road 314 miles north-north­west of Bazette, 1 % miles north-northwest of Buffalo School, Navarro County; poor exposure of dark clay with an interhedded 6-inch shell layer composed mainly of Crassatella in fragmentary condition hut including a goodly number of com­plete valves; this bed lies within 15 or 20 feet of the top of the formation, and about 52 feet lower than the crest of the hill to the south; this locality was discovered by F. B. Plummer, who called attention to it. L. W. Stephenson, 1936. 17376. Field east of public road, 3 4/5 miles north-northwest of Bazette, l % miles north-north­west of Buffalo School, Navarro County; shells of the Crassatella bed described under 17375, weathered out in northwestward-£ acing slope. L. W. Stephenson, 1936. 17377. Same as 14139. L. W. Stephenson,1936. 18196. On a hillside by a road 2 2/5 miles southeast of Manor, Travis County. This collec­ tion was received too late to be included in the table of distribution and range (Table 4). John W. Wells, about 1936. Texas Bureau coll. 739. Dam on Cedar Creek 10 miles south-southeast of Greenville, Hunt County. E. H. Sellards, 1922. Texas Bureau coll. 903. 1 mile east of Kimbro, Travis County. Texaa Bureau coll. 1170. 4 miles north· west of Lockhart, Caldwell County. Texas Bureau coll. 1173. 3 miles north· west of Lockhart, Caldwell County. Texas Bureau coll. 1174. 3 miles north· west of Lockhart, 1h mile southwest of well on Plum Creek, Caldwell County. Texas Bureau coll. 2398. Edd Myer's place 2 miles [?] east of Manor, Travis County. Texas Bureau coll. 2399. Near Gilleland Creek, Buckman Survey 4 miles south of Manor, Travis County. Hill coll. 8, in U.S. Nat. Museum. "Glauconitic division" in the vicinity of Webber· ville, Travis County. See 7601. R. T. Hill and T. W. Vaughan, 1894. SYSTEMATIC PALEONTOLOGY Phylum PORIFERA Class SPONGIAE Subclass SILICISPONGIAE Order MONACTINELLIDA Family CLIONIDAE Genus CLION A Grant The genus Cliona is based on a boring sponge inhabiting the waters of the Firth of Forth, Scotland. The name was intro• duced by Grant77 in 1826, who in the same article named and described the type species, Cliona celata. The casts of sponge borings, commonly referred to Cliona, occur abundantly in certain beds, usually calcareous, in the upper part of the Upper Cretaceous (Exogyra costata zone) of the Atlantic and Gulf Coastal Plain. The borings are in thick-shelled mollusks, the forms of which may be faithfully preserved by the net· work of casts even after the shell sub­stance has been completely dissolved away (pl. 3, figs. 1, 4, 5). The casts are as a rule phosphatic. A few casts of Cliona have been found in the Navarro group of Texas. CLIONA MICROTUBERUM Stephenson, n.ap. Pl. 3, figs. 1-5; pl. 5, figs. I, 2 A bor~ng spon~e preserved as sandy phosphat1c casts m the thick shells of 77Grant, R. E., Notice of a new zoophyte (Cliona celata, Grant) from the Firth of Forth: Edinburgh New Philo1ophi· cal Jour., vol. I, pp. 78-81, 1826. Invertebrate Fossils of the Navarro Group mollusks. The specimens are often found with the inclosing shell dissolved away, leaving the casts freely exposed. The openings through which the sponge enters the shell range in diameter up to 2 mm. or more, and the excavations made within the shell are in the form of more or less irregular interconnecting channels rang­ ing up to 5 mm. or more in cross section. In some specimens the channels are turnip­ shaped, flattish jug-shaped, or irregularly ovate, and they may be aligned in rows interconnecting one with another by means of smaller channels (pl. 3, fig. 3) , or they may be irregularly distributed within the shell. The casts are generally hard and firm but may be in any degree of induration from soft to hard. The ma­ terial filling the borings is generally phos­ phatic and more or less sandy. The sur­ face of the cast is densely stippled with tiny tubercles (pl. 3, fig. 2). No spicules have been detected in the material form­ ing the casts. Intermingled in intimate association with the Cliona casts are problematical casts of slender, smooth, or very finely granular, intercommunicating cavities, which probably pertain to an undeter­mined organism, perhaps a sponge (pl. 5, fig. 1); they are mostly less than a milli­meter in diameter and tend to be straight or gently curved for stretches as great as 7 or 8 mm., but in places they are very irregular in trend; they have a twisted appearance and may be irregularly fur .. rowed in a general longitudinal direction. In one small shell fragment from the Kemp clay (7601) the borings and their ·associated casts are mainly of this slender sort (pl. 3, fig. 6, U.S.N.M. no. 76269). Casts of borings regarded as belonging to Cliona, from the Navesink marl of New Jersey, were described as new in 1932 by Fenton and Fenton,78 under the name C. cretacica. The authors were doubtless unaware that a nearly identical name, Cliona cretacea (Portlock) had previously been applied to a species of boring sponge from the Upper Cretaceous 18Fenton, Carroll Lane, and Fenton, Mildred Adami, A new 1peciH of Cliona from the Cretaceous of New Jersey: Amer. Midland Naturalist, vol. ll, no. 2, p. 55, pl. 7, ,,•• 8, 9. chalk of England. 79 The later name is valid, however, if the recommendation of the International Commission on Zoologi· cal Nomenclature is accepted, namely, that names once introduced are not to be rejected because of a slight variation in spelling. The holotype of Cliona cretacica (New Jersey State Museum No. 8184) should he preserved in the State Museum at Trenton, New Jersey, but it can not be found there and is apparently lost. The figured para­type (New Jersey State Museum No. 8185, fig. 8) is preserved, but it shows only the openings into the shell and does not show the form of the cast. Since the published figure of the holotype of the New Jersey species does not show stippling on the surface of the casts, and no mention is made of this feature in the author's de­scription, the Texas material can not he safe I y referred to it. In the New Jersey State Museum col­lection is an unnumbered shell of Gryphaea from the type locality of Cliona cretacica, which has been thoroughly per­forated by boring sponges and the strong I y phosphatic casts are well exposed by subsequent deep corrosion. These casts, labelled Cliona sp. by the Fentons, appear to represent two organisms, one of which has the irregular form and sur­face stippling of Cliona microtuberum, and may be that species, although the average diameter of the casts is somewhat less. The other organism is represented by long smooth, more or less curved casts having about the same average diameter as the Cliona; these casts are much larger and lack the twisted form of the slender species associated with the type of C. microtuberum. The Fentons examined this specimen, compared it with the holo­type of C. cretacica, and did not consider either of the two kinds of casts as repre­senting their new species. Types.-Holotype, U.S.N.M. no. 76266; two figured paratypes, U.S.N.M. no. 79Fiacher, M. P., Recherches aur lea eponge1 perforantes fossiles: Mus. histoire nat. Paris, Nouvelles, Archie1, tome 4., p. 167, pl. 25, figs. Sa·d, 1868. (See synonymy.) Portlock originally called the species Entobia cretacea. (See J. E. Portlock, Report on thu geology of the County ol Londonderry, p. 360, 1843.) The University of Texas Publication No. 4101 76267; 1 figured paratype, U.S.N.M. no. 76268; 1 figured paratype, U .S.N .M. no. 76270. Distribution in T exas.-Navarro group, Corsicana marl: 1~i miles south by east of Oak Grove (13568, figured; 16160); 7 miles south, 3 miles east of Greenville ( 11250, holotype) ; well on G. A. Harper Survey (at a depth of 1045 feet) , Medina County (13844). Navarro group, Kemp clay: 12 miles southeast of Greenville ( 1124 7). Outside distribution. -Mississippi: Prairie Bluff chalk. Alabama: Prairie Bluff chalk. New Jersey: N avesink marl ( repre­ sented in New Jersey State Museum by a specimen labeled C liona sp.) Range.-The phosphatic remains of boring sponges closely similar to Cliona microtuberum are common in the upper part of the Upper Cretaceous series of the Atlantic and Gulf Coastal Plain; they are particularly abundant in the Prairie Bluff chalk of Mississippi and Alabama. These organisms have never been systematically studied. Phylum VERMES Class CHAETOPODA Order TUBICOLA Family SERPULIDAE C.nua SERPULA Linne SERPULA CRETACEA (Conrad) Pl. 4, figs. 1-3 1875. Dipfoconcha cretacea Conrad, Geol. Survey North Carolina Re pt., vol. 1 (by W. C. Kerr), App. A, p. 12, pl. 2, fig. 26. 1892. Diploconcha (Serpula?) cretacea (Con­rad)?. Whitfield, U.S.Geol. Survey Mon., vol. 18, p. 170, pl. 20, fig. 25. (Geol. Survey New Jersey, Paleontology, vol. 2, p. 170, pl. 20, fig. 25.) 1892. Dentalium ( F alcula) falcatum (Conrad) . Whitfield, U.S.Geol. Survey Mon., vol. 18, p. 169, pl. 20, figs. 15-17 (not figs. 12-14, 18). (Geol.Survey New Jersey, Paleontology, vol. 2, p. 169, pl. 20, figs. 15-17.) 1907. Serpula whitfieldi Weller, Geol. Survey New Jersey, Paleontology, vol. 4, p. 308, pl. 19, fig. 2. 1916. Serpula whitfieldi Weller. Gardner, Mary­land Geol. Survey, Upper Cretaceous (2 vols.), p. 746. 1923. Serpula cretacea (Conrad). Stephenson, North Carolina Geol. and Econ. Survey, vol. 5, p. 67, pl. 9, figs. 1-7, 10, n (questionably figs. 8, 9, 12) . 1928. Serpula cretacea (Conrad). Adkins, Univ. Texas Bull. 2838, p. 78. ?1929. Serpula cretacea (Conrad) . Trechmann, Geol. Mag., vol. 66, no. 785, p. 486. Calcareous sinuous, gradually tapering tubes, occurring singly, in pairs or in col­onies. Tube wall thin and fragile in the early stages, becoming gradually thicker to moderate thickness in later stages; structurally the walls are composed of a series of thin layers in the form of grad­ually enlarging truncated cones, one fitting snugly within the other, and ending orally in a thin edge; these layers are secreted by the animal as it grows larger and moves gradually outward in the tube. Fine transverse growth lines cover the outer surface on the younger stages; these tend to grow coarser away from the small end and may become quite coarse or undulat· ing on large tubes. The species is char· acterized by its extreme sinuosity which may be any sort of irregularity, may simulate a coiled gastropod, or may form a closely adhering or intertwining colony of numerous tubes. The tubes are cir· cular in cross section and range in diameter from a millimeter or less at the small end to 9 millimeters at the large end of the largest tube in the Texas material; in the latter the tube wall attains a maxi­mum measured thickness of about 1.5 mm. One tube about 2.2 mm. in diameter con· tains a fragment of a calcareous oper­culum which is slightly concave on its outer surface and is ornamented with 10 or 12 (estimated) radiating primary ribs and perhaps as many intercalated secondaries; the point of radiation appears to he acentric. The broken edge of the prong which extends inward from the inner side of the operculum is visible, but is too imperfectly exposed for description. The ornamentation on this operculum is similar to that on the operculum described by W ade80 under the name Hamulus sp., but the specimen is smaller and the or· namentation is not quite so pronounced. The operculum described by Gardner81 80Wade, Bruce, U. S. Geol. Survey Prof. Paper 137, p. 31, pl. 2, figs. 9-11, 1926. 81Gardner, Julia, Maryland Geol. Survey, Upper Cre· taceoua (2 vols.), p. 748, pl. 47, figs. 16-19, 1916. Invertebrate Fossils of the Navarro Group under the name Ornalaporta marylandica is very much more finely ornamented. Both Wade's and Gardner's specimens probably pertain to Serpula; in both the Texas specimen and the Maryland speci­mens, the opercula are obviously situated far down in the tubes below the outer apertures. In the simple tubes here ref erred to Serpula cretacea (Conrad) there are no characters to enable one to differentiate species. Were opercula preserved in all the tubes they might aflord a basis for specific separation, for the three opercula here mentioned (from Texas, Tennessee, and Maryland) are differently ornamented and may represent as many species. Types.-The specimen from Snow Hill, North Carolina, originally figured by Con­rad, is probably lost. A specimen from the same locality labelled in Conrad's handwriting may he considered a cotype (U.S.N.M. no. 31905) 82 ; it consists of a pair of attached strongly curved tubes about 35 mm. long. Two plesiotypes from Texas, U.S.N.M. no. 21001; 1 plesiotype from Texas, U.S.N.M. no. ~- Dutribution in Texas.-Navarro group, Neylandville marl: 21h miles north of Curbet (16170, 17365) . Navarro group, Nacatoch sand: Vicin­ity of Kaufman (761, and U.S.N.M. no. 21001) ; field 2 miles southwest of Kauf­man (7547); road 2 miles southwest of Kaufman ( 7546) ; field south of Chatfield ( 7569) ; Watkins' place 3 miles north of Corsicana (9552) . Navarro group, Corsicana marl: About 5 miles east by north of Greenville ( 12924) ; well 7/20 mile south by west of SL Mary's University, Bexar County (16353). Navarro group, Kemp clay: near old Garfield (7603) ; west of Zuehl (7721) . Outside distribution.-Mississippi: Rip· ley and Owl Creek formations. North Carolina: Snow Hill member of Black Creek formation and upper part of Peedee formation. Maryland: Monmouth formation. .,lawNd in North Carolina Geol. and Econ. Survey, •ol. S, pl. 9, 6-. S, 1923. New Jersey: N avesink mar I. Jamaica, B.W.I.: Questionably in shales of Blue Mountain summit. Range.-Calcareous tubes of Serpula, which can not he distinguished from S. cretacea (Conrad) , are common in the upper part of the Exogyra ponderosa zone and in the Exogyra costata zone, in the Atlantic and Gulf Coastal Plain. SERPULA? LINEATA (Weller) Pl. 4, figs. 4-6 1907. Hamulus lineatus Weller, New Jersey Geol. Survey, Paleontology, vol. 4, p. 310, pl. 19, fig. 7. 1923. Serpula lineata (Weller). Stephenson, North Car~ina Geol. and Econ. Survey, vol. 5, p. 70, pl. 9, figs. 13, 14. Calcareous tubes of small diameter, nearly straight or slightly sinuous, very gradually tapering. In the Texas material the smallest diameter measured is about. 1.5 mm. and the largest diameter 4.5 mm.; shell wall at small end about 0.25 mm. thick and at large end 1 mm. thick. The figured specimen (pl. 4, fig. 5) is a fragment 29 mm. long, 4 mm. in diameter at the small end and 4.5 mm. in diameter at the large end. The tubes of this species are more gently tapering, thicker-walled, and in general more nearly straight than are the tubes of Ser pula cretacea (Conrad) ; the truncated cone-shaped layers which make up the tube wall are more gradually tap· ering. Types.-Holotype; an internal mold from the Merchantville clay at Lenola, New Jersey; preserved in the State Museum at Trenton, New Jersey. Four plesiotypes from Texas, U.S.N.M. no. 20891. Distribution in Texas.-Navarro group, Nacatoch sand: North edge of Corsicana (518). Navarro group, Kemp clay: Webber­ville (7601). 0 u ts id e distribution. -Mississippi: Coon Creek tongue of Ripley formation, and Owl Creek formation. Chattahoochee region (Al ab am a. Georgia): Blufftown formation and Rip­ley formation. North Carolina: Snow Hill member of Black Creek formation. The University of Texas Publication No. 4101 New Jersey: Merchantville clay and Navesink marl. Range.-Ranges through the zones of Exogyra ponderosa and E. costata in the Atlantic and Gulf Coastal Plain. SERPULA BOWIENSIS Stephenson, n.ap. Pl. 4, fig. 7 Tube irregularly sinuous, tapering rap· idly, attached on one side to a fragment of an oyster shell; tube wall thin except along the area of attachment where it thickens and flares irregularly outward, producing a broad base. Upper surface ornamented with three sharp, rather prominent, gently and finely fluted longi­tudinal ridges. The tube is imperfect at both ends, but as preserved is about 28 mm. long, and increases in diameter from about 3 mm. at the small end to nearly 10 mm. at the large end. The transverse growth lines are very fine. The inner surf ace is partly exposed at the large end and, though somewhat corroded, is notice­ably undulating. This species is similar to Ser pula bar­bata Morton,88 but the longitudinal ribs on the latter are more widely separated and the tube tapers less rapidly; because of these differences and the lack of in­formation as to the locality and geologic position of the Alabama material, it seems best to apply a new name to the Texas specimen. Ser pula bowiensis appears to be closely allied to Serpula fluctata Sowerby,84 a small slender species with 3 fluted ribs on the attached part of the tube, and 5 on the free part, from the Upper Chalk (Maestrichtian) at Norwich, England. Holotype.-V.S.N.M. no. 76271. Distribution in Texas.-Navarro group, Corsicana mar 1 : 11;4 miles south by east of Oak Grove (16160); ?7/20 mile south by west of St. Mary's University, Bexar County (16353). 88Morton, S. C., Synopsis of the oraanic rema!n1 of the Cretaceou1 Croup of the United State1, p. 73, pl. 15, 61. 12, 1834. 14Sowerby, James, Min, Concho),, vol. 6, p. 228, 611. 5, 6, 1829. Genus HAMULUS Morton HAMULUS ONYX Morton Pl. 4, figs. 8, 9 1834. Hamulus onyx Morton, Synopsis of the organic remains of the Cretaceous group of the United States, p. 73, pl. 2, fig. 8; pl. 16, fig. 5. 1905. Hamulus onyx Morton. Johnson, Acad. Nat. Sci. Philadelphia Proc., vol. 57, p. 4. 1916. HamulUs onyx Morton. Gardner, Maryland Geol. Survey, Upper Cretaceous (2 vols.), p. 747. 1921. Hamulus onyx Morton. Wade, U.S.Nat. Mus. Proc., vol. 59, p. 43, pl. 9, figs. 1-3, 5, 6. 1923. Hamulus onyx Morton. Stephenson, North Carolina Geol.• and Econ. Survey, vol. 5, p. 76, pl. 10, fig. 11. 1926. Hamulus onyx Morton. Stephenson, Geol. Survey Alabama, Special Rept. No. 14, p. 250, pl. 92, fig. 2. 1926. Hamulus onyx Morton. Wade, U.S.Geol. Survey Prof. Paper 137, p. 30, pl. 2, figs. 4-7, 12. 1929. Hamulus onyx Morton. Dane, Arkansas Geol. Survey Bull. 1, p. 150, pl. 27, fig. 2. Tube small, regularly tapering, curved more or less in the early stages, with a tendency to straighten out in the adult stages; the degree of curvature is variable in different individuals and the curvature may or may not be exactly in one plane. Six strong, subequal longitudinal ribs ex· tend the entire length of the tube; the ribs are smoothest at the small end, but become irregularly rugged and subangular to rounded on the crest toward the large end; the inters paces are broadly V-shaped on the bottoms. One fragment of a tube contains an operculum, the inner tooth-like projection of which is embedded in the matrix filling the tube; the outer surface of the opercu· lum is slightly corroded, but is similar to the one described by Wade, being slightly · concave, acentric, and nearly smooth. The approximate dimensions of the best preserved Texas specimen (pl. 4, fig. 8) are: Length measured centrally around the curve of the tube 16 mm. ; diameter at small end which is not quite complete, 1.1 mm.; diameter at large end measured on the outer crests of the ribs, 3.8 mm.; diameter of aperture 2 mm. The shell structure of Hamulus tubes was described by the present writer in volume 5 of the North Carolina Geological and Economic Survey (p. 71, pl. 10, figs. Invertebrate Fossils of the Navarro Group 5, 9a). The tubes are generally found free in their containing matrix. Among hundreds of specimens examined only two have been found definite} y cemented to objects. One of these, a tube about 8 mm. long, is attached throughout its length to the shell of Anomia argentaria Morton; the other, a curved tube about 11 mm. long, from the Ozan formation of Arkansas, is attached along about 8 mm. of its length to the curved surface of a small novaculite pebble. Most of the ribbed worm tubes having the general form of H amulus, from the European Cretaceous, have a number of ribs other than six (4, 5, 7), but two species having that number are recorded by Gold­fuss.85 Serpula sexangularis Miinster is from "blauen Kreidmergel zu Rinkode bei Munster," and Serpula sexsulcata is from "einer kalkhaltigen Schist iiber dem Eisensande bei Amberg." Both of these species appear to be rather closely related to H. onyx Morton. Type.t.-Collection of the Academy of Natural Sciences of Philadelphia. Morton cited the species from L'.ynchs Creek, South Carolina, and from the "older Cre­ taceous deposits" at Erie, Alabama, and figured one specimen from each locality. In the collections at the Academy are four specimens from the Tombigbee sand member of the Eutaw formation at Erie IDuft, Warrior River, Hale County, Ala­ bama. The word "type" is not present on Morton's original label, but appears on two later labels. The Lynchs Creek ma­ terial is probably lost and old Erie, Hale County, Alabama, may therefore appro­ priately be regarded as the type locality. Plesiotypes from Texas, U.S.N.M. nos. 76272, 76273. Di&tribution in Texas.-Austin chalk: Excavation for a sidewalk on Webster Avenue, between 19th and 20th Streets, Waco, McLennan County ( 7560). Bonham clay (Austin age): Randolph road, 6 miles (by the road) southwest of Bonham, Fannin County (10557). Taylor marl: Old highway, westward­facing slope of Little Walnut Creek valley, "Goldfuu, Aup1t, Petrefacta Cennaaiae, p. 238, pl. 70, &p. 12, 13, 1826. about 2 miles southwest of Sprinkle, Travis County (14160); Guadalupe River, 4 miles below New Braunfels, Guadalupe County (U.S.N.M. no. 21205); private road, eastward-facing slope of Salado Creek valley, about 2 miles above the crossing of the Missouri, Kansas & Texas R.R., Bexar County (7648). Pecan Gap chalk (Taylor age): About 200 yards south of the Branson Brick Company's plant, at southwest edge of Marlin, Falls County (12915); Cedar Springs road, 5 3/10 miles south by east of Deer Creek crossing, about 5 miles east of Lott, Falls County ( 12916) ; same road, 5 4/5 miles south by east of Deer Creek crossing ( 12917) . Navarro group, Nacatoch sand: Field 3/5 mile west of Kaufman (14103, 1 specimen figured). Navarro group, Corsicana marl: 2 1/5 miles north by east of Malta ( 12933, 16159, 1 specimen figured); % mile west of Kimbro (14129); Onion Creek, 21h miles east of old Garfield (7605, 14156); 2 miles east of Marion (Tex. Bu. 2395) ; near Camp Travis Hospital northeast of San Antonio (Tex. Bu. 39); arroyo 2/5 mile south by west of St. Mary's Univer­sity, Bexar County (Tex. Bu. 744); Cas­troville road, 1 1/5 miles west of Leon Creek, Bexar County (15522); 6 miles east of Castroville ( 15502) . Outside distribution. -A r k a n s a s: Brownstown marl, Ozan formation, An· nona chalk, Nacatoch sand. Tennessee: Coon Creek tongue of Rip· ley formation. Mississippi: Selma chalk, Coffee sand, Ripley formation, Owl Creek formation, Prairie Bluff chalk. Alabama: Tombigee sand member of Eutaw formation; Selma chalk (lower part). East-central Alabama and Chattahoochee region (Alabama-Georgia) : Blufftown formation, Ripley formation (upper part), and Providence sand. South Carolina: Peedee formation (up· per part). Maryland: Questionably in the Mata­ wan and Monmouth formations. Mexico: Cardenas beds, near Cardenas, State of San Luis Potosi. The University of Texas Publication No. 4101 Range.-Ranges through the zones of Exogyra ponderosa and E. costat,a; geo­graphically ranges throughout the Atlantic and Gulf Coastal Plain and into Mexico. HAMULUS SQUAMOSUS Gabb Pl. 4, fig. l 0 1859. Hamulus squamosus Gabb, Acad. Nat. Sci. Philadelphia Proc., vol. 11, p. 3. 1860. Hamulus squamosus Gabb, Acad. Nat. Sci. Philadelphia Jour., 2d ser., vol. 4, p. 398, pl. 68, fig. 45. 1921. Hamulus squamosus Gabb. Wade, U.S.Nat. Mus.Proc., vol. 59, p. 45, pl. IO, figs. 6, 7. 1926. Hamulus squamosus Gabb. Stephenson, Geol. Survey Alabama Special Rept. No. 14, p. 250, pl. 92, fig. 1. 1926. Hamulus squamosus Gabb. Wade, U.S. Geol. Survey Prof. Paper 137, p. 31, pl. 2, figs. 8, 13. 1929. Hamulus squamosus Gabb. Dane, Arkansas Geol. Survey Bull. 1, p. 150, pl. 27, fig. 1. Gahh's original description of this species is as follows: "H. squamosus n. s. This is a hamulus from Prairie Bluff [Alabama River, Wilcox County, Ala­bama], very closely allied to H. onyx, but differing in having a strongly marked raphe, which nearly doubles the width of the shell. It is placed on both sides and in the plane of the curve. Museum of Acad. of Nat. Sci." Tube small, regularly tapering, gen­erally strongly curved in early stages, straightening out in the adult stages; in­dividual variation in curvature marked; curvature generally in one plane, hut the tube may twist slightly out of the plane. Each tube hears 6 strong longitudinal ribs, two of which are modified to form thin broadly expanding more or less wavy wings or flanges with irregularly serrated outer edges; these may extend to the aper­ture, or may end, as such, one or more millimeters hack of the aperture; in the latter case, the continuation of the wings is represented by low ribs of normal as­pect which extend to the aperture. The winged ribs divide the other four ribs into two pairs; the ribs of each pair are mod­erately strong, with suhangular to sharply rounded crests which may he irregularly nodular, and the ribs of each pair are separated by a broadly V-shaped inter­space of moderate depth. Approximate dimensions of a medium· size Texas specimen: Length measured along the center of the tube around the curve, about 26 mm.; diameter at small end 1 mm.; diameter at large end 4+ mm.; maximum wing-spread 6.5 mm. The species is not common in the forma· tions of the Navarro group in Texas, but it occurs in great numbers in places in the Upper Cretaceous deposits of the Gulf Coastal Plain. Although always easily recognizable the species exhibits consid­erable individual variation in size, form, sculpture, degree of ruggedness, and de­gree of curvature. Types.-The original material, recorded as having come from Prairie Bluff, Ala­bama River, Wilcox County, Alabama, should he preserved in the Academy of Natural Sciences of Philadelphia, but is apparently lost. One lot in the Academy, labeled "types?" is recorded as having been received from "Dr. Spillman, Mis­sissippi"; the lot includes 5 tubes, 4 of which are referable to H amulus squamosus Gahh, and one to H. onyx Morton. Plesio­type. from Texas, U.S.N.M. no. 76274. Distribution in Texas.-Taylor marl: Burlington road, 2 3/10 miles west-south· west of Rosebud, Falls County (14135); old highway, westward-facing slope of Little Walnut Creek valley, about 2 miles southwest of Sprinkle, Travis County (14160); right hank of a small arroyo, 2~ miles south of San Marcos, 1/3 mile east of the San Marcos-Staples store road, Hays County (7617). Upson clay: ?Core sample taken at a depth of 2450 feet in a test well in sec­tion 116, Maverick County (10286). Navarro group, Corsicana marl: 2 3/5 miles north by east of Malta (16159) ; 5 miles southwest of Quinlan (15546) ; Onion Creek 2~ miles west of old Gar­field ( 14156, 15532) ; Castroville road, 1 1/5 miles west of Leon Creek, Bexar County ( 15522) ; 14 miles west of San Antonio ( 15520) . Navarro group, Kemp clay: 2 miles northwest of Deatsville (14128). Outside distribution. -A r k a n s a s: Brownstown mar1, Ozan formation An­nona chalk. ' Invertebrate Fossils of the Navarro Group Tennessee: Coon Creek tongue of Rip­ ley formation. Mississippi: Coffee sand, Selma chalk (lower part and Exogyra cancellata zone) , Ripley formation, and Prairie Bluff chalk. West-central Alabama: Selma chalk (lower part) . East-central Alabama and Chattahoochee region (Alabama-Georgia): Blufltown formation, Ripley formation (upper part) , and Providence sand. Range.-Exogyra ponderosa and Exo­gyra costiJta zones of Gulf Coastal Plain. HAMULUS? HUNTENSIS Stephenson, n.ap. PI. 4, figs. 11-16 Tube large, thick-walled, tapering gradually. Surface badly corroded in the available material, the jagged edges of the growth layers forming irregular transverse lines about the tube. The tube is made up of a succession of gradually enlarging, truncated cone-shaped layers, the outer ends of which bend back as in the genus Hamulus; the bent-hack ends of these lay­ ers were largely destroyed by corrosion, apparently h e f o r e fossilization, hut enough of the tube has been preserved to show this feature in places. There is no suggestion of longitudinal ridges. The small end of the tube is not pre­served, hut all of the longer fragments show curvature in one plane, which in­creases toward the small end. The small­est measured diameter is 4.2 mm., and the largest diameter 19 mm. The dimensions of the longest fragment are: Length 62 mm.; diameter at small end 8 mm.; diameter at large end 12.4 mm.; maximum thickness of tube wall 3 mm. The maxi­mum thickness of shell wall noted in the collection is about 4 mm. The reference of this species question­ably to Hamulus is based on the reflected outer ends of the growth layers, the gen­tle curvature, and the gradual tapering of the tubes. The species appears to be closely re­lated to the large species, H amulus walk­erensis Stephenson, from the Snow Hill member of the Black Creek formation of North Carolina, but it lacks the 6 faint longitudinal swells which on the North Carolina species correspond to the 6 ribs of other species of the genus. Too much dependence should perhaps not he placed on the reflected growth lay· ers in the determination of the genus H amulus, for this feature is known to oc­cur in irregularly sinuous, unrihbed ma­rine tubes, as for example, in the Recent Crucigera formosa Bush, which inhabits the waters of Japan. Types.-Five figured cotypes, U.S.N.M. no. 76275; 13 unfigured cotypes, U.S.N.M. no. 76276. Distribution in Texas.--Navarro group, Nacatoch sand: I 1h miles west of Camp­bell ( 12925) . Navarro group, Corsicana marl: ? Field I 9/10 miles northeast of Quinlan (17381). Phylum ECHINODERMATA Subphylum PELMATOZOA Class CRINOIDEA Order ARTICULATA Family BOURGUETICRINIDAE This group of organisms is represented by two small segments of stems or roots, from the Corsicana marl in a dug well at a windmill, 0.35 mile south by west of St. Mary's University, just south of Culehra road, . Bexar County (16353, U.S.N.M. no. 76277). One fragment is 3.7 mm. long, 2 mm. in diameter, and is com­posed of three segments; the sides of 'the segments are smooth but are slightly and broadly concave between the joints; the joint surfaces are circular with a small central perforation; they appear smooth hut under a lens are slightly undulating in detail and are very finely granular. The other fragment is similar to the first and appears to he one segment 3 mm. long and 2.3 mm. in diameter. These frag.. men ts have been examined by Dr. Edwin Kirk, who furnishes the foliowing note: The fragments are identical in appearance with material from the Prairie Bluff chalk in Chicka­saw County, Mississippi, where a remarkably com­plete lot of crinoid remains was obtained in June 1936 by L. W. Stephenson and W. H. Monroe. The material from Mississippi includes complete roots and crowns, together with a large amount of fragmentary columns. The crinoid represents The University of Texas Publication No. 4101 a new genus, the nearest affinities of which seem to be with Mesocrinus from the Cretaceous of Sweden. Subphylum ECHINOZOA Class ECHINOIDEA Order CIDAROIDEA Family CIDARIDAE One well preserved spine, probably a cidarid (pl. 5, fig. 3) , was found in the Nacatoch sand in a bluff on Red River, 200 yards west of Lewis Ferry, 8 miles north of New Boston, Bowie County ( 12935, U .S.N .M. no. 76278) . The spine is long, slender, and tapering above, and the shaft is ornamented with longitudinal rows of prominent closely spaced tuber­cles; on the lower part of the shaft the . rows number 8, hut toward the top there are 10 rows due to the intercalation of two additional rows in two of the inters paces; a few small to medium sized tubercles oc­cur at scattered intervals elsewhere in the interspaces. The base of the spine is incised where it was seated on its tubercle; a sharp finely serrated ridge girdles the spine about one millimeter above the basal terminus, and below the ridge the base is strongly beveled; just above the ridge a slightly sunken, finely cross-striated hand, about half a millimeter wide, en­circles the lower end of the shaft. A small fragment of a cidarid test found in the Corsicana marl in a dug well at a windmill, 0.35 mile south by west of St. Mary's University ( 16353), is not ade­quate for generic and specific identifica­tion. Order EXOCYCLOIDA Suborder SPATANGINA Tribe SPATANGOIDEA Family ANANCHYTIDAE Genus CARDIASTER Forbes CARDIASTER LEONENSIS Stephenson, n.sp. Pl. 5, figs. 4-7; pl. 6, figs. 5, 6 Test small, cordate, of medium height, a little flattened in the apical region; a lateral cross section through the apex pre­sents a nearly uniformly curved arch, slightly flattened, however, at the top. The test is widest anteriorly, becoming slightly constricted posteriorly. Base concave an­ teriorly with a broadly arched plastron extending with increasi~g width .from ~e peristome to the posterior mar~m, which is slightly truncated; the posterior ambu­lacra occupy the shallow, radiating de­pressions on either side of the plastron. The amhulacra are of only moderate width and are suhpetaloid, the pore-pairs dying out well above the ambitus; the pores are small, slightly elongate, uniserial in ar­rangement, and the pores of each pair are suhequal and closely spaced; the pore. pairs appear to be nonconjugate. Only the anterior amhulacrum occupies a sulcus. The amhulacral plates are small and nar· row and each pore-pair is situated cen· trally with respect to the length of the plate, hut nearer the lower edge. The sulcus occupied by the anterior ambula· crum is shallow, is widest and deepest at the amhitus, an~ narrows and practically disappears before reaching the apical sys­tem; it is bordered by rounded edges; the pore-pairs can only he faintly seen in this ambulacrum. The anterolateral pair of amhulacra are slightly longer than the posterolateral pair, and they bend slightly forward toward their dorsal ends; at the outer end of the petals the pore-pairs in the two series are about equal in size, hut dorsally the pores in the anterior row be­come progressively smaller than those in the posterior row, and practically disap­pear before reaching the dorsal end of the amhulacrum. The posterolateral pair of ambulacra is similar to the antero· lateral pair; in this case also the dorsal end of each ambulacrum bends slightly forward, and the pores in the anterior row become smaller toward the dorsal end. The interamhulacral plates are propor· tionately large, their height being two to four times that of the nearest ad{"acent amhulacral plates; the height of the arger ones ranges from one-fourth to one-third the length. The apical system is situated at about the center of the test, and has the elongate arrangement of the plates characteristic of the genus. From hack to front the sue· cession of plates is: (1) The two oculars · of the posterolateral ambulacra, with inner sides in contact; (2) two genitals in contact; ( 3) the two oculars of the an­terolateral amhulacra, with sides in con­tact; ( 4) two genitals in contact, the larger one on the right being the madreporite; Invertebrate Fossils of the Navarro Group and (5) the oculars of the anterior amhu­lacrum. The pores of these plates are not visible in the one available specimen. The surface of die madreporite is slightly tumid. The peristome is rather small, and broadly ovate, and is situated well toward the front of the base. The ha~e is largely covered with matrix in which are embedded numerous small slender, prostrate spines, one of which is 4 mm. long. The other features of the base are con­cealed by the matrix. The periproct is of medium size, nearly circular, and situated somewhat above the ambitus on the upper end of a small, nearly vertical, triangular. truncate terminal surface of the test. The surface of the test bears scattered small primary and secondary tubercles and many tiny, intermediate miliaries; each primary consists of a narrow, slightly raised boss, surmounted by a proportion­ately large, broadly rounded mamelon; slightly sunken scrobicules may he de­tected encircling some of the tubercles; microscopic granulations cover the inter­mediate surface; a faintly developed fas­ciole passes horizontally beneath the peri­proct, and dies out 7 or 8 mm. on either side of that opening; this is the principal character which distinguishes this genus from Holaster. Dimensions of the holotype: Length 16 mm., width 16 mm,, height 8.25 mm. Card'iaster curtus Clark,86 from the Fox Hills sandstone, 25 miles southwest of Mingusville, Montana, is a nearly related species, but it appears to be proportion­ately higher, the sulcus occupied by the anterior amhulacrum is deeper and more sharply outlined, and the ambulacral areas are proportionately larger. Cardiaster smocki Clark,87 from the Merchantville clay near Matawan, New Jersey, is comparable in size and general form to C. leonensis, hut its poor state of preservation scarcely permits a critical comparison. Cardiaster marylandica Clark,88 from the Monmouth formation at Brightseat, Maryland, although imperfectly preserved, 141Clark, W. B.• U. S. Geol. Survey Mon., vol. 54, p. 84, pl. 37, figs. la·h. 1915. • Clark, W. B. (in Weller), Geol. Survey New Jersey, Paleontology, vol. 4, p. 298, pl. 13, 6p. 9·11, 1907. • Clark. W. B. (:n Gardner'• chapter), Maryland Geol. Suney, Upper CNtaceou1 (2 vole.), p. 750, pl. 47, figs. 45·10, 1916. appears to have a deeper anterior am­hulacral sulcus, and wider ambulacral areas, and the pores in each pair are wider apart than in the Texas species. Holotype.-U.S.N.M. no. 76279. Distribution in Texas.-Navarro group, Corsicana marl : Castroville road, 1 1 /5 miles west of Leon Creek, Bexar County (15522). Family SPATANGIDAE Cenua HEMIASTER Deaor89 Type species, by subsequent designation.90-Spa­tangus bu/o Brongniart.91 As used by the present author the genus Hemiaster Desor includes those species of the family Spatangidae having a peripet· alous fasciole and lacking other fascioles. The genus has been divided by authors into subgenera and sections, and some of the subgenera have even been raised to the rank of genus, but for the present no attempt will be made to place the Navarro representatives of Hemiaster in these sub­divisions. HEMIASTER DALLI Clark Pl. 6, figs. 1-4 1891. Hemiaster dalli Clark, Johns Hopkins Univ. Circ., vol. 10, no. 87, p. 77. 1893. Hemiaster dalli Clark, Johns Hopkins Univ. Circ., vol. 12, no. 103, p. 52. 1893. Hemiaster dalli Clark, U.S.Geol. Survey Bull. 97, p. 89, pl. 48, figs. 2a-e. 1915. Hemiaster dalli Clark, U.S.Geol. Survey Mon., vol. 54, p. 90, pl. 47, figs. la-f. 1924. H emiaster ( Proraster) dalli (Clark) . Lam­ bert and Thiery, Essai de nomenclature raisonnee des echinides, Fasc. 6 et 7, p. 506. 1926. Proraster dalli (Clark). Lambe·t, Bull. Soc. Geol. France, 4th ser., Tome 26, p. 273. 1928. Proraster dalli (Clark). Adkins, Univ. Texas Bull. 2838, p. 300. Test of medium size and height, broadly suhovate in ambital outline, slightly sub­truncated on the posterior and postero­lateral sides; the test is widest in a cross 89Agaa1iz, M. M. L. et Desor. E., Catalogue raisonne de• e1pece1 de1 genres et de1 families d'cchinides: Ann. sci. oat., troiaiemo aer1o. Partio Zool'Ogique, Tome 8, p. 16, pl. 16 (in Tome 6), fi1, 7, 1847. '°Lambert, ]., and Thiery, P., Essai de nomenclature raiaonneo des echinides, Fascioles 6 et 7, p. 499, 1924. 91.Cuvier, G., and Brongniart, A., Description geologique dea environs de Par~e-Descript:on des vegetaux du terrain do 1ediment 8uperieur, cites dan1 la description geologique du ba91in de Paria, par A. Brongniart, p. 389, pl. 5, figs. 4A·C, 1822. The University of Te:cas Publication No. 4101 section slightly in front of the apex. The apex is strongly acentric, the ambulaera very unequal, the petals set in deep de­pressions between prominent ridges. A rather prominent keel rises back of the apex between the ri~ht and left po~tero­lateral ambulacra. Base broadlv conwx, peristome far to the front. Ant~rior am­hulacrum profoundly sunken. subpetaloid, the petal long and broad: the furrow pro­duces a deep notch in the anterior margin. Plates of petal Ion~. narrow. numerous, with pore-pairs within less than a milli­me~er of the ends, producing a very wide interporiferous area: pore-pairs strongly inclined. arranged in uniserial rows: the pores of each pair are small, circular to ovate. and onlv about half a millimeter apart,; the two ·rows of pore-pairs seem to end at the edge of the ambital notch. The anterolateral ambulacra are petal­oid, the petals extending about two-thirds of the distance to the ambitus; the petals are moderately broad and bend strongly forward as they approach the apex; the plates of the petals are narrow; the pore­pairs are uniserial, the pores of each pair being elongate, wide apart and conjugate; the interporiferous area is a little wider than the length of one pore-pair; the an­terior row of pore-pairs becomes much narrower than the posterior one as it approaches the apex. The posterolateral ambulacra are like the anterolateral ones, but the petals are only a little more than half as long, are scarcely curved, and the rows of pore-pairs are nearly equal in width. The plates of the ambulacra be­tween the lower ends of the petals and the peristome are much larger and more irregular than those in the petals them­seh-es, and pore-pairs are obscure or ab­sent: pore-pairs in longitudinal instead of transverse arrangement can be seen on several plates of the anterolateral am­hulacra on the wntral side of the test near the mouth. The interambulacral plates are proportionately very large. The peripetalous faseiole is complete and narrow, with a noticeable subangular sinu­osity just back of each anterolateral am­bulacrum, and with mmor sinuosities elsewhere. The plates of the apical system are not clearly exposed. but the genital pores are lar~e. the two on either side being close together, and the pairs thus formed are widely separated from each other. T~e peri~tome is small, transversely oval, sit­uated far forward in a shallow depression just below the ambital notch, and is bor­dered on the posterior side by a prominent, overhanging, carinoid lip. Periproct small, ovate, situated high above the am­bi tus at the upper end of a broad shallow nearly vertical concavity. The surface is irreg~larly covered with tubercles, includ­ing primaries, secondaries and miliaries. The primaries are coarsest and most densely spaced on the ambitus on either side of the notch formed by the anterior ambulacrum; the fewest and smallest tu here les are on the posterolateral am­bulacra both on the lower and upper side of the test; the actinal portions of the posterolateral ambulacra are finely granu­lated with only a few scattered tubercles; the under side of the test at the center of each side just below the ambitus is also nearly bare of tubercles. A fully developed primary consists of a rather prominent crenulated boss, surmounted by a tiny perforated mamelon, and sur­rounded by a more or less completely developed, slightly sunken scrobicule. Dimensions of the specimen shown in plate 6, figures 1-4: Length 25 mm., width 25 mm., height 14 mm. Hem foster dalli Clark is recorded as having been found in the Washita group of the Comanche series in Bexar County, Texas. The description given above is based on a smaller but more complete specimen from the Corsicana marl in ·Bexar County. No essential difference can be detected between this specimen and the holotype of H emiaster dalli, and this close correspondence strongly suggests that the reported occurrence of the latter in the Washita group is an error. Additional data tending to confirm this error are contained in the report of Mr. L. G. Hen· best, micropaleontologist of the Geological S~rv.ey. on a sample of matrix dug from w1thm the test of the holotype. He says: I removed a small amount of chalky matrix from the holotype of Hemiaster dalli Clark (U.S. N.M.no. 19ll4) and disintegrated the chalk as well as I could. but was not sncTessful in obtain­inl! well-cleaned specimens of Foraminifera. As a co?seq~enc~. co~siderable uncertainty enters my specific 1dent1ficat1ons and the conclusions as to the real age of the Hemia.ster specimen. Invertebrate Fossils of the Navarro Group In proportion to the si7.e of the sample, .A.noma­lina and Guembelina are numerous. All of the Anomalinas are minute. One of the largest speci­mens agrees rather closely in size and also in form with A. in.voluta (Reuss). The Guembelina are probably G. globulosa (Ehrenberg) and G. &triata (Ehrenberg). The two specimens which were assigned to the latter species were plainly striated and had the general si7.e and form of G. &triata, but I could not determine whether the striae are continuous or interrupted at the sutures. A few specimens of Globigerina and one of Frondicularia archiaciana D'Orbigny were found. This micro-fauna strongly suggests Upper Cre­ taceous age and most probably is Austin or younger. In the first of Lambert's two papers (1924) cited in the synonymy he listed this species as an example of Proraster, treating Proraster as a subgenus of Hemi­Glter, and in the second paper (1926), he treated Proraster as a genus. Proraster was first proposed as a genus by Lamhert92 in 1895, at which time he listed as examples the three species, Spa1angw lacunosus Goldfuss, Schizaster and,quu1 Cotteau, and Schizaster atavus Arnaud. In 1924, Lambert and Thiery (ae synonymy) state that the first two of these three species were shown by Schluter and Gouthier to possess lateral fascioles, which would rule them out of Proraster, leaning Schizaster atavus Arnaud as the aole type of Proraster. Hemiaster da/,li Clark is strikingly like Sciiza.tter atavus Arnaud,93 as the latter i8 figured in the original description and tile two species appear to belong to the same group. Since Hemiaster forms a compact group characterized by a peri­petalous fasciole, it seems desirable, for the present, at least, to retain that name for the group as a whole and to classify its subgroups, if any, as subgenera. If Prora&ter is to be recognized as a distinct group, it would therefore seem appro­priate to treat it as a subgenus of Hemiaster, and H. daUi Clark would seem to he a good example of the subgenus. tltunhert, If. J•• Essai d'une monognphie du genre JDloruter et notes aur quelques echinides. Publ"ahed in C...O.ne, A. de, R~hercha ar la Craie Superieure: 11"8oires pour eenir a l'Explicatioa de la Carte CCologique Delaillee de la France. Fascicule 1. pp. 177. 256, 1895. -COtteaa. M. G., Echinidee Jara•iques, Cretaces et Tertialre. du sud-oueat de la France: Ann. Soc. Sci. nat. • la Rochelle. p. 223, pl. 12. fip. 5-9. 188.l. (The author­elalp of SclmMter .,..,.., is attributed to Arnaud.) Schizaster at,avus Arnaud is recorded from the upper Senonian of western France. Types.-·Holotype, U.S.N.M. no. 19114; the new material includes one nearly per­fect specimen ( plesiotype, pl. 6, figs. 1-4) , and two imperfect, unfigured specimens (U.S.N.M. no. 76280). Distribution in Texas.-Navarro group, Corsicana marl: 6 miles east of Castro­ville (15502, one specimen figured); the holotype came from somewhere in Bexar County. HEMIASTER BEXARI Clark Pl. 6, figs. 7, 8; pl. 7, figs. 5-7 1915. Hem.iaster bexari Clark, U.S.Geol. Survey Mon., vol. 54, p. 89, pl. 46, figs. la-e. 1924. H emiaster ( Leymeriaster) bexari (Clark) . Lambert and Thiery, Essai de nomencla­ture raisonnee des echinides, Fasc. 6 et 7, p. 500. 1926. H emiaster ( Leymeriaster) bexari (Clark) . Lambert, Bull. Soc. Geol. France, 4th ser., Tome 26, p. 273. 1928. H emiaster ( Leymeriaster) bexari (Clark) . Adkins, Univ. Texas Bull. 2838, p. 298. Test of medium size, rather high pos­teriorly, a little flattened anteriorly, broadly subovate in ambital outline, wid­est centrally. Apex acentric, situated about three-fifths the length of the shell from the anterior end. Ambulacra un­equal, all set in shallow furrows. Base broadly convex with the posterolateral am­bulacra occupying shallow depressions on either side of the plastron. Petal of an­terior ambulacrum long, broad, and oc­cupying a flat-bottomed furrow which fades out anteriorly, and is only faintly reflected in the ambitus; plates of petal of medium length and height; pore-pairs oblique, situated near the ends of the plates in uniserial rows, the pores of each pair small and separated by a prom­inent tubercle, thus producing a row of tubercles on either side of the petal; the plates of this ambulacrum between the petal and the peristome are about 16 in number, are proportionately larger, ir­regularly 5 or 6-sided, with their greatest elongation in the linear direction of the ambulacrum. The petals of the antero­lateral ambulacra are wide, about as long as that of the anterior ambulacrum, and are composed of numerous long narrow The University of Texas Publication No. 4101 plates, each only about half as wide as a corresponding plate on the anterior am­bulacrum. The pore-pairs are uniserial, the pores of each pair being circular to broadly ovate, widely separated, and con­nected by a narrow ridge instead of a furrow; the interporiferous area is about one-fourth the total width of the petal; the anterior row of pore-pairs in each petal becomes very narrow as it ap­proaches the apex. The plates of an an­terolateral ambulacrum between the petal and the peristome are proportionately large, 5 to 6-sided, with a tendency to elongation in the linear direction of the ambulacrum; the ambulacral band is strongly constricted and the plates are small just below the end of the petal, but the band quickly widens downward and at the ambitus is about as wide as the petal; the band narrows a little as it ap­proaches the peristome. On 7 or 8 of the plates nearest the peristome small pore­pairs appear near the center of the for­ward end of each plate; the pores of each pair are aligned in a direction linear to the band. The petals of the posterolateral ambulacra are similar to those of the anterolateral pair, but are only a little more than half as long and the rows of pore-pairs are nearly equal. The plates of the ambulacral band between the petal and the peristome differ markedly in size and shape; the band is sharply constricted just below the end of the petal, where the plates are small; between this constriction and the ambitus the plates are larger and the band widens out, becoming at the ambit us a little wider than the petal; be­tween the ambitus and the peristome the hand becomes narrower and the plates larger, fewer, and greatly elongated. The interambulacral plates range from small near the apex and peristome to very large at the ambitus; they are relative} y few in number. The apical system is typical of the genus. The oculars are perforated; the two oculars adjacent to the posterolateral pair of ambulacra are in contact with each other but the other three oculars are isolated by the genital plates. The four genital plates are conspicuously perfor­Dted and form a compact system; the madreporite is larger than the other three genitals and is in contact with all of them anld Mu~. Nat. Hi~t. Puh. 13-1. Ceol. ~er.. ml. -1. no. I. pp. 12-J.l. pl. 3. fig~. 1-11. , 1915. Linthia rariabilis Sloeurn. Clark. U.S.Geol. ~urvey !\Ion .. ml. 5-1. pp. 99-100. pl. s.i. fil!<;;· la-1. 19:27. Linthia mriabilis Slocnm. Stt"phen~on. U.S. Nat.1\111~.Proc.. ml. 72, art. IO. p. 10, pl. 5. fi~~. 1-7. Tlw arnilable adult Texas specimens in­cl udc 7 crushed and more or less incom­plete tests. The features which are well enough preserved for comparison appear to agree closely with typical specimens from Pontotoc. Mississippi, the type local­ity of the species. These features include size, character, and distribution of tubercles, length, width, and depth of ambulacral furrows, character and ar­rangement of the pore-pairs, position of peripetalous and lateral fascioles, and height and farm of the ridge separating the posterolateral ambulacra. As all these adult Texas specimens have been badly crushed it is not possible to make a criti­cal comparison of form. Although the Texas specimens can not be accurately measured, the average size is probably about the same as those from Mississippi, which range up to a length of nearly 32 mm. One small fairly well preserved speci­men. shown in plate 8, figs. 3-5, may be the young of this species. It measures: Length 16 mm., width 16.5 mm., height ll mm. Slocum's description of this species is quoted by Clark in U.S. Geol. Survey Mon., vol. 54, pp. 99-100, 1915. A closely related undescribed species ocrnrs in the :\"acatoch sand of Arkansas. Types.-~ine existing cotypes are in the custody of the Field Museum of Natural History, Chicago. These bear the follow-in~ catalogue numbers: Pl0457A, Pl0-157D, Pl0457H (?), Pl0457K (?) Pl0-158L (Slornm's plate 3, figs. 5-8), Pl045ff\1I. Pl0458N, P10458 1 ?letter). Other cotypes mentioned by Slocum are "pparently no longer preserwd in the F;icld :\I useum. One plesiotype? from Texas, U.S.N.M. no. 7628~; 2 plesio· types? from Texas, U.S.N.M. no. 76284. Slo<'lltn says: "This species is from the Riplf•y ~roui> [Prairie Bluff chalk] and is quite abundant both on the bluffs of One Mile Run and near the southern edge of the village of Pontotoc, Mississippi." He does not indicate at which of the two localities the different numbered specimens were collected. Distribution in Texas.-Navarro group, Corsicana marl: 2% miles west of Mc­Queeney ( l 5523) ; 6 miles east of Castro· ville 06156). 0 u t s id e distribution. -Mississippi: Prairie Bluff chalk and Owl Creek forma· ti on. North Carolina: Upper part of Peedee formation. LINTHIA? sp. The Kemp clay exposed on Colorado River at Webberville, Travis County (7601), yielded several small fragments of an echinoid which may be a Linthia. Genus MICRASTER Agassiz102 Type species.-Spatangus coranguinum Klein.103 Subgenus PLESIASTER Pomel The subgenus Plesiaster Pomel1°4 (geno· type, Micraster peinei Coquand) ,1°5 dif· f ers from the typical M icraster in the pos· session of a peripetalous fasciole, in addi· tion to the characteristic subanal fasciole. 102A!!assiz. L.• Prodromc d'une monographie des radiaire1 ou echinodcrm"s: Soc. sci. nat. de Neuchatel Mem., tome 1, p. 181. 1836. Agassiz. L.. rt Dr!lor. E.. Anns. sci. nat., 3d eer., Zoologie, tome 8, p. 23. pl. 16, fig. 5 (in tome 6), Pari1, 18H. Pomrl. ~. A., Classificat:on mcthodique et Genera de1 echinides vivants et fossilcs: Theses prcsentees a la Faculto des Sciences de Paris, p. 42, Alger, 1883. Lambert. J•. and Thiery, P ., Essai de nomenclature raisonnce des cchinides, Fasc. 6 ct 7, p. 1179, 1924. io:1Kl<'in, Jacobi T., Naturalis dispositio echinodermatum, p. 28, tom,• 23. figs. A·D, 1731. ---. ---. Ordre natural des oursins de mer; ed. Gall.. p. 100, pl. 12, figs. E. F; pl. 13, fig. C, 1754. ---. ---. l\aturalis dispositio echinodermatum (t'ditt'd and C'Xpanded hy Nathanaelc G. Leske): pp. 28, 221. pl. 23. figs. A-D; pl. ~3x, fig. C; pl. 45, fig. 12, 1778. 10~Pomel. !';. A., op. cit., p. 42. lOSCoquand, H., Synopsis des fos!liles de la region sud de la province de Constant'nc, Algeria: Soc. d'Emulation de Constantine Mc·m., p. 2·'15, pl. 27, figs. 1·3, 1862. Invertebrate Fossils of the Navarro Group MJCRASTER (PLESIASTER) AMERICANUS Stephenson. n.sp. Pl. 7, figs. 1-4 Test of medium size, rather high, elon­gate-cordate, truncated on the posterior end, widest a little in advance of the mid­length, highest posteriorly. Apical sys­tem situated slightly back of the mid­length. Petals moderately sunken, the an­terior one making a broad, shallow notch in the amhitus. The elevation between the posterolateral ambulacra is rounded and a little higher than the other inter­ambulacral areas. Base slightly convex, the plastron being plumply swollen to­ward the rear, with several low nodes near the ambitus; a nearly vertical row of three obscure nodes borders either side of the posterior truncation. The peristome is situated well forward, and the peri proct is high on the porterior truncation. An­terior ambulacrum subpetaloid, sunken to form a broad sulcus of moderate depth, broadly rounded on the bottom; plates of petal elongated and less than half as wide as long; the rows of pore-pairs are uni­serial and wide apart; the pores of each pair are close together, oblique, separated by a node, the outer one apparently larger than the inner one; the pores appear to die out about two-thirds of the distance from the apical system to the ambitus. The anterolateral ambulacra are sub­petaloid, the petals being about as long as that of the anterior ambulacrum, but they are narrower; the plates are numer­ous, long and narrow, being only about half as wide as those of the anterior petal; the pores of each pair are elongate and wide apart, and the pairs are arranged uniserially; although the surface is dam­aged by cleaning, the pores appear to be conjugated; the interporiferous area is a little wider than either pore zone; the pore zones are unequal, the anterior one becoming narrower toward the apex than the posterior one. The petals of the posterolateral ambulacra are similar to those of the anterolateral pair except that they are shorter and narrower, and the pores are more nearly equal; the posterior pore zone is, however, straighter than the anterior one. The plates of the ambulacra below the ends of the petals are scarcely well enough exposed for accurate descri p· tion, but the posterolateral ambulacral bands are sinuous and of unequal width between the ends of the petals and the peristome, and the plate~ are consequent!y of irregular size and shape. A character­istic subanal fasciole forms an ovate ring, half of which is on the actinal surf ace, and the other half on the posterior end of the test above the ambitus. There is in addition a fairly distinct and complete peripetalous fasciole, a feature which seems to place this species in the subgenus Plesiaster Pomel. The apical system is not well exposed, but the four genital pores are large and close! y grouped, and the madreporite is proportionately small. The peristome is small, transversely elongated, bears a rather prominent carinated under Iip, and occupies a shallow depression in the base. Periproct small, ovate, situated high on a nearly vertical posterior truncation. The surface of the test bears a rather scattered assemblage of tubercles including pri­maries, secondaries, and miliaries. The better preserYed tubercles consist of a prominent boss finely crenulated above, surmounted by a small perforated mame­lon, and surrounded by a narrow, sharply outlined, but scarcely sunken scrobicule. The tubercles are coarsest on the anterior end of the test and on the forward part of the under surface; they are finest on the posterior end of the test; on the under surface the irregular hands marking the position of the posterolateral ambulacra are granulated and nearly devoid of tubercles. The whole surface of the test, where well preserved, is seen to be cov­ered with microscopic granules. Dimensions of the holotype: Length 30 mm., width 26.5 mm., height 19.5 mm. This species is represented in Texas by one well preserved specimen, and by one other questionably identified specimen which appears to be abnormally swollen by oxidized marcasite within the test. A related, hut large, undescribed species oc­ curs in considerable numbers at several localities in the Saratoga chalk of Arkan­ sas. These, the Alabama locality, and the two Texas localities recorded below are The University of Texas Publication No. 4101 the only known occurrences of Micraster in the Americas. M icraster maestrichtensis Lambert from "la Craie de Maestricht," in the Maestricht district, Netherlands, is more broadly ovate in outline, lacks a peripetalous fasciole, and only 3 of the 4 genital plates are perforated. Holotype.-U.S.N.M. no. 76285. Distribution in Texas.-Navarro group, Corsicana marl: 6 miles east of Castro­ville ( 15502, type locality) ; 2 miles south of Cliff ( 10870) . OutsUle distribution.-Alabama: Ques­tionabJ y in the Prairie Bluff chalk at Prairie Bluff, Wilcox County, Alabama. Phylum MOLLUSCOIDEA Class BRACHIOPODA Order A TREMATA Superfamily LINGULACEA Genua UNGULA Bruauiere LINGULA aff. L SUBSPATULATA Hall and Meek Pl. 3, figs. 7-9 Shell small, elongated, compressed, pol­ished. Posterior extremity sharply rounded, scarcely pointed. The growth lines indicate that in its earliest stage the outline of the shell is nearly circular, but as growth proceeds new shell substance is added more rapidly on the anterior mar­gin than on the sides, causing the sides to become proportionately elongated, sub­parallel, and nearly straight; the growth lines remain broadly rounded anteriorly for 4 or 5 mm. from the beak, beyond which they gradually become straighter, producing a subtruncated anterior extrem­ity in the adult. The shell is very broadly subangular on each side where the pos­terior margin passes into the lateral mar­gins. The 5 available specimens from Navarro County indicate considerable in­dividual variation in outline, some speci­mens being proportionately broader than others; of two specimens, each about 5 mm. long, one is 2.5 and the other 3.1 mm. wide. The beak appears as a low, ob­scure, somewhat irregular knob, very slightly in advance of the posterior ex­tremity. In addition to the fine growth lines the polished surface is further marked with very fa int, fine radiating striae. Approximate dismensions of the larg· est specimen: Length 7.5 mm.; width 3.7mm. The original description of the species is based on an incomplete shell from the Pierre shale near Red Cedar Island, Mis· souri River, 35 miles below Fort Pierre, South Dakota. The beak is wanting and the margins are broken away in this speci· men. The shell is similar but is propor­tionately broader than the ones from Texas and is more than twice as large. The shells described by Weller, under this name, from the Woodbury clay, New Jersey, are nearly identical in outline with the Texas specimens, but they attain a maximum measured length of 19 mm. Types.-The types of Hall and Meek's species, Lingula subs patulata, were originally the personal property of Hall, and were later purchased from him by the American Museum of Natural History, New York, where they are now preserved (No. 93{° ) . Three plesiotypes from Texas, · U.S.N.M. no. 76286. Distribution in Texas.-Navarro group, N acatoch sand: Road 2 miles southwest of Kaufman (7546). Navarro group, Kemp clay: 3% miles northwest of Bazette (12922, loc. of plesiotypes) . Order TELOTREMA TA Superfamily TEREBRA TULACEA Family TEREBRATULIDAE Genus TEREBRATULINA d'Orbiany TEREBRATULINA NOAKENSIS Stephenson, n.1p. Pl. 3, figs. 10-12 Shell small, longer than wide, moder· ately thick, dorsal valve flatter than ventral valve, median sinus wanting. Posterior extremity subpointed with pos· terior margins nearly straight and diverg· ing at an angle of about 72 degrees. An· terior. ~xtremity evenly rounded forming a semicircle. Beak of ventral valve rising well above the posterior margin of the dorsal valve. Foramen circular, moder.. ately large, slightly open on the hinge line. Surface of both valves crowded Invertebrate Fossils of the Navarro Group with fine, distinct but nonprominent, closely spaced ribs of somewhat irregular sizes; ribs few near the beak, increasing in number by intercalation at differing distances away from the beak in such a manner that about the same degree of crowding is maintained, and permitting little if any increase in the size of in­dividual ribs in the anterior direction. The holotype, the only available specimen, is mechanically slightly compressed and is partly broken away on one side. Enough of the loop is in view to show that it is short as it should be in this genus, but it can not be observed in detail. Dimensions: Length 15.4 mm., width 12 + mm., thickness 5.6 mm. Compared with TerebratuUna brew­&teren.si& Adkins108 from a clay bed of Taylor age, on the Alpine-Brewster road 14 miles north of Terlingua, Brewster County, Texas, this species is larger, pro­portionately longer, has noticeably coarser ribbing, and lacks a median sinus. The species is much larger and propor­tionately longer than T. filosa Conrad, de­scribed from the Selma chalk (Exogyra ponderosa zone) , Alabama, and common in the Pecan Gap chalk member of the Taylor marl in Texas. Holotype.-V.S.N.M. no. 76287. Distribution in Texas.-Navarro group, Kemp clay: 3 miles S. 30° W. of Thrall (17370). Phylum MOLLUSCA Class PELECYPODA Order PRIONODESMACEA Superfamily SOLEMY ACEA Family SOLEMYACIDAE Geaua SOLEMYA Lamarck SOLEMYA BIUX White? PL 8, fig. 6 1880. Solemya bilix White, U.S.Nat.Mus.Proc., vol. 3, p. 158. 1881. Solemya bilix White, U.S.Nat.Mus.Proc., vol. 4, p. 139, pl. 1, fig. 9. 1920. Solemya bUix White. Stanton, U.S.Geol. Survey Prof. Paper 128, p. 19, pl. 1, figs. la, lb. •AdkJn11 W. S., Somo Upper Cretaceous Taylor am· moalte1 from Tena: Univ. Texa1 Bull. 2901, p. 211, pl. 6. Ip. 1-6, 1929. This rare genus is represented in the Nacatoch sand by one internal mold which lacks the surf ace ornamentation necessary for certain specific determination; it is ref erred questionably to White's species Solemya bilix. The shell is greatly elongated, moder­ately convex, strongly inequilateral, with the anterior end much the longer. Beak broad, low, apparently opisthogyrate, sit­uated about one-fourth the length of the shell in advance of the posterior extrem­ity. Hinge not revealed. Anterior ad­ductor scar obscure. Posterior adductor scar of moderate size, subtrigonal, bor­dered in front on the mold by a radial groove representing an internal rib. An­terodorsal margin long, very broadly arched, closely paralleled by a relatively broad, shallow groove; anterior margin sharply rounded; ventral margin nearly straight, rising a little posteriorly; pos­terior margin more sharp Iy rounded than the anterior; posterodorsal margin short, slightly arched. Surface obscurely marked by fine radiating lines which become coarser anteriorlv. The double­threaded character of ~the radial or­namentation expressed in the specific name bilix is only obscure! y suggested by the Texas specimen in its imperfect state of preservation. Dimensions: Length 12.6 mm., height 5 mm., convexity about 1.5 mm. Compared with the holotype this mold is smaller, more slender, and proportion­ately not quite so high in the anterior portion. However, it appears to he es­sentially like some of the specimens in a large suite, from the Narrows of South Platte River, 50 miles east of Greeley, Colorado (U.S.N.M. no. 9973), which White himself identified with his species; this lot includes both internal molds and nearly perfectly preserved shells. Types.-Holotype, U.S.N.M. no. 8913; from the upper part of the Pierre shale, or the Fox Hills sandstone, 4 miles north of Golden, Colorado. One plesiotype? from Texas, U.S.N.M. no. 76288. Distribution in Texas.-Navarro group, Nacatoch sand: Vicinity of Kaufman (761). The Unfrersif y of Te.ras Publication No. 4101 Outside distributio11.-Wl'stern lntf'rior: l'pper part of Pierre shale. or Fox HiJI~ sandstone. of Colorado. Cannonball marine member of Lance formation of the Dakotas. Superfamily ~l'Cl;L\CE. .\ Family ~LCLLID..\E Genus NUCULA Lamarck NUCULA PEREQUALIS Conrad Pl. 8. figs. 7-9 1860. .Yucula perequalis Conrad...\cad. ~at. Sci. Philadelphia ]our.. 2d ser.. ml. -t p. 281. 1860 . .Yucula eufalensis Gabb. :\cad. ~at. Sci. Philadelilhia lour.. 2d ser.. ml. -l. p. 397. pl. 68. fig. 35. 1861. .Yucula perequalis Conrad. GaLb, . .\m. Philos. Soc. Proc .• ml. 8. p. ~0-1. Reprint. p. 149. 1861. 1905. .Yucula eu falensis GaLb. Johnson. ..\cad. Nat. Sci." Philadelphia Proc.. ml. 57. p. 7. Shell of medium size for the genus, thin, suboYate elongate in outline, equi­rnh-e~ slightly inequilateral, moderately conYex. with greatest inflation below the beak. , Beaks ....moderately prominent, in­curYed, approximate, nearly direct. Hinge not well exposed but apparently essen­tially like that of shells from near Eufaula, Alabama. the type locality of the species. In the latter the teeth are numerous I about -W) and in each Yah-e are about equally di,·ided into an anterior and pos­terior series by a deeply :'unken, triangu­lar chondrophore situated directly beneath the beak; the anterior row is slightly arched upward~ a11d the posterior row slightly concaYe upward; the teeth are prominent and are separated by deep sockets: each tooth is an2:ulated in its trend a,cross th~ hinge plate. the angula­tion directed toward the beak in both the anterior and posterior series. The inner margin appears to be smooth. The an­terior and posterior margins are sharply rounded and the basal margin broadly rounded; the anterodorsal margin is hroadly arched, and the posterodorsal margin broadly eonca,·e. these two mar­gins slope away from the beak at an angle of about ]35 degrees. Escutcheon elongated. bounded by a moderately dis­tinct rid!!e. which is bordered without bv a shallo~L . rather broad, radiating sulcu~. The lunule is n~rY faintly outlined and is al~o hord~red h,· ~ simila.r. shallow radiat­ing sulrn~. Su~·face marked by numerous ratlwr fa int. com pact I~-arranged, flattish concentric ridges. Dimensions .. of the largest specimen, ~hO\rn in plate 8. fig. 7: Length 19.5 mm.. height 11. 7 mm., convexity about -1 mm. The Texas material is not as well pre­$erYed as that from near Eufaula, the type locality. but appears to differ in no es­sential respect from typical specimens. Typcs.-Conrad's holotype is not listed among the Cretaceous types in the Acad­emy of l\atural Sciences of Philadelphia, and is probably lost. Gabb's type of I\'ucula eufaulensis, which he later re­garded as synonymous with Conrad's specie~, is present in the collections of the Acad( 1ny and appears to be essentially like the Texas shell except that the latter is larger (about 5 mm. longer). Although the ex '.'.Ct locality near Eufaula, Alabama, at wh i · h the holotype wa~ obtained, is not known, the left Yah-e l857) from Chat­tahooc ~ -ee River, about 2 miles below Eufau:;:~ shown in plate 8, figs. 9, 10, may be reasonably regarded as a neotype IT.S.X.M. no. 76289). One plesiotype from Texas, V.S.N.M. no. 76290. Dist· ~bution in Texas.-1\avarro group, :\eylandYille marl: 21,~ miles north of Corbet {16170, loc. of plesiotype; Texas Bu. 17300). l\a,·arro group, Nacatoch sand: 1 4/5 miles northeast of Quinlan (16162). Outside distribution.-l\Iississippi: Rip· ley formation and Prairie Bluff chalk. Chattahoochee region ( A l a b a m a­Georgia) : Blufftown formation, Ripley formation (upper part)~ and Providence sand. Range.-ln general in the Coastal Plain the range is through the E. ponderosa and E. costata. zones. NUCULA CIBOLOENSIS Stephenson, n.sp. Pl. 8, fig. 10 ~h~l~ large, thick, suboYate-elongate, Leak situated three-fourths the lenoth of t~e sh~ll from the anterior extremit;. The lunge is '":ry imperfectly exposed, but the keth, which number 10 or 11 to the Invertebrate Fossils of the Navarro Group centimeter, appear to be normal for the group of large, elongated, Upper Creta­ceous representatives of Nucula. Inner mar· gin finely crenulated, hut other internal characters concealed by hard matrix. Anterodorsal margin broadly convex; posterodo1sal margin moderately steep; anterior margin sharply rounded midway of the height; ventral margin hroadl y and regularly rounded, finely crenulated, the crenulations corresponding to the external ribs; posterior margin sharply rounded midway of the height. Lunule indistinct, escutcheon moderately well defined. Sur­face marked by rather faint concentric growth lines, with irregular Iy spaced rest­ing stages, and, where uncorroded, hy numerous low, fine, faintly developed, radiating ribs separated by wider, very thallow inters paces; the marginal dentic­ulations correspond to the inters paces; corroeion reveals a strong internal radiat­ing shell structure. The larger shells ex­hibit the sharp inbending of the postero­'fentral margin, which is indicative of a eenile stage in many bivalve mollusks. Dimensions of the holotype: Length 37.5 mm., height 25 mm., convexity 9.3 (?) mm.; the shell has been slightly crushed in the umhonal region. This species belongs to an elongated, thick-shelled group of Nuculas which is typified by the nearly perfectly preserved Nucula percras&a Conrad from the Ripley formation of Mississippi. The latter is typically smaller, more elongated, cor­respondingly sharper both front and hack, uaumes old-age characters at an earlier stage, and possesses a faint posterior radiating sulcus which is lacking in N. ciboloen&is. Nucula stantoni Stephenson another member of the group from the Snow Hill marl member of the Black Creek formation of North Carolina, is a smaller, shorter species with a steeper posterodorsal slope. Nucula slackiana ( Gabb) from the North Atlantic Coastal Plain, which is based on an internal mold, appears to be proportionately higher and more bluntly rounded on the extremities, than the Texas species. With poorly preserved material it is dif­ficult to differentiate the species of this group. Types.-Holotype, U.S.N.M. no. 76291; 6 selected unfigured paratypes, U.S.N.M. no. 76292. Distribution in Texas.-Navarro group, Kemp clay: West of Zuehl (7720; 7721, type loc.); Webberville (7601, 13910); near Deatsville (764, 14125); 2 miles northwest of Deatsville (14128) ; branch 61h miles southwest of Currie (17377); 3~~ miles northwest of Bazette (12922). NUCULA CHATFIELDENSIS Stephenson, n.sp. Pl. 8, figs. 11, 12 This species is similar in all its generic characters, and in most of its specific characters, to Nucula ciboloensis Stephen ­son but differs in its greater convexity and in its apparently steeper posterodorsal slope. The available material is not very well preserved and the best specimens have been subjected to slight mechanical deformation. There is a faint suggestion of a posterior radiating sulcation such as characterizes Nucula percrassa Conrad, which is a more elongated species with sharper terminations. The lower strati­graphic position together with the differ­ences noted, justify separating N. chat­fi.eldensis from the other species of the group. Dimensions of the holotype: Length 38 mm., height 24.4 mm., convexity 11 mm, Types.-Holotype, U.S.N.M. no. 76293; 1 unfigured paratype, U.S.N.M. no. 21057. Distribution in Texas.-Navarro group, Nacatoch sand: Vicinity of Chatfield ( 762, type loc.) ; field south of Chatfield (7569); 3/5 to 4/5 mile northeast of Chatfield ( 14117) ; vicinity of Kaufman (761) ; 1 4/5 miles northeast of Quinlan (16162). Navarro group, Corsicana marl: About 5 miles east by north of Greenville (12924); west of Kaufman (7548); 2 3/5 miles north by east of Malta (16159); 114 miles south by east of Oak Grove (16160). The University of Texas Publication No. 4101 NUCULA MICROSTRIATA Gardner Pl. 8, figs. 13, 14 1916. Nucula microstriata Gardner, Maryland Geol. Survey, Upper Cretaceous (2 vols.), p. 515, pl. 19, fig. 7. This simple little nutshell is smooth with the exception of fine incremental lines and fine, closely spaced radiating lines; it is ovate, moderately elongated, and has a steep posterodorsal slope. The lunule is indistinct, but the escutcheon is sharply defined, extends to the angular posterior extremity, and is moder~tely ex­cavated in each half. The anterior part of the shell is rather high, and a shallow sulcation extends from in front of the beak to the short, truncated anterodorsal margin. . Dimensions of the nearly complete In­dividual shown in the figures: Length 8.5 mm., height 7 mm., thickness 4 mm. A !;pecimen from near Chatfield is slightly more elonaated than the typical form and is questio;ably regarded as an individual variant. This species is similar to Nucula cuneifrons Conrad, from the Ripley for­mation at Eufaula, Alabama, but is a decided! y more elongated form. Type.-Collection of the Maryland Geological Survey, on deposit in the U.S. National Museum. One plesiotype from Texas. U.S.N.M. no. 20887. Distribution in Texas.-Navarro group, N acatoch sand: Vicinity of Corsicana (763, 1 specimen figured); Watkins' place, 3 miles north of Corsicana (9552) ; road 5 miles south-southwest of Corsicana (7573.) Outside distribution.-Maryland: Mon­mouth formation. NUCULA WALTONENSIS Stephenson, n.sp. PI. 8, figs. 15, 16 Shell small, subtrigonal in outline, a little longer than high, moderate! y convex, greatest inflation well above the midheight about at the midlength. Beaks prominent, incurved, opisthogyrate, approximate, sit­uated about 0.7 the length of the shell from the anterior extremity. Hinge and internal features not uncovered. Lunule obscure; escutcheon relative! y wide, deeply excavated, edges rounded. Antero­dorsal margin inclined, broadly arc~ed; anterior extremity sharply rounded a little below the midheight; ventral margin broadly rounded; posterior ~xtr~mity sharply rounded below the m1dhe1ght; posterodorsal margin steep, concave. Sur­face marked by very small, closely spaced, low radiating ribs numbering 9 or 10 to the millimeter, separated by mere lines; growth lines very fine. Dimensions of the holotype, a nearly complete shell with both valves attached: Length 6.8 mm., height 5 mm., thickness 3.8 mm. Compared with Nucula amica Gardner, from the Monmouth formation of Mary· land, this species has very much finer con­centric and radial sculpture, and the radial ribs are stronger than the growth lines. Type.-Holotype, U.S.N.M. no. 76295. Distribution in Texas.-Navarro group, N acatoch sand: 3 miles northeast of Cor­sicana ( 9545, type loc.) ; road 5 miles south-southwest of Corsicana (7573). NUCULA NACATOCHANA Stephenson, n.sp. Pl. 8, figs. 17, 18 Shell small, subelli ptical in outline, much longer than high, moderately con­vex, greatest inflation above the midheight and a little back of the midlength. Beaks moderate! y prominent, incurved, opistho­gyrate, approximate, situated about three­fourths the length of the shell from the anterior extremity. A broad shallow ex­cavation extends from the beak to the posterior margm above the sharply rounded extremity. Hinge and internal features not uncovered. Lunule long, very narrow, distinct!y outlined; es­cutcheon wide, distinct, slightly excavated. Anterodorsal margin long, broadly arched, keeled anteriorly, with parallel excava· tions on either side of the keel; anterior margin sharply rounded, slightly trun· cated above; ventral margin broadly rounded, rising more steeply toward the rear; posterior margin angular at the extremity; posterodorsal margin slightly keeled, slightly arched, steep. Surface marked only by fine, but somewhat irreg· ular growth lines. Invertebrate Fossils of the Navarro Group Dimensions of the nearly complete holo­type: Length 7 mm., height 5 mm., thick­ness 3.25 mm. The species is similar to N ucula microstriata Gardner, but is propor· tionately more elongated. Holotype.-U.S.N.M. no. 21058. Dutribution in Texas.-Navarro group, Neylandville marl: Corsicana road 2~~ miles north of Corbet ( 17365) . Navarro group, Nacatoch sand: Vicin· ity of Chatfield ( 762, type loc.) ; vicinity of Corsicana ( 763) ; 3 miles northeast of Corsicana (9545) ; 4 miles north of Cor­sicana ( 17366) . Range.-Neylandville marl and Naca­toch sand in Texas. Unidentlftecl apedmena of NUCULA One medium sized internal mold of a Nucula, with part of the ~hell attached to the right valve, was found in the Ney­ landville marl in a field 1 3 /5 miles east­ northeast of Black Hills School, 3% miles north-northwest of Corsicana, Navarro County (16166). This specimen is rather short, moderately inflated, with the beak well back of the midlength; the postero­ dorsal slope is steep and the anterior end is sharply rounded; the surface is marked by faint concentric growth lines, and by numerous weak compactly spaced radiat­ ing ribs; the ventral margin is crenulated. The specimen is not suitable to serve as a type. U.S.N.M. no. 76296. An internal mold, probably from the Nacatoch sand is recorded as having come from near Terrell, Kaufman County (U.S.N.M. no. 76385, replacing old no. 12246). An internal mold of a left valve of a rather convex Nucula, 13 mm. long and 7 nun. high, with beak a little back of the midlength, found in the Kemp clay, 4 miles southeast of Zorn, Guadalupe County (10877), is too imperfect for specific identification. U .S.N .M. no. 76297. In the same formation in a field 3 miles southeast of Manor, Travis County (16141), were found two small internal molds of a Nucula, with the external mold of the larger one incompletely preserved. This species is only moderately inflated and is subtriangular in outline with the beak a little back of the midlength; the margin is finely crenulated; the surface, as shown by a squeeze, exhibits numerous, distinct concentric ribs, and fainter, com­pactly arranged radiating ribs. U.S.N.M. no. 76298. Two internal molds of Nucula from a locality in the upper part of the Kemp clay of the Navarro group, about 50 yards from the Lone Oak pike, on the east side of Cowleech Fork of Sabine River, 12 miles southeast of Greenville, Hunt County ( 1124 7), although well preserved as molds, do not agree closely enough in for~ with described species to permit their safe identification. U .S.N .M. no. 76299. Family NUCULANIDAE Genus NUCULANA Link, senau lato The N uculanidae are not as well repre­sented in the collections from the Navarro group as might be expected, for the Ii ving conditions appear to have been favorable for organisms of this kind during the deposition of the formations. Future col­lecting may bring to light a much better representation of this family. Seven named species are described from the Navarro group. Nuculana longifrons (Conrad) is represented by a goodly num· her of individuals, mostly imperfectly pre· served, from several localities; N uculana corsicana by 5 individuals from one local­ ity; and the other 5 species each by only 1 or 2 individuals. Half a dozen species, recognized as distinct, but too imperfect for naming, are given letter designations. NUCULANA CORSICANA Stephenson, n.sp. Pl. 8, figs. 19, 20 Shell rather short, moderate} y convex below the beaks, compressed posteriorly by a broad, radiating sulcation on each valve. Beaks approximate, moderately prominent, nearly direct, situated about 2/5 the length of the shell from the an· terior extremity. Angle of the antero· with the posterodorsal slope 135 degrees. Posterodorsal margin nearly straight. Escutcheon distinct, long and narrow, The University of Texas Publication No. 4101 and nearly equally divided on each valve by a faint ridge. Anterodorsal margin broadly arched. Lunule moderately dis­tinct, narrow. Lunule and escutcheon each divided longitudinally by a low, sharp keel formed by the raised margins of the l\vo valves. Anterior margin sharply rounded; yentral margin broadly rounded, slight!y truncated posterioriy; posterior extremity sharply rounded, almost bluntly pointed. Surface marked by numerous distinct, uniform concentric ridges which fade out on the posterior sulcations where they are replaced by fine growth lines. Dimensions of the holotype: Length 7.2 mm., height 4 mm., thickness 3 mm.; length of largest cotype 11 mm. This ~pecies is not very close to any of the described species of the Coastal Plain. It is similar in form to Nuculana pin­na/orma (Gabb) from the Woodbury clay, Haddonfield, New Jersey, but is not so pointed posterioriy, and is much more finely ornamented. Types.-Holotype, U.S.N.M. no. 76300; 4 unfigured paratypes, U.S.N.M. no. 20884. Distribution in Texas.-Navarro group, Neylandville marl: ?21/2 miles north of Corbet (16170; Texas Bu. 17300). Navarro group, Nacatoch sand: North edge of Corsicana (518) ; vicinity of Cor­~icana (763, type loc.). NUCULANA COLORADOENSIS Stephenson, n.sp. Pl. 8, fig. 21 The description is based on the holo­type only, which is broken about the um bone. Shell small, short, moderateIy convex, slightly compressed posteriorly. Beaks direct, rather prominent, tips deeply incurved, approximate, situated about two-fifths the length of the shell from the anterior extremity. Posterodorsal margin high and nearly straight. Lunule narrow, bounded by a sharp ridge which is paral­leled on the outer side by a faint narrow channel. Escutcheon long, narrow, bounded by a prominent sharp ridge which is paralleled on the outer side by a distinct channel a little wider than the left half of the escutcheon, and extending to the end of the shell. Anterior margm sharply rounded, ventral margin broadly rounded, with a slight truncation pos­teriorly, posterior margin more sharply rounded than the anterior. Internal shell features not uncovered. Surface glossy and smooth except for very fine faint in­cremental lines. Dimensions of the holotype: Length 5.2 mm., height about 3.9 mm., convexity about 1.1 mm. Type.-Holotype, a left valve, U.S.N.M. no. 76301. Distribution in Texas.-Navarro group, Kemp clay: Webberville (7601). NUCULANA TRAVISANA Stephenson, n.sp. Pl. 8, fig. 22 The description is based on two im­perfect right valves. Shell small, short, subelliptical in outline, moderately con­vex, greatest inflation under the beak, slightly compressed posteriorly. A sub­angular umbonal ridge extends from the beak to the posterior extremity, in front of which is a broad shallow depression extending to the margin. The postero­dorsal slope is steep. Beak broken. Hinge and internal characters not uncovered. Anterodorsal margin slight!y arched; an­terior margin rather sharply rounded; ventral margin broadly rounded; posterior extremity subpointed a little above the midheight; posterodorsal margin nearly straight, gently inclined. I'he surface is covered with strong, sharp, asymmetric, concentric ridges, the upper slope of each of which is short and steep, and the lower long and gentle; these number about 5 to the millimeter near the margin, but become smaller and more closely spaced toward the beak. Dimensions of th1e holotype, a right valve: Length about 5 mm., height about 3.25 mm. The form of this species is similar to that of N. coloradoensis, from the same locality, but its strong sculpture is in marked contrast to that smooth species. IV. whitfieldi (Gardner) is similarly sculptured, and is proportionately more elongated and more ventricose. Types.-Holotype, U.S.N.M. no. 76302; 1 unfigured paratype, U.S.N.M. no. 76303. Invertebrate Fossils of the Navarro Group Dutribution in Texas.-Navarro group, Kemp clay: Webberville (13910, holo­type; 7601, paratype). NUCULANA HOUSTONI Stephenson, n.sp. Pl. 8, fig. 23 Shell of medium size, moderately con­vex, compressed posteriorly, with a broad shallow sulcation extending from the beak radially to the posteroventral margin. Beaks approximate, hut not well preserved in the available material, situated about two-fifths the length of the shell from the anterior extremity. Anterodorsal margin rounding down into the rather sharply rounded anterior extremity; ventral mar­gin broadly rounded becoming slightly truncated posteriorly; posterior extremity modified by a short vertical truncation. Lunule narrow and not sharply outlined; escutcheon long narrow, hounded on the outer side by a round-crested ridge which is paralleled on the outside by a distinct narrow channel, the width of which in­creases slightly toward the extremity. Sur­face marked by 20 or more sharply de­fined subconcentric, asymmetric ridges whose upper slopes are short and steep and whose lower slopes are relatively broad and gently inclined. These ridges do not conform strict! y to the growth lines which they cross obliquely toward the pos· terior extremity. The ridges do not ex­tend to the posterodorsal margin, but end at the edge of a narrow, smooth band which parallels on the outside the postero­dorsal channel already described; the band has a maximum width at the ex­tremity of about 0.6 mm. and is crossed by fine straight, vertical growth lines. The internal characters are not uncovered, hut on one internal mold from the same locality, which probably belongs to this species, the teeth are numerous and nor­mal for the genus, the pallial line is near the ventral margin, and the faintly im­pressed pallial sinus is of moderate length, and broadly rounded anteriorly. Dimensions of the holotype, a left valve: Length 8 mm., height 4 mm., con­vexity 1.5 mm. Type.-Holotype, U.S.N.M. no. 21036; 1 paratype, U .S.N .M. no. 76304. Named for the Hon. Sam Houston, President of the Republic of Texas, 1836-1838. Distribution in Texas.--Navarro group, Nacatoch sand: Vicinity of Kaufman (761, type loc.); ?vicinity of Chatfield (762). NUCULANA CORBETENSIS Stephenson, n.sp. PL 8, fig. 24 Shell of medium size, strongly inflated centrally below the beak, more com­pressed posteriorly than anteriorly. The inflation is emphasized by a broad, very shallow, radiating depression which passes from behind the beak down to the postero­ventral margin. Beaks prominent rising high above the dorsal margin, nearly di­rect, strongly incurved, approximate, sit­uated slightly in advance of the midlength. Angle of the antero-and posterodorsal slopes about 120 degrees. Anterodorsal margin broadly arched; an­terior margin rather sharply rounded; ventral margin broadly and evenly rounded; posterior extremity sub pointed; posterodorsal margin nearly straight, gently inclined. Lunule of moderate length and faintly outlined; escutcheon long, broad, rather sharply outlined, each half subdivided by a faint median longi­tudinal ridge. Surface ornamented with numerous rather sharp concentric ribs which vary in width and strength, ap­parentl y reflecting favorable and less favorable conditions of growth. Dimensions of the incomplete holotype, a right valve: Length 7 + mm., height 5.1 mm., convexity about 2.5 mm. The species is represented by the holo­type, a medium sized right valve with the posterior partly broken away, and by two small, incomplete individuals, one with the two valves attached, and the other a left valve. The species resembles N. corsicana, but is proportionately higher, and more inflated, has a more prominent beak, and is more coarsely sculptured. Types.-Holotype, U.S.N.M. no. 76305; 2 paratypes, U.S.N.M. no. 76306. Distribution in Texas.-Navarro group, Neylandville marl: 21;2 miles due north of Corbet (17365; 16170, type lot; Texas Bu. 17300). The University of Texas Publication No. 4101 Navarro group, Nacatoch sand: 4 miles north of Corsicana ( 17366) . Range.-Ranges from the Neylandville marl into the lower part of the Nacatoch sand. NUCULANA LONGIFRONS (Conrad) Pl. 8, fig. 25 1860. Leda longi/rons Conrad, Acad. Nat. Sci. Philadelphia Jour., 2d ser., vol. 4, p. 281, pl. 46, fig. 18. 1864. N uculana longi/rons (Conrad) . Meek, Check list of the invertebrate fossils of North America, Cretaceous and Jurassic, Smithsonian Misc. Coll., vol. 7, no. 177, p. 8. 1885. N uculana longi/rons (Conrad) . Whitfield, U.S. Geol. Survey Mon., vol. 9, p. 107, pl. 11, figs. 16, 17. (Geol. Survey New Jersey, Paleontology, vol. 1, p. 107, pl. 11, figs. 16, 17, 1866.) 1905. Yoldia longi,/rons (Conrad). Johnson, Acad. Nat. Sci. Philadelphia Proc., vol. 57, p. 8. 1907. Yoldia longi/rons (Conrad). Weller, Geol. Survey New Jersey, Paleontology, vol. 4, p. 381, pl. 30, fig. 5. 1916. Y oldia longi,/rons (Conrad) . Gardner, Maryland Geol. Survey, Upper Creta­ceous (2 vols.), p. 518, pl. 19, fig. 13. 1926. Yoldia longi,/rons (Conrad). Wade, U.S. Geol. Survey Prof. Paper 137, p. 41, pl. 8, figs. 13, 14. Shell large, elongated, high for the genus, moderately convex, becoming grad­ually compressed toward the posterior ex­tremity, bluntly rounded on both ends with dorsal and ventral margins sub: parallel. Beaks approximate, small, non­prominent, situated about 0.35 the length of the shell from the anterior extremity. The anterodorsal margin rounds off rather uniformly to the bluntly rounded anterior extremity; the ventral margin is broadly rounded with a faint truncation toward the front, and rounds steeply up both in the front and rear into the rounded ex­tre~ities; posterodorsal margin long, straight, and nearly horizontal at the rear, rounding rather steeply down to the posterior extremity. Lunule very narrow and weakly developed, paralleled on the outside by a shallow, faint, narrow de­pression on each valve. Escutcheon long, narrow and sharply outlined. Surface smooth and polished, but revealing fine, distinct growth lines. Dimensions of the moderate sized in­ternal mold shown in plate 8, fig. 25: Length 18 mm., height 9.5 mm., convexity 2.5 mm. The largest Texas specimen is 30 mm. long. Several authors have referred this species to Y oldia but the species lacks several of the important characters which Dall107 ascribed to that genus. The shell though smooth and compressed, is not pointed behind, has a pallial sinus which is no more deeply impressed than in or· dinary Nuculanas, and the shell is scarcely gaping either at the pedal or si phonal extremity. The species differs from the more typical Nuculanas in its great posterior elongation, its unusual height, and its lack of a pointed extremity. Types.-The holotype was obtained from the Ripley formation at Eufaula, Alabama, and is in the collection of the Academy of Natural Sciences of Philadelphia. One plesiotype, U.S.N.M. no. 76307. Distribution in Texas.-Navarro group, N acatoch sand: Vicinity of Chatfield (762) ; field south of Chatfield (7569) ; % mile east of Chatfield (7570, figured). Navarro group, Corsicana marl: 5 miles southwest of Quinlan (15546); 2 4/5 miles east of Cooledge ( 13832, 14137) ; 1f2 mile below Martindaile ( 15527) ; 2 miles east of Marion (Texas Bu. 2395). Navarro group, Kemp clay: 31h miles north of Bazette (12922) ; Brazos River, 2 miles above Milam County line (13776); south of McQueeney (7638). Outside distribution.-Mississi ppi: Rip• ley and Owl Creek formations in the northern part of the S tate. Tennessee: Ripley formation (Coon Creek tongue) . Chattahoochee region (Georgia • Ala· bama): Blufftown and Ripley formations. Maryland: Matawan formation. New Jersey: Woodbury clay of the Matawan group. Range.-Although in Texas the species has not been found in formations lower than the Navarro group, elsewhere it seems to have a greater range, its lowest reported occurrence being in beds at least as old as the lower part of the Tavlor m~. . 107Dall, Wm. H., Wainer Free Inst. Sci., vol. 3, pt. 3, p. 595, 1895. Invertebrate Fossils of the Navarro Group NUCULANA ap.a Pl. 8, fig. 26 In a collection from the N acatoch sand, in a field near Chatfield ( 7569) , are in­ternal molds of a right and of a left valve of a rather large, ventricose, moderately elongated species of Nuculana too poorly preserved to serve as type m~terial. !he dimensions of the larger specimen, a nght valve, are: Length about 18 mm., height about 9 mm., convexity 3 mm. The posterior margin is rather bluntly and evenly rounded, and the ventral n:iargin is gently rounded below, steepenmg a little toward both the front and rear ex­tremities. U .S.N .M. no. 76308. NUCULANA1 ap.b Pl. 8, fig. 27 There is in one of the collections from the Nacatoch sand, from the public road 3/5 to 4/5 mile northeast of Chatfield, Navarro County (7572), an imperfectly preserved internal mold of one of the Nuculanidae resembling the greatly elon­,,;ated form for which Conrad108 proposed the genus Perrisonota, based on a new species, P. protexta. Gahh109 had in 1860 already described an elongated, though obviously different, species of the same group under the name Leda protexta, so that even if Conrad's new genus, Per­rilonota, be accepted, his species protex~a would seem to he preoccupied by Gahh s species, Leda protexta. A new specific name would, therefore, seem to he needed for the type species of Perrisonota. Nuculana pittensis (Stephenson) from the Snow Hill marl member of the Black Creek formation of North Carolina be­longs to the same group of elongated Nuculanas, as does also Perrisonota little.i Gardner from the Monmouth formation of Maryland. The Texas specimen (U.S.N.M. no. 76309) , a right valve, is not well enough preserved for certain identification, hut it is very much like Conrad's Perrisonota protexta as figured. The anterior part UIConrad, T. A., Amer. Jour. Coach., 1'ol. 5, p. 98, pL 9, &1. 24, 1869. UIGebb, Wm. M•• Acad. Nat. ScL Philadelphia Jour., 2d .... yo). 4, p. 303, pl. 48, fi1. 23, 1860. of the mold is imperfect, hut the shell is flattish and the beak is obviously well toward the front. The posterior part of the shell is greatly elongated and the teeth hack of the beak are small and number 60 or more to the centimeter. The posterior extremity is suhangular and sit­uated near the lower margin, above which the suhtruncated margin slopes strongly forward to the end of the hinge line. The ventral margin is gently and regularly curved, probably bending up .more strongly toward the anterior extremity. Dimensions: Length about 19 mm., height 6 mm., convexity apparently about 1 mm. NUCULANA ap.c Pl. 8, fig. 28 The Corsicana marl has yielded the im­print of a smooth species of Nuculana about 7 .5 mm. long, 4.5 mm. high, and with the beak situated only slightly in ad· vance of the midlength. The specimens are too poorly preserved to serve as ty~es hut the species is probably new. One 1~­ternal mold questionably referred to ~is species is 13.5 mm. long a~d 8 mm. ~igh. Specimens referred to this undescn~ed species are recorded from the followmg localities in the Corsicana marl: Branch below road 2.5 miles north of Tona sid­ing, 5 miles southwest of Quinlan, in !Iunt County ( 15546) ; ?in a pit of Corsicana Brick Company, 2 miles south of Co:­sicana, Navarro County (16167) ; Mexia highway at the forks of the Worth~ road, 2.8 miles east of Cooledge, Limestone County (14137, U.S.N.M. no. 76310); and San Marcos River, half a mile below Martindale, Caldwell County ( 7621) . NUCULANA ap.d Pl. 8, fig. 29 Two small left valves of N uculana from the Kemp clay on Colorado River at Web­berville, Travis County (7601, U.S.N.M. no. 76311; 13910), are similar in form to Nuculana sp. c, but each is only about 7 mm. long. Each consists of an inte~ttal mold with parts of the shell adhermg. The shell is greatly elongated, depressed convex, and smooth. The beak is ~mall and low and ~iluated about 2/ 7 the length of the shell from the anterior extremity. The long dorsal margin is gently arched, the anterior margin sharply rounded, and the ventral margin long and very broadly rounded; the posterior margin is not quite complete. NUCULANA sp.e Pl. 8, fig. 30 An internal mold of a right valve, with some shell material adhering, from the Kemp clay on the John A. Thompson estc1te, 311~ miles northwest of Bazette, Navarro County (12922), is 11 mm. long, 6.5 mm. high, and about 2 mm. in con­vexity. The beak is situated a little in advance of the midlength. The greatest ,·entricosity is below the beak and a little above the midheight, from which point the surface descends in rather steep curves toward the anterior and ventral margins; the posterior part of the shell is noticeably com pressed, becoming slightly excavated on the posterodorsal slope. The ventral margin is broadly and evenly rounded, and the extremities are sharply rounded above the midheight; the dorsal margins are moderate!y inclined, the an­terior one slightly arched, and the pos­terior one nearly straight. U.S.N.M. no. 7(>312. NUCULANA sp.f One poorly preserved individual of a large, greatly elongated species, was found m the Kemp day on Colorado River at Webberville, Travis County (]3910). The specimen is estimated to be about 30 mm. long and 8 mm. high under the beak; the height decreases to­ward thf' rear until at the almost squarely truncated extremity the shell is onl v about 3 mm. high. The valves are com.pressed and fragments of the shell ~how the sur­face to he ~mooth except for very fine growth lines. V.S.N.M. no. 76313. Other unidentified specimens of NUCULANA An internal mold from the Corsicana marl, in the pit of the Corsicana Brick Company, 2 miles south of Corsicana, Navarro County (16167), has about the same outline as the one from near Odds (see below), but is flatter, perhaps due to mechanical compression. The concentric ribs which are impressed on the mold are sharp, numerous and regular. This shell is similar in form, size, and ribbing to N. travisana., but, as preserved, is flatter. U.S.N.M. no. 76314. A small internal mold from the Kemp clay of the Navarro group, in a branch near the oil-12rospecting well of Moss & Keeling, W. D. Moody No. 1, 6Y2 miles southwest of Currie, Navarro County (14139), is too poorly preserved for iden­tification or specific description. U.S.N.M. no. 76315. A small right valve from the Kemp clay in Tom Thrasher's dug well near Gar­field, Travis County (1641), is probably a young individual, and i~ hardly ade­quate to serve as a type. U.S.N.M. no. 76316. A ferruginous, oxidized left valve from the Kemp clay in a road ditch half a mile west of Elm Creek school, 41/2 miles northwe~t of Lockhart, Caldwell County (15528), is 14 mm. long, jg moderately convex, has its beak about midway of the length, narrows nearly to a point pos· teriorly, and has a convex posterodorsal margin. It is too poorly preserved to serve as a type. U.S.N.M. no. 76317. An external mold of a small right valve, from the Kemp clay, 1/2 mile west of Odds, Limestone County (15434), is a short, moderatel y high, moderate! y con­vex species, with numerous sharply de­veloped concentric ridges. It is not complete enough to serve as a type. U.S.N.M. no. 76318. Superfamily P ARALLELODONT ACEA A partial classification of the arcid Pelecypoda, recently proposed by Mac· Neil,110 is here tentatively accepted, pend· ing the decision of the International Com· mission as to the valid genotype of Arca. 110MacNeil, F. Stearns, Washington Acad. Sci. Jour., vol. 27, no. 11, pp. 452·458, 1937. --, --, U. S. Gt·ol. Survey Prof. Paper 189·A, p. 2, 1938. Invertebrate Fossils of the Navarro Group Family GRAMMATODONTIDAE111 Subfamily NEMODONTINAE111 Genus NEMODON Conrad Type spe(= N. cies.-Nemodon conradi eu/a/,ensis Conrad118 ) ; Johnsnot on11 2 Arca (Macrodon) eu/al.ensis Gabb.11" Dall115 considered Nemodon a synonym of Cucullaria Conrad (Eocene) but it dif­ . fers from that genus in its greater elonga­tion, its more nearly parallel dorsal and ventral margins, its long straight anterior and posterior teeth nearly parallel to the hin~e line, and its coarse oblique liga­mental grooves the last one or two of which on the larger species of the genus may be chevron-shaped and extend in front of as well as back of the beak. NEMODON GRANDIS NAVARROANUS Stephenson. n.var. Pl. 9, fig. I Shell thin, elongated, subrhomboidal in outline, moderately convex. Beaks low, broad, incurved, approximate, slightly prosogyrate, situated about 1/3 the length of the shell from the anterior ex­tremity. A broad, shallow radial depres­aion divides the umbone and extends to about the middle of the ventral margin. The umbonal ridge is a prominent, hToadly rounded swell, slightly humped about midway of the length. The antero­and posterodorsal slopes are only moder­ately steep. The hinge line is long, 21 nun. in the holotype, but the teeth are not exposed in the available material. The cardinal area is long and narrow, and the ligamental grooves appear to number only one or two to each valve. The anterior margin is regularly rounded, meeting the hinge line above at an obtuse angle, and rounding down evenly into the neaxly straight ventral margin which 1s slightly mramily and sub!amily names proposed by F. Steams llacNell in unpublished manmcript. UIJohmon, C. W., A.cad. Nat. Set Philadelphia Proc., "1. S7, p. 9, 1905. See also Stewart, Ralph, Acad. Nat. Sci. Philadelphia Special Pub. No. 3, pp. 66-67, 1930. UIConrad, T. A., Amer. Jour. Conch., Yol. 5, p. 97, pl. t, &,. 16, 1869. WC.bb, W. M., Acad. Nat. Sci. Philadelphia Jeur., 2d .-., TOI. 4, p. 398, )860. :u.IDall, W. H., Wapier Free Inst. Sci. Tnns., vol. 3, '"' t, p. 61S, 1898. and broadly concave centrally. The pos­terior margin is bluntly rounded below, passing above into a broadly convex posterodorsal m a r g i n which inclines strongly forward and meets the hinge line at an angle of about 140 degrees. The sur­face is marked by ·somewhat irregularly developed incremental lines and by faint radiating ribs which, over most of the surface, are obscure, but by their inter­section with the growth lines produce a fain ti y punctate surf ace. Dimensions of the holotype, a right valve: Length 30 mm., height 13 mm., con­vexity 4 mm. The few available shells of this species are imperfect and are only about half as large as the typical N enwdon grandis Wade.116 They differ from Wade's species also in having a proportionate! y lesser height, and the umbonal ridge inclines away from the hinge line a little less steeply. The surface of the Texas variety, though faintly sculptured, is still a little more strongly marked · than the type of the species. N emodon stantoni Gardner117 is also a closely related species, but differs in that the shell is proportionately higher, the umbonal ridge inclines away from the hinge line more steeply, and the sculpture is more strongly marked. The shell which W ade118 identified with N. stantoni is not that species, but is more like N. eufaulensis (Gabb). Types.-H o I o t y p e, a right valve, U.S.N.M. no. 20979; 1 unfigured para­type, a . left valve, U.S.N.M. no. 76319. Distribution in Texas.-Navarro group, Nacatoch sand: Vicinity of Kaufman (761, type loc.); ?north of Rock Branch 3 miles northeast of Corsicana ( 9560) . NEMODON BOWIEI Stephenson, n.sp. Pl. 9, figs. 2, 3 Shell elongated, rather strongly in­flated, subrhomboidal in outline. Beaks low and broad, incurved, approximate, slightly prosogyrate, situated 0.38 the 118Wade, Bruce, U. S. Ceol. Survey Prof, Paper 137, p. 43, pl. 9, fig1. I. 2, 1926 • llTCardner, Julia, Maryland Geol. Survey, Upper Creta· ceous (2 vols.), p. 527, pl. 19, fig. 15, 1916. llBWade, Bruce, op. cil., p. 43. The University of Texat~ Publication No. 4101 length of the shell from the anterior ex­tremity. The beak is divided bv a shal­low radial depression which exte~ds down over the shell a little in front of the mid­length, broadening out and almost dis­appearing at the margin. The umbonal ridge is rather prominent, approaching ~ubangularity, and continues evenly prom­inent to the lower posterior margin. An­tero-and posterodorsal slopes moderately steep, the latter broadly excavated and well outlined. The hinge line is 11 mm. long in the holotype, but the teeth are not ex­posed. In one imperfect specimen the teeth are seen to be long and slender, and therefore normal for the genus. The cardinal area is long and narrow and probably bears about 2 chevron-shaped ligamental grooves. The surface of the holotype is ornamented with low, con­centric, rather evenly spaced ridges 0.5 mm. or less in width, separated by narrow, distinct channels, except in a smooth band 2 to 2.5 mm. wide bordering the outer margin; this band doubtless marks the stage of senility. The surface is further ornamented with obscure, fine, somewhat irregularly spaced, radiating ribs which have their strongest development in the interspaces between the concentric ridges, thus giving to most of the surfac; a punctate appearance. Dimensions of the holotype, a right valve: Length 18.4 mm., height 11.5 mm., convexity 4.5 mm. This species is represented by 10 in­ dividuals most of which are broken and imperfect. Compared with N. grandis navarroanus this species is shorter and higher, thicker-shelled, and has a more pronounced and more regular concentric ornamentation. Types.--H o 1o t y p e, a right valve, U.S.N.M. no. 20901; 8 unfigured para­types, U.S.N.M. no. 76320; 1 unfigured paratype, U.S.N.M. no. 76340. Named for Col. James Bowie, who assisted in freeing Texas from Mexican rule in 1835. Distribution in Texas.-Navarro group, N acatoch sand: Vicinity of Corsicana ( 763, holotype and 8 unfigured para­types) ; north edge of Corsicana ( 518, 1 unfigured paratype). NEMODON ADKINSI Stephenson, n.sp. Pl. 9, figs. 4, 5 Shell thin, of medium size, subrhomh· oidal in outline, moderately convex. Beaks moderately prominent, broad, in· curved, a little less than 1 mm. apart in the holotype, situated about 0.35 the length of the shell from the anterior ex­tremity; umbonal ridge broadly and evenly rounded. The hinge as exposed on one of the paratypes is narrow, and on the posterior end bears 3 narrow elon· gated teeth parallel to the hinge line; the teeth are not well preserved on the an· terior end. Cardinal area amphidetic, B.5 mm. long in the holotype, rather wide in front of the beak, narrow back of the beak, and longitudinally striated with fine growth lines; the area on each valve is deepIy concave in front of the beak about parallel to the hinge, but this excavation sha Hows toward the rear and dies out a little back of the beak; the inner margins of the area on the two valves fit together in a straight line, except along a linear distance of about 2 mm. a little back of the beaks where 2 or 3 rather obscure interfitting notches may be seen. It is probable that the ligament is entirely back of the beaks. A side from the hinge fea­tures just described, the internal features of the shell are not exposed. The anterior margin meets the hinge line at an obtuse angle above, and curves down regularly into the very broadly rounded ventral margin; the posterior margin is rather sharply rounded below, becomes broadly arched and inclined forward above, and meets the hinge line at an angle of about 133 degrees. Surface marked with 65 or 70 low, distinct radiating ribs which are a little wider than the interspaces, and which are of irregular development over the shell as follows: On the anterior slope 3 widely spaced ribs stand out more prominently than the others and each of the interspaces between the large ribs is occupied by 2 to 4 ribs of ordinary size; the ribs on the sides are close I y spaced and fairly uniform in strength; the coars· est and most widely spaced ribs are on the umbonal ridge, from which on the postero· Invertebrate Fossils of the Navarro Group dorsal slope the ribs become finer and more closely spaced toward the hinge. Dimensions of the holotype: Length 12.7 mm., height 8.8 mm., thickness 7.7 mm. This elegant species is represented by the holotype, a somewhat imperfect in­dividual with both valves attached, and by two smaller right valves, one of which is moderately well preserved and the other very imperfect, all from the same locality. Types.-Holotype, U .S.N .M. no. 21044; 2 unfigured paratypes, U .S.N .M. no. 76321. Distribution in Texas.-Navarro group, Nacatoch sand: Vicinity of Chatfield (762). NEMODON MARTINDALENSIS Stephenaon, n.ap. Pl. 9, fig. 6 Shell elongated, moderate} y inflated, 1ubrhomhoidal in outline. The beaks are low and broad and each one is divided by a very shallow radial depression which tends to fade out as it extends centrally toward the ventral margin. The umbonal ridge is broadly rounded and not prom­inent, and the antero-and posterodorsal slopes are of only moderate steepness. The hinge line is long, 16 mm. in the holotype. The teeth are not exposed and the cardinal area is conoealed by the broad down-crushed umbo. The anterior margin is vertical above, meeting the hinge line at a right angle, and rounds down regularly below into the nearly straight ventral margin which is subparallel with the hinge line. The ventral margin curves up a little posteriorly to the subangular extremity, above which the nearly straight posterior margin inclines strongly for­ward meeting the hinge line at an angle of about 120 degrees. The imprint of the sculpture shows that the surface is marked by about 43 radial ribs of irregular strength and spacing on different parts of the shell; centrally the ribs are smaller and closer together than they are either toward the front or rear; they are strong· est and most widely spaced, and quite irregular, on the posterodorsal slope and on the umbonal ridge; they are a little less prominent, more closely spaced, and irregular on the anterior slope. Dimensions of the holotype, a left valve: Length 19 mm., height 9 mm., con­vexity 2.5+ mm. The dimensions given are only approximate as the shell material has all been dissolved away and the speci­men is in reality an internal mold, some­what crushed and flattened, on which the sculpture of the outer surface has been impressed by mechanical compression. There may be some question as to the advisability of founding a species on ma­terial in this state of preservation, but the outline, the form, and the ornamentation are fairly well preserved, and the type locality is easily accessible, though not a prominent exposure. The species bears a general resemblance to N emodon eufaulensis Gabb, but differs somewhat in outline and in form, and is much more strongly and coarsely ribbed. Type.-Holotype, U.S.N.M. no. 76322; 4 unfigured paratypes, U.S.N.M. no. 76323. Distribution in Texas.-Navarro group, Corsicana marl: 1;2 mile below Martindale (7621, 15526, type lots; 15527); 1 3/10 miles north of McQueeney (7637, 15524) ; 21h miles west of McQueeney (15523) . NEMODON EUFAULENSIS LINEATUS Stephenson, n.var. Pl. 9, fig. 7 Shell of medium size, thin, elongated, moderately inflated, subrhomboidal in outline. Beaks low, broad, prosogyrate, partly divided by a broad shallow sulcus which extends with increasing width to the middle of the ventral margin. Umbonal ridge rather prominent and subangular, especially near the beak; posterodorsal slope gentle, excavated radially to form a broad shallow sulcus. Hinge and internal features not uncovered. Dorsal margin long and straight; anterior margin in­clined a little backward above, rounding down regularly into the long ventral mar­gin which is broadly concave centrally; posterior extremity subangular below, with the margin above nearly straight and inclined forward, meeting the hinge at an angle of about 110 degrees. The lateral surface of the shell is marked by regularly arranged, low, con­centric ridges numbering about 3 to the The University of Texas Publication No. 4101 millimeter; they are acentric in cross section with the steepest ~lope above; they reach the anterodorsal margin, hut tend lo fade out into mere increm~ntal lines on the posterodorsal slope. The radial ribs are numerous, low, and vary in width on different parts of the surface; on the anterior slope the rihs are of moderate width and form low nodes at the inter­sf'ctions of the concentric ribs; on the side thP-ribs are very numerous, narrow, and closely packed; the ribs become \vidcr on the umbonal ridge and still "·ider and flattish on the posterodorsal slope; the inters paces between the ribs are narrow, being little more than impressed lines. The whole surface has a punctate appearance due to the crossing of the radial and concentric ridges. Dimensions: Length 13.5 mm., height 6 mm., convexity about 2 mm. The Texas shell is smaller and propor­tionately more elongated than Gabb's type of N. eufaulensis from Eufaula, Alabama; the radi.al ribs are flatter and the inter­spaces narrower, the concentric ribs are sharper and more regular, and the umbonal ridge is a little more prominent and more angular. Type.-Holotype, U.S.N.M. no. 76324. Distribution in Texas.-Navarro group, Nn·landville marl: 21h miles north of Co~bet (l 6170, type loc.) ; ?1h mile north of Cooper (14062). Unidentified specimens of NEMODON Specimens of Nenwdon t0o poorly pre­fierved for specific identification have been found in the Navarro group as follows: In the Neylandville marl 2Y~ miles north­east of Royce City (16157, U.S.N.M. no. 76325) : in the ~acatoch sand in the vicin­ity of Kaufman (761, U.S.N.M.. no. 76326) ; on road 2 miles southwest of Kaufman (7546, U.S.N.M. no. 76327), and on State Highway 22, 21;2 miles west of Corsicana (17368, U.S.N.:M. no. 76328) ~ in the Corsicana marl 11;~ miles south hv east of Oak Grove (16160, U.S.N.M: no. 76329), 1/:! mile below Mar­tindale (15527, U.S.N.M. no. 76330), 1 3 ·10 miles north of McQueeney ( 15524, U.S.l\.M. no. 76331), and near Castroville (766.5, U.S.\".M. no. 76332); and in the Kemp clay, 4 miles southeast of Zorn (l 0877, U.S.N.M. no. 76333), and near Deatsville (761, U.S.N.M. no. 76334). Superfnmily GLYC:YMERACEA Family GLYCYMERIDAE Genus GLYCYMERIS Da Costa GLYCYMERIS ROTUNDATA KAUFMANENSIS Stephenson, n.var. Pl. 9, figs. 8-12 Shell thick, subcircular in outline, sub­equilateral, very slightly oblique toward the lower posterior extremity, moderately convex. Beaks prominent, direct, strongly incurved, about 2 mm. apart in the adult, situated near or slightly in advance of the midlength. Hinge plate rugged, arched, truncated above by the lower straight mar­gin of the cardinal area; in the adult there are 7 or 8 centrally located small, short nearly vertical teeth; these are succeeded both anteriorly and posteriorly by 8 or 9 larcre stronO' teeth which become succes­ b ' 0 sivel y more oblique away from the cen· ter, pointing inwardly, until at the ends the teeth are nearly horizontal; several of the larger oblique teeth are curved or even subangular in their trend. Cardinal area amphidetic, moderately broad, bounded below by a straight horizontal base, 22 mm. long in the holotype, broadly arched above where it is bounded by a thin carina; liga­mental grooves chevron-shaped, sharply impressed, numbering 6 or 7 in the holo­type. Adductor scars small, subequal, the posterior one bounded below by a narrow nonprominent, radiating ridge. Pallial line strong, entire, and lying 5 to 6 mm. from the margin. Inner margin strongly crenulated below, the crenulations becom­ing smaller upward and dying out near the ends of the hinge. Surface marked by fine growth lines, and by 45 to 48 low, broad, flattish, radiating costae separated by narrow, shallow inters paces. Dimensions of the holotype, an adult right valve: Length 48.5 mm., height 47 mm., convexity, 18.7 mm. Dimensions of the paratype, a left valve, shown in plate 9, figures 11, 12: Length 38.6 mm., height 36.l mm., convexity 13. 7 mm. This is one of a group of closely re­lated species and varieties of Glycymeris, which are common in certain zones in the Upper Cretaceous deposits of the Atlantic Invertebrate Fossils of the Navarro Group and Gulf Coastal Plain. This form is &earcely distinguishable from G. rotund,ata ( Gabb), from Eufaula, Alabama, hut ap· ~to be slightly less convex with broader, less obscure and more regularly spaced costae, and probably averages a little higher with respect to the length. Glycymeris lacertosa Wade, from Coon Creek, Tennessee, is also a closely related species but, in a large series, is consistent! y less convex and more oblique than the Kaufman species. G. hamula (Morton) from Prairie Bluff, Alabama, is a smaller, 1111oother, and relatively more convex species. G. whiteleyensis Stephenson from Whiteley Creek Landing on Neuse River, North Carolina, is a thinner-shelled, higher species, and has finer and more numerous ligamental grooves. Typea.-Holotype, an adult right valve, U.S.N.M. no. 76335; 1 figured paratype, U.S.N.M. no. 76336; 38 selected unfigured paratypes, U.S.N.M. no. 76337. DUtribution in Texas.-Navarro group, Nacatoch sand: Field 3/5 mile west of Kaufman (14103, type loc.); road, 3/5 mile west of Kaufman (7545, 13923, 14008); vicinity of Chatfield (762). Uahlentilled apeclmena of GLYCYMERIS Two small, imperfectly preserved speci­mens from the Neylandville marl, in a road ditch 2% miles south of Ben Hur, Limestone County ( 15543), are question­ably referred to Glycymeris. U.S.N.M. no. 76339. A small poorly preserved internal mold from the Nacatoch sand, on the northward­facing slope of Sulphur Creek valley, in the northwestern corner of Franklin County (12931), probably belongs to the genus Glycymeru. U.S.N.M. no. 76338. Family NOETIDAE Subfamily TRINACRIINAE Cenua LINTER Stephenaon 1937. Linter Stephenson, Washington Acad. Sci. Jour., vol. 27, no. 11, p. 449. Type species..-Linter acutata Stephenson. Etymology.-Latin linter, a boat or skiff. Linter and Breviarca belong to a group of taxodont shells having vertically llriated ligamental areas, to which Mac­ Neil119 has recently applied the family name Noetidae. This genus is characterized by its long and sharply acute umbonal ridge, its short Arca·like hinge, and its broadly excavated triangular cardinal area situated mainly hack of the beak; at the forward end of the area under the beak is a small, tri­angular; amphidetic, multivincular liga­mental area, faintly striated at right angles to the hinge line; the rest of the area is smooth with only incremental lines show­ing. The hinge is slightly arched and is set with 8 or 10 irregular, short, transverse to slightly oblique teeth, separated by deep. sockets. The genus is represented by 8 specimens from Texas, 7 from the Nacatoch sand, described below under the specific name Linter acutata, and 1 from the stratigraph­ ically lower San Miguel formation Maverick County, described under name Linter burrana Stephenson. of the LINTER ACUTATA Stephenson Pl. I 0, figs. 5-7 1937. Linter acutata Stephenson, Washington Acad. Sci. four., vol. 27, p. 449, text figs. 1-3. Shell small, subtrigonal in outline, strongly convex. Beaks prominent, opis­thogyrate, slightly separated, situated about 3/10 the length of the shell from the anterior extremity. The umbonal ridge is sharply angular, the median surface meeting the posterodorsal slope at an acute angle, the crest of the ridge slightly over­hanging as it a pp roaches the beak. A broad, very shallow radiating depression extends to the posteroventral margin in front of the umbonal ridge. The umbonal ridge stands higher than any other part of the shell, and from it the surface rounds down gently to the anterior and ventral margins. The posterodorsal slope is long, broad, and broadly excavated, the concav­ity being slightly modified by a broad median swell; this surf ace meets the car­dinal area at a broad, obtuse angle. The cardinal area is triangular and broadly excavated, its lower straight edge is about 2.25 mm. long in the holotype, and its posterior edge meets the posterodorsal 119MacNeil, F. Steams, Washineton Acad. Sci. Jour., vol. 27, no. 11, pp. 452-458, 1937. The University of Texas Publication No. 4101 slope at an obtuse angle; the ~nteri~r edge is partly concealed by the mcurvmg of the sharp tip of the bea~. Under the ?e.ak is a small, shallow, triangular, mult1vm­cular ligamental pit, which bears 5 or 6 obscure transverse striations; the rest of the are~ is smooth with the exception of fine incremental lines. The hinge plate is short and narrow; as seen on the holotype it is obscure but appears to be set with .10 or more irregular taxodont teeth which centrally are nearly transverse to the hinge line but toward the ends become more or less oblique; the anterior teeth are chevron-shaped. The inner surface is partly exposed posteriorly in one shell and exhibits radial striae which are strongest near the pallial line. The anterodorsal margin is steeply inclined, but curves down below into the regularly rounded anterior margin, which in turn curves into the broadly convex to nearly straight ven­tral margin; the long, nearly straight, though slightly sinuous, posterodorsal margin meets the ventral margin at a sharp acute angle, forming a pointed extremity; the posterodorsal margin is strongly in­clined forward and meets the hinge line at a very wide obtuse angle. The surface is marked with fine, somewhat irregular incremental lines, crossed by very fine, obscure, radiating ridges which are a little stronger and wider apart on the antero­and posterodorsal slopes; the crossing of the two sets of lines tends to form a faint punctate sculpture; these features are too fine to show clearly in the illustration, and vary in strength on different individuals. Dimensions of the holotype, a right valve: Length 11.3 mm., height 6.8 mm., convexity 3 mm. Types.-Holotype, a right valve, U.S. N.M. no. 75974; 2 paratypes, U.S.N.M. no. 75975; 1 paratype, U.S.N.M. no. 75976; 4 paratypes, U.S.N.M. no. 75977. Distribution in Texas.-Navarro group, Nacatoch sand: 5 miles south-southwest of Corsicana ( 75 73, type loc.) ; 2 miles north of Corsicana ( 9553) ; 4 miles north of Corsicana (17366). Genus BREVIARCA Conrad 1872. Breriarca (:on rad, Acad. Nat. Sci. Phila­delphia Proc., vol. 24, p. 55, pl. 2, figs. 3, -1. (Subgenus of Trigunarca.) 1875. Breriarra Conrad, Geol. Survey North Caro­lina Rt>pt., vol. 1 (by W. c: Kerr), App. A, p. 3. (Subgenus of Trigonarca.) 1876. Breviarca Conrad. l\leek, Rept. U.S.Geol. and Geog. Survey Terr., vol. 9, p. 91. (Subgenus of Trigonarca.) .. 1884. Breviarca Conrad. Tryon, Struct. and ~YS· tern. Conch., Mollusca, vol. 3, p, 257. (Subgenus of Cucullaea.) 1923. Striarca Conrad. Stephenson, North Caro· lina Geol. and Econ. Survey, vol. 5, pt. 1, p. 108. . 1930. Breviarca Conrad. Stewart, Acad. Nat. Sci. Philadelphia Special Pub. No. 3, p. 86. (Designates Trigonarca saffordi (Gabb) Conrad as type species of the genus.) 1935. Breviarca Conrad. Stt'phenson, Wash. Acad. Sci. Jour., vol. 25, no. 8, pp. 362-363, Aug. 15, 1935. Type species.-Breviarca h.addonfieldensis Steph· enson (== Trigonarca ( Breviarca) safiordi Conrad, not Gabb.) In 1923 I placed Breviarca in the synonymy under Striarca, the type species of which is S. centenaria (Say), from the Miocene of Virginia. My reason was that the transverse ligamental grooves pos· sessed by both the Cretaceous and Miocene shells, seemed to be a character f unda­mentall y different from the chevron-shaped grooves of Arca, Barbatia, and other groups of the Arcidae, and indicative of a separate line of descent from a pre· Cretaceous common ancestor. It seemed appropriate, therefore, that the forms possessing the transverse grooves should be grouped together under the older name Striarca. It now seems probable from the work of W oodring,120 MacNeil, and other Tertiary paleontologists, that the group possessing this feature will be subdivided into subgroups, each of which will be given generic rank, in which case it is both appropriate and desirable that the Cretaceous subgroup retain the name Breviarca. Breviarca, although variable in form and outline, is in general less quadrate, less elongate, less strongly ornamented, and has a more strongly arched hinge plate than the typical Striarca centenaria (Say). In his original description of Breviarca, Conrad named two species as examples, the first Trigonarca ( Breviarca} perovalis Conrad, from the Upper Cretaceous at Snow Hill, North Carolina, and the second Trigonarca ( Breviarca) safjordi (Gabb) Conrad, a misidentified species from Cre· taceous deposits at Haddonfield, New Jersey. In 1930 Stewart designated the l:..'OWoodring, W. P., Carncgil! Inst. Washington Pub. no. 366, p. so, 1925. Invertebrate Fossils of the Navarro Group misidentified species from Haddonfield as the type species of the genus. In 1935 I renamed the latter Breviarca haddonfield­ensu. BREVIARCA PLUMMER! Stephenson, n.ap. PL 9, figs. 13, 14; pl. 28 Shell large, thick, rather strongly in­ftated, longer than high. Umbonal ridge prominent, subangular near the beak, be­coming more rounded distally. Antero­dorsal slope moderately steep, rounding oft broadly to the margin except in front of the beak where it is slightly excavated; posterodorsal slope, steep, broadly exca­vated back of the beak, rounding broadly downward to the extremity; in general the shell rounds down broadly from the beak and umbonal ridge to the ventral and anterior margins. Beaks prominent, broad, incurvecl, separated by a space of perhaps I mm., slight! y prosogyrate. Hinge plate broad, arching down strongly at each end, truncated above by the straight, basal edge of the area; teeth numerous, thin, closely spaced, nearly vertical centrally, becoming successively more oblique distally, the end ones being horizontal. Some of the teeth just below the ends of the cardinal area are angulated in their trend, the angulations pointing toward the beak. Cardinal area amphi­detic, rather broad centrally, broad! y arched on the upper margins, straight on the base, which is 13 mm. long on the holotype. The area, except a narrow bor­der above, is closely covered with liga­mental striations which are transverse to the hinge line. Adductor scars unequal, the posterior one the larger. Pallial line simple. Anterior margin regularly rounded, passing below into the very broadly rounded ventral margin; posterior margin subangulated below, nearly straight and inclined forward above, meet­ing the hinge line at an angle of 115 de­gree.. The surf ace exhibits fine, regular inconspicuous growth ridges, with here and there a slight depression, or a slightly stronger ridge, indicating stages of rest and accelerated growth. Very fine radiating striations are present all over the shell; these vary somewhat in strength on different individuals. The crossing of the radial and concentric markings tends to produce a faint punctate appearance. Dimensions of the holotype, a left valve: Length 24 mm., height 20 mm., convexity 8 mm. The species is much larger than Breviarca nolani, is proportionately less inflated, the umbonal region is a little broader, and the umbonal ridge. is a little less angular. Both the concentric and radial markings are a little weaker in this species than in B. nolani, but otherwise the two species are similarly ornamented. B. umbonata Conrad, from the Snow Hill member of the Black Creek formation in North Carolina, is a closely allied species, but is smaller and proportionately more inflated. Types.-Holotype, a left valve, U.S.N.M. no. 76341; 1 figured paratype, U.S.N .M. no. 76342; 8 selected unfigured paTa­types, U .S.N .M. no. 76343; 11 para types in large slab, U.S.N.M. no. 76344 (pl. 28). Named in honor of Prof. Frederick B. Plummer, who collected the piece of fossiliferous sandstone in which the speci­mens included under U.S.N.M. no. 76344 are embedded. Distribution in Texas.-Navarro group, Nacatoch sand: 1 4/5 miles northeast of Quinlan ( 16162, 16171, type loc.) ; 1% miles west of Campbell (12925); vicinity of Kaufman (761, U.S.N.M. no. 21020); vicinity of Kaufman (761, U.S.N.M. no. 20957). BREVIARCA NOLANI Stephenson, n.sp. Pl. 9, figs. 15, 16 Shell small, moderate! y thick for the size, subquadrate in outline, longer than high, strongly convex. Beaks prominent, incurved, slightly prosogyrate, separated by about 0.5 mm., situated about 0.45 the length of the shell from the anterior extremity. Umbonal ridge moderately prominent, subangular near the beak, be­coming rounded distally. Centrally the shell is broadly and evenly convex, and both the antero-and posterodorsal slopes are steep. Hinge plate moderately broad and heavy, arching down more strongly at the anterior than at the posterior end, and truncated above by the straight lower edge of the area. Centrally the hinge i~ set with 9 or 10 small n·rti1·al h't:'th. and these are fallowed on each of th~ down arched ends hY 7 or 8 stronger and lonp:er tC'eth which . become suc-c~ssi,-eh-more oblique. pointing inwardly. until .the end ones are nearly horizontal. The cardinal area is amphidetic and ra~her wide and its lower .straight edge is about 5.5 mm. long on one of the parat~·pes. Fine liga­mental grooves transverse to the hinge line cO\·er a..__small central triangular area haY­ing its apex under the beak and its base, about 1 mm. long on the upper hinge margin: these are faint and scarcely show in the illustration; thev are best seen on one of the paratypes: The rest of the cardinal area is smooth except for fine incremental lines. \\'ith the excep­tion of the hinge the interior of the shell is not uncoYered for obserYation. The anterior manrin is regularh· rounded, meeting the hinge line._at a· moderately obtuse angle, and passing below into the broadh-and r,r~gularh-rounded Yentral • L • margin. The posterior margin is rather sharply rounded below at the extremity, become5 nearly straight aboYe, and meets the hinge line at an angle of 130 degrees. The surface is marked by fairly regular, but not prominent, growth ridges which number -t or 5 to the millimeter toward the outer margin. and by numerous, faint, radiating ribs which tend to giYe the sur­face a fine punctate appearance; although weak the ribs on the holotype show a tendency to alternate in strength; on some shells this tendenn· to differ in size is partieularly ~trong. on the anterodorsal slope, where e\·er~· other or e\·ery third or fourth rib is stronger than the others. There is, howe,·er. considerable individual rnriation in the dewlopment of these ribs. Dimensions of the holotype: Length 6 mm., height 5 nun., convexity 2.5 mm. This species 1s closely related to Breviarca u·ebbervillensis Stephenson but i-s a larger. more robust. and relativelv L . . • higher shell. Compared with B. plummeri it is much smalleL relati,·ely more in­flated. and more pointed posteriorly. The species from the Coon Creek tongue of the Ripley formation in Tennessee, which Wade incorrect I y referred to Barbatia saf­ /ordi (Gabb). is very close to this one, hut i~ ~omewhat more elongated. Trpes.---Holotype. a left valve, from near~ Chat field. LS.\.:\I. no. 76345; 2 un­ figur<:>d paratypes from the same locality, LS.\.M. no. 763--16: 1 unfigured paratype from near Kaufman I LS..\.M. no. 2095i). \amed for Philip .\olan who led an in­ ,·adinrrL' party• into Texas from Louisiana in 1-799. Distribution in Texas.-~avarro group, .\edandYille marl: 21 ~ miles north of Co~·bet l 16170, 17365). .\ayarro group, :\"acatoch sand: ? 2% miles north of Corsicana l l--l-114) ; 3 miles northeast of Corsicana l95-15) ; field south of Chatfield l 7569. loc. of holotype and 2 paratypes) : vicinity of Chatfield (762) ; ,·icinity of Kaufman (761, loc. of 1 para­type) : 1 -1 5 miles northeast of Quinlan l 16162). BREVIARCA WEBBERVILLENSIS Stephenson, n.sp. Pl. 9, fig~. 17-19 Shell small, thin, subquadrate in out­line, considerably longer than high, mod· erately convex. Beaks moderately prom­inent, incurYed, slightly prosogyrate, separated by about 0.5 mm., situated about 0.--l-the length of the shell from the anterior extremity. r mbonal ridge mod­erately prominent, subangular near the beak becoming rounded toward the ex­tremitv. Centralh-the shell is evenly con· wx, becoming st~ep on both the ~tero· and posterodorsal slopes. Hinge plate long, narrow, slight!y truncated by the lower edge of the cardinal area, arching down slightly at the ends, set with about 22 teeth which are small and vertical cen· trally, and become longer and somewhat oblique toward the interior at the ends. Cardinal area amphidetic, about 3.5 mm. long on the base in the holotype, relatively wide, a little wider behind than in front of the beak; the ligamental attachment is confined to a small triangular area under the beak, the sides of which are slightly longer than the base and are slightly con· cave; on this area the ligamental grooves are trans,·erse to the hinrre line· on some . 0 ' of the specnnens this area is still covered with a brown, corneous layer which is also strongly marked with transverse grooves; Invertebrate Fossils of the Navarro Gr.oup the remainder of the cardinal area is smooth except for fine longitudinal growth lines. On the interior the pallial line is simple and fairly close to the margin. The adductor scars are relative! y large and each is bounded on the lower side by a thin radial carina which extends well hack tow~d the beak, and the posterior one of which is the stronger. The left valve slightly overlaps the right on the ventral margin and the edge of the right valve has left a deep groove a fraction of a millimeter within the inner edge of the left valve. The anterior margin is regu· larly rounded, meeting the hinge line above at an obtuse angle, and passing into the broadly rounded ventral margin below. The posterior marg~ is sharply round~d · below becomes straight "llnd strongly m­clined.' forward above, and meets the liinge line at an angle of 134 degrees. The surface is marked by sharply de­fined, low' concentric ridges, 7 or 8 to ~e millimeter, and by numerous fine, f amt, radiating ribs which show a tendency to alternation in size, although there is irregu­larity in this respect, 2, 3, or more smaller ribs intervening in places between the larger ones; the ribs toward the upper antero· and posterodorsal slopes are finer than elsewhere on the surface; the ribbing on the left valve appears to he a little more distinct than on the right. . Dimensions of the holotype, a left valve: Length 5.5 mm., height 4 mm., convexity 1.9 mm. Thie species is represented by 14 in­dividuals none of which is larger than the holotype. Although some of the shells are broken, others, including the holotype, are almost as perfectly preserved as Recent shells. Compared with Breviarca nolani this species is consistently smaller, is pro­portionately more elongated, has a smaller area of attachment for the ligament, and the concentric ribbing is finer. Type1.-Holotype, a left valve, U.S.N. M. no. 76347; 10 unfigured paratypes, U.S.N.M. no. 76348. Dutribution in Texas.-Navarro group, Kemp clay: Webberville (7601, type lot 13910); well 2 miles west of Groesbeck (depth 800 feet) (13124); ?on Brazos River, 2 miles above Milam County line · ( 13776) ; branch 6% miles southwest of Cunie ( 17377). BREVIARCA ap. Several ferruginous internal molds of a large species of Breviarca were found in the Kemp clay 4.5 miles northwest ')f Lockhart (15528, U.S.N.M. no. 76349; 16151, U.S.N.M. no. 76350). They ap­pear to represent an undescrihed species which occurs abundantly in certain layers of the Escondido formation, from Medina County westward to the Rio Grande (pl. 9, figs. 20, 21) ; this formation is regarded as approximately contemporaneous with the Kemp clay. The internal mold of a young individual, probably of the same species, was found 3.2 miles north-north­west of Fentress (16149, U.S.N.M. no. 76351). Family CUCULLAEIDAE Genus IDONEARCA Conrad Type species.-Cucullaea capax Conrad. Conrad's genus is based on perfectly preserved shells from the Ow~ Creek f ?rma­tion on Owl Creek near Ripley, Tippah County, Mississippi, which he originally described under the name Cucullaea capax.121 C. tippana Conrad from the same locality is merely a young stage of C. capax. Several authors have subse­quently put this species in the synonomy of Idonearca vulgaris (Morton) .122 Pilsbry128 has recently called attention to the name Cyphoxis Rafinesque,124 the description of which he concludes "applies in every respect to the casts of Cucullaea of the subgenus ldonearca Conrad, found abundantly in the Cretaceous marls of New Jersey." Rafinesque named four species which, however, were never defined, leav­ing the genus without species. Invoking Opinion No. 46 of the International . Com­mission that a genus proposed without species contains all the species of the wor Id that would come under the original de­scription, and that the first species pub­lished in connection with the genus 121Conrad, T. A., Acad. Nat. Sci. Philadelphia Proc., vol. 24, p. 54, 1872. 122Morton, S. C., Amer. Joor. Sci., lat ser., vol. 17, p. 285, and vol. 18, pl. 3, fig. 21, 1830. uapnsbry, H. A., The NaU:tilus, vol. 42, no. 4, pp. 113-114, i929. See also Stewart, Ralph, Acad. Nat. Sci. l'hiladelphia Spec:al Pub. No. 3, p. 75, 1930. Wft.-.finesque, C. S., Prodrome de 70 nouveaux Genres, Etats-Unis d'Ameriqoe: Joor. de Phys., de Chimie, d'Hi1t. Nat., vol. 88, June, 1819. The University of Texas Publication No. 4101 becomes the type, Pilsbry designated Cucullaea vulgaris Morton as the type of Cyphoxis. The cotypes of Cucullaea vulgaris are 16 internal molds preserved in the col­lection of the Academy of Natural Sciences of Philadelphia. The original drawing is so poor that the figured specimen can not be identified among the cotypes. Since the external features are necessary in the identification of the species of this group the name C. vulgaris at the best can be reasonably applied only to the 16 types, which means the virtual abandonment of the name. It does not seem possible to demonstrate the specific identity of Cucull(Hls. lknrv. Palt•ontographical Soc.. \ol. 2. pt. 9, pp. 388-391, pl. 58. fi :;~. JO-D: pl. 59. fiJ?~. 1-15, 1913. u;\"il~~on, S.. r.·triticata S11rc;111a. FormJtionis Crl'lac<>a, pars prior. Ycrtcbrata C'I \lollusca, pp. 30. 31, tJb. 6. fig. S:\, H. 18:.?7. H"'lfrnnij?. :\... Rn. Lam.·11 br. i :'\ils~on's "Pctrif. Sut•cana Form. Cr.-t.", p. 11, pl. 1. fig!'. } .'l. 17, ;.'!l-23, 2.'>-:.?8. ]8Qi, fiO'nred by Woods those represented by fi;ures 12° to 16. Plate 59, from the zone of Belnnnitella mucronata (upper Senon­ian) aO'ree most closely with the American t" . species. Figure J!t. represents the type of 0. triangularis Woodward,1 ·rn which Woods regards ·as a synonym of 0. incurva. Tvpe.-Collection of the Academy of Natt1ral Sciences of Philadelphia, from the "Blue marl of Arneytown, New Jersey." This is probably the Navesink marl. Two plesiotypes from Texas, U.S.N.M. no. 76393. Dz'.stribution in Texas.-Austin chalk: Public road, 2 mile:-west of Sherman, Grayson County (7516); Prairie Creek, 1~·~ miles southeast of Arnold, Dallas County (7540) ; gullies a mile south of Arnold, Dallas County (7542). Chalk in salt domes: Brooks salt dome, Smith County, at location No. 37 at north end of the saline prairie (11092), at loca· ti on No. 38 ( 11093), in road near the southeast edge of the dome (12947), and in an old quarry on the north edge of the dome west of Copperas Creek (12948). Palestine salt dome, Anderson County, in road, 1/ 5 mile northeast of the salt works (12944). Bonham clay: Randolph road, 6 miles southwest of Bonham, Fannin County (10557) ; Direct road, 1 1/5 miles west of Globe, Lamar County (13074). Blossom sand: 21,,~ miles east by south of Paris (9703) ; 1 1/8 miles south-south­west of the public square, Paris (7508). Brownstown marl: Atlas road, 4 miles south of Paris, Lamar County ( 4056) ; at roadside 4 miles south of Paris (4059). Gober tongue of Austin chalk: Public road~ 4 miles west of Bailey, Fannin County ( 7527) ; Arledge Ridge Church, 5 miles south of Bonham, Fannin County (7729); old rock quarry, 31h miles south of Honey Grove, Fannin County (7534) ; 1 mile west of High, Lamar County ( 4060). Taylor marl: North Sulphur Creek, % mile south of Gober, Fannin County (9566) ; Colorado River, 1 mile east of Dl'h-alle, Trads County (7606) ; Colorado RiYer, 1 mile north-northeast of Delvalle ( 12892) : questionably at Hornsby Bend, Colorado River, 7 miles east of Austin, H!.lWoodward, Samu<'l. An outline of the geology of ~orfolk, :'.\orwich, p. 18, pl. 6, figs. 6, 7, 1833. Invertebrate Fossils of the Navarro Group Travis County ( 7600) ; a small arroyo, 2% miles south of the courthouse at San Marcos, Hays County (7617) ; San Marcos River, below the mouth of Blanco River, Hays County (7618); San Marcos River, 2%, miles southeast of San Marcos, Hays County (7619) ; gully south of Clear Springs road, 4 miles southeast of New Braunfels, in Guadalupe County (7626, 7627) ; Palestine salt dome, at the salt worb at northeast end of the lake, Ander­ son County (I0045) . Pecan Gap chalk: 2 miles north by east of Enloe, Delta County ( 4061) ; rail­road cut 1h mile east of Pecan Gap, Delta County ( 9714) ; near Cotton Belt R.R., 3 miles east by south of Wolfe City, Hunt 'County (9712); 5 miles south of Wolfe City, Hunt County ( 9565) ; branch of Bear Creek, 4/5 mile east of Lavon, Collin County (14090, 2 specimens figured) ; branch at crossing of Otto road, 2 7 /I0 miles southeast of Mart, McLennan County (12913); 200 yards south of Branson Brick Company's plant, 9/10 mile south by west of Marlin, Falls County (12915); Marlin-Cedar Springs road, 5 miles east of Lott, Falls County ( 12917) . Wolfe City sand: Cuts of Santa Fe R.R., I to 2 miles east by north of Wolfe City, Hunt County (9562, 9709, 9710). Annona chalk: Branch 21/i miles north­ west of Annona, Red River County (14077); branch 3 miles southwest of Clarksville, Red River County (14058); Youngs Creek, 4 miles east of Clarksville (13085, 13086). San Miguel formation: Questionably from Uvalde road, 14 miles northeast of Eagle Pass, Maverick County (8251); northward-£ acing slope of Agua de Fuera Creek, 5 miles southeast of Spofford, Kin­ney County ( 8262) . Navarro group, Neylandville marl: 1h mile north of Cooper ( 14062) ; 2 7/I0 miles northwest of Cooledge (16169). Navarro group, Nacatoch sand: Vicinity of Kaufman (761). Navarro group, Escondido formation (Upper part): 15 miles southeast of Eagle Pass, Maverick County ( 10854) ; Cuevas Creek, 3% miles east of Indio ranch head­quarters ( 8236) ; Cuevas Creek, 17%, miles southeast of Eagle Pass (8241, 8242) ; bluff on Rio Grande, 4 miles west of Windmill ranch, Maverick County ( 8239) • Outside distribution.-Arkansas: Tokio formation, Brownstown marl, Ozan forma­ tion (common), Annona chalk, Marlbtook marl, and Nacatoch sand. Tennessee: Selma chalk and Ripley formation (Coon Creek tongue) . Mississippi: Tombigbee sand member of Eutaw formation, Selma chalk, Ripley formation, Owl Creek formation, and Prairie Bluff chalk. Central and west-central Alabama: Tombigbee sand member of Eutaw forma­ tion, Selma chalk, and Prairie Bluff chalk. East-central Alabama and Chattahoochee region (Alabama-Georgia) : Bluff town formation and Ripley formation. Carolinas: Snow Hill marl member of Black Creek formation, and Peedee forma­ tion. Maryland: Monmouth formation. New Jersey: Marshalltown formation, Wenonah sand, and Red Bank sand. Western Interior: Oysters which appear to be correctly referred to this species have been found at several localitis in Colorado, Wyoming, and Utah, in beds which are stated by T. W. Stanton and J. B. Reeside, Jr., to he of middle Pierre age. Stanton150 in 1897 reported the species from an Upper Cretaceous horizon near Harpers, Wyoming, which is of Pierre age. Range.-In Texas the species ranges from the upper part of the Austin chalk upward into the N acatoch sand and Escondido formations of the Navarro group. Geographically the species ranges throughout the Atlantic and Gulf Coastal Plain in beds corresponding in age to those in Texas. OSTREA F ALCATA Morton Pl. 14, figs.. 7, 8 1827. Ostrea fakata Morton, Acad. Nat. Sci. Philadelphia Jour., vol. 6, 1st ser., p. 50, pl. 1, fig. 2. 1830. Ostrea f alcata Morton, Am. Jour. Sci., 1st ser., vol. 17, p. 284, vol. 18, pl. 3, figs. 19, 20. 1834. Ostrea falcata Morton, Synopsis of the organic remains of the Cretaceous Group of the United States, p. 50, pl. 3, fie. 5 (not pl. 9, figs. 6, 7). USOStanton. T. W., Stratigraphy and paleontology of the Laramie and rf'lated format :on1 in W~·oming: Bull. Geol. Soc. Amer., vol. 8, pp. 138, 139, 1897. The University of Texas Publication No. 4101 1860. Ostrea falrata Morton. Owen, Geol. Survey Arkansas 2d Rept. Geol. Reron. Arkan­sas. pl. 7. fig. 5. 1868. Ostrea larra Lamarck. Cook. Geol. Survey New Jersey (Geology of New Jersey), p. 375. text figure. 1869. Ostrea ungulata Coquand, Mon. Genre Ostrea Terrain Cretan~, p. 58, pl. 31, fig. 12. 1870. Ostrea larra Lamarck. Credner, Zeitsch. Deutsch. Geol. Ges .. Band 22, p. 226. 1876. Ostrea !arm Lamarck. Gahh. Acad. Nat. Sri. Philadelphia Proc.. vol. 28. p. 320. 1884. Ostrea ( Alectrvonia) farm Lamarck. White (in part). U.S. Geol. Survey 4th Ann. Rept., p. 296. fig. 8. 1885. Ostrea larra Lamarck. Whitfield (in part), U.S.Geol. Survey l\fon., vol. 9, p. 34, pl. 3, figs. 5-7. (Geo l. Survey New Jersey, Paleontology, vol. 1, p. 34, pl. 3, figs. 5-7, 1886.) ?1889. Ostrea farm Lamarck. Hill, Geol. Survey Texas, Bull. No. 4. p. 6. 1889. Ostrea !arm Lamarck. Hill and Vaughan, ll.S.Geol. Survey 18th Ann. Rept., pl. 44, fig. 2c (not figs. 2a, 2b) . 1899. Ostrea !arm Lamarck. Harris, Geology of Louisiana for 1899, p. 293, pl. 49, fig. 3. 1905. Ostrea falcata Morton. Johnson, Arad. Nat. Sci. Philadelphia Proc., vol. 57. p. 11. 1907. Ostrea falcata Morton. Weller, Geol. Sur· vey New Jersey, Paleontology, vol. 4, p. 444, pl. 43, figs. 3--0. 1911. Ostrea falcata Morton. Miller, l\laryland Geol. Survey, Prince Georges County, p. 96, pl. 5, fig. 6. (Figure only.) 1916. Ostrea !arm suhsp. falrata l\lorton. Gard­ner, Maryland Geol. Survey, Upper Cre­taceous (2 vols.), p. 552, pl. 22, fig. 4. 1923. Ostrea falcata Morton. Stephenson, North Carolina Geol. and Econ. Survey, vol. 5, pt. l, p. 154, pl. 39, figs. 1-10. 1926. Ostrea falcata Morton. Stephenson, Geol. Survey Alabama Special Rept. No. 14, p. 250. pl. 92, fig. 4. (Figure only.) 1926. Ostrea falcata Morton. Wade, U.S. Geol. Survey Prof. Paper '137, p. 55, pl. 14, figs. 9-13. 1929. Ostrea falrata Morton. Dane, Arkansas Geol. Survey ~ull. 1, pl. 25 (op. p. 138), figs. 3, 4. (Figures only.) This species is represented in the Na­varro group by a few imperfectly pre­served specimens from four localities, two examples of ,..,·hich are shown in plate 14, figures 7, 8. Shell long. relatively narrow, and strongly curved backward and upward. Left valve slightly ventricose, right valve compressed or only slightly ventricose. Beaks small. situated midwav of the hinge, slightly prominent on left valve, compressed on right valve. Scar of at­tachment on left valve generally small. The antero-and posterodorsal portions of the shell are provided with wing-like ex­tensions which vary greatly in prominence on different individuals. Hinge small and variable in shape, but in general triangular and crossed by fine growth lines. Liga· mental pit narrow and distinctly im­pressed on left valve, and shallow and more obscure on right valve. Adductor scar of moderate size and situated 5 to 10 mm. below the hinge, near the posterior margin. Surface marked by fine con­centric growth lines and by 5 to 10 or more round-crested, rugose, radiating costae which flare out into prominent plica· tions along the ventral margin of the shell; the costae and intervening depres­sions alternate in position on the two valves which, when closed, fit together in . . a zigzag margin. Dimensions of the shell shown in pl. 14, fig. 7: Length 39 + mm., height 33 mm., convexity 5 mm. Although the shells do not as a rule exceed 40 or 45 mm. in length, specimens from the Selma chalk in the eastern Gulf region are known to attain a length as great as 54 mm. and a height of 45 mm. This species belongs to a group of variable, plicated oysters, one of which, a European form, Lamarck designated Ostrea larva. Many authors have referred all the representatives of the group to Ostrea larva, but, as certain authors have shown, it is possible to subdivide them into several fairly well defined species. In 1829 Morton151 named one of these Ostrea falcata. In 1834 he described152 two varie­ties for which he proposed the names Ostrea falcata var. nasuta (his fig. 6) and Os tr ea falcata var. mesenterica (his fig. 7). In 1907 Weller153 raised the two varie­ties to the rank of species. Lamrack's original description of Ostrea larva is not accompanied by a figure, but he refers to a figure published by Knorrm l:'>I.'.\forton. S. G.. Acad. Nat. Sci. Philadelphia Jour., ml. 6, pt. 1, p. 50, pl. l, fig. 2, 1829. l!'"•:!\forton, S. G., Synopsis of the organic remains of the Cr<'tac<'ous group of the United States, p. SO, pl. 9, 6p. 6, 7. 183-i. ir.aw<'ller, Stuart, Geol. Survey New Jersey, Paleontolol)', ml. 4. pp. 44-1-448, pl. 43, figs. 3-14, 1907. 1',..Knorr, G<'org Wolfgan~. Sammlung von Merckw. der l\atur and Alterthiimern des Erdhod. welche petri(. Korper entl:iilt. Atla!.'. th. 2. pl. II (DYii), fig. 6, Niimberg, 1768. Invertebrate Fossils of the Navarro Group which corresponds more closely to Mor­ton's variety Ostrea /a/,cata var. mesenter­'ica, than to other American representatives of the group. Morton's original figure of Ostrea falcata differs marked! y from Knorr's figure and is, in my opinion, a distinct species. Type.-Collection of the Academy of Natural Sciences of Philadelphia (Mor­ton's coll. no. 244). From the Chesa­peake and Delaware Canal near St. Georges(?). The nearly complete speci­men, with both valves attached, labeled "type" corresponds approximately with Morton's original figure, which is a draw­ing. There is a discrepancy, however, in the label, which indicates new Jersey in­stead of St. Georges, Dela ware, as the source of the specimen. The specimen later figured in Morton's Synopsis appears to be a different one. One plesiotype from Texas, U.S.N.M. no. 76394; 1 plesiotype from Texas, U.S.N.M. no. 76395. Distribution in Texas.-Taylor marl: Questionably in Taylor marl (upper) in Burlington road 2 3/10 miles west-south­west of Rosebud, Falls County ( 14135) ; bluff on Colorado River, 1 mile north­northeast of Delvalle, Travis County ( 12892) ; a small arroyo, 21/! miles south of San Marcos, Hays County ( 7617) ; San Marcos River, below mouth of Blanco River, Hays County (7618). Questionably in the Annona chalk: Creek near the railroad 4 miles east of Clarksville, Red River County ( 543 7) . Questionably from Anacacho limestone, about I ~,4 miles west of Fratt station, Bexar County (7652). Upson clay: Bluff and gullies in west­ward-facing slope of Sauz Creek, 1~~ miles north of the old Burr ranch house, 3 miles northwest of Paloma, Maverick County ( 8256) ; Agua de Fuera Creek, % to % mile below the Galveston, Harris­burg and San .Antonio Railroad bridge near Spofford, Kinney County (8259). Navarro group, Neylandville marl: 71/i miles northeast of Cooper (14084, 2 specimens figured) ; % mile north of Cooper (7509, 1 specimen figured). Navarro group, Nacatoch sand: Vicin­ity of Kaufman ( 761) . Navarro group, Kemp clay: West of Zuehl (7085). Outside distribution.-Arkansas: Ozan formation, Annona chalk, Marlbrook marl, and N acatoch sand. Louisiana: Questionably in the Sara­toga chalk at Rayburn salt dome. Tennessee: Coon Creek tongue of Rip­ley formation. Mississippi: Selma chalk, Coffee sand, Ripley formation, OwI Creek formation, and Prairie Bluff chalk. Central and west-central Alabama: Selma chalk (Exogyra cancellata zone) and Prairie Bluff chalk. East-central A I a b a m a and Chatta­hoochee region (Alabama-Georgia) : Rip­ley formation. The Carolinas: Peedee formation. Mary land: Monmouth formation. Delaware: Crosswicks clay, Marshall-town formation, and Mount Laurel sand. New Jersey: Marshalltown formation and Na-vesink marl. Range.-The range of the species in Texas is through the Taylor marl and beds of Taylor age, and through the Na­varro group. Geographically the species ranges throughout the Atlantic and Gulf Coastal Plain, where it may be found in marine beds at almost any stratigraphic position within the zones of Exogyra pon­derosa and E. costata. OSTREA MESENTERtCA Morton? Pl. 16, figs. 7-9 1834. Ostrea falcata Morton, var.B (the name mesenterica suggested), Synopsis of the organic remains of the Cretaceous group of the United States, p. 51, pl. 9, fig. 7. 1869. Ostrea ungulata Schlotheim. Coquand, Monog. Genre Ostrea Terrain Cretace, p. 58, pl. 31, fig. 10 (only). 1884. Ostrea ( Alectryonia) larva Lamarck. White, U.S.Geol. Survey 4th Ann. Rept., p. 296, pl. 42, figs. 6, 7 (not figs. 2-5, 8, 9). 1907. Ostrea mesenterica Morton. Weller, Geol. Survey New Jersey, Paleontology, vol. 4, p. 446, pl. 43, figs. 9-14. In the general form, size, width, and curvature of the shell, and also in the magnitude of its individual variations, this species is like 0. falcata Morton, and The University of Texas Publication No. 4101 it therefore seems unnecessary to give a de­tailed description of these similar char· acters. Morton treated the species as variety B of 0. falcata, with the suggestion that if found to be a separate species it be called 0. niesenterica. The two species differ markedly, however, in surface or­namentation. In 0. mesenterica the sur­face along a central, longitudinal band is smooth, broadly arched, and is completely wanting in radiating costae, but the mar· gins are strongly plicated or folded, as in 0. falcata, and as in that species these folds vary greatly in number and coarseness on different individuals. The left valves are moderately convex and the right valves vary from slightly concave to slightly con­vex. In a suite of specimens from the Kemp clay, near McQueeney, Guadalupe County, which includes 10 left and 19 right valves, the shells are smooth with the exception of several of the larger specimens, which show incipient marginal plications, and the two largest left valves exhibit several large, coarse plications. Were it not for these two specimens one would feel justi­fied in treating this lot as belonging to a separate species. Type.-The whereabouts of Morton's original figured specimen is not known. Morton says: "My specimens were chiefly obtained in the arenaceous marls near Shrewsbury, New Jersey." Shrewsbury is located on the Tinton sand member of the Red Bank sand, in Monmouth County. One plesiotype from Texas, U .S.N .M. no. 76396; 1 plesiotype from Texas, U.S.N.M. no. 76397. Distribution in T exas.--Austin chalk? : ?bed of Elm Creek, at west end of Ana­ cacho Mountain, 1h mile southeast of the Galveston, Harrisburg &San Antonio Rail­ road bridge, Kinney County ( 8270) . Taylor marl (lower part): ?Walnut Creek, 11;2 miles below the Sprinkle road crossing, Travis County ( 7583) . Navarro group, Nacatoch sand: Vicin­ ity of Kaufman (761). Navarro group, Corsicana marl: Onion Creek, 2~·'2 miles west of old Garfield (7605, 1 specimen figured); ?l 3/10 miles south-southeast of Marion (13389); 2 miles east of Marion (Tex. Bu. 2395). Navarro group, Kemp clay: Near Mc­Queeney (7631, I specimen figured) ; IO miles northeast of Corsicana (9556) • Outside distribution.-Arkansas: Que1­tionahl y in the Brownstown marl and questionaby in the N acatoch sand. Mississippi: Upper part of Selma chalk (Exogyra costata zone) and Prairie Blufi chalk. Central and west-central Alabama: Selma chalk (Exogyra cancellata zone) and Prairie Bluff chalk. New Jersey: Navesink marl and Red Bank sand. Range.-In Texas the species ranges questionably from the upper part of the Austin chalk upward through the Taylor marl and the Navarro group. Although in the Coastal Plain outside of Texas the known occurrences of the species are mainly in the Exogyra costata zone, it will probably he found also ranging through the E. ponderosa zone. OSTREA ap. A small, smooth, very irregular oyster, found in the Kemp clay at Black Bluff on Brazos River, Falls County (13776), is specifically indeterminate. U.S.N.M. no. 76398. Genus GRYPHAEA Lamarck, aenau lato The name Gryphaea is here used in its broad sense to include all the gryphaeoid oysters of both Jurassic and Cretaceous age. According to Arkell155 and other authors, the species of ostreid shells which have been called Cry phaea do not form a monophyletic group and should therefore he reclassified into lesser groups according to their origin, each of which should be treated as of full generic rank within the family. If this he done the gryphaeoid shells of the Navarro group of Texas would seem to fit into the genus Pycnodonte Fischer de Waldheim, 156 the genotype of which is Pycnodonte radiata Fischer de Waldheim (reported to be a synonym of Ostrea vesicularis Lamarck), from the Crimean region, south Russia. It is not lMArkell, W. J., Cotteswold Naturalists Field Club Proc., vol. 25, pt. I, pp. 21·68, 1933. lMFischer de Waldheim, ·Bull. Soc. Imper. Natur. Moacou, Tome 8, pp. 118-120, Tab. 1, 1835. Invertebrate Fossils of the Navarro Group clear from the original figures that Pycno­dome ratliata is in fact a synonym of Ostrea w&iculari& Lamarck, but the two species appear to be at least congeneric. Some authors have treated Pycnodonte as a sub­genus of Gryphaea. CRYPHAEA MUTABILIS Morton Pl. 17, figs. 1-6 1828. Gryphaea mutabilis Morton, Acad. Nat. Sci. Philadelphia Jour., 1st ser., vol. 6, p. 81, pl. 4, fig. 3. I~. Gryphaea mutabilis Morton, Am. Jour. Sci., 1st ser., vol. 17, p. 283. 1834. Gryphaea mutabilis Morton, Synopsis of the organic remains of the Cretaceous group of the United States, p. 53, pl. 4, fig. 3. 1868. Pycnodonta vesicularis (Lamarck). Cook, Geol. Survey New Jersey (Geology of New Jersey) , p. 37 4, the larger text figure. 1885. Gryphaea vesic1Jaris Lamarck. Whitfield, U.S. Geol. Survey Mon., vol. 9, p. 36, pl. 3, fig. 16 (not fig. 15) ; pl. 4, fig. 3 (not figs. I, 2) ; pl. 4, figs. 1-3. 1885. Gryphaea vesicularis var. mutabilis Morton. Whitfield, U.S.Geol. Survey Mon., vol. 9, p. 38, pl. 3, fig. 16. 1900. Gryphaea vesicularis Lamarck. Harris, Geology of Louisiana for 1899, p. 292, pl. 49, fig. 2; pl. 50, figs. I, 2. 1902. Gryphaea vesicularis Lamarck. Taff, U.S. · Geol. Survey 22d Ann. Rept., pt. 3, pl. 51, figs. I, la; pl. 52, figs. 1, la. (Figures only.) 1905. Gryphaea mutabilis Morton. Johnson, Acad. Nat. Sci. Philadelphia Proc., vol. 57, p. II. 1906. Gryphaea vesicularis Lamarck. Veatch, U. S.Geol. Survey Prof. Paper 46, pl. 10, figs. 2, 2a (not figs. 1, la). (Figures only.) 1906. Gryphaea vesicularis Lamarck. Bose, Bol. Inst. Geol. de Mexico No. 24, p. 49, pl. 4, fig. 1 (questionably figs. 2, 3) ; pl. 7, fig. 2; pl. 9, fig. 4; pl. 11, fig. 6. 1907. Gryphaea mutabilis Morton. Weller, Geol. Survey New Jersey, Paleontology, vol. 4, p. 452, pl. 46, fig. I. 1916. Gryphaea (Pycnodonte) vesicularis La­marck (Races A, B, D, E). Gardner, Maryland Geol. Survey, Upper Creta­ceous (2 vols.), p. 572, pl. 28, figs. 1, 2; pL 29, figs. 1-3; pl. 30, figs. 1, 2; pl. 31, figs. 1-3; pl. 32, figs. 1--3; pl. 33, figs. 1-3. 1923.. Gryphaea vesicularis Lamarck. Stephenson, North Carolina Geol. and Econ. Survey, voL 5, pt. 1, p. 161, pl. 42, figs. 1-5; pl. 4-3, fig. 6 (not figs. 1-5) ; pl. 44, figs. I, 2. 19'l6. Gryphaea vesicularis Lamarck. Wade, U. S. Geol. Survey Prof. Paper 137, p. 58, pl. 17, figs. 1,2; pl. 18, figs. 1, 2; pl. 19, figs. 1, 2. 1929. Gryphaea vesicularis Lamarck. Dane, Arkansas Geol. Survey Bull. 1, pl. 18 (op. p. 94) ; pl. 23 (op. p. 134) • (Figures only.) Shell large, massive, and extremely var­iable in outline and form; in general subcircular to broadly subelliptical in out­line; may become very thick in the senile stage, attaining 60 mm. or more in extreme cases. Left valve ranging from com­pressed, almost fl.at, to strongly convex, the convexity depending to a considerable extent upon the stage of growth; that is, the older the more convex. On most left valves a radiating sulcation extends from the vicinity of the beak backward and downward to the posteroventral margin, and this tends to produce a posterodorsal auriculation; this sulcation varies greatly in strength, being practically absent in some shells, becoming pronounced in others, and in extreme cases the shell hack of the sulcation forms a rugged, prominent, radiating ridge; on occasional shells there is a similar sulcation extending from the beak to the anteroventral margin, which tends to produce a corresponding antero­dorsal auriculation. Right valve flat to strongly concave and overlapped by the margins of the left valve. The posterior auriculation of the left valve, if present, is reflected in the right valve, which bends in to fill the notch produced by the auricu­lation. Beaks as a rule relatively small and nonprominent, located centrally or a little in advance of the center, that of the left valve curving over to the right and overhanging the right beak slightly. The hinge line is typically long, nearly straight, and edentulus; the ligamental area is triangular, the basal or inner border longer than the sides; ligamental groove broad and strongly impressed on left valve, less strongly so on right valve, occupying a third or more of the ligamental area. Inner surface smooth and more or less ir­regular on different individuals. Adductor muscle scar large, deeply impressed, sit­uated above the midheight and a little back of the midlength. A small pedal muscle scar is situated on the inner surface just below the inner end of the ligamental groove of each valve. Surface of left valve marked by incremental lines and by rather coarse growth undulations and imhricating lamellae. Surface of right The University of Texas Publfoation No. 4101 Yaln' similarly marked, the growth lamellae beco1~1ing coarsP and strong toward the outer borders of adults: right rnh-e further marked bv a dozen or more radiating Yery narrow. lines or shallow channels of unequal spacing and strength. Dimensions of the left Yake of the type in the Academy of Natural Sciences of Philadelphia: Length 107 mm., height 99 mm .. thiC'kness 42 mm. Dimensions of a laqre shell from Texas: Length 150 mm., heip:ht l :w mm., thickness about 65 mm. An unusually large right Yalve is 158 mm. long and 135 mm. high. The genus Cryphaea forms a conspic­uous element in the faunas of the Upper Cretaceous series of the Atlantic and Gulf Coastal Plain. The shells are numerous in man~· beds and some of the shells attain large size. They exhibit extreme individual variation and many of them can be as­signed to definite s.pecies only with great difficulty; because manv of the American shells bear a general ;esemblance to the variable sped.es, Cryphaea vesicularis Lamarck. of the European Lpper Creta­ceous. there has been a tendency amoner American authors to refer them t~ Lamarck's species. One species. Crrphaea aucella Roemer, which is sometimes thus included, is not onlv clearly distinct but is. with a few questionable e~ceptions,' con­fined in its range to the Austin chalk, and beds of Austin age. The type of Cryphaea vesicularis Lamarck is a young sheII from the Upper Chalk of Meudon, France (Campanian). As fi~ured it appears to be more convex than the shells of C. mutabilis at the same stage of growth. wroods15 j in his mono­graphic treatment of the English Ostreidae included in Lamarck's sp~cies a large varietv of forms ranging in ar., vol. 3, p. 330, pl. 34, fig. 15. 1858. Exogvra costata Say. Emmons, North Cai·olina Geol. Survey Rept., p. 278, text fig. A. 1860. Exogyra costata Say. Owen, Genl. Survey .Arkansas 2d Ann. Rept., Genl. Recon­naissance :\rkansas, pl. 8, fig. 4. 1868. Exogyra costata Say. Cook. Geol. Survey New Jersey (Geology of New Jersey), p. 374, text fig. 1869. Exogyra torusa 1\lorton. Coquand, Mon. Genre Ostrea Terrain Cretace, p. 38, pl. 14, fi~s. 1-4; pl. 15, figs. 1, 2. Un part.) 1876. Exogyra costata Say. Gabi>, Acad. Nat. S('i, Philadelphia Proc., vol. 28, p. 323. 1884. Exogyra costata Say. ·white, U.S.Ceol. Surwy 4th Ann. Rt·pt., p. 30·1. pl. 56, figs. L 2; pl. 57, figs. 1, 2. lSee also p. 301.) 1885. Exogyra costata Say. \VhitfidJ. U.S.Geol. Sunt:>Y .\Ion.. vol. 9, p. :39, pl. 6, figs. l, 2. ·(Ceol. Survey New .Jersey, Paleon­tolo~y, ml. 1, p. :39, pl. 6, figs. 1, 2, 1886.) 1896. Exogrra costata Say. Bull. Am. Paleon­tology, vol. l, p. 291 (No. ~' p. 2~). (A reprint of Say's paper published m Am. .Tour. S('i. in 18:20.) ?1900. Exogyra costata Say. Harris, Geology of Louisiana, Rt~pt. for 1899, p. 292, pl. 49, fig. 1. 1901. E:rogvra costata Say. Hill. U.S.Geo1. Sur· vey 21st Ann. Rept., pt. 7, pl. 47, figs. 1, la. (Figures only.) 1902. Exogrra costata Say. Hill and Vaughan, U.S.Geol. Survey Geol. Atlas, Austin Folio (no. 76), illustration sheet, fig. 52. (Figure only.) 1906. Exogyra costata Say. Bose, Bol. Inst. Geol. de Mexico, no. 24, p. 51, pl. 6, fig. 3; pl. 7, fig. l; pl. 8, figs. 2, 3; pl. 9, fig. 3. 1906. Exogyra costata Say. Veatch, U.S.Geol. Survey Prof. Paper 46, pl. 11, figs. 2, 2a. (Figures only.) 1907. Exogyra costata Say. Weller, Geol. Survey New Jersey, Paleontology, vol. 4, p. 456, pl. 47, fig. 1. 1911. Exogyra costata Say. Miller, Maryland Gcol. Survey, Prince Georges County, p. 96, pl. 5, fig. 8. (Figure only.) 1913. Exogyra costata Say. Bose, Bol. Inst. Geol. de 1\lexieo, no. 30, p. 51. 1914. Exogvra costata Say. Stephenson, U.S. Geol. Survey Prof. Paper 81, p. 50, pl. 16, figs. 3, 4; pl. 18; pl. 19, figs. 3, 4; pl. 20, fig. l. 1916. Exogyra costata Say. Gardner, Maryland Geol. Survey, Upper Cretaceous (2 vols.) , p. 564, pl. 25, fig. 5; pl. 26; pl. 27, figs. 1, 2. 1923. Exogyra. costata Say. Stephenson, North Carolina Geol. and Econ. Survey, vol. 5, pt. 1, p. 173, pl. 47, figs. 2-5; pl. 48. 1924. Exogyra costata Say. 1ourdy, .Annales Paleontologie, vol. 13, p. 81, pl. l, fig. 2. 1924. Exogyra costata Say. Deussen, U.S.Geol. Survey Prof. Paper 126, pl. 12, fig. 1. Figure only.) 1926. Exogyra costata Say. Stephenson, Geol. Survey Alabama Special Rept. No. 14, pp. 242, 248, pl. 87' fig. 4; pl. 91, fig. 1. (Figures only.) 1926. Exogy.ra costata Say. Wade, U.S.Geol. Sui·vey Prof. Paper 137, p. 56, pl. 15, figs. 1, 2. 1928 . Exogyra costata Say. Adkins, Univ. Texas Bull. 2838, p. 116, pl. 37, fig. 2. 1929. Exogyra costata Say. Reeside, U.S.Geol. Survey Prof. Paper 154, p. 271, pl. 69, figs. 5-8. 1929. Exvgyra costata Say. Dane, Arkansas Geol. Survey Bull. l, pl. 20 (op. p. 108), fig. 2; pl. 26 (op. p. 140), figs. 1, 2. (Fig­ures only.) Shell markedly inequivalve, thick to massive, occasional overgrown specimens becoming ponderous; variable in form, but in general subcircular to subovate in outline. Left valve much larger than the right, strongly convex, spirally incoiled to 11/2 to 2 volutions. The beak is, as a Invertebrate Fossils of the Navarro Group rule, more or less deformed by the scar of attachment, which varies in size on dif • ferent individuals from very small to a maximum measured length of 88 mm. On most shells there is a perceptible umbonal ridge extending from the beak in a curve around to the postero-ventral margin, but some shells are so regular I y rounded that they seem to lack this ridge. The surface is ornamented with regular I y arranged, prominent, radiating, entire or bifurcating costae which in medium-sized specimens extend from the beak to the margin in curves conforming to the twist of the shell. The costae are separated by channels which are as a rule narrower than the costae. In nontypical specimens the costae are weakly developed, and to­ward the margins of the older and larger shells the costae become weak and dis­appear. The costae vary in cross section from semicircular to squarish, and in width from 2 to 8 mm.; the concentric growth features are such as to roughen the costae with rounded nodes and more or less prominent lamellae. Right valve operculiform, flatly spiral, varying from broadly convex to rather strongly concave, the valve inclosed within the projecting margin of the left valve; in some shells the portion in front of the beak is pro­nouncedly convex, and the portion back of the beak more or less concave. Beak small and flatly depressed. Surface or­namented with numerous, concentric, shar2-edged lamellae; on the anterior and ventral parts of the surface these lamellae stand up as sharp-edged ridges separated by deep channels, but centrally and toward the rear the lamellae flatten out giving to this portion of the shell a smooth appearance. Costae wanting on most shells hut faintly developed on some and becoming fairly distinct on the upper posterior third of occasional individuals. The hinge and internal characters are nor­mal for the genus. Dimensions of the medium-sized speci­men shown in plate 19, figure 2: Length 92 mm., height 95 mm., thickness 54 mm. Senile shells become elongated in the di­rection of the height. The largest shell in the collection from Texas, found near Lewis Ferry on Red River, Bowie County ( 12935), is about 118 mm. long and 150 mm. high. One of the largest specimens ever collected, found in the Selma chalk in Kemper County, Mississippi, is 200 mm. high.162 Like most other members of the oyster family, this species exhibits considerable variation in form and in the strength and coarseness of its ornamentation. In Mississippi the species is represented in the lower part of the Exogyra costata zone ( = Exogyra cancellata zone) , chiefly by shells ornamented with strong, rather broad, coarse costae; in the Neylandville marl (Exogyra cancellata zone) in Texas a few well preserved shells of medium size and with costae of medium width have been found (pl. 21, fig. 2), and also a few small, imperfectly preserved, nontypical and fragmentary specimens; on these lat­ter the costae are either narrow or of medium width. Specimens from the Naca­toch sand exhibit costae varying on dif­ferent individuals from medium width to very narrow. Most of the numerous speci­mens from the Corsicana marI have nar­row costae, but on some shells the costae are of medium width; one individual from the marl has broad, coarse costae over part of its surf ace. All the shells of this species from the Kemp clay have narrow costae, and in general these shells are narrower and more elongated in the direc­tion of the height than shells from the lower formations (pl. 19, fig. 1), though here, as in lower formations, the shells vary greatly in form. The shells of this genus from the 0 at at o o r group of India, which Stoliczka163 referred to E. costata, occur at a much lower geologic horizon ( Cenomanian) than does the American species, and it certain! y is a distinct species; the published figures do not justify considering them the same. Types.-Say described this species with­out figuring it, and his type material has apparently been lost. He cites it as having come from the "ancient alluvial deposit of 1811Stephenson, L. W., U. S. Ceol. Survey Prof. Paper 81, p. 51, pl. 18. l&'IStoliczka, F., Geol. Survey India Mem., Palaeontologia lndica, Cretaceous faunas of Southern India, vol. 3, p. 461, pl. 40, figs. 1-3; pl. 41, fig. l, 1871. The University of Texas Publication No. 4101 New Jersey." The species was first figured by Morton in 1828, who states that the figured specimen was lent to him by Sam­uel R. Wetherill, of Burlington, New Jersey. Apparently this specimen was not preserved in any Museum, and it is prob­ably lost. Although so far as known no author after Say saw the type material, the species has been accepted by all authors as a valid one, and costate shells such as those figured in this volume have been referred to it without question. Plesiotypes from Texas, U .S.N .M. nos. 76408, 76409, 76410, 76411. Distribution in Texas.-Navarro group, Neylandville marl: Specimens with costae of medium width from 31h miles northeast of Greenville ( 16158, 1 specimen figured) ; 3 9/10 miles west of Terrell (17379); non­typical, fragmentary specimens from 5 miles northwest of Terrell (14104), and 1 mile east of Gastonia ( 7550) . Navarro group, Nacatoch sand: 8 miles north of New Boston ( 12935) ; vicinity of Kaufman ( 761) ; Watkins' place 3 miles north of Corsicana ( 9552) . Navarro group, Corsicana marl: 2 3/5 miles north by east of Malta (5310, 5432; 12933, 1 specimen figured; 12934, 16159); 11Jt miles south by east of Oak Grove (13568, 16160); 2 miles south of Oak Grove ( 12932) ; 1h mile north of the town of Sulphur Bluff (5321); about 3 miles south-southwest of C am p b e I I (12927); 3 7/10 miles southwest of Campbell ( 1554 7) ; dam on Cedar Creek, 10 miles south-southeast of Greenville (Tex. Bu. 739) ; 1% miles northeast of Quinlan (12928); 1~ft.> miles N. 20°W. of Tona siding ( 15545) ; near Terrell ( 15544) ; west edge of Kaufman ( 7548) ; 4 miles south by west of Kaufman (14100); 7 7/10 miles west of Cameron (14131, 15538); 1/i mile west of Kimbro ( 14129) ; Car Ison farm, Kimbro Survey, Travis County (Tex. Bu. 3033) ; bluff on Cottonwood Creek west of Kimbro (Tex. Bu. 2.320) ; 31/i miles east by north of Manor (14127); 4 miles south of Manor (Tex. Bu. 2399); Onion Creek, 21h miles west of old Garfield (7605, 1 specimen figured; 12920, 14156, 15531; Tex. Bu. 625) ; public road 21h miles west of old Garfield (7604) ; 1 mile southeast of Moore's store, Travis County (Hill coll. 46); near Moore and Berry's store, Travis County (16148); west end of Simpson's Hill on road leading up from Onion Creek ford, Travis County (Hill coll. 47); 1h mile below Martindale ( 7621) ; 1112 miles southeast of Redwood store, Guada· lupe County (7622); 1 3/10 miles north of McQueeney (7637); 1 3/10 miles south-southeast of Marion ( 13389) ; 2112 miles west of McQueeney ( 15523) ; 2 miles east of Marion (Tex. Bu. 2395); near Highway 90, l 1h miles west of Woman Hollow Creek, Bexar County ( 16490) ; Salado Creek upstream from Highway 90, Bexar County (16671); Salado Creek below Hedwig road, Bexar County (16492, 16669); near Camp Travis Hospital northeast of San Antonio (Tex. Bu. 39); well 7/20 mile south by west of St. Mary's University, Bexar County (16353); arroyo, 2/5 mile south by west of St. Mary's University, Bexar County (16354, Tex. Bu. 744); 1 mile south of B.M. 746 on Culebra road, Bexar County (16352); fuller's earth pit 14 miles west of San Antonio ( 15520, Tex. Bu. 7 43) ; Castroville road, 11/5 miles west of Leon Creek, Bexar County ( 15522, Tex. Bu. 746) ; 14 miles west by south of San Antonio (Tex. Bu. 43, 742) ; 6 miles east of Castroville ( 15502, 16156; Tex. Bu. 3282) ; near Castroville (7665, 7796) ; 4 or 5 miles north by west of Castroville (10627, Tex. Bu. 747); 2 miles south of Cliff ( 10870, 1 specimen figured; 17450) ; at depth of 1045 feet in well on G. A. Harper Survey, Medina County (13844). Navarro group, Kemp clay: 12 miles southeast of Greenville (11247); 10 miles northeast of Corsicana ( 9556) ; 61h miles southw~st of Currie ( 14138) ; branch, 61h miles southwest of Currie (14139); 5 miles east of Cooledge (14136); San Gabriel River, 2/5 mile above San Gabriel ( 14130) ; 5 miles west by north of Elgin (14162); 31/,i miles north of Manor ( 13861) ; 4 miles south of Manor (Tex. Bu. 2399) ; 2 miles northwest of Deats· ville ( 14128, 1 specimen figured) ; vicin· ity of Webberville (Hill coll. 8); near Invertebrate Fossils of the Navarro G1·oup Deatsville ( 764, 14125) ; Littig ( 765) ; 4 3/5 miles west of Lytton Springs ( 15529) ; 4 miles southeast of Zorn (10877); near McQueeney (7633); 4fa mile north of Zuehl (16489); west of Zuehl ( 7085) ; Leon Creek valley, 1 mile above the Southern Pacific Rail road bridge, Bexar County (15519). Navarro group, Escondido formation: Uvalde road about 11 miles northeast of Eagle Pass (1885) ; old Batesville road, 5 miles northeast of Chimeneas ranch house, 6 miles southwest of Burke ranch {10284.); bed of a small branch east of the Chimeneas ranch house, 18 miles east of Eagle Pass (8246) ; Uvalde road, 6% miles northeast of Eagle Pass (8258); about 4 miles east of Eagle Pass (609); about 600 yards east of Eagle Pass ( 608) . Ouuide di.stributron.-Arkansas: Sara­toga chalk, Nacatoch sand, and Arka­delphia marl. Tennessee: Coon Creek tongue of Ripley formation. Mississippi: Selma chalk ( Exogyra can­cellata zone and upper part), Ripley formation, Owl Creek formation, and Prairie Bluff chalk. Central and west-central Alabama: Selma chalk ( Exogyra cancellata zone and upper part), Ripley formation and Prairie Bluff chalk. East-central Alabama and Chatta­hoochee region (Alabama-Georgia): Rip­ley formation and Providence sand. The Carolinas: Peedee formation. Maryland: Monmouth formation. Delaware: Mount Laurel sand. New Jersey: Mount Laurel sand, Nave­sink marl, and Red Bank sand. Mexico: The species is known to occur in the continuation of the beds of the lower part of the Escondido formation southward in the State of Coahuila, Mexico. B0se1 " has recorded the species from the Senonian of Coahuila, hut he did not dis­tinguish between the varietal form of the species, ExoGYra costata var. spinifera, which occurs in the San Miguel formation and in the southward extension of the San Miguel in Coahuila. It is probably the varietal form which occurs in his so-called lower Senonian, which includes the San U15ee •JDODJmJ. 1913. Miguel beds. Bose163 has also recorded the species from Upper Cretaceous beds near Cardenas, State of San Luis Potosi, Mexico. Colorado: Reeside166 has described and figured a few small imperfectly preserved specimens of Exogyra from either the Rocky Ridge or the Larimer sandstone member of the Pierre shale of Upper Campanian age in northeastern Colorado, which appear to he fairly good representa­tives of Exogyra costata Say, though they are not strictly typical of the species. Range.-The species is considered to he virtually restricted in its range to the Exogyra costata zone, which in Texas in­cludes all of the Navarro group. Speci­mens which approach rather closely to the more typical costate forms are occasionallJ found in the Exogyra ponderosa zone, hut these exceptional specimens are all smalle1 and exhibit differences in form and other characters from those of the higher zone; most of them exhibit the spinose characters in greater or less degree, which distinguish E. costata spini/era from the typical E. costata; they may well be the progenitors of E. costata Say. EXOGYRA COSTATA SPINIFERA Stephenson, n. name Pl. 21, fig. 1 1914. Exogyra costata Say. Stephenson, U.S.Geol. Survey Prof. Paper 81, pl. 17, fig. 2; pl. 19, figs. 1, 2. (In part.) 1923. Exogyra costata var. spinosa Stephenson, North Carolina Geol. and Econ. Survey, vol. 5. pt. 1, p. 179, pl. 49, figs. 1-6; pl. 50, figs. 1-4. (Preoccupied.) Not E. spinosa Matheron. As the name spinosa, which was origin­ally proposed for this variety, is pre­occupied for a species of Exogyra in beds of Cenomanian age in France, 167 the name Exogyra costala spinifera is herewith pro­posed to replace the preoccupied one. The left valve of this variety differs from the more typical representatives of the species in the prominent development of concentric growth lamellae which, along the crests of the costae, are upfolded into 185See synonymy, 1906. 188See •ynonymy. 18'1Matheron. M. Philippe, Catalogue Meth. et Deac. des Corps Orpn. Fossile. du Dep. dea Douches du Rhone, Marseille. p. 192. pl 32. figs. 6. 7, 1842. The University of Texas Publication No. 4101 spine-like projections. The folds vary in prominence, but reach maximum heights of 6 or 8 millimeters above the costae; they are easily broken, so that all speci­mens are imperfect. The spines may be distributed over most of the surface of the left valve, as in the holotype, and the one shown in Plate 21, figure 1 of this volume, or they may be present only over parts of the surface. The right valves vary in form and sculpture on different individuals; they range from flat or con• cave, to strongIy convex and massive; some lack costae and projecting folds, while others have them rather strongly developed on the posterodorsal part of the surface; on some specimens the concentric lamellae on the anterior and ventral por­tions of the surface are distinctly wavy. The dimensions of the shell shown in Plate 21, figure 1, are: Length 83 mm., height 78 (? ) , thickness 54 mm. The larg­est shell from Texas is 110 mm. high. Specimens which combine the characters of Exogyra ponderosa var. erraticostata Stephenson and E. costaJ,a spinifera are not uncommon in the E. ponderosa zone, and some individuals can be assigned to one or the other variety only with difficulty. In­deed the relationships among E. ponderosa, E. costata, and their varieties, seem to sug­gest the following evolutionary history of the group: The variety erraticostata evolved from the smooth E. ponderosa; the variety spinifera evolved from errati­costata; and the typical E. costata evolved from spinifera. The latter variety did not cease to exist with the appearance of the typical E. costata but continued to live alongside of it for some time, the costae becoming more regular from generation to generation. Type.-Collection of the U.S. National Museum, cat. no. 31231; from lower part of Peedee formation, at Robinson's Land­ing, Cape Fear River, North Carolina. One plesiotype from Texas, U.S.N.M. no. 76413. Distribution in Texas.-Taylor marl: Colorado River, 1 mile northeast of Del­valle, Travis County (12892) ; a small arroyo 1/3 mile east of the Staples store road, 2%, miles south of San Marcos, Hays County (7617); San Marcos River below the mouth of Blanco River, Hays County ( 7618) ; San Marcos River, 3 miles south­east of San Marcos (7620) . Anacacho limestone: A cliff 1/5 milfl north of Cliff, Medina County (12906) . Anacacho Mountain, 5 miles southwest of Cline (Uvalde County) , in Kinney County (7718); bluff on Muela Creek at Flowers ranch house, Kinney County ( 8266) . San Miguel formation: Scarp on the Carter ranch, overlooking the Rio Grande, 12 miles northwest of Eagle Pass, Maverick County (8227); Del Rio road, 12112 miles northwest of Eagle Pass, Maverick County (8226); northward-facing slope of Agua de Fuera Creek valley, 5 miles southeast of Spofford, Kinney County (8262) ; a tank 1h mile east of the Uvalde road, 18 miles northeast of Eagle Pass (8249). Navarro group, Neylandville marl: 1 7/10 miles south of Burlington (14133); 1 mile west of Pettibone station (14132, 15540). Navarro group, Corsicana marl: 4 or S miles north by west of Castroville (10627, 1 specimen figured) ; 2 miles south of Cliff (10870). Outside distribution.-Arkansas: Ozan formation and upper part of Marlbrook marl. Northern Mississippi: Upper part of Coffee sand and Selma chalk (Exogyra cancellata zone). The Carolinas: Snow Hill member of Black Creek formation and Peedee forma­tion ( Exogyra cancellata zone) . New Jersey: In the collection of the Academy of Natural Sciences of Phila· delphia is a fairly good example of this variety labeled "Exogyra costata Say, Burlington County, N.J., received from Dr. Chas. H. Budd." Range.-In Texas the variety first ap· pears sparingly well down in the Taylo1 marl and beds of Taylor age, and ranges upward into the Corsicana marl of the Navarro group. Superfamily TRIGONIACEA Family TRIGONIIDAE Genus TRIGONIA Bruguiere, aenau Jato The name Trigonia is here used in ite broad sense. . 1:he genotype accepted by , Stewart,168 Dietnch,169 and others (but not · 108Stewart, Ralph, Acad. Nat. Sci. Philadelphia Special Pub. no. 3, pp. 88·90, 1930. 189Dietricb, W. 0., S:tzungsberichte der Gesellschaft. Naturforscbender Freunde zu Berlin, pp. 326-332, 1933. Invertebrate Fossil& of the Navarro Group by Crickmay1To) is Trigonia nodulosa Lamarck ( 1801). If the new group names proposed by Deecke111 in 1925, and fav­ored by Stewart, 1T2 and later by Dietrich, 1Ts be adopted, the Upper Cretaceous Trig­onias described in this paper would appear to fall in the genus Scabrotrigoma Deecke, the genotype (designated by Dietrich) of which is Trigonia scabra Lamarck from the Cretaceous of France. I have not been able to determine from the poor figures of Van Hoepen,1u to which ones, if any, of his African genera the Texas species belong. TRIGONIA STANTONI Stephenson, n.sp. Pl. 20, fig. 3 Shell of medium size, equivalve, in­equilateral, subtrigonal, moderately ven­tricose anteriorly, becoming compressed posteriorly. Beaks small, incurved, opis­thogyrate, situated only slightly back of the anterodorsal extremity. Hinge and other internal features concealed in the type material by hard sandstone matrix, except the upper side of the posterior tooth of a right valve, which is strongly striated normal to the plane of contact of the two valves. Anterior and ventral mar­gins broadly and evenly rounded, the latter fullest anteriorly, rising high pos­teriorly to meet the short, subtruncated, oblique posterior margin; the ventral margin is coarsely notched, each notch corresponding to an intercostal space; dorsal margin broadly concave. The dorsal surface of each valve is a broadly concave hand normal to the plane of con­tact of the two valves; in the holotype this hand is 45 mm. long, and has a maximum width of 6 mm.; the band is ornamented with a series of rather rugged, fairly sharp-crested, transverse ridges; at their outer ends these ridges bend down and forward 1 to 6 mm., to a radiating groove which separates this dorsal area l'°Crickmay, C. H•• Amer. Jour. Sci•• 5th aer., vol. 24, pp. 446.453, 1932. 1T1DeecJce, W., Palaeonto)ogiscbe Zeitacbrift, Band 7. Heft 2, p. 68. 1925. ll'IStewart, Ralph, op. cit., p. 89. lDDietrich, W. O•• op. cit., p. 330. 11'Van H<'epen, E. C. N., Paleontologiese Navoraing van dfe Mueum, Bloemfontein, Deel I, Erste Stuk, 38 pp•• 7 pll.., 19'J9. from the main surface of the shell. The latter is ornamented with 15 or 16 radiat­ing ribs which centrally are strong, rugged and coarsely nodose, and are separated by wide deep interspaces; anteriorly the suc­cessive ribs become weaker and the same is true posteriorly; posteriorly the ribs become more and more oblique, the last ones approaching a horizontal position; they also have a broad curve, convex upward, in their trend; the 9 or 10 anterior ribs may be traced upward and forward well toward the beak and presumably they connect with the transverse ribs on the dorsal area; the 6 or 7 posterior ribs come to an end along the radiating groove which separates the main surface from the dorsal surface. Approximate dimensions of the holo­type, a somewhat imperfect left valve: Length 63 mm., height 52 mm., convexity 16mm. This species differs from Trigonia th.oracica Morton, from the Prairie Bluff chalk in Alabama, chiefly in its fewer, coarser and more oblique ribs. The species has a close analogue in the shell from the Ripley formation (Coon Creek tongue) at Coon Creek, Tennessee, which Wade175 described under the name T. thoracica, but which is obviously not that species. Wade's species differs from T. stantoni, in its nar­rower, sharper, and less coarsely nodose ribs, and in the steeper upturn of its posteroventral margin. The shell from the Marshalltown forma­tion of the Matawan group of New Jersey, which Weller176 referred to T. thoracica, is too coarsely ribbed for that species, and is a shorter species than either T. thoracica or T. stantoni. Types.-Holotype, U.S.N.M. no. 76416; 3 unfigured paratypes, U.S.N.M. no. 76417; 4 unfigured paratypes, U.S.N.M. no. 76418. Distribution in Texas.-Navarro group, N acatoch sand: Vicinity of Corsicana ( 763, loc. of holotype and 3 unfigured paratypes); north edge of Corsicana (518, loc. of 4 unfigured paratypes) ; north of Rock Branch 3 miles northeast of Corsi­ cana ( 9560) ; vicinity of Chatfield ( 762) . 175Wade, Bruce. U. S. Geol. Survey Prof. Paper 137, p. 60, pl. 20, figs. l, 2, 1926. 176Weller, Stuart, Geol. Survey New Jersey, Paleontology, vol. 4, pl. 48, figs. I, 2, 1907. The University of Texas Publication No. 4101 TRIGONIA CASTROVILLENSIS Stephenson, n.sp. Pl. 19, fip;~. 3-7 Shell of medium size, equivalve, inequi­lateral, moderately ventricose anteriorly, becoming compressed posteriorly. Beaks small, incurved, approximate, slightly opisthogyrate, situated a little back of the anterodorsal extremity. Hinge of right valve with two prominent thin, transversely striated teeth diverging from the beak, with a deep triangular space between open­ing into the interior; the anterior tooth is the shorter and thicker of the two and is supported by a thick platform which is deeply sunken below the margin of the shell. Two deep, diverging, striated sockets on the hinge of the left valve ac­commodate the teeth of the right valve; these sockets are separated by a very prom­inent, thick, bifid tooth which fits into the triangular space separating the teeth of the right valve; the outer margin of each socket is bordered by a sharp, nonprominent carina. The anterior adductor scar on the right valve is small and narrow, and oc­cupies the end of the platform on which the anterior cardinal tooth is seated; the anterior adductor of the left valve is seated on a thick deeply submerged platform which protrudes from the side of the shell just below and a little in front of the inner end of the anterior tooth socket; the pos­terior adductor scar is small. triangular and situated high in the shell; a small retractor muscle scar lies closely above the adductor. Inner posterior surface divided by a short, sharp, longitudinal ridge which comes to the truncated posterior margin near its center. Ligamental grooves short but deep and narrow. The dorsal area back of the beaks is normal to the plain of contact of the two valves, is broadly con­cave from front to rear and is 24 mm. long and 6 mm. wide in the holotype; a well defined radiating sulcus. which extends from the beak to a point slightly above the middle of the posterior truncation, ap­proximately separates the dorsal ornamen­tation from that of the main body of the shell. The dorsal area is crossed trans­versely by 14 or 15 prominent ribs, sep­arated by wider interspaces; at the outer margin of the dorsal area each rib bends forward and downward, becoming smaller, and joins the upper end of a lateral rib at an acute angle a little above the radiat. ing sulcus. The anterior margin rounds down reg· ularly into the rather full ventral margin which curves up sharply posteriorly; posterior margin obiiquely truncated above the midheight, meeting the hinge line at an angle 125 degrees; dorsal mar· gin broadly concave. The main surface of each valve is ornamented with about 20 radiating, acute, spinose ribs which decrease in strength and in length both anteriorly and posteriorly; many of the spines are brokn away but a few unbroken spines are bluntly rounded and rise to maximum heights of 2.5 or 3 mm. above the crests of the ribs. Along a line some· what below the posterodorsal radiating sulcus the upper part of each of the lateral ribs bends forward in a broad curve or broad obtuse angle, becoming much smaller and spineless, and meets a rib of the dorsal surface at an acute angle a little above the sulcus; several additional fine, spineless, radiating ribs intervene be­tween the last of the coarser ribs and the sulcus. Dimensions of the holotype: Length 44 mm., height 37 mm., thickness about 30 mm. Compared with Trigonia stantoni, this species has more and finer ribs, and the ornamentation on the dorsal and postero· dorsal areas is much finer; the shell also bends up in a somewhat stronger curve posteriorly. T. thoracica Morton is a more elongated species with fewer ribs, the finer ornamentation of which is too incom· pletely preserved on the types for critical comparison. Types.-Holotype, U.S.N.M. no. 76419; 2 figured paratypes, U.S.N.M. no. 76420; 8 selected unfigured paratypes, U.S.N.M. no. 76421. Distribution in Texas.-Navarro group, Corsicana marl: Near Castroville (7665, loc. of holotype) ; well 7 /20 mile south by west of St. Mary's University, Bexar County (16353, loc. of 2 figured and 8 unfigured paratypes; 16408); arroyo 2/5 mile south by west of St. Mary's Uni· versity, Bexar County (16354; Tex. Bu. 744) ; 1 3/10 miles south-southeast of Invertebrate Fossils of the Navarro Group Marion (13389); poorly preserved molds questionably referred to the species were found in No. 1 Redus well, G. A. Harper 92-acre survey, Medina County (13844); ?4 or 5 miles north by west of Castroville (Tex. Bu. 747). TRIGONIA EUFAULENSIS GABBI Stephenson, n.var. Pl. 19, figs. 8, 9 Shell relatively small, equivalve, in· equilateral, subtrigonal, strongly ventri· <;ose anteriorly, becoming strongly com­pr~in the posterior third of the length. Beaks small, incurved, approximate, sit­uated only a few millimeters back of the anterodorsal extremity. Hinge concealed. Adductor scars deeply impressed, the posterior one the larger. Pallial line sim­ple with the exception of a shallow inward swing where it passes up to meet the distal end of the posterior adductor scar. Inner posterior surface nearly equally divided by a short, pronounced longitudinal ridge which comes to the margin about midway of the short posterior truncation. Anterior margin broadly rounded, passing reg­ularly down into the rather full ventral margin which in tum curves up steeply, becoming slightly concave as it approaches the distal end of the shell; posterior mar­gin short, truncated, strongIy inclined forward; dorsal margin broadly concave. A narrow radiating channel or sulcus ex­tends from the beak to about the middle of the posterior truncation, approximately separating the dorsal from the lateral or­namentation. The broadly concave dorsal band is about 2 mm. wide centrally, and is crossed by 14 or 15 sharply defined transverse ridges; at their outer ends these ridges tum downward and forward and, though not well preserved, each ridge seems to meet the upper end of a cor­responding lateral rib at an acute angle near the radiating sulcus. The lateral ribs, which number 15 or 16, are strongest centrally and, with the exception of 3 or 4 of the posterior ones, they curve around rather strongly toward the front as they approach the ventral margin; the crests of the ribs are broken into bluntly rounded upper end each of the ribs becomes smaller and bends forward at an obtuse angle meeting one of the dorsal ribs at an acute angle. Dimensions of the holotype, a right valve: Length 32 mm., height 25.5 mm., convexity about 9 mm. This variety differs from the typical T. eu/aulensis Gabh in its greater propor­tional height, in its greater breadth in the upturned posterior portion of the shell, and in its fewer and less strongly curved lateral ribs. It is a much more coarsely ornamented variety than T. eufaulensi.s 1noorei. Types.-Holotype, U.S.N.M. no. 76423; 1 figured paratype, U .S.N .M. no. 76424; 3 unfigured paratypes, U.S.N.M. no. 20955. Distribution in Texas.-Navarro group, N acatoch sand: Vicinity of Kaufman (761, type loc.) ; northwest corner of Franklin County (12931) ; 6 miles south­east of Cooper (12929). TRIGONIA EUFAULENSIS MOOREI Stephenson, n.var. PI. 20, figs. 4, 5 The type specimens of this variety are moderately well preserved external molds of a left and a right valve. On these the ribs are somewhat more numerous and more closely spaced, and the finer ribs on the dorsal and posterodorsal surfaces are sharper, and are not so completely broken into fine nodes, than are the cor­responding features on the typical T. eufaulensis Gabb. The ornamentation is in general much finer than on the variety, T. eu/aulensis gabbi. Approximate dimensions of the holo­type, a left valve: Length 20 mm., height 16 mm., convexity not measurable. Types.-Holotype, U.S.N.M. no. 76425; 1 figured paratype, U.S.N.M. no. 76426; 3 unfigured paratypes, U.S.N.M. no. 76427. Named for Mr. Wm. H. Moore, the original owner of the survey hearing his name. Distribution in Texas.-Navarro group, Corsicana marl: About 5 miles east by north of Greenville (12924, type loc.) ; nodes of medium coarseness; toward its 3 7/10 miles southwest of Campbell The University of Texas Publication No. 4101 fl S547 '1 ; 1,{> mile below Martindale l15527). Unidentified specimens of TRIGONIA An incomplete external mold of a medium-sized left valve of Trigonia (pl. 20, fig. 6) from the Neylandville marl in a cut of the Texas l\Iidland Railroad, V~ mile north of Cooper, Delta County ( 14062, U.S. N .M. no. 764.28), differs from T. stanloni in the finer character of the nodes surmounting the radiating ribs, in which respect it is more like the shell from the Ripley formation on Coon Creek, Tennessee. which "\\Tade1 jj described under the name T. thoracica Morton. An in­ternal mold of a right valve in the same lot probably belongs to the same species. Two internal molds of about the same size, from the same zone, near Cooper (4061,, U.S.N.M. no. 76429), present no diagnos­tic specific characters. Several fragments of Trigonia from the Kemp clay near Deatsville, 2 miles north­west of Webberville, Travis County ( 764, U.S.N.M. no. 21184), are too incomplete for satisfactory identification, but enough of the ornamentation is preserved on the dorsal and posterodorsal areas to indicate that the material does not represent either T. stantoni or T. castrovillensis, and probably belongs to an undescribed species. T'"'·o fragments that probably represent this same undesrribed species lvere found in the Kemp clay on Cibolo Creek, 1 1 ,.~ miles west of Zuehl, Bexar County (7721, l!.S.N.M. no. 76-130). Superfamily PECTINACEA Family PECTINlDAE Genus PECTEN Millier, sensu lato The family Pcctinidae is represented in the Navarro ~roup by 10 species, which an~ referable more or less questionably to at least 6 subgenera, one of which is new. The L p1wr Cretaceous Peciinidae are in need of rnonogra phic treatment. Subgenus PECTEN MiiUer, 1776 Type ~pecie~.-Pcctcn max11num 'Li n n e) (== "Ostrt·a" maxima Linne. desig­ nated hy Schmidt, Yer!'uch, Conch.­ 177\\".idt', Bruer, l'. ~, <>ol. S11n·,,y Prof. Paper 137, p. on, pl. :!O, fi;:!'. L :.!. 1')26. Samml. 1818, p. 67, and by Children, Lamarck's Gen~ra Shells, 1823, p. 66, fig. 89. Of the t<>n species of Pectinidae only one typical is as~igncd, Pectens. questionably, to the PECTEN (PECTEN?) VENUSTUS Morton (variety?) Pl. 22, figs. 3-6 1833. Pectcn venustus Morton, Am. Jour. Sci., 1st ser., vol. 23, p. 293, pl. 5, fig. 7. 1834. Pecten vcnustus Morton, Synopsis of the organic remains of the Cretaceous group of the United States, p. 58, pl. 5, fig. 7. 1885. Pecten venustus Morton. Whitfield, U.S. Geol. Survey Mon., vol. 9, p. 45, pl. 7, fif!s. 1-4. ( Geol. Survey New Jersey, Paleontology, vol. l, p. 45, pl. 7, figs. 1-4, 1886.) 1905. Perten venustus Morton. Johnson, Acad. Nat. Sci. Philadelphia Proc., vol. 57, p. 11. 1907. Pecten vcnustus Morton. Weller, Geol. Survey New Jersey, Paleontology, vol. 4, p. 478, pl. 51, figs. 1-5. 1916. Pecten 1·enustu.s Morton. Gardner, Mary­land Geol. Survey, Upper Cretaceous (2 vols.), p. 591, pl. 34, figs. 6, 7. (In part.) 1923. Pertcn venustus Morton. Stephenson, North Carolina Geol. and Econ. Survey, vol. 5, p. 204, pl. 57, figs. 1-5. The description which follows is based mainly upon 3 left valves and 1 incom­plete right valve from the Corsicana marl near Marion, Guadalupe County. Shell small, subcircular in outline, subequi­lateral, inequivalve, thin in the umbonal region. Beak small, not projecting above the hinge line, situated slightly back of the midlength. About the posterior three· fourths of th~ one available right valve is preserved; this shell is ornamented with 15 medium to strong, broadly rounded to squarish-topped ribs, three of which from the center forward are more or less bifid; tlw ribs are crossed by fine incrementals, and toward the dorsal. and posterior parts each rib is surmounted by a row of small wPak nodes; ribs are weak or wanting on a small area near the margin of the posterodorsal slope; the ears are broken away. On a small right valve from Bexar County the right ear is separated from the main shell by a sharp radial sulcus termi· nating in a moderately deep byssal notch; this ear bears 2 or 3 weak radial costae. Invertebrate Fossils of the Navarro Group The left valves are depressed convex and are ornamented with 17 to 20 narrow sharply developed full length ribs, sepa­rated by wider interspaces, and a few small intercalated ribs may appear toward the margin; the ribs are elegant!y ornamented with small crestal spines formed by the upfolding of thin growth layers; these spines number about 3 to the millimeter. The incrementals are fine and sharp. The anterior ear of the left valve is larger than the posterior ear and is ornamented with 2 or 3 rather weak costae; it is separated from the main part of the shell by a pro­portionately wide radial sulcus of mod­erate depth. The posterior ear is ribless and rounds up to the main shell surface. The hinge is narrow and edentulus, but one or two weak crural ridges are present subparallel to the hinge line. The ribs are reftected on the interior of both valves. Dimensions of one of the left valves: Length 7.3 mm., height 8.1 mm., convexity about 2 mm. Dimensions of another of the left valves: Length 7.9 mm., height 7.8 mm., convexity about 1.5 mm. The shells of this species from different localities, and even from a single locality, exhibit some variation in outline, in the degree of bifurcation of the ribs, and in the development of intercalated ribs, but on the whole the group is a compact and well characterized one; it may later he possible to subdivide the group when a more adequate supply of material becomes available. The figured shells from Texas have fewer and coarser ribs than have the cotypes, and perhaps should be treated as a variety. Types.-Cotypes, Academy of Natural Sciences of Philadelphia; 4 right valves, including the one originally figured by Morton. From "New Jersey." Three plesiotypes from Texas, U.S.N.M. no. 764.31. Distribution in Texas.-Navarro group, Nacatoch sand: ?Near Avery (13534). Navarro group, Corsicana marl: 2 miles east of Marion (Tex. Bu. 2395, 3 speci­mens figured) ; well 7/20 mile south by west of St. Mary's University, Bexar County ( 16353) . Navarro group, Kemp clay: ?4 miles southeast of Zorn (10877). 0 u ts id e distribution. -Mississippi: Prairie Bluff chalk and Owl Creek forma­tion. Alabama : Prairie Bluff chalk. South Carolina: Peedee formation (well at Charleston, at depth of 1540 to 1550 feet, probably Exogyra cancellata zone). Delaware: The reported occurrence of the species in the Matawan group of Dela­ware is questionable. New Jersey: Questionably from the Marshalltown formation of the Matawan group, and from the Navesink marl and the Redbank sand of the Monmouth group. Range.-With the exception of the ques­tionable occurrence of the species in the Marshalltown formation of New Jersey, and its reported occurrence in the Mata­wan formation of Delaware, it is restricted in its known geologic range to the Exogyra costata zone, chiefly the upper part of that zone, in the Atlantic and Gulf Coastal Plain. Subgenus CAMPTONECTES Agassiz in Meek, 1864 Type species.-Pectcn lens Sowerby. According to Article 21 of the Inter­national Rules, Agassiz (not Meek) is the accredited author of this subgenus (Meek, Smithsonian Misc. CoM. No. 177, p. 39, 1864). PECTEN (CAMPTONECTES) BUBONIS Stephenson, n.sp. Pl. 21, figs. 3-6 ?1916. Pecten argUlensis Conrad. Gardner, Maryland Geol. Survey, Upper Creta· ceous (2 vols.), p. 588, pl. 34, figs. 3-5. Shell thin, subcircular in outline, suh­equilateral, suhequivalve, depressed con­vex. Beaks small, direct, depressed, scarce! y projecting above the hinge line, situated at about the midlength of the shell. Hinge straight, more than half as long as the shell, with I or 2 long, parallel crural ridges which interlock on opposite valves, and a deep central, triangular resilifer in each valve. The anterior ear of the right valve is longer than the posterior one and is separated from the main body of the shell by a deep anterior hyssal notch, and by a narrow, deep chan­nel which extends from the notch to the The University of Te:rns Publication No. 4101 hinge margin at the beak; anterior ear of ldt rnh-e a little larger than the posterior one: each of the four ears sharply sepa­rated from the main body of the shell by a radiating sulcus: these suki di,·eqre from the beak at an angle of about 96 degrees, and are slightly concaYe upward in their trend away from the beak. The surface is orname~ted with numerous, crowded, nearly flat-topped, low. radiating bifurcat­intr ribs which are separated by much nar­rower, sharp depressions; the ribs are somewhat irregular in their trend, and quite irregular in their width, which aYer­ages less than 0.5 mm., and rarely ex­ceeds that amount; the ribs on the ears are similar to those on the body of the shell, though in general somewhat more irreg­ular, and those on the anterior ears are finer. The surface exhibits fine concen­tric growth lines. but a few remnants in­dicate that in addition to these the surface originally po s s es s e d thin, concentric lamellae spaced 0.5 to 2 mm. apart. which outwardly curwd downward, touching the shell, thus forming round-crested, crenu­lated ridges. the crenulations correspond­ing to the radiating ribs (see pl. 21, fig. 5) ; on most shells practically no evidence remains of the former existence of these ridges. Dimensions of the holotype, a right rnlw from Mississippi shown in plate, 21. figure 3: Length 27 mm., height 27 mm.. co1n-exitY about -l mm. Because of their fine state of preserYa­Lion shells from the Owl Creek formation at Owl Creek. 21 ·> mile5 northeast of Rin­ley. Tippah Cou;1ty. 1\1 ississi ppi, are s~­le~'ted as types. The Texas shells are seareel~-distinguishable from the Missis­sippi one:o-. though the ribbing a\·erages a Iitt le finer. Pcctcn (Cam ptonectes) argillensis Con­rad.17 the type of which came frum some­when~ in Tippah County. Mississippi, is a much ~moother shell, as described and il­lustrated. and has a much wider anale of t"" din·qrence at the beak; the whereabouts of the type is unknown. 17~Conra.!. T . .\.. . .\cad. :\at. Sei. Phila,1.,Jphia Jour.. 2d 5.-r. • ,·ol. I. p. :!8:~. pl. -17. fii:. 3. 18o0. I:'t't' Am<'r. Jour. ~Ci.. \OJ. :J, r. 99, ]869.) Pecten (Cam ptorzectes) bellisculptw Conrad. which se\·eral authors have re­garded as synonomous with P. argillensis, is a distinct species ('haracterized by fine dist in ct radiating ~culpturc all over the surface. The shell from the lower part of the Ripley formation at Coon Creek, Ten­ne:see, which '\\:-ade referred incorrectlv 0 to P. argillensis, exhibits much finer sculpture than that of the present species, and in this respect is more like P. bellisculplus Conrad. The shell described bv Gardner from the l\Ionmouth formatio~ of Maryland under the name P. argillensis Conrad, is like P. bu bom's except that the radiating ribs are more subdued, producing a smoother surface. Pecten virga.tus Nilsson,179 from the Cenomanian of France, and Pecten (Camptonectes) curvat,us Geinitz,180 from the Cenomanian of England, are closely related species. T_rpes.--Holotype~ a right valve from the Owl Creek formation, Owl Creek, 2% miles northeast of Ripley, Mississippi, CS.:\.l\·f. no. 76432; 2 figured paratypes, U.S.:\.?vI. no. 76433; 5 selected unfigured paratypes, U.S.N.:M. no. 76434; 1 example from Texas~ U.S.N.M. no. 76435. Distribution in Texas.-Navarro group, Corsicana marl: About 5 miles east by north of Green\'ille (12924) ; about 4 miles east-northeast of Greenville (] 0886 ·1 ~ 1, ~ mile below Martindale (7621, 15526. 15527) : 1 3 / 10 miles north of McQueeney (7637, 1 specimen figured; ] 552--1-) : 1 3 10 miles southeast of Marion (133891. :\aYarro group~ Kemp clay: Near Deats­,·ille (76-l) ; ?near old Garfield (7603) ; 11 ~ miles northwest of Texas Hill, Travis County (15533) ; 2 7 18 miles west south· west of Staples (10878) ; west of Zuehl ( 7035) : --1-5 mile north of Zuehl (16489). \"aYarro group, Escondido formation: Questionably on eastward-facing slope of l\Iedina Riwr valley, 2 miles below (?) l7'JD·Orbign~·. AL-id.-. Pali-ontolo;,de Franc;aise, Terrain Cn~tacc. ,·ol. 3. p. 602. pl. -Bl, fig3. 7.10, 18-13-1847. 1~0Woods, H"'nry. . -\ monoi.;:rap!1 of the Cretaceous Lame)· libranc:;ia of F.n!!land. vol. I, p. 159, pl. 29, figs. 7a, b, and pl. 3i. fig. 16, 1901. Invertebrate Fossils of the Navarro Group Castroville, Medina County ( 589) ; ques­tionably 2 miles northwest of Nueces River crosaing of Eagle Pass-Uvalde road, Uvalde County (1759). Outside distribution.-Mississippi: Owl Creek formation. East~ntral Alabama and Chattahoochee region (Alabama-Georgia) : Providence sand. Maryland: Monmouth formation. Ran.ge.-The species has been satisf ac .. torily identified only from the Navarro group and formations of Navarro age, that is from the Exogyra costata zone. Closely related species, however, range downward through the Exogyra ponderosa zone, and perhaps still lower. PECTEN (CAMPTONECTES) KAUFMANENSIS Stephenson, a.ap. Pl. 21, figs. 7-9 Shell small, very thin, subcircular in outline, subequivalve, subequilateral, both valves moderately convex. Beaks small, incurved, scarcely rising above the hinge line, situated at about the midlength of the shell and a little back of the mid­leagth of the hinge; there is a faint twist of the beak and the umbonal portion of the shell toward the front. Anterior ears much larger than the posterior ones, and separated from the main body of the shell by narrow rather deep sulci; correspond­ing sulci on the posterior ears are shal­low and not very well defined. Byssal sinus on anterior right ear deep and nar­now, and the sulcus which extends from this sinus to the beak is deeper and broader than the corresponding sinus on the left ear. Hinge edentulous, but pre. smting a long narrow crenulated chan­nel parallel to and closely bordering the hinge line. Resilifer not clearly seen. The available specimens are all internal molds from which the shell material is practically gone, but small portions ad­hering to two specimens, one a right and the other a left valve, show the surface to be ornamented with fine, close-set, low, broad-topped ribs of the kind seen on P. buboni& Conrad, but very much finer and fainter. Dimensions of the larger figured left valve: Length 8.5 mm., height 8.6 mm., convexity 2 mm.? Dimensions of the figured right valve: Length 7.1 mm., height 7.3 mm., convexity about 1.5 mm. This species is about as large as P. simplicius Conrad, but it is much more convex, has a much deeper byssal sinus, exhibits a slight forward twist in the umbonal region, and is ornamented with faint costae. Types.-3 figured cotypes, U.S.N.M. no. 76436; 6 unfigured cotypes, U .S.N .M. no. 76437. Distribution in T exas.-Navarro group, Nacatoch sand: Vicinity of Kaufman ( 761, type loc.) ; 4 miles north of Cor­ sicana ( 17366) . Sub•enus SYNCYCLONEMA Meek Type species.-Pecten halli Gabb (=Pecten rigida Hall and Meek), Meek, Smith· sonian Misc. Coll. No. 177, p. 31, 1864. Pecten rigida Hall and Meek181 is de­scribed as having the surf ace of the right valve marked with concentric ridges and furrows, and that of the left valve smooth. Should the two valves prove to belong to different species, as seems probable, it would be necessary to select one of them as the type of rigi,da. This leaves the true nature of the subgenus in doubt until the selection has been made. PECTEN (SYNCYCLONEMA ?) SIMPLICIUS Conrad Pl. 20, figs. 10, 11 1860. Pecten simplicius Conrad, Acad. Nat. Sci. Philadelphia J our., 2d ser., vol. 4, p. 283, pl. 46, fig. 44. 1864. Sincyclonema? simplicus (Conrad). Meek, Smithsonian Misc. Coll., vol. 7, no. 177, p. 7. 1876. Sincyclonema simplicius (Conrad) . Gabb, Acad. Nat. Sci. Philadelphia Proc., vol. 28, p. 319. 1885. Amusium simplicum (Conrad). Whitfield, U.S.Geol. Survey Mon., vol. 9, p_. 51, pl. 7, figs. 11, 12. (Geol. Survey New Jer­sey, Paleontology, vol. 1, p. 51, pl. 7, figs. 11, 12, 1886.) 1907. Pecten simplicius Conrad. Weller, GeoL Survey New Jersey, Paleontology, vol. 4, p. 480, pl. 51, fig. 6. 1916. Pecten simplicius Conrad. Gardner, Mary­land Geol. Survey, Upper Cretaceous (2 vols.), p. 595, pl. 34, figs. 8, 9. 1923. Pecten simplicius Conrad. Stephenson, North Carolina Geol. and Econ. Survey, vol. 5, pt. 1, p. 199, pl. 55, figs. 6-11. 181ffall, Jame.. and Meek, F. B., Amer. Acad. Arts and Sci. Mem., n. aer., vol. s. p. 381, pl. 1, fi&•· 4&-c, 1856. 19:?6. Pcl'fcn sim plfrius Conrad. ·wadt~. U. S. CeoI. ~urwy Prof. Paper 137. p. 6:?, pl. 20. fig. 7. Sht>ll smal1. thin and papery, subt'ir­cular to broadh-subon1te in outline, the height in some. specimens being slightly oTeater than the length. Subequivalve, ~ . L subequilateral, both rnh-es depressed con-H'X. Beaks small. rising ~lightly aboYe the hinge line. situated at about the mid­length of the shell and a little back of the midlength of the hinge line. Ears sharply separated from the main body of the shell bv narrow sulci: anterior ears a little l~rger than the posterior ones; byssal sinus on anterior ear of right vah-e very shallow. The sulci at the lower margins of the ears diYerge from the beaks at angles of 90 lo 95 degrees on different in­dfriduals. Hinge of left valve, as seen in a l\Iississippi shell. edentulous, but pre­senting a long, narrow, shallow channel bounded by thin erural ridges, parallel to the hinge line. Resilifer triangular, deep, opening inward. Adductor scar large. broadly subovate, situated slightly aboYe the midheight, and a little back of the midlength. Surface of both valves smooth: with a shiny transparent surface glaze which oYerlaps the margins. In­cremental lines verv fine. Dimensions of the left rnh-e shown in plate 20. figure 11: Length 7.9 + mm.• height 7.5 + mm.. co1n-exity about 0.5 mm. The right rnlvc shown in plate 20, figure 10, is B mm. long and 9 nun. high. T_ypes.--The original description cites Eufaula, Alabama. and Tippah County. ·Mississippi, as the known occurrences of the species. The types are probably lost. It is not known from which of the two localities the fi~ured specimen came. Two plesiotypes from Texas, C.S.:\.M. no. 20961. /Jistribution in Texas.-Tador marl: Little Hin~r. below Cummins Bridge, .5% miles ~outh hy we:'t of Bu('kholtz. l\Iilam County (128971 : Salado Cr~ek, 3 ~ ·~ miles t'ast of Alarno H("ight~. Bexar Cuunt\" l. , •' (76·1.9 ·1. Cp~on clay: .-\ ";lank"" ea~t of the rail­ro~d. :3 1 :.! mile~ ~outh of Darlinµ-. l\Ia\·­erick County f 825-!). 1\arnrro group. Nacatoch sand: Vicinity nf Kaufma1\ ll(l]. 2 specimens figured); f:eld :3 5 mile we~t of Kaufman (14103); vicinit\· of Chatfil'ld ~ 7(l2); north edge of Corsic;rna (.SIB) . l\a,·aiTo p:roup. Cor~icana marl: Near Terrell ( 155-l·l) : Onion Creek, 21h miles west of old Garfield (14156) ; 1/2 mile below :Martindale (7621, 15527); Salado Creek, upstream from Highway 90, Bexar County (16671). l\arnrro group, Kemp clay: 2 miles northwest of Deatsville (14128). Ou ts ide distribution .-Arkansas: Naca· loch sand and Arkadelphia clay. Mississippi: Ripley formation, Owl Creek formation. East-central Alabama and Chattahoochee rqrion (Alabama-Georgia) : Bluff town for­mation, Hipley formation (upper part), and Providence sand. The Carolinas: Snow Hill member of Black Creek formation, and Peedee forma­tion (upper part). l\Iardand: l\fatawan formation and Monmouth formation. Dela,rnre: Crosswicks clay, Marshall· town formation, and l\fount Laurel sand. l\ew Jerse~·: Red Bank sand. Range.--In the Coastal Plain the species ranges from the Taylor marl and beds of Taylor age (Exogyra ponderosa zone), upward to the upper part of the Navarro group and beds of Navarro age (Exogyra cost a ta zone). PECTEN (SYNCYCLONEMA ?) ARCHERI Stephenson, n.sp. Pl. 20, fig~. 8, 9 Shell small, thin, suhcircular to broadly subornte in outline, the height in most specimens being ~lightly greater than the length. Only right Yakes are available, and these are subequilateral and only slightly conyex. Beaks small, scarcely ri~ing above the hinge line, situated at ahout the midlenp:th --of the shell. Ears st>parated from the main body of the shell hy well defined sulci, the anterior ear apparently a little larger than the posterior one. Byssal sinus of anterior ear well defined but relati,·ely shallow. Hinge not Invertebrate Fossils of the Navarro Group clearly exposed. Surface ornamented with well defined, round-crested concentric folds, becoming successively more widely spaced away from the beak, separated by wider, broadly concave depressions. The folds become weak toward the dorsal margins. Some shells faintly show a thin depressed line near the crest of each con­centric fold. The better preserved shells exhibit a thin, transparent, surface glaze which slightly overlaps the margins. Dimensions of the holotype: Length 7 mm., height nearly 7.7 mm., convexity scarce!y 1 mm. Dimensions of a larger unfigured shell from near Chatfield: Length 10.8 mm., height 11.2 mm., con­vexity about 1 mm. This species is clearly distinct from Pecten simplicius Conrad, the right valves of which are plain and smooth. P. con­ radi (Whitfield) 182 is a closely related species but compared with the type its con­ centric markings are more sharpIy defined, and are separated by broad, flat-bottomed depressions. The concentrically ribbed right valve of Pecten (Syncyclonerna) halli Gabb (== Pecten rigi.da Hall and Meek) appears to be closely allied to arclieri. Types.-Holotype, U.S.N.M. no. 76438~ 1 paratype, U.S.N .M. no. 20896. Named for the Hon. Branch T. Archer, Commis­ sioner of the Republic of Texas to the United States. Distribution in Texas.-Navarro forma­ tion, Nacatoch sand: North edge of Cor­ sicana (518, type loc.) ; vicinity of Cor­ sicana (763); 4 miles north of Corsicana ( 17366) ; 2% miles west by south of Corsicana ( 17368) ; vicinity of Chatfield (762) ; field south of Chatfield ( 7569) ; % mile east of Chatfield ( 75 71) ; vicinity of Kaufman (761); field 3/5 mile west of Kaufman ( 14103) . Range.-From the N acatoch sand of the Navarro group in Na,'arro and Kaufman counties, Texas; questionably in the Cor­sicana marl of the Navarro group in Caldwell County, Texas. l83Whit6cld, R. P.. U. S. Geel. Survey Mon., vo]. 9, p. 52, pl. 7. figs. s.10, 1885. PECTEN (SYNCYCLONEMA ?) KINGI Stephenson, n.sp. Pl. 20, fig. 7 The description is based on one right valve. Shell small, depressed, thin, subcircular in outline, subequilateral. Beak small, nonprominent. Ears sharply sepa­rated from the main shell by sulci which diverge from the beak at an angle of about 100 degrees. Surface ornamented with numerous small, closely spaced, low, broad-topped, concentric ribs which are formed by thin lamellae attached at the upper edge and folded down closely upon the shell below; the lower edge of each lamella laps up a little onto the next rib below; the ribs are continued upward across the ears where they are narrower and more closely spaced. On the main shell the ribs number 3 or 4 to the millimeter, and on the ears 5 or 6 to the millimeter. The anterior ear is obscurely preserved but apparently the byssal sinus is shallow. Length 11.4 mm., height 11.2 mm. This shell is not apt to be confused with other described species of Pecten. Com­pared with P. archeri it is larger, is longer in proportion to the height, and the concentric ribbing is conspicuously stronger. Holotype.-U.S.N.M. no. 76439. Named in honor of the collector, Philip B. King. Distribution in Texas.-Navarro group, Corsicana marl: Salado Creek, below St. Hedwig road, Bexar County (16669). PECTEN (SYNCYCLONEMA ?) TRAVISANUS Stephenson, n.sp. Pl. 22, figs. I, 2 Shell small, thin, subcircular in outline, depressed convex, the two valves of about equal ventricosity. As in most other species of Pecten the different individ­uals of this species vary slightly in the proportion of length to height; some indi­viduals are approximately equal in length and breadth. Beaks small, flattish, barely projecting above the hinge line; angle of umbonal shoulders about 95 degrees near the beak, the angle increasing some­what distally. Hinge edentulous; a nar­row, rather weak ridge closely parallels The University of Te.t-as Publication No. 4101 the hinge margin; resilifer small, trigo~al. Internal features obscure. hut the surl ace of the internal mold faintly reflects the sculpture of the outer surface. The mar­gin of the main shell is approximately circular; the ears are relatively large; anterior ear of right valve separated from the main shell by a narrow, deep sulcus; byssal sinus shallow. Surface of left valve includinO' the ears, nearly smooth ' b d. but marked by faint, fine, irregular ra i­ating lines, and by very fine growth lines; these vary in strength, some shells appear­ing very. smooth; the surface of the in­ternal mold shows faint, broad, very shal­low, irre~ular, radiating undulations. Surface of right valve ornamented with fine, sharp, concentric lines spaced 2 or 3 to the millimeter; these are much stronger than those on the left valve; fine radiat­ing lines can be detected but are exceed­ingly faint; ears marked only with fine growth lines; broad, exceedingly faint, radiating undulations are also noticeable on this valve. Dimensions of the holotype, a left valve: Length 15. 7 mm., height 15.1 mm., con­vexity about 1 nun. This species is larger and has more surface ornamentation than Pecten simpli­cius Conrad. Pecten parvus ('Whitfield), reported to have come from the Nave­sink marl at Freehold, New Jersey, is a closely related species, but apparently has more pronounced, and more regularly developed radial sculpture of the Campto­nectes type. Types.-Holotype, U.S.N.M. no. 76440; 1 figured paratype. O.S.N.M. no. 76-t.41; 7 unfigured paratypes, U.S.N.M. no. 76442. Distribution in Texas.-Navarro group, Corsicana marl: 24/.3 miles east of Cool­edge (13832) ; 2 miles south of Corsicana (16167) ; 5 miles southwest of Quinlan (15546). Navarro group, Kemp clay: Webber­ ville (760L type loc.; 13910.l; well near old Garfield ( 16-11). PECTEN (SYNCYCLONEMA ?) sp. One internal mold of a small Pecten with a fra~ment of the shell adhering, from the Kemp day on Colorado River at Webberville ( 7601) is about the same size as P. ( Syncrclonema} archeri, but it is not quite so high, the height ~nd length beinrr about equal, and the mterspaces betw~en the concentric ridges appear to he a little wider and there is a well defined line in the bottom of each interspace. U.S.N.M. no. 76-H3. Subgenus NEITHEA Drouetts3 Type species.-Pecten aequicostatus Lamarck (designated by Chenu, Man. Conchyl. Pal., vol. 2, p. 186, figs. 941-944, 1862). PECTEN (NEITHEA) BEXARENSIS Stephenson, n.sp. Pl. 22, figs. 7, 8 Shell of moderate size, subcircular m outline, right valve strongly convex, greatest ventricosity central above the midheight, nearly equilateral, strongly in­equivalve. Dorsal slopes steep, overhang­ing the ears. Beak of right valve promi­nent, strongly incurved, direct, slightly overhanging the beak of the left valve. The hinge line is straight and about 12 mm. long. The species belongs to a group of strongly inequivalve shells in which the right valve exhibits six major ribs with two or more smaller, subequal ribs in the interspaces between the larger ones. In this species there are two intermediate ribs, and the major ribs are only slightly more prominent than the intermediate ones. All the ribs are rather prominent, broadIy rounded over the crests, and are wider than the interspaces. Each of the ribs is further ornamented with 2 to 5 subribs which are low and broadly round­crested; these tend to become obscure and die out toward the beak. The interspaces are rather broadly rounded and are either without subribs or may have one or two very obscure subribs. The space between any two intermediate ribs is a little nar­rower than the spaces on either side of the major ribs. The space between the anterior major rib and the anterior ear presents one central narrow, shall subrib and back of this is a still smaller very ob­scure subrib. The space between the pos· terior major rib and the posterior ear presents 4 subribs and several intermediate 183Drouet, C., !\li-m. Soc . Linnccnne, Paris, vol. 3, P• 186, 1825. Invertebrate Fossils of the Navarro Group very obscure suhribs. The external inter­spaces are reflected on the inner surface of the shell as square-topped internal ribs, nar­rower than the interspaces; the sub ribs are only obscurely reftected internally. The anterior ear is of moderate size and is convex in a sinuous manner outward from the beak; it is separated from the main ahell by a narrow, sinuous groove, and is ornamented with 7 or 8 small, narrow, unequal, radiating ribs. The posterior ear is subequal to the anterior one, and is similarly ornamented, except that on the holotype 4 of the centrally located ribs are so spaced as to form two pairs. The concentric markings consist of fine sharp, somewhat irregularly spaced ridges of sub­microscopic size, numbering 5 to 10 to the millimeter. The left valve is not repre­aented in the type material. Dimensions of the holotype. a right valve: Length 23 mm., height 23.5 mm., convexity about 9 mm. Thia species has its nearest ally in Peden ( N eithea} austinensis (Kniker) , from the Austin chalk at Austin, Texas, but differs mainly in that the two ribs between the major ribs are less closely crowded together; there is also a more ohecure development of subribs in the bottoms of the interspaces. According to the measurements given for the Austin species, P. (Neithea} bexarensis appears to be more convex, and more nearly sub­circular in outline. Typu.-Holotype, U.S.N.M. no. 76444; 2 unfigured paratypes, U.S.N .M. no. 76445. I>Utribution in Texa.!.-Navarro group, Corsicana marl: 14 miles west by south of San Antonio (TeL Bu. 742) ; 6 miles east of Castroville (15502, 16156, and Tex. Bu. 3282, type loc.); ?near Castro­ville ( 7665). Salasenus AMUSJUM BoltenU& Type species.-Pecten pleuronectes Linne. PECTEN (AllUSIUM7) DANEI Stephen.son. n.ap. PL 22, figs. 9, IO Shell small, thin and fragile, subcir­cular to broadly suhovate in outline, some­what inequilateral due to large posterior •Boltea. J. F.. Museum Boltenianum, 1st ed., p. 165, 17'1. (Ed:ted with Mlpplementary nfereace8, b7 Peter t'IWdola Jloedinc.) ear, depressed convex. Beaks small and flattish, nonprominent, not well preserved, situated about midway of the length of the shell. Anterior ear of left valve of mod­erate size, smooth, separated from the body of the shell by a narrow, moderately deep sulcus. Posterior ear of left valve, large, broad, triangular, smooth, not lim .. ited by a sulcus below, but passing upward in a gentle slope into the body of the shell. The hinge is edentulous and over­hangs inwardly along the dorsal margin. The inner surface bears 10 or 12 narrow sharply defined radiating ribs which are loosely attached to the shell and are easily separated from it in the form of rod-like bodies; in the available material these ribs do not bear a definite relationship to the exterior ribs, for some of them occur beneath the interspaces of the exterior, and others beneath the exterior ribs; on the basis of these internal ribs the species is referred questionably to the subgenus Amusium, but the large posterior ear and the strong radiating ribs throw doubt on the correctness of this assignment. Outer surface ornamented with about 12 ir­regularly spaced, narrow, sharply defined radiating ribs which are reflected on the inner surface as radiating depressions; in­cremental lines numerous, sharp, becom­ing fine, overlapping lamellae toward the ventral margin, where they produce closely spaced serrations on the tops of the ribs. The holotype as it originally broke out of its marl matrix revealed only the in­terior of the shell. A photograph of the interior was made (pl. 22, fig. 10) , after which melted wax was pressed into the cavity and an attempt was made to clean the matrix from the exterior; as the shell was fragile and did not completely adhere to the wax, the attempt was only partly successful (pl. 22, fig. 9); however, the ribs are well shown and enough shell fragments remain to reveal the character of the surface ornamentation. Dimensions of the holotype: Length 14 mm., height 12 mm. Types.-Holotype, U.S.N.M. no. 76446; 1 paratype, U.S.N.M. no. 76447; 2 para­types, U.S.N.M. no. 76448. Named in honor of Carle H. Dane, who assisted the The Uufrersity of Te:i:as Publication No. 4101 writer in collPrtino-t"\ fossil::; at this and tither localities in casl-<'<'ntral Texas. Distr£lmtio11 in Texas. Navarro group, Corsicana marl: 2 I.,~ mile~ east of Cooledge (1:1~t12. ] ll 37. t) pe lots) . PECTEN (AMUSIUM) sp. Two poorly preserved specimens of Pee/en (l.1130). found in the Kemp day on San Gabriel River 2 15 mile above the San Gabriel-Thorndale road crossing, Milam Countv. exhibit 6 irregularly spaced, but weil defined internal ribs, and a smooth outer surface; they therefore be­long to the subgenus Amusium. These shells are small, about 10 mm. long, and occur in a phosphatic, strongly glaucon­itic, chalky conglomerate at water level al the base of a bluff; the overlying beds appear to belong to the Kemp clay and the conglomerate is therefore referred to that division. U.S.N.M. no. 76449. Subgenus RADIOPECTEN Stephenson, new subgen. Type species.-Pectcn ( Radiopcctcn} u:eeksi Stephenson, n.sp. Etymology.-Radius, a ray; perten, a comb. The subgenus Ra.diopecten is based on the 'vel1 preserved material from Coon Creek, J\k~airy County, Tennessee, de­scribed by \Vade1 ~:; under the name Pccten quinquenariu.s Conrad (U.S.N.M. no. 32761), and here renamed Pecten (Radiopecten) u·eeksi, in honor of Mr. Dave Weeks, owner of the Coon Creek fossil locality. This species is nearly re­lated to Peeten (Radiopeeten) mississ1'.p­pie11sis (Conrad), from either the Ripley or the Ow1 Creek formation, in Tippah County, l\'l ississippi. The distinguishing characters of the sub- L '---' genus are, the slight co1n-exity of the vah-cs, the irregularity of the ribbing, and the narrow, sharply defined ribs on the left Yah-e. contrasting with the broadly rounded rihs of the right vake. The in­cremental lincs arc fine, sharp, and densely crowded. The left rnh·e is notice­ably more conn~x than the right valve. In outline the shell is broadh-subovate, the length slightly exceeding .the height. lb:'•Wadt', Bru«•'. l ·. ~-Ct·ol. :'11n1·y Prof. Papt·r 137, p. 65, pl. ~I. Ii:;~. 6-Q, 19:26. PECTEN (RADIOPECTEN) MISSISSIPPIENSIS Conrad? Pl. 22, fi~~. 11-13 lB60. Pcctc11 mississippic11sis ( :onrnd, Acud. Nat, Sci. Philadelphia .lour., .:!d ~er., vol. 4, p. 28:~. '? 1885. Pcctcn quinquc11arius Conrad. Whitfield, lJ.S.Geol. Survey Mon., vol. 9, p. 47, pl. 7, figs. 13-16. (Geol. Survey New Jersey, Paleontology, vol. 1, p. 47, pl. 7, figs. 13--16, 1886.) 1905. Pccten mississippiensis Conrad. Johnson, Acad. Nat. Sci. Philadelphia Proc., vol. 57. p. ll. 1907. Pectcn quinqurnaria Conrad. Weller, Geol. Survey New Jersey, Paleontology, vol. 4. p. 476, pl. 50, fig. 13 (questionably figs. 10-12). 1923. Pecten missz'.ssippiensis Conrad. Stephen· son, North Carolina Geol. and Econ. Survey, vol. 5, pt. l, p. 201, pl. 55, figs. 12-15. 1926. Peden <1uinqucnarius Conrad. Wade, U. S.Geol. SurVt'Y Prof. Paper 137, p. 65, pl. 21, fip;~. 6- 9. Shell thin, subequilateral, inequivalve, subcircular to broadly subovate in outline, adults generally a little longer than high, both valves only slightly convex. Beaks small, flattish, barely rising above the hinge line, situated at about the midlength of the shell. Ears moderately large, triangular, subequal, marked only by fine transverse growth lines; the lower bound­ing lines of the ears diverge from the beak at an angle of 100 degrees or more; byssal sinus of right ear well developed, but not profound; a shallow sulcus extends from the byssal notch to the beak. Hinge long, narrow. edentulous with a shallow groove paralleling the upper margin. Resilifer triangular. opening inward, bordered by narrow, diverging crural ridges. The in· ner surface of the shell reflects the ribs and folds of the outer surface. Surface of left valve marked by five broad, low folds each of which supports a prominent, narrow central rib; on the sides of the folds and in the intermediate depressions are smaller, sharp ribs which number 2 to 4, between any two of the larger ribs; of these smaller ribs the ones nearest the major ribs are the larger and this is especially true on the second, third, and fourth folds from the anterior end. Sur· face of right valve marked by unequal, Invertebrate Fossils of the Navarro Gr.oup broad, radiating folds, each fold cor­responding to one of the major d~p~es­sions on the left valve. Sharp rad1atmg ribs are wanting, but on adults each of the ribs of the left valve is reflected as a shallow more or less distinct depression on the outer surface of the right valve. Dimensions of a medium sized left valve from Chatfield: Length 38 mm., height 38 mm., convexity about 3 mm. This species has been referred by sev­eral authors to Pecten quinquenarius Con­rad, from the Upper Cretaceous exposed on the Chesapeake and Delaware Canal. The latter is based on an internal mold of an obviously related form, which is specifically indeterminable, but which ap­pears to be much more strongly plicated. Types.-Two rather small specimens, one a left and the other a right valve, in the collection of the Academy of Natural Sciences of Philadelphia, from Tippah County, Mississippi, probably from the Owl Creek formation on Owl Creek 2~~ llliles northeast of Ripley. Two plesio­types, left valves, from Texas, U.S.N.M. no. 76450; 1 plesiotype from Texas, U.S.N.M. no. 76451. Distribution in Texas.-Taylor marl: ?Gully south of the Clear Springs road, 4 miles southeast of New Braunfels, Guadalupe County (7626). San Miguel formation: ?Westward-fac­ ing slope east of the railroad, l 1h miles northeast of Paloma, Maverick County (8253); ?Del Rio road, 121h miles north­ west of Eagle Pass, Maverick County (1513); ?Uvalde road, 12% miles north­ east of Eagle Pass, Maverick County (8257). Navarro group, Neylandville marl: 3~4 miles w e s t -n o r t h w e s t of Corsicana (16166). Navarro group, Nacatoch sand: Vicin­ity of Kaufman (761, loc. of 2 plesio­types) ; road 3/5 mile west of Kaufman · (12923; 14098, loc. of 1 plesiotype); vicinity of Chatfield (762) ; 21h miles north of Corsicana (14114): Outside distribution.-Arkansas: N aca­ toch sand. Mississippi: Ripley formation and Prairie Bluff chalk. North Carolina: Peedee formation (up­per part). Range.-The species ranges question­ably from the upper part of the Taylor marl, and beds of upper Taylor age (up­per part of Exogyra ponderosa zone), up­ward through the N acatoch sand of the Navarro group, and through beds of cor· responding age (Exogyra costat,a zone) elsewhere in the Coastal Plain. Family SPONDYLIDAE Genus SPONDYLUS Linne SPONDYLUS MUNITUS Stephenson, n.sp. Pl. 24, figs. 8, 9 Shell of moderate size, subovate in out­line, strongly convex, subequilateral, strongly inequivalve. The two valves dif­fer markedly in form and sculpture. The left valve is depressed convex; shell de­stroyed except the ears, and parts of the dorsal slopes; it is thin about the beak, and thickens toward the margins; the por­tion of shell remaining on the postero­dorsal slope exhibits 7 low ribs of some­what irregular trend, narrower than the interspaces and supporting a few scat­tered low, blunt spines; the posterior ear is of moderate size and is marked by 3 or 4 very obscure ribs, and along its lower margin is a row of 6 very unequal closely spaced spines; the 3 outer spines are partly broken away, but are strong and prominent, while the 3 inner ones are smaller and, though broken, are probably shorter; the anterior ear is slightly smaller and is wanting in radial ribs; one low strong rib on the upper border of the main shell surface, borders the lower mar­gin of this ear; impressions on the in­ternal mold indicate that the left valve is completely ornamented with numerous, radiating ribs of unequal size and spacing, the ribs in general being narrower than the interspaces; the mold also exhibits numer­ous, fine radiating lines between and on the rib impressions; the beak is small, incurved, direct, and projects only slightly above the hinge line. About the posterior half of the right valve is preserved and exhibits a series of prominent, wall-like, concentric ridges rising near I y at right The Unfrersity of Texas Publication No. 4101 angle~ to the ~urfa<'P, or tilkd slightly up­ward, averaµ:i ng about 1 mi Iii meter in thickne:'.'~ and spaced somewhat i rreguIarl y hut reaching a maximum of 8 mm. apart toward the outer margin: all these ridg:es are more or less broken a\·ray, but one can be seen to rise fully 5 mm. above the surface: the surface of the shell be­t ween the concentric ridges is marked by low, obscure radiating ribs, 11 or 12 to the centimeter, wider than the shallow interspaces, and the whole surface ex­hibits fine radiating lines; both ribs and lines are reflected on the internal mold; the beak is strong!y incurved and strongIy prominent; its tip is obscured by the at­tachment of the shell over a large area to one or more irregular shell fragments; the ears are small and are ornamented only with growth lines. The hinge is straight and about 14 mm. long. With the exception of the rib markings on the in­ternal mold, the internal features are not observable. Dimensions of the holotype: Right valve, length 23 mm., height 32 mm., thickness about 22.5 mm.; left valve, length 22 mm., height 26. 7 mm., convexity about 4.5 mm. The only American Upper Cretaceous species at all like this one is S pondylus gregalis (Morton), from the Navesink marl, New Jersey. It is a larger, more elongated and less ventricose species, and has flatter, more irregular, concentric laminae. Holot_ype.--l.':.S.l\.r..L no. 76452. Distribution in Texas.-Navarro <>TOU}l L' ' Corsicana marl: 1 3/10 miles north of McQueeney ( 1552-1.) . SPONDYLUS sp. The inner surface of a right valve of an indeterminate species of Spondylus, the entire outer surface of which is attached to a shell of Gryphaea, was found in the Corsicana marl on Mesquite Creek, 4 miles north of Castroville, Medina County (Tex. Bu. 7-171. The inner surface re­flects numerous unequal ribs of unequal but rather close spacing. Genus PLICATULA Lamarck PLICATULA MULLICAENSIS Weller Pl. 22. figs. H. 15 1907. Plicatula mullirncnsis W t'ller, Ceol. Survey New Jersey. Paleontology, vol. 4, p. 485, pl. 52, figs. 3-5. 1926. Plicatula urticosa 1\lorton. Stephenson, Geol. Survey Alabama Special Rept. no. 14, p. 248, pl. 91, fig. 3. Shell thin, subcircular to broadly subovate in outline, the height generally greater than the length, depressed convex. Hinge not seen well preserved in the Texas material. As seen in molds from Alabama the resilifer lies between two crural ridges which diverge slightly from above down· ward. A large subcircular adductor muscle scar is situated a little above the mid-height, and a little back of the mid­ length. Surface ornamented with numerous, closely spaced, irregularly arranged, ill­defined, radiating ribs ·which are set with numerous slender spines formed by tightly rolled upfolds of the growth lamellae; these folds project obliquely downward and outward, and may attain as much as 3.5 or 4 mm. in length. The spines on the right valve are coarser and somewhat more irregularly distributed than those on the left valve; as seen in a large suite of specimens from Alabama, there is considerable individual variation in the coarseness of the ornamentation. Dimensions of the shell with both valves shown in plate 22, figures 14, 15: Length 22 mm., height 24 mm., thickness 6.5 mm. The largest shells attain a length of 35 mm. The Texas material has been compared with the type of Weller's species, Plicatula mullicaensis, from the stratigraphically lower Navesink marl of N cw Jersey and the ornamentation on the Texas specimens appears to be essentially identical. The ornamentation on P. urticosa Morton from ' New Jersey, is coarser, though Morton's Alabama specimens may have been the same as 'Veller's species.· Types.-,Veller's figured cotypes are in the. Walke~ 1'\fos~um at the University of C_h1ca~o, U.C. 10631; they are from the Navesmk marl at Mullica Hill Gloucester ' County, New Jersey; in the same museum Invertebrate Fossils of the Navarro Group are topotypes, U.C. 18630. Plesiotype from Texas, U.S.N.M. no. 76453. Distribution in Texas.-Navarro group, Corsicana marl: 2 miles east of Marion (Tex. Bu. 2395); near Castroville (7665, 7796) ; 4 or 5 miles north by west of Castroville (10627, Tex. Bu. 747) ; 2 miles south of Clifl (10870, 1 specimen figured) ; well 7/20 mile south by west 0£ SL Mary's University, Bexar County (16353, 16408) ; arroyo 2/5 mile south by west of St. Mary's University, Bexar County (16354, Tex. Bu. 744); well on G. A. Harper Survey, Medina County, at depth of 1045 feet (13844). Out&ide distribution. -Mississippi : Prairie Bluff chalk. Alabwna: Prairie Bluff chalk. New Jersey: Navesink marl. PUCATULA TETRICA Conrad? Pl. 22, fig. 16 1860. Plica!ula tetrica Conrad, Acad. Nat. Sci. Philadelphia Jour., vol. 4, 2d ser., p. 283, pl. 46, fig. 26. 1905. Plicatu/.a tetri.ca Conrad. Johnson Acad. Nat. Sci. Philadelphia Proc., vol: 57 p 12. ' • • Shell extremely irregular in form but m general subovate in outline, highert!1an long, attached valve generally flat­tish, free valve flattish to moderately convex. None of the specimens is perfect enough for accurate measurement hut one is 36 mm. high, and a small ' attached valve is 15 mm. long and 18 mm. high. · Hinge not well preserved. Inner surface smooth or faintly reflecting the exterior ribs. Surface of free valve ornamented with 10 or 12 prominent, extremely irreg­ular, radiating ribs, set with numerous irregularly distributed, low to prominen; spines which are formed by sharp unfolds of prominent growth Iamellae· some of the spines are as much as 5 ~. high; on some specimens finer ribs may appear between the larger ones, and these may . become large and prominent as they pass toward the ventral margin. The ribs on the unattached part of the lower valve appear to be smaller, more numerous and 10mewhat more regular than those on the upper valve; they are also spinose. Both the ribs and spines exhibit great varia­bility on different individuals. Compared with the type this specimen is more finely and more elaborately sculp­tured. PlicoJ,ula clarki Stephenson from the Snow Hill member of the Black Creek formation of North Carolina is a similar, though more regularly ornamented species. Types.-Holotype, Academy of Natural Sciences of Philadelphia; from Tippah County, Mississippi. One questionable plesiotype from Texas, U.S.N.M. no. 76454. Distribution in Texas.-Navarro group, Corsicana marl: 2% miles north by east of Malta ( 12933, 1 specimen figured) ; 114 miles south by east of Oak Grove (16160); 2 miles south of Oak Grove ( 12932) ; 21h miles west of McQueeney (15523); ?fuller's earth pit 14 miles west of San Antonio ( 15520) ; well on G. A. Harper Survey, Medina County, at depth of 1045 feet (13844). Outside distribution.-Arkansas: Ques­tionably in the N acatoch sand. Mississippi: From "Tippah County," from the Ripley formation or the Owl Creek formation. Range.--Corsicana marl of the Navarro group in Texas; Nacatoch sand in Arkan­sas; questionably the Ripley and Owl Creek formations in Mississippi. Unidentified specimens of PLICATULA Two indeterminate imprints of Plicatula were found in the Corsicana marl on Medina River at the lower crossing at Castroville, Medina County (7796) . U.S.N.M. no. 76455. A print of a small, poorly preserved, ribbed PlicoJ,ula was found in a gray calcareous clay matrix near Webberville, Travis County (1642); from its geo­graphic position it presumably came from the Kemp clay of the Navarro group. U.S.N.M. no. 76456. The phosphatic mold of the exterior of a Plicat,ula, found by Mr. and Mrs. D. A. Saunders of Greenville, about 50 yards northeast of the Lone Oak pike, on the east side of Cowleach Fork of Sabine River, about 12 miles southeast of Green­ville, Hunt County (11247), is orna­mented with fine spines resembling those of P. mullicaensis Weller. (Pl. 22, fig. 17.) The Unirersity of Te.ms Publication No. 4101 The spines. howeYer, arc set on more defi­nitely den•loped radiating ribs, and the mold may represent a varietal form. The containing bed is a phosphatic conglom­erate at the base of the Eocene (l\1Iidway group). in which fossils from the under­lying Kemp clay are present as a mechani­cal mixture. U.S.~.M. no. 76-157. Family LL\110_\E Genus LIMA Bruguie1·e,1''' sensu lato Type ~pt>cie:-'.-Ostrca lima Linne. a Recent ~pecie:-' from the .\lt·diterranean. LIMA SELLARDS! Stephenson, n.sp. Pl. :2-1. fi~~-10. 11 Shell subornte in outline, oblique, equi­vah-e, inequilateral, moderately convex. Beaks moderately prominent~ strongly in­curwd, direct, situated somewhat in adYance of the midlength. Ears small, the posterior one a little larger than the anterior one. both nnvin~ upward into the dorsal slopes without sharp delineation. Dorsal slopes steep, the posterior one the steeper. Hinge line nearly straight and about 6 mm. long in the holotype. An­terior margin slightly sinuous near its junction with the hinge line, becoming broadly rounded below, fullest above the midheight, passing broadly and regularly into the wntral margin; the lower pos­terior margin is more sharply rounded than the wntral and passes upward into a long forward sloping posterodorsal margin which is slightly convex, and becomes a little sinuous as it meets the hinge line. Dorsal margin slightly arched. Surface ornamented with 20 to 24 mod­erately prominent ribs~ of which the ones on the dorsal slopes become progressively weaker toward the ears; the ears are nearly smooth: the ribs are a little wider than the broadly V-shaped interspaces, in the bottom of each of which is a small. fairly distinct subrib; the main ribs are smooth and round-crested from the beak well down on·r the shell, but as they approach the margin they become more sharp-crt=>sted and bear small tuber­r les; the subribs are smooth near the beak, 1~0u~u:.:ui;·r··· J.. T.1h:. Encvt·I. \!,··th. \"1·r,-. C.t•q . •·tc .. \"ol. 2. 111. :.:nti. 1:-0:-. ~•.•• :il~ti ~'"''·art. H. n...\caJ. :\at. Sci. Philad•·l phiJ ~per . Pub. '.\.i. 3. p. l:.: L l 1> 30. but as they pass downward they exh~bit first fa int. then distinct. tubercles which are smaller and closer together, but more distinct. than those on the main ribs. The fine growth lines ~)ecome a little stronger toward the margins. Dimensions of the holotype, a left valve: Length 14 mm., height 15 mm., convexity about 4 mm. A paratype, a right valve, on matrix near the holotype, is 14.4 mm. high. This species belongs to a subgroup of the genus Lima of which L. oxypleura (Conrad), L. pelagica (Morton), and L. pelagica covensis Stephenson,187 are closely related members. L. geronimoen· sis also exhibits a similar though very much coarser type of ribbing. L. sellardsi agrees most closely in the number of its ribs. with L. oxypleura, from the Snow Hill member of the Black Creek forma· ti on of North Carolina, but the latter attains a larger size and has sharper· crested ribs on which the serrations begin to appear at a lesser distance from the beak. Types.-Holotype, U.S.N.M. no. 76458; 1 figured paratype. U.S.N.M. no. 76459; 6 selected unfigured paratypes, U.S.N.M. no. 76460. Distribution £n Texas.-Navarro group, Kemp clay: 2Va miles west-southwest of Staples (10878, type loc.) ; near Deats· Yille (764, 14125). LIMA PELAGICA WOOLSEY! Stephenson, n.var. Pl. 23, fi~~. 5, 6 This ,-arietal form is closely related to Lima pelap:ica covensis Steph~nson,iss but differs in haYing smoother dorsal slopes m1d more weakly deYeloped subribs be­tween the main ribs. The holotype is ornamented with 35 ribs which are \ --shape in cross section and are faintly [!nd finely tubereulated, especially toward their distal ends: the tubercles are not "elI presern·d in the holotype but may hC' more clearly seen on the paratype shown in plate 23, figure 6. At the bot· tom of each interspace between the main 1~7~:ephenson. L. YC. :\orth Carolina Geol. and Econ. Sun.·y. Yol. 5. pt. l , pp. 210-21:.!. pl. .'-8, figs. 1·3 and 16-18. lQ~J. 1~"~tep!1en~on. L. W .. op. cit., p. 211. ribs is a faint raised line or subrib which is minutely tuberculated. The ribs on the posterodorsal slope become very weak and practically fade out before the dorsal margin is reached; almost the lower half of the anterodorsal slope is smooth except for the fine, sharp growth lines. Dimensions of the holotype, a right valve: Length 13 mm., height 15.8 mm., convexity about 5 mm. Types.-Holotype, U.S.N.M. no. 76461; 1 figured paratype, U.S.N.M. no. 76462. Distribution in Texas.-Navarro group, Corsicana marl: % mile below Martin­dale ( 7621, 15526, type lots; 15527) ; 1 3/10 miles north of McQueeney (15524). LIMA DEATSVILLENSIS Stephenson, n.sp. Pl. 23, figs. 7, 8 Shell of moderate size, subovate in out­line, oblique, inequilateral, moderately convex. Beak prominent, strongly in­curved, direct, situated considerably in advance of the midlength. Ears relatively small, the posterior one the larger, not sharply delimited hut curving upward into the steep dorsal slopes. The umbonal ridge is hroadl y rounded and extends from the beak to the lower posterior extremity. Hinge line straight, about 11 mm. long in the holotype. Interior of shell not uncovered. D o r s a l margin slight!y arched; anterior margin a little sinuous near its junction with the hinge line, broadly rounded below, fullest above the midheight, passing in a broad curve into the ventral margin; the latter is rather sharply rounded as it curves around into the posterior margin which is fullest above the midheight; posterodorsal margin long and a little convex, becoming slightly sinuous as it passes up to the hinge line. The surface is alm~st completely covered with radiating ribs which, including small and large ones, number 23 or 24. Ten or 12 of the main ribs are broadly round­crested, and are separated by wider, broadly concave interspaces; each of these larger ribs as it leaves the beak is prom­inent, squarish in cross section, and smooth, but as it passes downward the crest rounds off, faint subribs appear, and these become more distinct downward; on the fully developed major ribs the subribs number 3 to 5 and are rather evenly distributed over the crests and down over the sides. Subribs appear in the inters paces also; they number 1 or 2 in the interspaces on the umbonal ridge, but increase to 3 or 4 from the umbonal ridge forward. The ribs become succes­sively more simple down over the dorsal slopes, and the few small ribs on the ears are undivided. The wrface is further marked by numerous small, closely spaced, sharp, concentric laminae which are produced into small tubercles where they intersect the subribs and the smaller un­divided ribs, thus giving to the surface a finely lined and granulated appearance. Dimensions of the holotype, an incom­plete left valve: Length 22 + mm., height 25 mm., convexity 8 mm. The ribs on this species are broader, more rounded and much more completely broken up into subrib~ than are the ribs on Lima geronimoensis. Lima squarosa ( Gabb) ( = Ctenoides squarosa Gabb) from "Alabama" is a related species, but the major ribs are fewer and coarser and the minor ribs on the larger ribs are very weak. Types.-Holotype, U.S.N.M. no. 7frt63; l figured paratype, U.S.N.M. no. 76464. Distribution in Texas.-Navarro group, Corsicana marl: 1 3/10 miles north of McQueeney (7637, loc. of paratype) ; 21h miles west of McQueeney (15523). Navarro group, Kemp clay: Near Deatsville ( 764, loc. of holotype) ; 3 miles northwest of Lockhart (Tex. Bu. 1174). LIMA COKEi Stephenson, n.sp. Pl. 24, figs. 12, 13 This species resembles L. deatsvillensis in form and type of sculpture, but is more simply ribbed. The concentric ornamenta­tion is finely laminar, closely spaced, and sharply defined; there is one fine, sharp subrib running down the crest of each larger rib, and on some ribs of some speci­mens the rudimentary beginning of a subrib on one or both sides of a major rib is indicated by indistinct rows of nodes on the concentric laminae. One subrib The Unitersity of TeJ.·as Publication No. 4101 onh appears in each intt>rspace. Small. more or lt>ss distinct nodes appear on the subribs where theY are crossed bY the . . concentric laminae. The dimensions of the holotype. a medium-sized right rnh-e. are: Length. about 12 mm.. height 1-l mm.. conYexity about 5 mm. The largest spe2imen in the collection. a rid1t Yah-e is about 20 mm. long and 22 n~m. high. Type.-Holotype. FS.:\.\I. no. 76-t.65: 2 figured paratypes. r .S.:\.:\I. no. 76-t66. 5 unfigured paratypes. C.S.:\.\I. no. 76-167. :\amed for the Hon. Richard Coke. GoYernor of Texas. 187-l to 1877. Distribution in Texas.--'\"aYarro group. Corsicana marl: 21 ~ miles west of :\k­Queeney (_15523) . LIMA GERONIMOENSIS Stephenson, n.sp. Pl. 23. fig. 11 Shell of modera~e sizP. subornte in out­line. oblique. inequilateral. moderately conwx. The distinguishing characters of the species lie in the surf~ce ornamenta­tion which consists of about 25 ribs, count­ing those of both small and large size. All except a few of the ribs on the lower dorsal slopes and ears are prominent and subsquarish in cross section. and are sepa­rated by deep squarish interspaces a little narrower than the ribs. The ribs continue smooth and subsquarish well down owr the shell. but toward the ,·entral margin tC'nd to sharpen up on the crests and to become finely tuberculated: these features begin farther up on the ribs on the umbonal ridge and on the posterodorsal slope. than they do on the rest of the shell. In the bottom of earh interspace is a fine riblet which may be:c-me fineh· tuberculated as it passes to.ward the Yentra·l margin: some of the wider interspaces ex­hibit I or 2 still fi:1er additional riblets toward the Yentral margin. Dimensions of the holotype. a left rnh-e whost> form and outlinf' han~ been some­ what distorted hY the oxidation of the ferruginous matrix: Lenµ-th 22 -mm.. hei~ht 22 mm.. cc nYexity 71 "? 1 mm. This spe~·ies exhibits a simpler type of ornamentation than that on Lima deats­n.llcnsis: the ribs stand up more prom- inenth-and are more squarish than on that speci~~. The ribbin~ is similar to that of L. sellardsi except that it is very much coarser. Holotype.--r.S."\.\I. no. 76468. Distribution in Te.rns.--:\a,·arro group, Corsicana marl: 2 miles south of Cliff f 10870. type loc.) : 6 miles east of Cas· trO\·ille t 15502). LIMA GUADALUPENSIS Stephenson, n.sp. Pl. 23, figs. 9, 10 This shell is similar in form and outline to L. deatsi-illensis. The ribbing is similar to that on L. geronimoensis except that the ornamentation is less simple. The ribs number about 2-t; on the main part of the shell they are prominent, subsquarish, and slightly narrower than the interspaces; they are simple from the beak to a point about halfway to the ventral margin where~ on 6 or 8 of the central more prominent ribs, 1 or 2 obscure, fine sub­ribs appear near the crest, and these be­come somewhat more distinct toward the margin: on some shells 3 subribs are present on the upper part of these major ribs near the shell margin: subribs are not distinguishable on the larger ribs on the anterior and posterior slopes. One or two fine subribs appear in the bottoms of the interspaces between the larger ribs on the main part of the shelL and these subribs extend more than halfway to the beak; they become fainter both toward the front and rear and are wanting between the ribs on the dorsal slopes. The fine concentric bminae are much weaker than on L. deats­ril!ensis~ but they produce small, distinct nodes where they cross the intercostal subribs. and much weaker nodes where they cross the costal subribs. Types. -H o l o t y p e, a left valve, r.S.~.~I. no. 76-1-69: 1 figured paratype, LS.~.:'.\I. no. 76-170: 3 unfigured para· typ~. C.S."\.:\l. no. 76-171. Di~tribu tion in Tcxas.--l\avarro group, Corsicana marl: 1 3 10 miles north of :\kQueene~· I 7637. 15.52.:1. type lots). :\a,-arro group. Kemp clay: ?from near DeatsYille l :-6-l l . Invertebrate Fossils of the Navarro Group LIMA? ACUTILINEAT.A TEXANA Stephenson, n.var. Pl. 23, figs. 1, 2 Shell thin, subovate, elongate, very oblique, equivalve, very inequilateral, moderately convex. Beaks small, incurved direct, scarcely projecting above the hinge line, situated about the middle of the hinge line, and about ~4 the length of the shell from the anterior extremity. A broad, very shallow depression extends from the beak 8lmost directly downward to the anteroventral margin. Anterior ears small and bent inward almost at right angles to the plane separating the valv;s; posterior ears small, not sharply delim­ited, the surface curving upward into the steep dorsal slopes. A well defined byssal opening produces a sharply defined notch in the anterodorsal margin of each valve just below the end of the hinge. Hinge not clearlv uncovered, length 6 or 7 mm. in adult~. Anterior margin rather broadly rounded above, passing down­ward into a long, very broadly convex ventral margin; posteriorly the ventral margin becomes less broadly rounded and passes upward into a rather sharply rounded posterior extremity; postero­dorsal margin long, strong! y inclined for­ward, s tr a i g h t or slight! y concave anteriorly, curving upward at the end to meet the hinge line. Surface incom­pletely ornamented with fine, acute, radiat­ing, faintly tuberculated ribs of unequal strength and spacing on the different parts of the shell; on the posterior, most in­flated part the ribs are most widely spaced, their maximum separation along the ventral margin being 1 to 1.5 mm. on large individuals; on the depressed area below the beak, the ribs are practically wanting, though exceeding Iy fine, closely spaced, radiating lines can be detected; in front of this nearly smooth area the ribs are fine, distinct, closely spaced on the type, but more widely spaced on some other individuals; the interspaces between the main ribs on the posterior part of the shell are broadly concave and nearly smooth, though very faint, closely spaced radial interlining can be detected on some specimens. The posterodorsal slope lacks radiating ribs. The radiating sculpture is somewhat variable on different individuals. The shell is further marked by fine, sharp, concentric growth lines, which have a pronounced development on the ribless posterodorsal slope. The ribs are re­flected on the interior of the shell as radiat­ing depressions. Approximate dimensions of the holo­type, a rather small right valve: Length 17.3 mm., height 15 mm., convexity about 3.5 mm. Large individuals attain a length and height of 25 mm. or more. This variety is essentially like the typi­cal L.? acutilineata (Conrad) , except that the radiating sculpture is much less stron(Ylv developed, and this difference holdsb for all the specimens examined. The species differs much from typical Lima and should perhaps be separated from it. Types.-Holotype, U.S.N.M. no. 76472: 1 figured paratype, U.S.N.M. no. 76473. Distribution in Texas.-Navarro group, Corsicana marl: ~·1 mile below Martin­dale ( 7621) ; I 3/10 miles north of Mc­Queeney (7637; 15524, holotype); 2 miles east of Marion (Tex. Bu. 2395) ; 14 miles west of San Antonio (Tex. Bu. 743) ; near Castroville (76~5, 1 figured paratype; 7796) ; 6 miles east of Castro­ville (15502 16156) ; 4~ or 5 miles north ' ' by west of Castroville (Tex. Bu. 747). Navarro group, Kemp clay: Near Deats­ville (764) ; 3 miles northwest of Lock­hart (Tex. Bu. 1173). LIMA KIMBROENSIS Stephenson, n.sp. Pl. 23, figs. 3, 4 The holotype is a left valve which is imperfect! y preserved in the umbonal por­tion, and along the anterior and ventral margins. Shell of moderate size, sub­ovate in outline, inequilateral, somewhat oblique, and moderately ventricose. Um­bonal ridge broadly rounded. The beaks, hinge, and internal features cannot be observed, and the margins are imperfect. The surface is ornamented with at least 30 radiating ribs; these are strongest on the central and umbonal portions, and become weaker on the dorsal slopes, though they are distinct almost to the The University of Te.ras Publication No. 4101 upper margins; the interspaces are V-shaped and on the main surface there is a distinct line on the bottom of each interspace; the ribs are all more or less distinctly, though finely, tuberculated; those on the anterior portion of the shell are round crested, and the tubercles are blunt and elongated a little in the direc­tion of the growth lines: the ribs on the umbonal inflation are rather sharp-crested and V-shaped in cross section and the tubercles are finer and more pointed; on the posterodorsal slope the ribs and tuber­cles become duller and more like those on the anterior part of the shell. Approximate dimensions: Length 8 mm.. height 9 mm., convexity 2.5 mm.; one fragment questionably ref erred to this species pertains to a shell more than twice as large as the holotype. This shell has the form of Lima pela­gica 1molseyi Stephenson, but the concen­tric markings are sharper and more pro­nounced, the ribs are more strongly de­veloped on the dorsal slopes, and the tubercles on the dorsal slopes are much more strongly developed. Types.-Holotype, U.S.N.M. no. 76474; 1 figured paratype, U.S.N.M. no. 76475. Distribution in Texas.-Navarro group, Corsicana marl: %.~ mile west of Kimbro (l~U29, type loc.); 114 miles south by east of Oak Grove (16160); ?6 miles east of Castroville (15502). LIMA? SAYREI Stephenson, n.sp. Pl. 23, figs. 12. 13 Shell n~ry large. subovate m outline, oblique, inequilateral, equivalve, de­pre~sed com·ex: shell wall thin, greatest inflation below the beaks well above the midheight. from which place the surface rounds off very gently to the anterior, ventral and posterior margins. Beaks and ears not preserved except that a small portion of one ear, the right anterior, rt>mains. Internal features not uncovered. Anterior margin broadly rounded; ven­tral margin more sharply rounded than the anterior margin: posterior margin rather sharply rounded well below the mid­lwight: postcrodorsal m a r g i n Jong, broad!~-conca,·e. The surface is orna­mented with about 38 narrow, low, but sharply distinct, round-crested, radiating ribs, separated by nearly flat-bottomed interspaces which are somewhat variable in wily convex in form. most strongly inflated anteriorh·. hecoming somewhat compressd poste.riorly. BeLaks small, pointed. projecting slightly above the dorsal margin. opisthogyrate. situated somewhat back of the midlength. In gen­eral the anterior margin is regularly rounded. the ventral margin broadly rounded. and the posterior margin rather sharply rounded at about the midheight; in typical specimens the posterodorsal margin is truncated to slightly concave. Hinge edentulous and developed only in front of the beak: it is 10 to 15 mm. long. I to 3 mm. broad. and roughlv striated with concentric g~owth lin~s. · Resilifer submerged within L the margin. deeply im­pressed. flaring inwardly~ and marked on the sides with fine striae. The scar of the anterior retractor muscle is small and is situated just below the forward end of tlw resilifer. and centralh-well above the midheight the byssal. p~sterior retractor and adductor scars are closeh· crowded together. apparently forming -one large, irregular scar~ as the material is pre­sern·d. Surface marked with fine concen­tric growth lines which in some specimens develop into fine owrlapping lamellae; some shells are marked lw irrecrularl)7 . e spaced. shallow growth undulations: rare specimens exhibit fine. rather obscure radiating lines. but these were not ob­sern·d on any of tlw Texas slwlk Dimensions of a large shell: Lencrth 36.5 mm .. height 30 mm .. conwxity ab~ut Hmm. The following characters separate this s1wcies from .-lnomia argentaria Morton: The surface is as a rule wanting in radi­ating lines. but when present they are rela­tiwh· wrv weak: the hinge is limited to that . part. of the dorsal 1;rnrgin in front of the beak: the beak is marcrinal more I::' ' pointed and projects a little; the postero­dorsal margin is generally either nearly straight or a little concave; and the thre~ larf!"er musrle srars are closeh· crowded :-.imulatin£!" one lar£!"e irreaular ~car. '-~ '--I:'" ~ Wade189 The shell described by as A110111 in tcllinoides :Morton, is a slightly distorted left Yake of A. argentaria Morton. Types.-Holotype, collection of the Academy of Natural Sciences of Phila· delphia: From "New Jersey." Although inadequately labeled, it seems likely that the holotype came from the Mount Laurel sand. the lowest formation of the Mon­mouth group. Two plesiotypes from Texas, l~.S.l\.l\l nos. 76486, 76487. Distributz~on in Texas.-Navarro group, l\edandville marl: 7 1/10 miles north­east of Cooper (14083) ; 1h mile north of Cooper (14062) ; 2 miles southwest of Cooper (7511, 1 specimen figured); 8 miles southwest of Greenville (11251, 1 specimen figured; 17382) ; 21/2 miles northeast of Royce Citv (13834) ; 1 mile east of Gastoni~ (7550) ; 3 miles north­east of Drane (16164); 2 7/10 miles northwest of Cooledge (16169). Outside d1~stribut£on. -Mississippi: Selma chalk (in Exogyra cancellata zone). Tennessee: Selma chalk (in Exogyra cancel! ala zone). Central and west-central Alabama: Ripley formation (in Exogyra cancellata zone 'l ; Selma chalk (in Exogyra cancel· !ala zone). East-central Alabama and Chattahoochee region (Alabama-Georgia) : Lower part of Ripley formation (Exogyra cctncellata zone). l\'orth Carolina: Lower part of Peedee formation (Exogyra cancellata zone). Delaware: Mount Laurel sand. l\ew Jersey: Common in the Mount Laurel sand.. Range.-The species is known only from the Exogyra cancellata zone (lower part of Exogyra cos tat a zone), throughout the Coastal Plain from New Jersey to Texas. In Texas the species is recorded from 8 localities in the Neylandville marl. ANOMIA ARGENTARIA Morton Pl. 2-t figs. 1-4 1833. Anomia argcntaria Morton, Am. Jour. Sci., ht ~er.. Yol. ~.'). p. 293, pl. 5, fig. 10. 1834. Anomia argentaria Mo: ton. Synopsis of the oqrnni<' remains of the Cretaceous group of the Cnited States, p. 61, pl. 5, fig. 10. L'-~Wad<'. Rruc<'. t-. S. Geol. Surv<'y Prof. Paper 137, P• 69. pl. ~3. fi~~. 3, 4, 19~6. Invertebrate Fossils of the Navarro Group 1858. Anomia sellaeformis Conrad, Acad. Nat. Sci. Philadelphia J our., 2d ser., vol. 3, p. 330, pl. 34, fig. 6. 1876. Anomia argentaria Morton. Gabb, Acad. Nat. Sci. Philadelphia Proc., vol. 28, p. 319. 1885. Anomia argentaria Morton. Whitfield, U. S.Geol. Survey :Mon., vol. 9, p. 42, pl. 4, figs. 10, 11 (not fig. 9, which is Ostrea plumosa Morton). (Geol. Survey New Jersey, Paleontology, vol. 1, p. 42, pl. 4, figs. 10, 11, 1886.) 1885. Diploschiza cretacea Conrad. Whitfield, U.S.Geol. Survey l\fon., vol. 9, p. 43, pl. 4, figs. 4, 5 (not figs. 6-8) . (Geol. Survey New Jersey, Paleontology, vol. 1, p. 43, pl. 4, figs. 4, 5, 1886.) 1905. Anomia argentaria Morton. Johnson, Acad. Nat. Sci. Philadelphia Proc., vol. 57, p. 12. ?1906. Anomia argentaria Morton. Bose, Bol. Inst. Geol. Mexico, No. 24, p. 38, pl. 1, fig. 8. 1907. Anomia argentaria Morton. Weller, Geol. Survey New Jersey, Paleontology, vol. 4, p. 496, pl. 54, figs. 12-14 (not fig. 15, which is A. tellinoides Morton). 1916. Anomia argentaria Morton. Gardner, l\faryland Geol. Survey, Upper Creta· ceous (2 vols.), p. 608, pl. 35, figs. l, 2. 1923. Anomia argentaria Morton. Stephenson, North Carolina Geol. and Econ. Survey, vol. 5, pt. I, p. 226, pl. 60, figs. 10-14. 1926. Anomia argentaria Morton. Wade, U.S. Geol. Survey Prof. Paper 137, p. 68, pl. 22, figs. 10-13. 1926. Anomia tellinoides Mo:-ton. Wade, U.S. Geol. Survey Prof. Paper 137, p. 69, pl. 23, figs. 3, 4. 1926. Anomia argentaria l\forton. Stephenson, Geol. Survey Alabama Special Rept. no. 14, p. 250, pl. 92, fig. 10. (Figures only.) 1929. Anomia argentaria Morton. Dane, Arkan­sas Geol. Survey Bull. l, pt. 27 (op. p. 150), figs. 7, 8. (Figures only.) The following description pertains to left valves only: Shell thin to moderately thick, inequivalve, typically subequilateral, more or less irregular in outline in dif­ferent individuals but in general sub­circular to broadly subelliptical; varies in ventricosity from concave to strongly convex. Beak small, depressed to slightly prominent, situated centrally and gen­erally I to 2 mm. back from the margin. Hinge edentulous and about equally de­veloped in front and behind the beak, ex­cept as modified on many individuals by crowding; s t r i a t e 7. 7363.S. Two plesio­t y p~ from Texas. LS.:\.\1. no. 76-1-91. Distribution in Texas.---\3yarro group, Corsicana marl: ] ;) l 0 miles north of ]\frQuf"e1wy ~ 7637. 2 ~pecimens figured; ]552-1-). Outside distrihution.-Arkansas: Naca· toch sand. Tennessee: Coun Cn~ek tongue of Rip­ley formation. ·:Mississippi: Owl Creek formation. Chattahoochee reg i on (Alabama. Georgia) : Ripley formation (upper part) and Providence sand. Range.-In Texas the species has been recorded onlY from the Corsicana marl, r·ut the knm\:n stratigraphic range of the species in the Gulf region is somewhat longer than this, it having been recorded from the l\acatoch sand of Arkansas, from the lower part of the Ripley formation (Coon Creek tongue) of southern Ten· nessee. from the Ow1 Creek formation of Mississippi. and from the Ripley forma· tion and ProYidence sand of the Chatta­hoochee region. The species has not been found stratigraphically lower than the E:rogyra costata zone. Superfamily }\1YTILACEA Family 1\IYTILIDAE Genus VOLSELLA Scopoli Type speries.-'"Mrr;/us" modz"olu.s Linne. The ya]idity of V olsella Scopoli versus M odiolus Lamarck. seems to have been ~atisfaetorily settled by Gray,19:! Meek,133 and Stewart.ui4 VOLSELLA UDDENI Stephenson, n.sp. Pl. 25, figs. 18, 19 Shell wry thin~ small, greatly elongated, becoming oblique p~)steriorly, moderately Yentricose anterior!y and centrally, thin· ning out wedge-like posteriorly, gaping a little at the lower posterior extremity. A broadh-rounded. slightlv sinuous um· banal rid~e ~xtends fro~1 ti1e beak to the lower po~terior extremity and a broad, shallow radiating depression lies in front of the ridge. Beaks small, incurved, ap· proximate~ projecting well above the hinge l!•:!Gray. J. E.. Zoo!. Sor. London Proc., vol. 15, p. 198, 1817. lt'3.\fcck. F. B .. Rcpt. l'. S. Ced. Survey Terr., vol. 9, rr-69-71, 18io. l!+•Stewart, Ralph B., Acad. :\at. Sci. Philadelphia Proc., Spec.al Pub. :\o. 3, pp. 98-99, 1930. Invertebrate Fossils of the Navarro Gr.oup line, proaogyrate, situated less than 2 mm. back of the anterior extremity. The hinge is not clearly uncovered, but is about 10 mm. long; it is probably edentulous, and some of the broken edges suggest that there may be a long, narrow, shallow channel closely paralleling the hinge margin. Both lunule and escutcheon wanting. Dorsal margin nearly straight or very slightly arched; anterior margin rather sharply rounded; ventral margin long, slightly convex, becoming broadly concave a little back of the midlength; posterior extremity sharply rounded well llelow the midheight, passing upward into a long, broadly arched posterodorsal mar­gin which is strongly inclined forward and paues in a broad curve, convex upward, into the hinge line. The surface is covered with a series of closely, though somewhat irregularly spaced, gentle, concentric un­dulations; the impressions on the molds and the markings on the thin shell frag­ments adhering to the molds suggest that these undulations are strongest in the umhonal region, and on the posterodorsal 1lope, and tend to fade out somewha1 toward the margins. Numerous fine, very faint radiating lines, scarcely visible to the naked eye appear on the internal mold beneath the umbonal ridge of most speci­mens. Dimensions of the holotype: Length 22 mm., height 14 mm., thickness 7.8 mm. A few of the largest shells attain a length of as much as 24 mm. At the type locality the shells of this 1pecies were found in one or more con­cretions. The collection includes 60 or more individuals most of which are com­plete or nearly complete internal molds, with more or less of the thin shell ad­hering. Types.-Holotype, U.S.N.M. no. 76492; 20 selected unfigured paratypes, U .S.N.M. no. 76493. Named in honor of Dr. J. A. Udden. DUtribution in Te:m&.-Navarro group, Neylandville marl: ?3% miles west-north­west of Corsicana (16166); ?21h miles north of Corbet (16170). Navarro group, Nacatoch sand: Vicin­ity of Chatfield ( 762, type loc.) ; field 2 miles southwest of Kaufman (7547) ; 4 miles north of Corsicana ( 17366) . Genus CRENELLA Brown CRENELLA SERICA Conrad PI. 25, figs. 13-15 1860. Crenella (Stalagmium) serica Conrad, Acad. Nat. Sci. Philadelphia Jour., 2d ser., vol. 4, p. 281, pl. 46, fig. 23. 1907. Crenella serica Conrad. Weller, Geol. Sur­vey New Jersey, Paleontology, vol. 4, p. 510, pl. 56, figs. 7' 8. 1916. Crenella serica Conrad. Gardner, Mary­land Geol. Survey, Upper Cretaceous (2 vols.) , p. 624, pl. 36, figs. 16-18. 1923. Crenella serica Con~·ad. Stephenson, North Carolina Geol. and Econ. Survey, vol. 5, pt. l, p. 241, pl. 62, figs. 1, 2. 1929. Crenella serica Conrad. Dane, Arkansas Geol. Survey Bull. 1, pl. 24 (op. p. 136), fig. 7. (Figure only.) Shell small, equivalve, inequilateral, strongly ventricose, with very steep dorsal slopes, ovate in outline, with greatest dimension in the direction of the height. Beaks strongly prominent, incurved, ap­proximate, prosogyrate, situated centrally. The hinge is formed by a slight thickening of the shell just below the beak, and on the area thus formed are several small teeth slightly elongated vertically; these appear to be modifications of the marginal crenulations. The ligament (or resilium) is set in a long, narrow submerged groove which extends from the margin just hack of the teeth, backward and inward for about a millimeter. The margins form a nearly regular oval, and are finely crenulated on the inner side. The adductor scars are not very sharply outlined; the anterior one is large and greatly elon­gated, extending from well above the midheight, downward nearly to the ventral margin; the posterior one is much smaller, subovate in outline, situated below the midheight. The outer surface is delicately reticulated by numerous fine, radiating ribs, crossed by evenly spaced, concentric ridges which are more prominent and much more widely spaced than the ribs. Dimensions of the shell shown in plate 25, figures 14, · 15: Length 4. 7 mm., height 5.8 mm., thickness 4.5 mm. The sculpture on the Texas specimens appears to he a little more pronounced than that on typical shells from Eufaula, The University of Texas Publication No. 4101 J\labama, though otherwise they appear identical. The shell described by Wade19~ as Crenella serica Conrad, is a young Cor­bula, not a Crenella. Type.-The type, which came from Eufaula, Alabama, is probably lost. There are numerous well preserved speci­mens from Eufaula, in the collections at the United States National Museum. Two plesiotypes from Texas, U.S.N.M. nos. 76494, 76508. Distribution in Texas.-Navarro group, Corsicana marl: 2%> miles north by east of Malta (16159); 1%~ miles south by east of Oak Grove (16160); 5 3/10 miles east by north of Greenville ( 16161) ; 3 7/10 miles southwest of Campbell ( 1554 7) ; 5 miles southwest of Quinlan ( 15546) ; near Terrell (15544) ; 2 miles south of Corsicana (14118, 16167); 2~.f> miles east of Cooledge (13832, 14137) ; 81h miles north of Cameron (13865) ; 7 7/10 miles west of Cameron (14131);14 mile west of Kimbro (14129); 3%~ miles east by north of Manor (14127) ; Onion Creek, 21/2 miles west of old Gar­field (7605, 14049; 14156, 1 specimen figured; 15532) ; 1;2 mile below Martin­dale (7621, 15527); 1 3/10 miles north of McQueeney (15524); 1 3/ 10 miles south-southeast of Marion (13389) ; 2 miles east of Marion (Tex. Bu. 2395) ; Green road, 3,4 mile southwest of High­way 90, Bexar County (164.91) ; Salado Creek upstream from Highway 90, Bexar County (16671) ; well 7/20 mile south by west of St. Mary's University, Bexar County ( 16353, 16408) ; near Castroville (7665); well on G. A. Harper Survey, Medina County, at depth of 1045 feet ( 13844). Navarro group, Kemp clay: Branch 61/2 miles southwest of Currie (17377) ; 1 mile west of Odds (17373); 3 miles southwest of Stranger (17372); 2 miles northwest of Deatsville (14128) ; near Deatsville (764, 1 specimen figured; 14125) ; at depth of 800 feet in well 2 miles west of Groesbeck (13124) . Outside distribution.-Arkansas: Naca­toch sand and Arkadelphia mar1. 105Watlc, Bruce, L. S. Geo!. Survey Prof. Paper 137, p. 71, pl. 23, figs. 9, 10, 1926. Mississippi: Ripley formation, Owl Creek formation, and Prairie Bluff chalk. Central and west-central Alabama: Prairie Bluff chalk. East-central Alabama and Chattahoochee region (Alabama-Georgia) : Ripley for. mation (upper part) and Providence sand. South Carolina: Upper part of Peedee formation. Maryland: Monmouth formation. New Jersey: Recorded (but not con· firmed) from the Marshalltown forma­tion; Red Bank sand. Range.-In Texas the species has not been recorded from any beds stratigraphi· cally lower than the Corsicana marl but it has been found at several localities in the N acatoch sand of Arkansas. Else­where in the Coastal Plain the species occurs chiefly in the beds having the strat· igraphic position of the upper part of the Exogyra costat,a zone, except in northern Mississippi where it is present in the lower Ripley (Coon Creek tongue). In New Jersey Weller196 records it from the Marshalltown formation (upper part of Exogyra po·nderosa zone) , hut the illus· trations of shells from the latter forma· ti on do not show the surface ornamenta· tion in sufficient detail for critical com· parison with typical shells of the species. Unidentified specimens of CRENELLA The internal and external molds of a single individual of Crenella (pl. 25, fig. 16), found in the Neylandville marl at a locality on the Corsicana road, 21/2 miles north of Corbet, Navarro County (16170), appears to be nearly smooth, but very fine radial striations can he faintly seen on the external mold. In form and size it is like C. serica, except that the beak is much less strongly prosogyrate. The speci­men is too poorly preserved to serve as a type. U.S.N.M. no. 76495. An incomplete internal mold of a pe· lecypod, probably the right valve of a Crenella (pl. 25, fig. 17) from the Naca· toch sand, at a locality 3t4 mile east of ~ha.tfield.' Navarro County (7571), is s1m1lar m form and outline to Crenella 106Wcller, Stuart, GeoI. Survey New Jerscy, Paleontology, vol. 4, p. 510, pl. 56, figs. 7, 8, 1907. Invertebrate Fossils of the Navarro Group elegantula Meek and Hayden,191 a large 1pecies from the Fox Hills sandstone of Wyoming. The mold is about 7 mm. long and is considerably larger than any known specimen of Crenella serica, but is smaller than the type specimens of C. elegantula. The impressions of fine, closely spaced radial ribs appear on the mold and a narrow remnant of shell just above the ven­tral margin preserves the ends of the ribs which appear to be very much like those of the Fox Hills species. The ribs are low, are wider than the interspaces, and num­ber 7 or 8 to the millimeter. (U.S.N.M. no. 76496.) The left valve from the Mon­mouth formation of Maryland, which Gardner198 referred to C. elegantula, ap­pears to be proportionately a little shorter, narrower in the umbonal portion, and per­haps a little more convex than that species, though a good suite of specimens might show these to be individual variations. The Texas specimen, though it cannot be referred with certainty to C. elegantula, is very close to it, and should be given considerable weight in the correlation of the Navarro group with the Fox Hills eandatone of Wyoming, and with the Monmouth formation of Maryland. An incomplete specimen of Crenella, larger than C. serica, but smaller than C. elegantula, and having fine radial ribs like the latter species, was secured from the Kemp clay at an earthern tank west of a public road, 2 miles south-southeast of Schumansville, 9/10 mile south-south­east of the crossing of Long Creek, Guadalupe County (16668). U.S.N.M. no. 76497. Cenua LITHOPHAG.A Bolten LITHOPHAGA CAROLINENSIS (Conrad) Pl. 22, figs. 18, 19 1875• .A.rcoperna carolinensis Conrad, Geol. Sur­vey North Carolina Rept., vol. 1 (by W. C. Kerr), App. A, p. 5, pl. 1, fig. 6. 1923. Lithoplaaga carolinensis (Conrad) . Steph­enson, North Carolina Geol. and Econ. Survey, vol. 5, p. 243, pl. 62, figs. 4--9. BrJileek. F. B•• and Hayden, F. V., Acad. Nat. Sci. Plalladelphia Proc., vol. 13, p. 441, 1862; Rept. U. S. GeoL Saney Terr., Toi. 9, p. 75, pl. 28, &p. 6, a, b, c, 1876. -c.rdner, Julia A.. Maryland GeoL Survey, Upper Cntaceou (2 woll.), p. 625, pl. 36, fie. 19, 1916. Shell thin, elongate, subcylindrical in form, suhelli ptical in outline, thinning wedge-like posteriorly. Beaks nearly ter­minal, strongly incurved, prosogyrate. The umbonal region hack from the beak is broad and flattened, the flattened area passing downward into a broad, shallow depression which becomes somewhat pro­nounced toward the ventral margin. A broadly rounded, inflated umbonal ridge extends backward curving gently down­ward to the extremity; the anterior end is less strongly inflated. The hinge is not exposed in the Texas shells hut in closely related species is edentulous and thin, and the inner surf ace of the shell is smooth. The anterior margin is evenly rounded; the ventral margin is long and broadly concave; the posterior margin is rather sharply, though evenly rounded, below the midlength, and passes upward into a hroadl y arched posterodorsal mar­gin; the dorsal margin is gently arched. The surface is smooth with the exception of fine growth lines and somewhat irreg­ularly developed growth plications. Dimensions of the shell shown in plate 22, figures 18, 19: Length 12.6 mm., height 6 mm., thickness 6 mm. Lithophaga ripleyana Gahb,199 from the "Ripley group" of New Jersey, may be identical with L. carolinensis (Conrad) , hut it has not been possible to make a satisfactory identification. The Texas shells seem to agree fairly well with his description but he did not figure his type material. A specimen in the Academy of Natural Sciences of Philadelphia, marked type in Gabb's handwriting, is so thor­oughly enclosed in a secreted covering that the form of the shell cannot be seen. A specimen figured by Whitfield as one of the originals (his pl. 17, fig. 4), is also encased in a secreted covering which obscures the form of the shell. A group of molds of the same kind from Mullica Hill, New Jersey, figured by the same author (his pl. 17, fig. 5) , are said by him to have been borings in wood. The shells from North Carolina and Texas are borers in the thick shells of other mollusks. 188Gabb, Wm. M., Acad. Nat. Sci. Philadelphia Proc., vol. 13, p. 326, 1862. The Unfrersity of Te~tas Publication No. 4101 Litlzophaga lingua Gardner,:.?00 a rather thin and an unusually high species pos­teriorly, may be a V olsella.. The shell from Tennessee referred by Wade:?01 to L. ripleyana, appears to be proportionately too high and too thin for that species; the specimen shows evidence of lateral crushing, but it seems doubtful if it ever could have been as plump as that species. Type.-The whereabouts of Conrad's figured specimen from Snow Hill, North Carolina, is unknown. Topotypes were figured by the present writer in 1923, U.S.N.M. nos. 31713-31715. One plesio­type from Texas, U.S.N.M. no. 76498. Distribution in Texas.-Navarro group, Nacatoch sand: West of Campbell ( 12925) ; ?vicinity of Kaufman (761). Navarro group, Corsicana marl: 2 miles south of Oak Grove (12932) ; 11,!i. miles south by east of Oak Grove (16160) ; 4 miles southwest of Quinlan (17385) ; Onion Creek, 21/2 miles west of old Gar­ 21 field (14156, 1 specimen figured) : ·~ miles west of McQueeney (15523) ; 2 miles east of Marion (Tex. Bu. 2395) ; ?Salado Creek, upstream from Highway 90, Bexar County (16671). Navarro group, Kemp clay: 2 miles northwest of Deatsville (14128); ?41A~ miles east-northeast of Cooledge ( 17374) ; ?branch 61/2 miles southwest of Currie (14.139). Outside distribution.-North Carolina: Snow Hill member of Black Creek for­mation. Range.-The range of the species ap­pears to be from the upper part of the Exogyra ponderosa zone through the E. costata zone. Genus CUNEOLUS Stephenson, n.gen. Type specie~.-Dreissena tippa11a Conrad. Etymology.-Diminutive of ctrneus~ a wedge. In form and general appearance this ~enus is ,-ery much like Dreissena Yan Beneden (emend Dreissensia of authors), the ~enotype of which is the Recent Mytilus polymorplws Pallds. Evidence ~GarJnt'r, Julia. :\l.iryLinJ Geo!. ~unev, l"pper Cretace­ou' (:!vols.), pp. 619. 6:!1 . 1916. !!'•1\\'aJe. Bruce. i· -~. Ct ul. ~u1. •'Y Prof. P..111·-r 137. p. iO, pl. ::!3, fig!!. 5. 6. }•J;!I~. has been gin·n. howen·r. to show that this resemblance i~ onh· superficial. Discussing the relationship of the Cretaceous Drei.s­sena tippana Conrad to the Hecent genera Con~eria and Dreissena. Bog~ild:.!o:! says: "AnL entire contrast to the abO\·e-named, recent forms is a Drcissensia tippana from the Senonian Ripley formation, the shell of which is nacreous throughout; there is no trace left of any calcitic layer." Cox~00 discusses the same subject as follows: The more or less rhomboidal. obliquely elon­gated shape of the shell and the terminal or subterminal position of the umhones in Mytilus and similar genera may be considered an adapta­tion to the particular mode of growth of these forms, which are suspended from other objects by a byssus protruding from between the antero­ventral margins. That shells so characterized may have 01 iginated, by convergence. from unrelated stocks is shown by the Recent genus Dreissena [or Dreissensia]. whose anatomical characters in· dicate it to be . quite unrelated to M_rtilus and even to belong to a different order, the Eula· mellibranchiata. Again on page 3-1-6 Cox says: In these forms [Dreissrna tippana Conrad and others]. however, the structure of the hinge-region agrees with that of normal representatives of the -'lytilidae. and a further new subgenus of Mytilus should probably be established for their recep­tion. I do not consider them to be related to Dreissena. which probably ernhed in Tertiary time~ from some genus of the Eulamellibranchiata which was not at all mytiliform in shape. Accepting the opinion of these authori­ties that Dreissena tippana Conrad is ge­nericalh-distinct from the Recent Dreissena Yan Beneden. and in Yiew of the great time interval that separates them, I am proposing the new generic name Cuneolus to include Conrad·s specie3 and other closely related Cretaceous species, among them Mytilus lanceolatus J. de C. Sow­erby,~ot and .l/. tegullatus 1\-liiller.:.?os !:.'l12Blll;!gilJ. 0. B., The shell structure of the mollusks: :\fem• .-\ca•l. Roy. Sci. Lcttrt'S Denmark. Sec. des Sciences, scr. 9, ml. 2. pp. 273, 1930. :.~'3Cox. L. R .. On a new subi!cnus of .l/ytilus and a new .llytilus·likc j!enus: Prue. :\labc. Soc., London, vol. 22, pt. 6, p. 339, 1937. !))j'Woods, H.. Monogrjph of the Cretaceous Lamel· libranchia of England, vol. 1. p. 110, pl. 19, figs. 1·11. (Referred to Drt'issensia.) :!OS~[iiller, Jost' ph, ~lo:10gr..1phie d~'r Petrefacten d~r Aachener Kre:ddormation. p. 35, pl. ::?a, b, 18.U. Invertebrate Fossils of the Navarro Group Cuneolus is a falcate, mytiliform shell of moderate size, convexity, nnd terminal pointed beaks. An acutely angular rida; extends in a broad curve convex upward, from the beak to the posteroventral margin; this ridge slightly overhangs the broadly concave, downward-facing an­teroventral surface. The hinge is narrow, edentulous and bears a long, narrow, shallow, broadly arched, partly sub­merged ligamental groove. The anterior a~ductor scar is seated on a well developed triangular umbonal septum resembling that of DreisseTUl, but less deeply sunken below the margins of the shell. On the figured neotype the bottom of this shallow septal depression is nearly smooth, but on other specimens it is obscure} y marked with irregular radial lines; at the forward end of the septum of the right valve of the neotype is a slightly more sunken, small ovate shallow pit, and at a corresponding position on the left valve a transverse non­prominent protuberance. On each valve the ligamental groove is separated from the septal depression below by a lonu narrow ridge or nymph, and the groov: extends forward reaching the anterior margin just below and a little back of the tip of the beak. The posterior adductor scar as seen on the right valve of the neotype is narrow, greatly elongated, and somewhat irregular in width; its posterior end lies within 4 mm. of the sharply rounded posterior margin, and its forward end reaches nearly to the posterior end of the hinge. In form and in the shallowness of its septal depression this genus resembles lyceuia Cox,206 from the Inferior Oolite England, but it lacks a medium toothlik~ protuberance on the septum in the um­bonal angle. Cox is undecided a'S to whether Lycettia should be included in the Mytilidae, or should he regarded as a descendant of the Ambonichiidae or the Myalinidae of the Paleozoic. CUNEOLUS TIPPANUS (Conrad) Pl. 25, figs. 20-26 1858. Dreissena tippana Conrad, Acad. Nat. Sci. Philadelphia Jour.., 2d se:-., vol. 3, p. 328 p. 34, fig. 14. , -Op. cil., p. 345. ?1916. Dreissena tippana Conrad. Gardner, Maryland Geol. Survey, Upper Creta­ceous (2 vols.), p. 628, pl. 37, figs. 8-11. ?1926. Dreissensia tippana Conrad. Wade, U.S. Geol. Survey Prof. Paper 137, p. 72, pl. 23, figs. 11, 12. Shell of moderate size, falcate, elon­gate, equivalve, inequilateral stronO'lv ' b J convex; posteroventral margins of the two valves gaping slightly about midway of their length; shell wall of moderate thickness. Beaks acute, terminal, pointed forward. An acutely angular ridge ex­tends in a broad curve, convex upward, from the beak to the ventral margin· this ridge slightly overhangs the anterov;nt.ral surface which is broadly concave facinu downward and forward; back of the ridg~ the surface rounds off regularly and steepIy to the dorsal and posterior mar­gins. The hinge is not exposed in the Texas material, hut in well preserved shells from Mississippi it is narrow, edentulous, and is I 0 mm. or more in length in adults; the hinge bears a long, narrow, shallow, partly submerged liga­mental groove. In the Mississippi ma­terial there is a well developed umbonal septum on which the anterior adductor muscle is seated; the inner surface is smooth and pearly. The posterior muscle sc.ar is . long, narrow, and of irregular width; 1t extends from near the posterior end of the shell nearly to the terminus of the hinge. Anteroventral margin broadly concave; posteroventral margin sharply rounded; the posterior and posterodorsal ma:gins form a broad, regular curve wh1?h passes upward into the short nearly straight dorsal margin. The outer surface i: smooth with the exception of fine growth Imes and numerous rather weak plications which mark resting stages. Dimensions of the specimen shown in plate 25, figures 25, 26: Length 26 mm., height 28 mm., thickness 16.5 mm.; great­est measurable dimension 33 mm. The Texas shells from the Nacatoch sand are very similar in size and form to the ~ew available shells from the type lo?al.1t~ o~ Ow1 Creek in Tippah County, M1ss1ss1pp1. The specimens figured by Wade under this name are proportionately broader and less inflated than the typical The University of Tc.ras Publication No. 4101 shells. Tlw shell from the Monmouth formation of :i\'1 an·land, desrrilH'd hv Gardner undPr this .specific name, is ah•;) broader and less i n_flated than the typical shells. If tlwsc dilierences should prove to be constant they would seem to justify the separation of the Tennes5ee and Mary­land shPIIs as a subspecies or species. Types.-The holotype, which should be in the collection of the Academy of Natural Scienccs of Philadelphia, is ap­parently lost. Neotype from the type locality on Owl Creek, 21/2 miles north­east of Ripley, Tippah County, Mississippi, U.S.N.M. no. 76499 ~ 2 topotypes, U.S.N.M. nos. 21683, 76500. One plesio­type from Texas, U.S.N.M. no. 76501. Distribution in Te.'ras.-N~varro group, Nacatoch sand: Vicinity of Kaufman (761, 1 specimen figured; 14098). Navarro group, Corsicana marl: ~6 mile below Martindale (15527). Outside distribution.-Mississippi: Rip­ley and Owl Creek formations. Chattahoochee region ( A l a b a m a ­Georgia) : Questionably in the Riolev formation (upper part), and in the P;ovi­dence sand. Maryland: Questionably in the Mon­mouth formation. Range.-In Texas the species has been found in the Nacatoch sand and in the Corsicana marl, of the Navarro group. The same or closely related varietal forms occur in the E.t:ogyra costata zone of the Atlantic and GuIf Coastal Plain at least as far north as Maryland. Order ANO\IALODESMACEA Superfamily ANATINACEA Family PHOLADOl\IYACIDAE Genus PHOLADOMYA Sowerby PHOLADOMYA LITTLEI Gabb Pl. 17, fig. 7 1876. Plwladomrn littlt•i Gabli, A"ad. Nat. Sci. Philadelphia Proc., vol. 28, p. 305. 1905. Pholadom_rn littlci Gahl>. John:-1011, Acad. Nat. Sci. Philadelphia Proc., vol. 57, p. n. 1923. Plwlwlomrn littlci Cabh. Stephenson, North (:arolina C1·ol. and E('on. Survey, ml. 5. pt. 1. p. :247, pl. 63, fig~. 1. 2 (not fiE!s..), -l I ; pl. M, pl. 65~ fig. 10. Shell large, subequivalve, inequilateral, subcll i plical in outline, most ventricose centrally, rounding down steeply toward the front and thinnin~ gradually toward the rear; valves gaping a little both anterior!y and posterioriy; shell wall thin. Beaks broad, moderate!y prominent, in­curved, approximate, situated one-third the length of the shell from the anterior ex­tremity. Hinge margin long, straight; hinge not uncovered in available material. Anterior adductor scar obscure; the pallial line is marked by a band of trans­verse corrugations, 6 to 8 mm. wide, and ascends steeply anteriorly; pallial sinus profound, extending to center of shell, low on inner surface, nearly horizontal. On one of the cotypes the ligament, the form and substance of which are in part pre· ~erved, is paravincular, opisthodetic, short, and stands prominently above the margins of the valves~ its surface is marked by fine transverse lines, and its structure is fibrous. The ligamental groove is a nar· row slit. Anterior margin sharply rounded above the midheight; ventral margin long and broadly rounded; pos­terior margin sharply rounded at about the midheight. Surface marked by rather coarse concentric growth lines and undula· tions, and by 10 to 13 strong, narrow, :=wute, somewhat irregularly spaced costae which are closest together centrally. The anterodorsal slope is ribless. The ribs are reflected on the inner surface as radial· ing depressions. Dimensions of the largest cotype: Length 152 + mm., height about 100 mm., thickness about 80 mm. This species is represented in the col­lections from Texas by one large, badly crushed individual in which both valves are present but incompletely preserved. The description is based chiefly on the cotypes from Pataula Creek, Georgia. The species is the largest recorded repre· sentative of the genus in the Upper Cre­tneeous series of the Atlantic and Gulf Coastal Plain. T:v pes.-Two cotypes in the collection of the Academy of Natural Sciences of Philadelphia. They are imperfect in· ternal molds from the upper part of the Ripley formation on Pataula Creek, Clay Invertebrate Fossils of-the Navarro Group County, Georgia; on the smaller specimen portions of the shell still adhere. Plesio­type from Texas, U.S.N.M. no. 76502. Di&tribution in Texas.-Navarro group, Nacatoch sand: 6 miles southeast of Cooper (12929, figured). Outside distribution. -Chattahoochee region (Alabama-Georgia) : Providence sand. North Carolina: Upper part of Peedee formation. Range.-The species is restricted to the Exogyra costata zone of the Upper Cre­taceous in the Gulf region and the Caro­linas. PHOLADOMYA sp. The internal mold of the anterior por­tion of a small left valve, with some thin shell substance adhering, from the Kemp clay on Guadalupe River, a third of a mile upstream from the Galveston, Harris­burg, and San Antonio Railroad bridge at McQueeney, Guadalupe County (7632), is rather plump, somewhat elongated, and evenly rounded on the anterior margin; it exhibits on the preserved portion 13 or 14 irregularly spaced, sharp, narrow ribs, and rather coarse growth plications. The beak is not preserved, but is evidently sit­uated well toward the front. The speci­men is inadequate for a complete specific description, and it may he a young m­dividual. U.S.N.M. no. 76503. Genus HOMOMYA Agassiz HOMOMY A 7 THRASHER! Stephenson, n.sp. Pl. 25, fig. 12 Shell small, thin, subtrapezoidal in out­line, inequilateral, probably equivalve, moderately convex ; umbonal ridge broadly rounded, dorsal slopes moderately steep. Beaks not well preserved but ap­parently broad, not very prominent, in­curved, situated about one-fifth the length of the shell from the anterior extremity. Hinge and internal characters not unco~­ere3) : north edge of Cor­sicana t 518. 1 specimen fif!u~red) : 2~ ~ miles north of Corsicana t)-111-1'1. "\arnrro group. Corsicana marl: 2 3 5 miles north bY east of l\lalta (16159) : 1 •) mile belo~,-\lartindale (15527) : 2 n;iles east of :\larion I Tex. Bu. 2395) : 6 miles east of CastroYille ~ 16156~ Tex. Bu. 3282L Outside distribution.-A.rkansas: Sara­tr.ga chalk and "\acatoch sand. Tennessee: Coon Creek tongue of Rip­}ey formation. ::\Iississippi: Prairie Bluff chalk and Owl Creek formation. Central and west-central Alabama: Prairie Bluff chalk. East-central Alabama and Chattahoochee region I Alabama-Georgia) : Ripley forma­ tion I upper part) and PrO\·idence sand. South Carolina: Peedee formation (up­ per part). \Ian·land: 1\fonmouth formation. :\ew. Jersey: "~enonah sand, NaYesink marl. and R~d Bank sand. Range.-This species has been col­ lected mainh-from the Exol!:rra costata zone of the. Atlantic and G~lf Coastal Plain. hut a few specimens which appear to be doseh· related to if not identical with. the sp~eies. ha,·e been found strati­ graphicall~-lower in the Exogyra ponder­ osa zone in the Anaeacho limestone and in the Wolfe City sand member of the Taylor marl. in Texas. and in the upper part of the \latawan group of .Maryland. LIOPISTHA FORMOSA Stt-phenson, n.sp. Pl. 26. fi~~. 2+ -26 '?19~6. Liopistha in.flata Whitfield. Wade. U.S. Ct•ol. ~urwy Prof. Paper 137. p. 76, pl. ~-l. fig~. 7. 8. ~lwll similar in form and outline to L. protcxta hut with umbonal region more prominent aboYe the dorsal margin. Hinge llf•t ex posed. Li!!amental !!roo,·e external. short. opi~thodetic. The L adductor scars which can be onh· obscureh-seen on one mold are of moderate size. and are sit­uated high up under the dorsal margin. The surface is ornamented with 20 to 26 low. relati\·el y broad~ rounded~ radiating ribs on which can be seen the scars of small tuhNdes: these ribs are larger posteriorl ~-than anteriorly and on one specimen with ~hell prescn·ed some of the larger ribs t>ach exhibit 9 or l 0 very faint, radiating: lines: the rather broad antero· dorsal and posterodorsal areas are smooth, or onh fainth-ribbed. This species, like L. pr~tcxta, . exhibits in the umbonal region. 10 or 12 eYenly spaced, gentle con· centric undulations. Dimensions of a small, but nearly per· feel internal mold: Length 18 mm., height 13 mm.. thickness 10 mm. The specimen figured by Wade as Uopistlza inflata "'Whitfield is very close to L. form osa, but is more sharply rounded and more pointed posteriorly. The species differs from L. protexta (Con· rad) in its fewer and less acute ribs, in the obscurity of tubercles on the ribs, and in the son;ewhat greater prominence of the mnbonal region aboYe the dorsal margin; the shell probably also averages a little shorter in proportion to the height, and is more e\·enly rounded on the upper part of the posterior margin. Compared with L. inflata '\'?hitfield this species is much less inflated and is narrower in the umbonal 1egwn. Types.--Holotype, U.S.N.M. no. 20897; 1 figured paratype, U.S.N.M. no. 21062; 1 unfi~ured paratype, U.S.N.M. no. 76516; I unfigured paratype, U.S.N.l\.'I. no. 76515. Distribution in Texas.-Na\'aJTo group, "\acatoch sand: North edge of Corsicana 1518. I specimen figured); vicinity of Cor· sicana I 763, holotype, figured, and 3 paratypes) ; Yicinity of Chatfield (762, l figured paratype) : field s3uth of Chatfield ( 75691 : 1 -J;f:> miles northea5t of Quinlan ( 161621. Outside distribution.-Tennessee: Lower part of Ripley formation (Coon Creek tongue 'I. Range.-So far as known the species is restricted to the lower and middle parts of the E:rogyra costata zone of the Gulf Coastal Plain. Genus CYMELLA Meek 186-1. Cymella \leek. Check list of the inverte­brate fo~sil~ of North America, Creta· ceous and Jurassic: Smithsonian Misc. Coll., vol. 7. no. 177, p. 34. Invertebrate Fossils of the Navarro Gr.oup 1875. Cymdla Meek. Conrad, Geol. Survey North Carolina RepL, vol. 1 (by W. C. Kerr), App. A, p. 10. 1876. CymeUa Meek, RepL U.S.Geol. Survey T.err., vol. 9, pp. 227-237, text figs. 25--30. (Subgenus of Liopistlaa.) 19'23. CymeUa Meek. Stephenson, North Caro­lina Geol. and Econ. Survey, vol. 5, p. 253. (Subgenus of Liopistlaa.) Type speci.es.-Lwpistlaa (Cymella) montanensis Henderson ( =Pholadomya undata Meek and Hayden= Liopistlaa (Cymella) un­data Meek and Hayden). Meek regards Liopistha and Cymella as falling within the same generic group, but he rather hesitatingly treats Cymella as a subgenus, the separation being made mainly on differences in external or­namentation. Meek's detailed description of the hinge characters was made with the hinges of both Liopistha and Cymella before him. Although the two groups ex­hibit a general similarity of form they are strikingly different in their types of ornamentation. On Lio pistha the radial ribs are numerous, rather sharp crested, and hear small tubercles or spines more or less distinctly developed on their crests; concentric ribbing is subordinate and is restricted to the umhonal region near the beak. Cymella possesses lltrong concentric ribs which are crossed on the central part of the shell by a few, relatively weak radials; these radials bear tiny spines aimilar to those on Lio pistha, as shown by spine scars on well-preserved specimens from the Western Interior. Each group includes several species. These differences in ecul pture are believed to be a sufficient basis for regarding the two groups as gen­erically distinct in spite of the similarity of their hinges. CY'MELLA BELLA TEXANA Stephenson, n.var. Pl. 26, figs. 21-23 1911. Cymella bella Conrad. Miller, Maryland Geol. Survey, Prince Georges County RepL, p. 96, pl. 5, fig. 10. (Figure only.) Shell suhovate in outline, subequivalve, inequilateral, moderately ventricose, most inflated above the mid.height and some­what in advance of the midlength, becom­ing compressed posteriorly, probably slightly gaping posteriorly; shell wall thin. Beaks moderately prominent, broad, llrongly incurved, approximate, slightly prosogyrate, situated a little in advance of the midlength. Lunule about 8 mm. long in the holotype, rather broad, smooth, and excavated. Escutcheon long, narrow, rather deep, separated from the main surface of the shell by a pronounced., dull-crested carina, outside of and parallel to which is a shallow channel against which the concentric ridges of the main surface end. Hinge and internal features not uncovered. Anterior margin regularly rounded, curving sharply into the dorsal margin above; ventral margin broadly and regularly rounded; posterior margin sharply rounded with a short subtrunca­tion above the extremity; dorsal margins sloping gently away from the beaks, the anterior one slightly arched. Surface orna­mented with about 22 rather strong, broad, concentric ridges with narrow interspaces; the ridges become progres­sive! y broader from the beak toward the ventral margin, the last one being about 1.5 mm. wide; each of these ridges ter­minates above at the edge of narrow, unribhed areas bordering the dorsal margins. A group of a dozen or more rather broad, round-crested radiating ribs, with narrower interspaces, extend from the beak down over the central part of the shell, leaving a little more than the anterior fourth and the posterior fourth, unribbed; the channels between the concentric ridges cut the radiating ribs, giving to the central part of the shell a checkered appearance; the radiat­ing ribs exhibit considerable variation in their number and spacing on different individuals, an extreme example of which is afforded by the paratype shown in plate 26, figure 21. This shell is very similar in size, form, and outline to the typical Cymella bella Conrad from the Snow Hill member of the Black Creek formation (upper part of Exogyra ponderosa zone) in North Carolina, hut it differs in having broader and more numerous radiating ribs with narrower interspaces. In places in the Exogyra porulerosa zone, as in the San Miguel formation of the Rio Grande region, the shells of this group show considerable variation, from those having the relatively few and typically narrow costae of C. bella to those having more and broader The University of Texas Publication No. 4101 costae like C. bella texana, and some of the intermediate forms must be referred to one or the other form rather arbi­trarily. But shells from the higher Exogyra costata zone, including those from the Navarro group, and beds of correspond­ing aµ;e, appear to be constantly more like C. bella texana; it is therefore con­venient to have a separate name for this form. Types.-Holotype, U.S.N.M. no. 76517; 2 figured paratypes, U.S.N.M. no. 76518. Distribution in Texas.-Upper part of Taylor marl: ?On the Burlington roa mile west of Kaufman (75l5; 14098, loc. of holotype) ; field i~·~> mile west of Kaufman (1·1103); vicinity of Kaufman (761. 2 figun·d paratypes) : field 2 miles southwest of Kaufman (75.l/). Outside dist ribution.-Arkansas: Naca­toch sanrrh as the Nacatoch sand. The range in the Atlantic and Gulf Coastal Plain is from the Exogyra ponderosa zone upward through the E. costata zone. Family CUSPIDARIIDAE Genus CUSPIDARJA Nardo CUSPIDARIA GRANDIS Stephenson, n.sp. Pl. 26, fig. 31 Shell large, pyriform, strongly inequi­lateral, rather strongly ventricose cen· trally and anteriorly, becoming com· pressed, narrow, and rostriform poster· iorly, with a broad, shallow, sinuous su lcus extending from the beak backward and downward to the posteroventral mar· gin; shell wall thin. Beaks broad, strongly incurved, approximate, slightly opistho· gyrate, situated at about the midlength. Hinge and internal features not observed. Anterodorsal margin short; anterior mar· gin regularly, almost sharply, rounded; ventral margin broadIy and evenly rounded, rising high posteriorly, becom· ing slightly concave where the radiating sulcus intercepts it, straightening out again toward the extremity; posterior part of the shell broken, but apparently rather lonrr, narrow, and sharply rounded, or perhaps slightly truncated posteriorly; posterodorsal margin long, slightly con· cave. Surface ornamented with numerous subregular, sharp, concentric ridges, with much wider interspaces on which 4 or 5 fine, concentric lines can be seen on well preserved parts. Dimensions of the holotype, a left valve: Length about 29 mm., height 16.8 mm., convexity about 7 mm. This species is comparable in size, form, and concentric markings to Cuspi· daria jerseyensis Weller, from the Nave· sink marl (Monmouth group), New Jer· sey. The Texas shell, however, is some­what more finely sculptured, and lacks Invertebrate Fossils of the Navarro Group radiating lines which can be seen ob­scurely on the umbonal portion of the type of jerseyensis. Internal molds of similar large shells occur in the Prairie Bluff chalk (upper part of Exogyra costata zone) , in Oktib­beha County, Mississippi; the concentric sculpture on these shells has about the same degree of coarseness as that on C. jerseyensis. Holotype.-U.S.N.M. no. 76519. Distribution in Texas.-Navarro group, Corsicana marl: 1 3/10 miles north of McQueeney (7637, type Ioc.). Navarro group, Kemp clay: ?4 miles south of Corsicana ( 9550) ; ?Brazos River, 2 miles above Milam County line (13776). CUSPIDARIA GROVENSIS Stephenson, n.sp. Pl. 26, fig. 32 Shell small, thin, strongly bulbose an­teriorly, becoming sharply contracted posteriorly, both with respect to inflation and the height of the shell, ending almost in a point at the posterior end of the hinge line. Beaks strongly prominent, in­curved, approximate, situated about 0.4 the length of the shell from the anterior extremity; the bulbose portion of the shell is slightly elongated in a line trending upward and downward, but the top of the beak is slightly prosogyrate. Hinge and internal features not uncovered. Postero­dorsal margin straight, horizontal, ex­tending from below the beak backward to the extremity; a narrow sharply impressed sulcus closely parallels this margin; pos­terior extremity subpointed, posteroven­tral margin broadly concave; the ventral margin below the globose inflation, and the anterior margin together describe almost a semicircle; anterodorsal margin arched. Surface smooth with the excep­tion of fine growth lines which become coarser on the contracted posterior extension. Dimensions of the holotype, a left valve: Length 8 mm., height 5 mm., con­vexity about 2 mm. The largest specimen referred to the species is 11 mm. long. The species is meagerly represented by more or less imperfect material, and some of the specimens here referred to it may be found to belong to different species or varieties when more and better material is available. Compared with Cuspidaria moreauensis (Meek and Hayden) :?ou from the Fox Hills sandstone of the Western Interior, this species appears to be more strongly in­flated and the bulbose part more elon­gated and more oblique. C. ventricosa (Meek and Hayden) :!io is markedly less in­flated and more coarsely sculptured. Holotype.-A left valve, U.S.N .M. no. 76520. Distribution in Texas.-Navarro group, Neylandville marl: 2112 miles north of Corbet (16170, 17365). Navarro group, Nacatoch sand: 2 miles north of Corsicana (9554); 2Y2 miles northwest of Chatfield (Tex. Bu. 17303). Navarro group, Corsicana marl: 4 miles southwest of Corsicana ( 16165, type loc.) ; ?Onion Creek, 21/2 miles west of old Garfield (14156). Range.-Ranges through the three lower members of the Navarro group m Texas. Unidentified specimens of CUSPJDARIA A small internal mold of a short, only moderately ventricose Cuspidaria (pl. 26, fig. 33) was found in the Nacatoch sand in the public road east of the Houston & Texas Central R.R., near section house, 21h miles north of Corsicana, Navarro County (14114). U.S.N.M. no. 76521. A large internal mold of a right vake of Cuspidaria?, from the Nacatoch sand on land of E. A. Stevens, 14;5 miles north­east of Quinlan, Hunt County (16162), is strongly inflated anteriorly and strongly contracted posteriorly, but appears to have a much shorter posterior extension than typical species of Cuspidaria (pl. 26, fig. 34). Dimensions: Length 14, mm., height 11 mm., convexity 4 mm. U.S.N.M. no. 76522. A Cuspidaria from the Corsicana marl on the Mexia highway, 24;3 miles east­southeast of Cooledge, Limestone County (14137), is an incomplete external mold of a right valve about 7 mm. long, having 200Meek, F. B., Rept. U. S. Geol. Survey Terr., vol. 9, p. 239, pl. 17, figs. 11 , a, b, c, 1876. 210Meck, F. B., op. cit., p. 238. The University of Texas Publication No. 4101 a rather elongated form and only mod­erate Yentricosity lpl. 2(), fig. 35) ; its sur­face is marked by fine growth lines and by irregularly deYeloped growth plications. lT.S.l\'.M. no. 76523. Order TELEODES1\1ACEA Superfamily CYPRICARDI.ACEA Family PLEUROPHORIDAE Genus VENIELLA Stoliczka Type specie~.-Ve11ilia co11 radi Morton. Roudairia M unier-Chalmas:?11 (emend Roudiareia Fischer) from the upper Senonian of Tunis, North Africa, appears to be congeneric with Veniella, although slight differences in its hinge characters may justify its recognition as a subgenus. VENIELLA CONRADI (Morton) Pl. 27, figs. 6-8 1833. Venilia conradi Morton. Am. lour. Sei., vol. 23, p. 294, pl. 8, figs. 1, 2. 1834. Venz'.lia conradi .Morton, Synopsis of the organic remains of the Cretaceous group of the United States, p. 67, pl. 8, figs. 1, 2. 1862. Venilia trigona Gabb, Acad. Nat. Sci. Philadelphia Proc.• vol. 13, p. 324. 1869. Goniosoma inflata Con:-ad, Am. lour. Conch.. vol. 5. p. 44, pl. 1, fig. 10. 1870. Venilia elemta Conrad, Am. lour. Conch., ml. 6, p. 74-, pl. 3, figs. 7. 7 a. 1871. Veniella conradi (Morton). Stoliczka, Geol. Survey India ~lem., Palaeontologia lndica, Cretaceous fauna of Southern India. vol. 3, p. 190. (Veniella substi­tuted for the preoccupied Ven ilia.) 1876. Veniella conradi (1\lorton). Meek, Rept. U.S.Geol. Survey Terr., ml. 9, p. 148, text figures. 1885. Veniella conradi C\lorton). Whitfield, U. S. Geol. Survey ::\ton., vol. 9, p. 144, pl. 19, figs. 8-10. lGeol. Survey New Jersey, Paleontology. vol. 1, p. 144, pl. 19, figs. 8-10. 1886). ?1885. Veniclla inflata (Conrad). Whitfield, idem. p. 147. pl. 19, figs. -1, 5. 1885. V cniella elcmta (Conrad l. Whitfield, idem, p. U8, pl. 19. figs. 6. 7. 1885. Veniella trir:una (Gabb 1. w·hitfield. idem, p. 1-19. pl. 19. figs. 11-14. 1905. Veniclla ron radi C\lorton). Johnson, A cad. Nat. S<'i. Philadelphia Proc.• vol. 57, p. 13. (:\lso lists V. elemta (Conrad), and V. inflata (Conrad I, which he re· gards as synonyms of V. con radi.) :!ll\funiN-Chalmcs. \f.. '.\nt\' paleontoloi;!iquc sur les fos­ siles rl'CU<'illis par \I. le Co111111andant Roudairc dons son l'Xpt'.·1li:ion sri1·ntihque en Tunisit>. et description dt's 1·spc'·ct"8 n<1uvcll1·s : .Are1l. tic' s \ti~sinns Sc i. ct Lit., Troisi1·111e !ll'ric. Turu.· 7. JI. :l03, pl. -l, fii:!\. 1-7, 1881. 1905. Veniclla trigona (Gabb). Johnson, Acad. Nat. Sci. Philadelphia Proc., vol. 57, p. 13. 1907. V<'niclla rnnrwli (i\lorton). Weller, Geol. Survt'\' Nrw Jersey, Paleontology, vol. 4, p. s:r7. pl. 5526. Distribution in Texas.-Blossom sand: 1v.~ to 11/t miles south by west of the courthouse at Paris, Lamar County (13078). Taylor marl (upper part): Burlington road, 2 3/10 miles west-southwest of Rose­bud, Falls County ( 14135). San Miguel formation: Questionably on the Del Rio road, about 121h miles north­west of Eagle Pass, Maverick County (8226); ?on a private road, 1 7/10 miles east of the old Eagle Pass road, 16 miles northeast of Eagle Pass (10855). Navarro group, Neylandville marl: 2~/~ miles northeast of Royce City ( 16157) ; 31h miles west-northwest of Corsicana (16166). Navarro group, Nacatoch sand: Vicin­ity of Kaufman (761) ; field 3/ 5 mile west of Kaufman (14103) ; vicinity of Chat­field ( 762) ; field south of Chatfield (7569); vicinity of Corsicana (763); 2~,~ miles north of Corsicana (1-1114, 1 speci­men figured). Navarro group, Corsicana marl: 2 3/ 5 miles north by east of Malta (16159) ; ] % miles south by east of Oak Grove (13568, l(>l(>rru~inous, concretionary sandstone cropping out at two localities about ] 0 miles apart in Caldwell County. None of the shell material remains intact. The only representatives of the Astar­tidae heretofore recorded from the Upper Cretaceous of the Atlantic and Gulf Coastal Plain are 5 or 6 species of the genus Vetericardia, all of which are small, scarcely exceeding 10 mm. in length and exhibitinO' dentition more like that of the 0 typical Astarte than of the new genus Astartemya. Types.-Holotype, internal and external molds of a left valve, U.S.N.M. no. 76536; 1 figured paratype, U.S.N.M. no. 76537; 7 selected unfigured paratypes, U.S.N.M. no. 76538; Distribution in Texas.-Navarro group, Kemp clay: 3 1/ 5 miles north-north­west of Fentress (16149, loc. of holotype and 7 unfigured paratypes) ; 41;2 miles northwest of Lockhart (16151, 1 specimen figured). Range.-Known only from a restricted zone in the Kemp clay of the Navarro group in Caldwell County. Genus ASTARTE Sowerby ASTARTE? CULEBRENSIS Stephenson, n.ap. Pl. 26, figs. 9, 10 The description is based on the only available specimen, a right valve. Shell small, broadly subtriangular in outline, inequilateral, depressed convex. Beak nonprominent, incurved, prosogyrate, sit· uated about three-fifths of the length of the shell from the anterior extremity. Anterodorsal margin long, descending, broadly concave upward; anterior mar· gin rather sharpIy rounded, meeting the dorsal margin above at an obtuse angle; ventral margin broadly rounded, rising regular1y to the subangular posterior ex· tremity; posterodorsal margin slightly arched, rising steeply to the beak. Hinge and other internal f ea tu res badly cor· roded. One cardinal tooth on the right valve is oblique backward, and is strong and robust as on Astarte; the other fea· tures of the dentition are obscure. A nar· row groove along the inner anterodorsal margin receives the margin of the left valve. Surface ornamented with 7 strong, broadly round-crested concentric undula· tions which extend to the dorsal margins and end abruptly without curving around toward the beak. Dimensions.-Len~th 5.4 mm., height 4.6 mm., convexity 1.2 mm. Holotype.-A right valve, U.S.N.M. no. 76539. Distributio'n in T exas.-Navarro group, Corsicana marl: Well near the Culebra Invertebrate Fossils of the Navarro Group road, 7/20 mile south by west of St. Mary's University, Bexar County (16108). Genus VETERICARDIA Conrad 1869. Vetocardia Conrad, Am. Jour. Conch., vol. 5, p. 48. 1872. V etericardia Conrad. Acad. Nat. Sci. Phila­delphia Proc., vol. 24, p. 52. Type species.-Astartc crenalirata Conrad, from Eufaula, Alabama. Conrad explained in the second paper cited in the synonymy, that the original spelling, V etocardia, of this generic name, was an error, and should have been Veteri­ cardia. All subsequent authors have used the corrected spelling. The hinge of Vetericardia is striking I y like that of Astarte and, despite its radial sculpture, Wade:!12 apparently correctly in­cluded the genus under the family Astartidae. VETERICARDIA WEBBERVILLENSIS Stephenson, n.sp. Pl. 26, fig. 5-8 Shell small, relative! y thick-shelled, suhtrigonal in outline, equivalve, in­equilateral, depressed convex. umbonal ridge scarcely differentiated. Beaks non­prominent, incurved, prosogyrate, sit­uated slightly in advance of the midlength of the shell. Hinge of left valve with 2 strongly developed cardinal teeth, sepa­rated by a deep, triangular socket; the anterior cardinal is short, thick below and chisel-edged upward; the posterior cardinal is elongated, oblique, thick below, thinning to a chisel edge above. The anterior lateral is long, thin and mod­erate!y prominent; the posterior lateral dentition is bifid, the inner component long, weak distally, thick and moderately prominent centrally, and the outer one long, thin and nonprominent; the two components are separated by a long, nar­row, moderately deep socket. The right valve presents one prominent, faintly bifid cardinal, \1ery thick below, narrowing above, with deep, triangular sockets on either side. The anterior lateral dentition is bifid, the inner component being the 21:?Wade, Bruce, U. S. Geol. Sun·ey Prof. Paper 137, p. 78, 1926. stronger of the two, which are separaled by a long socket of moderate width and depth. The posterior lateral is long, thin, and prominent. Ligamental groove short, opisthodetic, and rather weakly developed. Lunule long and broad but weakly out­lined. Adductor scars of moderate size, the anterior one more elongated than the posterior one, situated about midway of the height. Above the anterior adductor is a smL~ll, weak pedal scar. Pallial line simple, moderately distinct in some speci­mens, glazed over and weak in others. Inner margin strongly crenulated. An­terior margin regularly, but rather sharply rounded; ventral margin broadly rounded; posterior margin regularly rounded; an­terodorsal slope slightly excavated; posterodorsal slope slightly arched. The surface of the holotype presents about 25 strongly developed concentric ridges, steepest on their upper slopes, which be­come stronger and more wide I y separated toward the ventral margin. Crossing the concentric ridges are about 35 weaker radials, separated by much narrower in­terspaces; these ribs produce broadly rounded nodes at their intersection with the concentric ribs. Comparison of dif­ferent individuals in the same collection shows that there is considerable variation in the number and the coarseness of both the concentric and radiating ribs. Dimensions of the holotype, a left valve: Length 5.2 mm., height 5 mm., convexity 1.5 mm. Dimemions of the Iarge left valve shown in plate 26, figure 8: Length 6.3 mm., height 6.1 mm., con~ vexity 2 mm. Vetericardia crenalirata Conrad, from the Ripley formation at Eufaula, Alabama, is a similar, but much more coarsely sculptured species, particularly with refer­ence to the concentric ridges. Vetericm;dia subcircula \Vade. from the Coon Creek tongue of the Ripley formation, Coon Creek, McNairy County, Tennessee, is also a similar species, but on it the radiating sculpture is obsolete except on the posterior slope where the ribs are very weak; the concentric ribs are sharper above, and pass into a smooth surface below. The University of Texas Publfoation No. 4101 Two of Wade's~1 :: species, V etericardia subangulata W a de and Vetericardia gregaria (Meek and Hayden) are incor­rect! y referred to Vetericardia; they prob­ably belong to the genus Crassatella. The second of the two species is also incor­rectl.y referred to Meek and Hayden's species. Types.-Holotype, U.S.N.M. no. 76540; l figured paratype, U.S.N .M. no. 76541 ~ l figured paratype, U .S.N .M. no. 76542; and 14 unfigured paratypes, U.S.N.M. no. 76543. Distribution in Texas.-Navarro group, questionably in the Corsicana marl: 5 miles southwest of Quinlan (15546) ; 2 miles south of Corsicana (16167) ; 2~!;; miles east of Cooledge (13832, 14137) ; 1/t mile west of Kimbro (14129); Onion Creek, 2% miles west of old Garfield (14049, 14156) ; ~,~ mile below Martin­dale (] 5527) ; well 7/20 mile south by west of St. Mary's University, Bexar County (16353). Navarro group, Kemp clay: Branch 61;2 miles southwest of Cur­rie (17377) ; well 2 miles west of Groes­beck at depth of 675-700 feet (13131), 730 feet (13132), and 800 feet (13124, 1 paratype figured) ; ?% mile west of Odds (15434) ; 2 miles northwest of Deatsville (14128); Webberville (7601, holotypc, l figured paratype, and 14 un­figured paratypes) ; west of Zuehl (7721). Range.---Specimens found at seven lo­calities in the Corsicana marl are poorly preserved and are questionably referred to this species. The remainder of the material came from the Kemp clay. Family C:RASSATELLIDAE Genus CRASSATELLA Lamarck The validity of Crassatella Lamarck versus Crassatellites Krueger is discussed hy Stewart,'.!1 ·1 who concludes that the for­ mer name, which is in general use m Europe, should be accepted as valid. It is doubtful, however, if unanimity of usage will be reached until the matter 213Wad1', Brun" l". S. Gt·ol. Survr.y Prof. Paper 137, pp. 78. 79, 19:.?6. :!HStf'wart, llalph. Arad. N:1t. Sci. Philad•·ll'!:ia Spec.al Pub. :\o. ~. pp. l.11 -137, 19.10. has been passed upon by the International Commission on Zoological Nomenclature. The genus is represented in the Navarro of Texas by two subgroups each of which, in a subdivision of the genus, would rank as a distinct subgenus. In the first sub­group, which includes If, varieties of the ~pecies Crassatella vadosa Morton, the resilifer on the left valve descends about halfway across the hinge plate, and is bordered below by the prominent lower end of a cardinal tooth which has become ~ent aro.und to this subligamental posi­t10n; this tooth hears a distinct!y im· pressed pit along its upper side; in the right valve the resilifer is bordered below by a sunken platform into which fits the aforementioned prominent tooth of the left valve. In the second subgroup, repre­sented by Crassatella quinlanensis, the resilifer descends in each valve to the inne~ hi~ge margin, and opens freely to the. mt~nor of the shell; this subgroup which is further characterized by its com· pressed form and pointed posterior ex· tremity, is represented in the eastern Gulf region by Crassatella ptero psis Conrad (not C. pteropsis Gabb). The holotype of Crassatella vadosa Morton'.!15 is from the Prairie Bluff chalk at Prairie Bluff, Alabama River, Wilcox County, Alabama, and is preserved in the collection of the Academy of Natural Sciences of Philadelphia. This was the first described species of a closely related ~roup of shells of this genus, which occur m great profusion at several localities in the Upper Cretaceous deposits of the Gui~ region. Some authors have preferred to mclude all of them under Morton's species, hut i~ so doing they were obliged lo allow a wider range of variation than seem_s nece~sary, in view of the fairly consistent differences recorrnizable in col· lections from different horizons and local· ities. One of the varietal forms is the shell from Coon Creek, Tennessee described by \Vade:! 1 u under the name ' Crassatellites :!!:·Morton, S. G., Synops:!I of the organic remains of the Cretaceous group of the United States, p. 66, pl. 13, f.g, 12. 18.ll. " 1'1W I B -a<<'. ruce, U. S. Gl'OI. Survey Prof. Paper 137, pp. 79-80, pl. 25, fi~!<. 6-8, 1926. Invertebrate Fossils of the Navarro Gr.oup tltltlosw (Morton) , and for which I here propose the name Crassatella vadosa wadei, designating the shell shown in Wade's monograph on plate 25, figures 7 and 8, as holotype. This subspecies is higher and flatter, and has the beak more distantly removed from the anterior ex­tremity than the typical form of the species. Another subspecies is the one from Owl Creek, Mississippi, named by Conrad217 CrtU&atella ripleyana. This form appears to he slightly shorter, more ventricose, has a more prominent umbonal projection, and narrows down to a more pointed posterior extremity than the typical form of the species, but is nevertheless very close to it; it might be treated as a variety under the name Cra.ssatella vadosa ripleyana (Conrad). The shells from the Monmouth forma­tion of Maryland, referred by Gardner218 to CTGJ&atellites vadosits (Morton), are clOle to the l ypical form of the species, but the umbonal ridge appears to be less angular and the posterodorsal slopes more Wflated, so that with perfect material for comparison they, too, might perhaps be appropriately classed as belonging to a aubspecies. Fout varietal forms are rec­ogni.Jed in Texas. CRASSATELLA VADOSA MANORENSIS Stephenson, n.var. Pl. 29, figs. 6-9 Individuals of this subspecies are especially numerous at several localities in the Kemp clay in Travis County. Shell large, subtrigonal in outline, equivalve, inequ.ilateral, moderate} y convex, with KRatest inflation about midway of the wnbonal ridge. Shell wall thick. 'Ombonal ridge obtusely subangular, ex­tending to the lower posterior extremity. The individuals exhibit some variation in outline, but in general the shells are char­aeterized by their short and stubby a p­pearance and their moderate inflation. Beaks moderately prominent, incurved, •Conrad, T. A., Acad. Nat. Sci. Philadelphia JQur., 2d ..... TOI. 3, p. 327. pl. 35, 61. 3, 1858. taacudner, Julia A.. Maryland Geol. Survey, Upper c.tao.ou1 (2 voll.), p. 649, pl. 39. 6p. 1-4, 1916. prosogyrate, approximate, situated well in advance of the midlength. Hinge of right valve with one strong cardinal tooth di­rected downward and a little backward and hearing striae on the sides; back of this is the resilifer of rather broad tri· angular shape and extending only about halfway down across the hinge plate; below the resilifer is a sunken platform which receives a bent cardinal of the left valve; a weakly developed anterior cardinal is separated from the sub­umbonal cardinal by a deep triangular socket of moderate depth. On the hinge of the left valve a deep triangular socket separates a strong anterior cardinal from a weaker subumbonal cardinal; the latter is most prominent below, where it curves around below the short triangular resilifer. On the right valve there is a long dull­crested posterior lateral marginal ridge which fits into a corresponding channel on the margin of the left valve, and seems to function as a lateral tooth. Lunule dis­tinct and deep, most sharply outlined on the left valve. Escutcheon fairly distinct, only moderately deep, most clearly de­fined on the right valve. Adductor scars small, ovate in outline, subequal, strongly impressed; back of the upper end of the anterior adductor scar is a small, deeply impressed pedal scar, and immediately above the posterior adductor is another similar small scar. Pallial line simple. Margin finely crenulated. Anterior mar­gin regularly rounded; ventral margin broadly rounded, becoming nearly straight posteriorly; posterior margin subangular below, truncated above, rounding into the posterodorsal margin. Surface marked by rather coarse growth lines and ridges of irregular strength. Dimensions of the holotype: Length 45 mm., height 38 mm., thickness 27 mm. This variety is less pointed posteriorly, and the radial sulcus in front of the umbonal ridge is much weaker than on the typical form of the species. Compared with other subspecies it is much shorter than chat fieldensis; it is shorter and more inflated than bexarensis; it is broader, less inflated, and much less pointed posteriorly than ripleyana; wadei is a flatter and much longer form. The University of Texas Publication No. 4101 Trpes.-Holotype, U.S.N.~. no. 76544; figured paratype, U .S.N .M. no. 76545; ] 2 unfi.gured paratypes, U.S.N.M. no. 765-t.6. Distribution in Texas.-Navarro group, Corsicana marl; ?2 3/ 5 miles north by ea~t of i\Ialta (5310, 12934); ?about 5 miles east bY north of Greenville (12924) ; 1 ~) mile beiow Martindale (15526) ; 2V2 ll;i les west of McQueeney ( 15523) ; well, 7 · 20 mile southwest of St. Mary's Uni­Yersity Bexar County (16408). Na~·~1-ro group, Kemp clay: 3 miles northwest of Lockhart (Tex. Bu. 1174); 11.1.) miles northwest of Texas Hill (] S533) : ? at Webberville (7601) ; near Deatsvill~ (764, 14125) ; 2 miles north­west of Deatsville (14128) : 2Vt miles north bv west of Deatsville (16146) ; :-F/1 mil~s southeast of Manor (16142); 31l> miles east of Manor (14158, 15534); 3~{ miles east by north of Manor (13861, holotype and 13 unfigured paratypes) ; 2 2 /S miles southeast of Manor (18196) ; 4 n~iles south of Manor (Tex. Bu. 2399) ; 5 miles west bv north of Elgin (14162); branch 6Y1 n;iles southwest of Currie (14139, 1 figured paratype) ; 41/~ miles northeast of Roane (12921) . Range.-Rare in Corsicana marl and common in Kemp clay of Navarro group. CRASSATELLA VAOOSA CHATFIELDENSIS Stephenson, n.var. Pl. 29, fig~. 10, 11 This subspecies is represented by one large, well preserved shell from near Chatfield~ but younger and imperfectly preserved specimens from several other localities are also referred to it. Com­pared with the typical C. vadosa Morton, it is larger. proportionately higher, is plumper anteriorly, and the umbones are more prominent and a little farther re­moYed from the anterior extremity; the umbonal ridi!e is less angular, and the posterudorsal slope not so steep. Dimensions of the holotype: Length 56 mm.. hPip:ht 46 mm., thickness 31.5 mm. Holotype.--FS.~.M. no. 765-17. Distribution in Texas.-Navarro group, :\acato('h sand: 3 '5 to --1/) mile north­east of Chalfield ( U 11 7~ type lo c. ) ; near Kaufman (761) ; 3 miles north of Sulphur Bluff (5322); Pl2 miles west of Commerce (5323) . CRASSATELLA VADOSA BEXARENS~ Stephenson, n.var. Pl. 29, fi~s. 1-5 Great numbers of the shells of this sub. species occur in a good st~te of ~reserva­tion, in concretions in gullies which enter Cibolo Creek from the Bexar County side, 11/2 miles west of Zuehl, Guadalupe County. They exhibit great individ~al variation in outline, but compared with the typical form of the species they are all flatter, have less prominent and less anO"ular umbonal ridges, and in general th; beaks are somewhat more distantly removed from the anterior extremity. This sub~pecies is flatter than the subspecies chat~eldensis, and is more elongated and less· inflated than manorensis. Compared with the eastern Gulf subspecies it is flatter and much less pointed posteriorly than ripleyana and is a little more in· flated and in general less elongated than 1radei. Dimensions of the holotype, an adult riaht valve of about average outline: e . Length 53 mm., height 43 mm., convexity 15 mm. The right valve shown in plate 29, figure 4, which represents an extreme development of the height with respect to the leni!th, is 57 mm. long and 50 mm. high. The left valve shown in plate 29, figure 1, which represents an extreme development of length with respect to height, is 4.9.5 mm. long, and 38 mm. high. Types.-Holotype, U.S.N.M. no. 76548; 3 figured paratypes, U.S.N.M. no. 76549; 23 selected unfigured paratypes, U.S.N.M. no. 76550. Distri'.bution in Texas.-Navarro group, Kemp clay: West of Zuehl (7085, 7720; 7721, type lot) ; branch 6% miles south· west of Currie (17377) ; road 31h miles north-northwest of Bazette (17375) ; 3% miles north-northwest of Bazette (17376). CRASSATELLA VADOSA CEDARENSIB Stephenson, n.var. Pl. 27, fig. 12 This variety is represented by four specimens from three localities. The holo· type is not full grown but is well pre· served. Compared with the typical C. Invertebrate Fossils of the Navarro Group vadosa the holotype is proportionately flatter, higher, and shorter, and is more conspicuously arched on the posterodorsal margin. It is higher and more arched on the posterodorsal margin than any of the varieties of vadosa here recognized. Dimensions of the holotype: Length 32.6 mm., height 28.2 mm., convexity 8 mm. Types.-Holotype, U.S.N.M. no. 76551; 1 paratype, U.S.N.M. no. 76552. Distribution in Texas.-Navarro group, Neylandville marl: 21;2 miles due north of Corbet (16170, type lo~.); ?from 5 miles northwest of Terrell (14104) ; 7 1/10 miles northeast of Cooper (14083). CRASSATELLA QUINLANENSIS Stephenson, n.sp. Pl. 27, figs. 9-11; pl. 28 Shell relatively small, depressed convex, elongate, subtrigonal, equivalve, inequi­lateral, n a r r o w i n g to a subpoint posteriorly. Umbonal ridge weakly de­veloped, rounded on the crest. Beaks nonprominent, flattish, slightly incurved, nearly direct, slightly separated, situated about 0.3 the length of the shell from the anterior extremity. Hinge of right valve with two cardinal teeth, a posterior prominent one in front of the resilifer extending obliquely downward and for­ward, and a weak anterior one almost marginal; the two are separated by a narrow deep socket; along the posterior flank of the posterior cardinal, closely bordering the resilifer, is a shallow socket for the reception of the posterior cardinal of the left valve; the resilifer is wide, triangular, broadly excavated, and extends to the inner margin of the hinge plate; a short, weak groove bordering the antero­dorsal margin receives the sharp antero­dorsal margin of the left valve; the posterodorsal margin bordering the escutcheon is a straight, sharp carina. Hinge of left valYe with a prominent, thin, nearly vertical posterior cardinal in front of the resilifer, and a long, prom­inent, oblique anterior cardinal; between the cardinals is a deep socket of moderate width, and in front of the anterior cardinal is a narrow, shallow socket; the antero­dorsal margin 1s a prominent sharp carina, and bordering the posterodorsal margin is a long, narrow groove which receives the sharp posterodorsal carina of the right valve; the inner edge of this groove forms a weakly developed lateral tooth. Except on the surfaces facing the resilifer the sides of the cardinal teeth are scored approximately at right angles t.o the plane of contact of the two valves. Adductor scars of medium size, subovate in outline, the anterior one elongated nearly vertically, and the posterior one nearly horizontal. Inner margin finely crenulated. Lunule excavated, distinctly outlined; escutcheon excavated, sharply outlined, extending a little less than half­way to the terminus of the shell. The anterior margin is rather sharply rounded; ventral margin broadly rounded; posterior extremity sub pointed; posterodorsal mar­gin long, nearly straight, gently descend­ing. Surface marked by medium to fine growth lines and undulations. On a young, uncorroded individual (pl. 27, fig. 11) numerous concentric ridges are strongly developed in the umbonal region. Dimensions of the holotype, a right valve: Length 38 mm., height 22 mm., convexity 6.5 mm. This .species is a close analogue of Crassatella pteropsis Conrad219 (not C. pteropsis Gabb), from the Ripley forma­tion, Tippah County, Mississippi. The Texas species differs in that it is less pointed posteriorly, has a less clearly marked umbonal ridge, lacks a broad radial sulcus in front of the umbonal ridge, and is more plumply filled out in the region of the posterodorsal slope. Types.-Holotype, U.S.N.M. no. 76553; 1 figured paratype, U.S.N.M. no. 76554; 13 unfigured paratypes, U.S.N.M. no. 76555; 20 + paratypes, U.S.N.M. no. 76556 (on large slab, pl. 28, fig. 4) . Distribution in Texas.--Navarro group, N acatoch sand: 14~ miles northeast of Quinlan (16162, 16171, type lots). Unidentified specimens of CRASSATELLA Poorly preserved shells and internal and external molds of Crassatella in the collections are mentioned below. 219Conrad , T. A., Acad. Nat. Sci. Philadelphia Jour., 2d ser., vol. 4, p. 279, pl. 46, fig. 9. An indeterminate internal mold of a small specimen of Crassatella was found in the Corsicana marl in a road ditch 1.8 miles N. 20° w·. of Tona siding, in Hunt County (15545). U.S.N.M. no. 76557. In two collections from the same forma­tion in the left bank of San Marcos River, 1/ 2 mile below Martindale, Caldwell County (7621, 15527), are several speci­mens of a small Crassatella (a), about as long as high, subtrigonal in outline, and depressed convex; the anterior margin is sharply rounded, the ventral margin broadly rounded, and the posterior mar­gin obtusely subangular below and sub­truncated above; the surface is orna­mented with rather coarse, somewhat ir­regularly developed concentric lines, coarsest toward the margin. The umbonal ridge is weakly developed. One specimen from collection 7621 figured (pl. 29, fig. 13), U.S.N.M. no. 76558; unfigured specimen (15527), U.S.N.M. no. 76559. Another small species of Crassatella (b) from the 5ame locality (7621, 15527) is represented by 6 poorly preserved speci­mens, 4 left and 2 right valves (pl. 29, fig. 12) ; it is an elongated, ventricose, rather coarsely sculptured species with a strongly developed, subangular umbonal rjdge, bordered in front by a broad, shal­low radial sulcation, and with a squarely truncated, nearly vertical terminal margin. The dimensions of the figured left valve are: Length about 10 mm., height 8 mm., convexity about 2 mm. One specimen from collection 15527 figured (pl. 29, fig. 12), U.S.N.M. no. 7656 L; unfigured specimens, lJ.S.N.M. nos. 76560, 76562. Specifically indeterminable molds of Crassatella were obtained from the Cor­sicana marl at the lower crossing of Medina Rin?r at Castroville, Medina County (7796, U.S.N.M. no. 76563); on the Castroville road, 6 miles east of Castrovi lie in Bexar County (15502, C.S.N.M. no. 76564); at pit of Standard Fuller's Earth Co., '1/ 3 mile north of Castroville road, about 14 miles west of San Antonio, Bexar County (15520, C.S.A.M. no. 76565) ; and at a depth of ] 045 feet in well of Witherspoon Oil Company, Redus No. 1, G. A. Harper 92­acre Survey, Medina County ( 13844, U .S.N .M. no. 76566) . These probably belong to C. vadosa Morton or one or more of its varieties. An internal mold of a rather small left valve of Crassatella, with a film of shell material still adhering, was found in the Kemp clay in a bluff on a .small branch enterinrr York Creek, 4 miles southeast of Zo~, Guadalupe County (10877). The specimen is flattish, is high in propor­tion to its length, has a weak umbonal ridae and the posterodorsal margin is high ' and rounds broadly into the sub. truncated posterior margin. U.S.N.M. no. 76567. Genus UDDENIA Stephenson, n.gen. 1875. Crassatellites Conrad (interpreted as a young individual), Geol. Survey North Carolina Rept., vol. 1 (by W. C. Kerr), App. A, p. 6, pl. 1, fig. 25. 1885. Gouldia Whitfield, U.S.Geol. Survey Mon., vol. 9, p. 125, pl. 18, figs. 1-3. (Geol. Survey New Jersey, Paleontology, vol. 1, p. 125, pl. 18, figs. 1-3, 1886.) 1905. Eriphyla Johnson, Ac.ad. Nat. Sci. Phila· delphia Proc., vol. 57, p. 14. 1907. Eriphyla Weller, Geol. Survey New Jersey, Paleontology, vol. 4, p. 550, pl. 60, figs. 4-8. 1923. Crassatellites ? Stephenson, North Carolina Geol. and Econ. Survey, vol. 5, pt. 1, p. 274, pl. 67, figs. 10-16. Type species.-Gouldia conradi Whitfield. (Types in Acad. Nat. Sci. Philadelphia.) This tiny member of the Crassatellidae has heretofore been referred by different authors to Crassatellites, Gouldia, and Eriphyla (of the Astartidae), though it obviously forms a group different from any of these genera. It is apparently nearest to Crassatella, from which it dif· fers in its diminutive size, its shorter and higher outline, its straight, long, steeply descending dorsal margins, its relatively long, narrow lateral teeth and sockets, and the high position of its adductor scars. The hinge of the left valve, as shown by specimens identified as U ddenia conradi (Whitfield), from Snow Hill, North Caro· lina, includes: An obscurely developed anterior cardinal tooth attached to the upper end of the long, marginal, anterior pseudolateral tooth; a profound, trigonal socket; a cardinal tooth below the beak, which is weak above, but which expands prominently below and becomes elongated backward along the lower margin of the Invertebrate Fossils of the Navarro Gr.oup 1ainp plate; a rather -deep, small carti­lage pit back of the upper end of the cardinal tooth just described; a long, narrow, marginal, anterior pseudolateral tooth which fits into claspers on the right valve; and a pair of long, posterior lat­eral claspers which include a thin, promi­nent marginal carina above and a thin tooth below, separated by a deep, nar­row sooket. The right valve presents: A prominent cardinal tooth which is thin above, be­coming thick below in adults, and which fits into the deep socket in the left valve; back of this cardinal tooth a broad, tri­angular cartilage pit along the forward aide of which is an open slit; the margin of the pit below overhangs a more deeply inset bench into which fits the prominent, elongated cardinal tooth of the left valve; in front of the cardinal tooth a narrow, oblique socket; a pair of elon­gated, anterior lateral claspers for the accommodation of the anterior marginal lateral of the left valve; a narrow, mar­ginal, posterior pseudolateral which fits into the posterior lateral claspers of the left valve. The pallial line is simple and the adductor scars are small and high in the shell. The long lateral dentition extends past the adductors both front and rear. The genus is named in honor of the late Dr. J. A. Udden, of Austin, Texas. UDDENIA TEXANA Stephenson, n.sp. Pl. 26, figs. 1--3 Shell small, trigonal in outline, de­premed-convex, equivalve, slightly inequi­lateral. Beaks small, incurved, approxi­mate, nearly direct. Greatest inflation central, above the midheight. There is a mere suggestion of an umhonal ridge, between which and the posterodorsal margin is a shallow radial sulcus extend­ing to the posterior margin. Lunule long, Darrow, sharply outlined, moderately eacavated. Escutcheon long, narrow, more sharply outlined, and more deeply exca­vated than the lunule. The dorsal mar­gins descend in nearly straight lines from the beak at an angle to each other of about 95 degrees; the ventral margin is evenly and broadly rounded ascending lteeply both toward the front and rear; posterior margin truncated below the mid­height. Surface marked by fine, rather sharp, closely spaced incremental lines. Dimensions: Length 3.9 mm., height 3.7 mm., thickness about 1.8 mm. The species is somewhat more plump, is shorter and more trigonal in outline, and is more finely and more regularly sculptured than Uddenia conradi (Whit­field) , the type species of the genus. Type.-Holotype, U.S.N.M. no. 76568. Distribution in Texas.-Navarro group, N acatoch sand: North edge of Corsicana (518). UDDENIA sp. Fragmentary material from the Kemp clay exposed on Colorado River at Web­berville, Travis County (7601), furnishes the basis for the following description: Shell small, trigonal in outline, moder­ately ventricose. The beak is small, slightly prominent, narrow, incurved, and nearly direct. The hinge appears to be essentially like that of typical shells of the genus from Snow Hill, North Caro­lina. The other internal features are also like the typical specimens. The inner sur­f ace is beautifully polished. The antero­and posterodorsal margins are straight and descend with moderate steepness from the beak. The anterior, ventral and posterior margins present a nearly uni­£orm curvature, with a mere suggestion of a posterior truncation. The surface is nearly smooth with the exception of sev­eral small concentric wrinkles on the umhone. The largest shell is about 3 mm. long; a young incomplete right valve measures: Length 1.2 + mm., height about I + mm., convexity about 0.25 mm. The material probably represents an undescribed species that is smoother, relatively shorter, and much less dis­tinctly truncated than other described species. U.S.N.M. no. 76569. UDDENIA sp. One poorly preserved left valve of Uddema, from the Corsicana marl on San Marcos River, 1h mile below Martindale, Caldwell County ( 7621) , is more elon­gated than U. texana and exhibits sharp, regular, concentric sculpture (pl. 26, fig. 4.) It is also more coarsely sculptured The University of Texas Publication No. 4101 than U. conradi (Whitfield). U.S.N.M. no. 76570. Genus SCAMBULA Conrad 1869. Scam bu/a Conrad, Am . .lour. Conch., vol. 5. p. -18, pl. 9, figs. 7, 8. 1872. Scambula Conrad, Acad. Nat. Sci. Phila­delphia Proc., ml. 2-1, p. 51. pl. 1, fig. 2. 1885. Scamlmla perplana Conrad. Whitfield. U.S. Geol. Survey l\lon., vol. 9, p. 121. (Geol. Survey Ne~ Jersey, Paleontology, vol. l, p. 121, 1886.) Discusses the genus under the species heading. Type species.-Scambula perplana Conrad, from the Woodbury clay, Haddonfield, New Jersey. Although this genus differs consider­ably in form and proportions from Crassatella, it appears to be more closely allied to that genus than to the Gouldiidae in which Stewart2::! 0 places it. Its form is compressed, it has a broadly concave posterodorsal margin, and the submerged ligament occupies a long, narrow, curved resilifer instead of a broad, triangular one. Conrad's original description of the genus is as follows: "Hinge with two approximate teeth in right valve, the pos­terior one direct and ending at the apex; a long anterior double tooth parallel with the straight cardinal line; anterior muscular impression small, rounded." Gabh:.!:.!i compared the types of Scam­bula Conrad with those of Anthonya Gabb, and considered the former as synonymous with the latter. He says, "On comparing my types of Antlwnya cultriformis, with those of Mr. Conrad's Scambula perplana, it proves that they are generically iden­tical, the hinges agreeing perfectly. There is only one difference, and that of minor importance; my shell, which is very long, is slightly twisted, while Mr. Conrad's, which is much shorter, is all on one plane." Gabb's genus was found in the Chico, a California formation as old as the Turonian or the Cenomanian, and his genus therefore occupied a considerably lower stratigraphic position than Conrad's ~1Slt'wart, Ralph. :\cad. :\at. ~ci. Ph"J;1Jelphia Special l'ub. :'lio. 3, p. 119, 1930. ~IG:ibb. W. '\f., :\cad. :'\at. Sci. P!1ila l1·lphia Proc., yo!. 28, p. 311, 1876. O'enus from the Woodbury clay, which b " • I h lwlongs well up in the ~enoman. ~ ere. fore hesitate to treat these geographically and stratiO'raphically widely separated forms as b rrenericall y identical without t'l • having had an opportumty to compare the types. Stewart:!:!:! regards Scambula as of subgeneric rank under Anthonya, but he states that the hinge of the latter is not well known. Wade's223 collection from Coon Creek, Tennessee, contains two left valves, which he referred to Sca1nbula per plana Con­rad; both of the hinges are well pre· served, and show two well developed, long, slightly curved, nearly vertical car· dinal teeth, separated by a deep socket whose sides are striated normal to the plane of juncture of the two valves; the anterior cardinal is thicker than the pos­terior one, and is also crenulated on its anterior side. Back of the slender, pos­terior cardinal is a long, deeply exca· vated, slightly curved resilifer which is a little wider than the socket just de· scribed. A long, thick posterior lateral tooth extends in a broad curve concave outward, from the beak past the resilifer, along the inner margin of the hinge plate, nearly to the rear end of the pos· terior adductor scar; this lateral is sepa· rated from a long, narrow, marginal carina by a long, narrow, deep channel, the tooth and the carina forming a pair of claspers. There is also a slightly thicker marginal carina extending from the beak nearly to the front end of the anterior adductor scar. The types of Scambula perplana Con· rad in the Academy of Natural Sciences of Philadelphia include 5 well preserved shells, 3 left and 2 right valves. The hinge of the left valve agrees closely with those of the left valves from Coon Creek, Tennessee; the right valve has a resilifer opposite that of the left valve, a pair of long anterior claspers for the reception of the marginal carina of the left valve, and a long, thin posterior marginal carina fits into the claspers of the left valve. !:?!!:?Stewart, Ralph. np. cit., pp. 148-H9. 221\Cidc, Bruce, U. S. G1·01. Survey Prof. Paper 137, p. 82, pl. 25, figs. 11, 12, 15, 16, 1926. Invertebrate Fossils of the Navarro Group Tertiary shells which Dal12H referred to Boambula, and treated as a section under . c~~llite&, cannot properly be so clas­sified. In this connection Woodring225 says: "The name Scambula was proposed by · Conrad for an Upper Cretaceous species, S. perpldna Conrad, from New Jersey. This species has also been found in Upper Cretaceous deposits in Georgia and Ten­nessee. It is very small, unusually flat, has a different hinge, and in general fea­tures resembles Crassinella. The name Scambula can be used only for this ~iar Upper Cretaceous shell. The dilrerence between the Bowden species, which belong to the group that has been called Scambula, and the type of Crassa­tellila, hardly warrants a new section name." SCAMBULA PERPLANA Conrad Pl. 26, figs. 11, 12 1869.. Scambula perplana Conrad, Am. Jour. Conch., vol. 5, p. 48, pl. 9, figs. 7, 8. 1872. Scambula perplana Conrad, Acad. Nat. Sci. Philadelphia Proc., vol. 24, p. 51, pl. 1, fig. 2. 1685. Scambula perplana Conrad. Whitfield, U. S.GeoL Survey Mon., vol. 9, p. 123, pl. 18, figs. 8-10. (Geol. Survey New Jersey, Paleontology, vol. 1, p. 123, pl. 18, figs. ~10, 1886.) . 1985. CrauateUites (Scambrda) perplana (Con­rad). Johnson, Acad.. Nat. Sci. Phila­delphia Proc., vol. 57, p. 14. 1907~ Scambula perplana Conrad.. Weller, Geol. Survey New Jersey, Paleontology, vol. 4, p. 562, pl. 61, figs. 13, 14. 1926. Scambula perplana Conrad. Wade, U.S. GeoL Survey Prof. Paper 137, p. 82, pl. 25, figs. 11, 12, 15, 16. This genus is represented in the Corsi­cana marl by several imperfect specimens embedded in marl, with the shell suh­atanee partly dissolved away, only a film mnaining; the hinge of a left valve is fairly well shown on one specimen, and lppears to be identical with that of the tfPes in the Academy of Natural Sciences al Philadelphia and with perfect shells ""8cribed by Bruce Wade from Coon Cnek, Tennessee. Shell small, thin, elon­gate, equivalve, inequilateral, almost flat. -0.U. W. H•• Wagner Free Inst. Sci. Trana., vol. 3, •t. "pp. 1'67-1475, 1903. . ....oedrins, W. P., Carnepe Imt. Washington Pub. .... p. M, 1925. Beak flat, angular and prominent verti­cally, slightly opisthogyrate, situated about two-fifths the length of the sh el 1 from the anterior extremity. Antero­dorsal margin nearly straight, hut slightly arched near the beak, moderately in­clined; anterior extremity subrectangular; ventral margin broadly convex, straight­ening out a little posteriorly; posterior margin truncated, slightly inclined for­ward toward the upper margin; postero­dorsal margin rather strongly concave, especially toward the beak. The surface is smooth except for fine incremental lines which become a little coarser toward the antero· and posterodorsal margins, and ap­parently also toward the beak. Dimensions of the specimen shown in plate 26, figure 12: Length 14 mm., height 9.7 mm. No other species of Scambula has been recorded from the American Cretaceous. Types.-Three left valves and two right valves in the Academy of Natural Sciences of Philadelphia, from the Woodbury clay, Haddonfield, New Jersey. Two plesio­types from Texas, U.S.N.M. nos. 76571, 76572. Distribution in Texas.-Navarro group, Corsicana marl: 1h mile below Martin­dale (7621, 15527, 1 specimen figured from each lot) . OutsiJe distribution.-Tennessee: Coon Creek tongue of Ripley formation. Mississippi: Owl Creek formation. Chattahoochee region (Alabama and Georgia) : Upper part of Ripley formation. New Jersey: Woodbury clay and Weno­nah sand. Range.-Corsicana marl of the Navarro group of Texas, and the zones of Exogyra ponderosa and E. costata in the Atlantic and eastern Gulf Coastal Plain. Superfamily CHAMACEA Family MONOPLEURIDAE Genus TITANOSARCOLITES Trechmann Type species.-Caprinula gi,gantea Whitfield.226 The genus Titanosarcolites Trech­~n227 was erected to include those large, !IOWhit6eld, R. P.. Bull • . Amer. Mus. Nat. History, TOI. 9, art. 12, pp. 194-196, pis. 18-22, 1897. DlTrechmann, C. T., Ceol. Mag., vol. 61, pp. 397-400, pl. 23, 6p. 1, 2; text fig. l, 1924. See also Cox, L. R., Geol. Assoc. London Proc., vol. 44, pp. 379-388, 1933. The University of Texas Publication No. 4101 thick-shelled. subequiYal\'e rudistids, each Yah-e of which is traYersed by a compara­tively small longitudinal septate body cavitv and each valve of which has a thick. outer shell laver tr:iversed by a series of relatively lar.ge tubes of irregular size and distribution and circular, oval, and irre!!ular cross section; the tubular layer is'-developed around the antero­ventral side. The two valves are curved in one plane with the tips turned toward each other. This large cumbersome bi­valve is interpreted not to have been at­tached at the beak of either valve but to have lain recumbent on the sea bottom on the anteroventral side. A detailed description of the genus, with especial reference to Cuban material, is given by Mac Gillavry.228 Both Douville~29 and Mac Gillavry as­sign to the genus a monopleurid rather than a caprid or radiolitid ancestry, a con­clusion based on the arrangement of the cardinal apparatus. Mac Gillavry points out the relation of this apparatus to that of such genera as Antillocaprina, Trech­mannella, Hippurites, and Rousselia, to all of which he ascribes a monopleurid origin. Neither the cardinal apparatus nor the dentition are preserved in Titanosarcolites uddsensis, and its reference to this genus is based on the similarity of such of its features as the longitudinal septate cavity, the longitudinal canals, and the series of large longitudinal tubes in the outer part of the shell on the anteroventral side. That this Texas shell is specifically different from T. giganteus is indicated by the smaller size of the septate cavity, the more sharply defined perimeter of this cavity~ the much larger size of the longi­ tudinal canals, and the larger average size of the longitudinal tubes. In addition to the Texas specimens herein described, fragmentary material that may belong to Titanosarcolites has been recorded from the Upper Cretaceous :?ZS\fac GillaHy. Henry Jame~. Geolo~y of the Province of Camaiway, Cuba. with rcvisional studies in rudist paleontology: Dissertation, l'ni\", l"trecht, l93i, pp. 85.92, pl. 2, fi{: ~. 1-7, 10. 11; pl. 3, fiJ,!. 3; pl. 9, fig. 1, 1937. ::?:!'•.lDou\'illc, H., S<,c. ;.:~·ol. France Bull.. 1e !H'r., tome 26, pp. 131-133. pl. 8. fq::. 5, 1<>2i. of the l T nited States under the names lchthyosa.rcolites Desmarest and Cap­rinella n·orbi~ny. However, none of these spe('imens has shown in the parts preserved any evidf'nce of the presence of the thick outer shell layer traversed by larrre lonrritudinal tubes, such as char- b C' acterizes Titanosarcolites. Tuomey2:rn described three species of so-called lclzthyosarcolites from Noxubee County, Mississippi, which may have been representatives of Titanosarcolites, but he did not illustrate his material, his de­scriptions are inadequate, and his types are lost. In the collection of the National Museum is a cast of the internal septate cavity of a Titanosarcolites? (U.S.N.M. no. i2689) from Alabama, which F. B. Meek identified as belonging to "lchthyo· sarcolites cornutus," one of the three species described by Tuomey. Hall and Meek~:H described one valve of a rudistid shell from Sage Creek, Nebraska, from the upper part of division No. 4 ( =upper part of Pierre shale), under the name Caprinella coraloidea; it may be a Titanosarcolites. The descrip· tion and :figures indicate a short conical, somewhat spirally twisted shell about 2.5 inches long, having an internal cavity di· vided into chambers by lamellae or septa convex toward the apex, spaced at inter· vals of 1 to 4 millimeters; the chambers are fl lled with matrix or secondary calcite. The shell is composed of numerous four· to six-sided longitudinal canals whose hollow interiors are interrupted at irreg· ular intervals by thin transverse laminae. According to J. B. Reeside, Jr.,232 shell fragments of this character have subse· quently been found at several localities in Wade233 the Pierre shale. identified a small fragment from Coon Creek, Mc· 1\airy County, Tennessee, as belonging questionably to Hall and Meek's species. 230Tuc 101ey, ~I.. Acad. :'\at. Sci. Philadelphia Proc., vol. 7, p. 172, 1851. Z11Hall, James, and :'\1c1·k, F. B .. Amer. Acad. Arts Sci. Mem., n. scr., vol. 5, pp. 380-381, pl. 1, figs. 3a·f, 1856. 23ZOral communication. z33\\·ade, Bruce, U. S. Geol. Survey Prof. Paper 137, p. 82. pl. ::?5, figs. 13, U , 1926. Invertebrate Fossils of the Navarro Gr.oup TITANOSARCOLITES ODDSENSIS Stephenson Pl. 30; pl. 31 ; pl. 32, fig. 1 1938. Titanosarcolites odthensis Stephenson, U.S. GeoL Survey Prof. Paper 193-A, p. 3, pl. I ; pl. 2 ; pl. 3, fig. I. The holotype, a left valve, is incom­plete at both ends, and the outer surface is badly damaged and largely destroyed by corrosion. Scattered about over the surface are the incomplete attached por­tions of small irregular oysters of unde­termined species. The adult shell is large, very thick, co~ular, rather strongly curved, traversed longitudinally by a proportionately small acentric tubular septate body cavity. The poorly preserved outer surface of the shell appears to be longitudinally ribbed, the ribi probably being of only moderate strength. The body cavity is markedly acentric in position as shown by the cross aections; it lies 10 to 20 mm. within the shell a little to one side of the plane of maximum curvature of the cone. The side of the cavity has been partly crushed in mechanically, the pressure having been applied from the thinnest side of the sur­rounding shell; as a result the thin septa have been broken and the fragments seg­regated in parts of the cavity (see pl. 32, fig. 1) . Before the crushing took place the cavity was probably subovate in cross aection and had a maximum diameter of about 32 millimeters. The maximum measurable thickness of the shell surrounding the septate cavity is 109 millimeters. Radially outward from the cavity the shell is divisible into three layers or hands of unequal thickness. The inner layer is I millimeter or less in thickness and forms a well-defined lin­j.ng or boundary to the cavity; it is lamellar in structure, the lamellae lying parallel to the inner surface of the cavity; the septa, which are also lamellate, pro­trude inward across the cavity from this layer, and are concave toward the larger end of the shell. The intermediate laver ha a maximum measured thickness " of about 52 mm. and is composed of two kinds of canals. The main body of the layer is made up of longitudinal four-to six-aided thin-walled, chambered canals measuring in cross section as much as 2.5 mm. and showing no serial arrangement in any direction. The transverse laminae dividing these canals into chambers are irregularly spaced, the spaces ranging from 0.5 to 2.5 mm.; the laminae are con­cave toward the larger end of the shell. As shown in the polished cross section of the shell a subordinate part of the inter­mediate layer is composed of tabular or "stretched" canals, which are subdivided into rectangular spaces by much thinner transverse longitudinal walls. These tabular canals are arranged in three sepa­rate longitudinal groups whose cross sec­tions are seen in the illustrations; a large, sharply outlined group, elongated lens· shaped in cross section, lies to the right of the septate cavity, the lower end almost touching the inner shell-layer, and the other end I ying upward to the right of and obliquely away from the septate cav­ity; a second smaller more irregularly shaped group lies above and well away from the first group; a third group, seen only in the smaller cross section, is badly crushed, but at the smaller broken end of the shell itself this group appears as a large, broad, well-defined patch similar to, but less elongated than, the first group described. These groups of tabular canals mark the areas of muscular attachment dur­ing the successive stages of shell growth; the large crushed area to the left of the septate cavity in plate 3, figure 1, is interpreted to mark the position of the posterior myophore (mp) and the one to the right the anterior myophore (ma}. The outside shell layer has a maximum measured thickness of 79 millimeters, and the cross section cut near the large incom .. plete end shows that the thickness of this layer does not fall below 50 mm. in an incompletely preserved band extending around the anteroventral side of the shell. This layer is traversed longitudinally by many tubular cavities ranging in cross section from less than 2 mm. to a measured maximum of 39 mm. The cavities have a heterogeneous arrangement and range in cross section from subcircular to ovate; some are irregular. The cavities are filled with fine brown calcareous silt matrix. They are separated from each The Unfrersity of Texa.s Publication No. 4101 other by proportionately thin walls of shell substance~ the better preserved parts of which are seC'n to he canaliculate like the intermediate shell layer already described. Howewr, the st~ucture has been partly destroyed or obscured ap~ar­enth-by the recn-stallization of the calcite. and. n;uch of the layer is stained with limonite and therefore appears dark in the photographs. Each cavity is lined with a calritic layer generally less than a quarter of a millimeter thick. The dental apparatus is not presern·d in the holotype, and there is no indication of the position of the ligament. The rrreatest dimension of the incom­plete h~lotype, measured in the longi­tudinal direction. is about 250 mm.: the minimum and maximum dimensions of the largest cross section are respectively 152 and 208 mm.: the smaller broken end of the specimen has minimum and maximum diameters of approximately 10-1. and 112 mm. A smaller mechanically flattened specimen, incomplete at both ends, from the type locality, probably belongs to the same species and is listed as a paratype. It is 140 mm. long; in its crushed con­dition it increases from about 75 mm. in maximum diameter at the small end to 92 mm. at the large end. The shell struc­ture has been destroyed by recrystalliza­tion of the calcite. Two fragments from a concretion in the same formation at another locality in Falls County proh­ably helon~ to this species. TJpes.-Holotype. U.S.N.1\1. no. 75979; 1 paratype~ r.S.N.M. no. 75980. Distribution in Texas.-Navarro group, upper part of Kemp clay: Limonite­stained calcium carbonate conc:-retions in a field north of the 1\lcClanahan-Odds road l'll the southwe~tward-facing: slope of Big Creek vallPv. 1 mile wC'st ll\ ~outh of Odds (Limeston~ County), in. Falls County (17373, type loc.); questionably in a field on the westward-£ acing slope of Big Creek rnlleY L~ miles ~outlwa~t of Par­~ons Bridµ-;, and :~ mil~~ .;;;.outhwest of Stranger~ Falls County (17372). Unidentified specimens of TITANOSARCOLITES? Specimens of Titanosarcolites? too in­complete for specific identification have been found at three localities in the Navarro group, as indicated below. ~n addition one small fragment was found m the upper part of th~ Taylor marl on St~te Highway 34, 5:y., miles northeast of Enms, Ellis County (17~)78). U.S.N.M. no. 76574. The most complete of the Navarro specimens was obtained in the Nacatoch sand on Postoak Creek at the north edge of Corsicana. NaYarro County (518, U.S.N.M. no. 20903). (See pl. 32, figs. 2-4.) This specimen indicates a short, rapidly expanding, strongly curved, slirrhtly spiral shell. Except near the apex only the part of the shell on the inner side of the curve is preserved; It Is pro· portionately very thick and is composed of lon!!itudinal prismatic canals of vary· inrr si;es of which most are four-to six· b ' sided but a few of the smaller ones may be circular or oval in cross section. The hollow interior of each of the canals is interrupted at irregular intervals by thin transverse uncurved laminae, the laminae in one canal bearing no uniform relation in position to those in adjoining canals; the canals in one group, shown just to the left of the internal cavity in plate 32, firrure 3, are smaller than the others. A p~rt of the external surface on the inner curve of the shell is nearly smooth but exhibits fine radial striations and six or seven light-colored radial lines above the beak. spaced at intervals of 2 to 4 mm. The septa that divide the inner cm·it,. of the shell into chambers are not .preserved, having apparently been lo~t bdore fossilization. This cavity ends apicall~· in a bluntly rounded bottom, cor­respondin~ rather closely in shape to the inner cavity shown in Hall and Meek's illustrations of Caprinella coraloidea (op. cit., pp. 380-331, pl. 1, figs. 3a-c). The specimen cannot be satisfactorily identified with the latter species. Dimen· sions: Length, measured from the beak along the curve of the internal cavity to the outer margin. about 70 mm.; maximum thickness of shell, about 28 mm. One large imperfect shell fragment from the Nacatoch sand, found on the Dallas highway :~<> mile west of Kaufman, Kaufman County (14098, U.S.N.M. no. 75981), is made up of polygonal prismatic Invertebrate Fossils of the Navarro Gr.oup canals like those of Titanosarcolites, ex­cept that the transverse septa in the longi­tudinal canals are not curved. (See pl. 33, fig. 10.) The shell is very thick and the canals, though of irregular size, are in gen­eral larger than those of the Corsicana specimen. The hollow canals are set off at longitudinal intervals of 0.5 to 2 mm. by thin transverse laminae, and the inter­vening spaces are filled with secondary calcite. The external tubular layer such as characterizes Titanosarcolites, if orig­inally present, is wanting in the specimen as preserved. Dimensions: Greatest diam­eter, 106 mm.; maximum thickness of shell, 65 mm. A small elongated, curved shell frag­ . ment was found in the Kemp clay in a creek hank on the east side of a road 3Jh miles north of Powell and 10 miles northeast of Corsicana, Navarro County (9556). The fragment is composed of irregular polygonal canals in which at longitudinal intervals of 0.5 to 1.5 mm. are thin, transverse, uncurved laminae. The structure is similar to that of Titano­111Tcolites. U.S.N.M. no. 76573. Superlamily RUDISTACEA Family RADIOLITIDAE Genus SAUVAGESIA Bayle Type species.-Sphaerulites lusitanicus Bayle. One species only, Sphaerulites lusitani­cua Bayle, was mentioned in connection with the original description of this genus,2H and that species must therefore ·be accepted as genotype by monotypy. Later Jlttempts by M. Choffat and others to shift the genotype to Radiolites nicaisei Coquand seem clearly to he in violation of the rules. The acceptance of Sauvagesia aa a valid genus depends on whether Sphaerulites lusitanicus Bayle is or is not a true Radiolites. Even granting the valid­ity of Sauvagesia there is still a question as to the correctness of referring the Texas species to it. •Domtle, H., Bull. Soc. Geol. de France, 3d aer•• tome lt, p. S98, 1886. (Genus credited to Bayle.) SAUVAGESIA? BILLI Stephenson, n.sp. Pl. 33, fig. I ; pl. 34, fig. 9; pl. 35, fig. 9; pl. 36, fig. 9 Lower valve large, thick-walled, elon­gated, tapering, gently curved, broadly ovate in cross section. Main shell com­posed of strongly undulating cellular growth laminae which lie roughly normal to the length of the shell ; the cell pat­tern is of medium coarseness, but the cells are exceedingly variable, ranging in size from very small to 1.5 mm. in diam­eter, and in form from 4-to 8-sided. The inner shell layer as preserved is less than a millimeter thick, is finely striated lon­gitudinally within and is composed of longitudinal cells running parallel to the inner surface. Ligamental ridge thin, prominent, standing fully 7 mm. out from the inner surface, and expanding on the crest to a flange about 3 mm. wide; the part of the ridge between the inner sur­face and the flange is about 1 mm. thick. The external surface of the shell is badly corroded so that the thin external or cortical layer is partly or wholly destroyed except on the sides and bot­toms of some of the intercostal depres­sions. The shell is coarse! y ornamented with 11 strong ribs of very unequal size. As most of the intercostal spaces and their steeply sloping sides are similarly ornamented with small riblets there is difficulty in determining the position of the siphonal bands. The anterior siphonal band (E) is probably the deep, moder­ately wide longitudinal depression which cuts the outer surface directly opposite the ligamental ridge; the bottom of this depression is rounded or U-shaped below near the small end, but becomes less rounded and more nearly V-shaped from below upward. The second depression to the right of the anterior band ( E) , (pl. 35, fig. 9), may be the posterior siphonal band (S); it is similar to the anterior band (E) , but is not quite so deep, and is round to sub-V-shaped on the bottom. The two strong ribs between the supposed siphonal bands are badly corroded on their crests; they are separated by a broad sub-V-shaped depression shallower than the si phonal bands, and slightly acentric in cross section. The 9 other main The Untucrsity of Texas Publication No. 4101 ribs may be briefly descrihed from left to right as follows: (I) A narrow, hirrh rib followed by a narrow, deepV-~haped depression; (2) a broad, n~od­erately high rib, steep on the left side, much less steep on the right, rendered bifid by a shallow, narrow crestal depres­sion which lies a little to the left of the center; (3) beyond the next interspace is a broad, prominent, but badly corr?ded rib. steeper on the left than the nght, and followed by a narrow V-shaped de­pression; (4) a narrow rib less promi­nent than the preceding ones, followed by a narrow sub-V-shaped ~epress~on; (5) a broad, badly corroded nb, a httle steeper on the left than on the right side, followed by a deep, moderately wide de­pression with a somewhat rounded bot­tom; (6) a narrow rib with equally steep sides, followed by a narrow, deep depres­sion with rounded bottom; (7) a broad, strong, equally steep-sided rib, rendered trifid bv 2 !:-'hallow, narrow crestal de­pression~, and followed by a broad de­}Hession, acentric in cross section, with gentlest slope on the right; (8) a broad, prominent bifid rib with steepest slope on the left, followed by a narrow V-shaped depression; (9) a prominent rib with equally steep sides, followed by the an­terior siphonal band (E). The species is represented only by one lower valve which is incomplete at the small end; the large end appears to be complete except for severe corrosion which has destroyed the impressions of the radial vessels. Dimensions~ as preserved: Maximum length 144. mm.. diameter at small end 62 mm., longest diameter at large end 103 mm., shortest diameter 85 mm., longest diameter of 01wning at large end 56 mm., shortest diameter 40 mm. The flattening of the latter opening on the side opposite the ligamental ridge may be due in part to meC"hanical crushing. The family Hadiolitidae is represc>11ted in the material at hand from the Navarro group, only hy poorly preser\'ed and frag­mentary !"pecimens of Durania from the Nedand\·illc marl at one localitv in Na­\'a;ro County, and by the presen.t species of Sauvaaesia? from the Corsicana marl L near San Antonio. The family appears therefore to he rare in the group. The Salado Creek species bears a gen­ . ? cral resC'mhlance lo ...sauvagesia. acuto. costaJa Adkins:!:ir. from the upper part of the Austin chalk in Travis C-,unty, Texas, but it has fewer and coarser ribs. Sauvagesia? coloradensis Stephenson2311 from the upper part of the Mendez shale in the southern part of the State of Tamaulipas, Mexico, is also a similar species, but it differs markedly in the ap· pearance of its siphonal bands, which are broader and much shallower than those on S? hilli. lfolotype.-U.S.N.M. no. 76575. Named in honor of Dr. Robert T. Hill, eminent pioneer geologist of Texas. Distribution in T'exas.-Navarro group, Corsicana marl: Salado Creek, upstream from Highway 90, Bexar County ( 16671). Genus DURANIA Douville DURANIA? sp. Pl. 37, fig. 13; pl. 38, fig. 7 The material includes imperfect and fragmentary specimens representing 4 or 5 individuals, collected from one soft, calcium carbonate concretion in the Ney· landville marl in a gully in a field, 1.6 miles east-southeast of Black Hills school, ;pl.>..., miles west-northwest of . Corsicana, I Navarro County (16166). U.S.N.M. no. 76576. The most complete specimen is a badly corroded lower valve of which only the thick outer shell layer is preserved. The inner cavity is broadly ovate in cross section and tapers very gradually down­ward; there is no evidence of a liga· mental ridge. The anterior siphonal channel (E) is deep and sub-V-shaped in cross section, and cuts through the shell to within 3 or 4 mm. of the inner surface; the narrow bottom of this channel ( 4 to 10 mm. wide) has been completely broken away; each of the steep sides of the channel is ornamented with 4 or 5 low, longitudinal ribs of irregular width !!35Adkins, W. S., Univ. Texas Bull. 3001, p. 99, pl. 7, figs. 3, 4, 1930. 236Stephcnson, L. W., U. S. Nat. Mus. Proc., vol. 61, art. 1, p. 11, pls. 12·14, 1922. Invertebrate Fossils of the Navarro Group and spacing. The posterior siphonal channel ( S) is not as deep as the an· terior one, and cuts through to within 8 or 9 mm. of the inner surface; it is U-shaped in cross section and is separated from the anterior channel by a prominent round-crested ridge whose sides and crest are ornamented with more or less irregular, low, round-topped longitudinal ribs. The rest of the surface is largely destroyed by corrosion, but wherever pre­served on the different fragments it ex· hibits irregular longitudinal undulations covered with secondary, irregular, round ­crested ribs like those on the sides of the siphonal grooves. The growth layers are thin and closely packed and the cells are small. Internal aurfaces of the shell exposed by breaks parallel to the growth layers exhibit rather widely spaced radial vessels which may fork once or twice in their course from the inner to the outer surface of the shell. Dimensions of the shell shown in plate 37, figure 13: Greatest preserved length 134 mm., greatest preserved diameter 108 mm., diameter of internal cavity at large end 54 mm., at small end about 38 mm. Maximum thickness of shell about 34 mm. Superfamily LUCINACEA Family LUCINIDAE Genus LUCINA Brupiere LUCINA PARVIUNEATA Shumard Pl. 33, figs. 2-6 1861. Lucina parvilineata Shumard, Boston Soc. Nat. Hist. Proc., vol. 8, p. 204. 1928. Lucina( ? ) parvilineata Shumard. Adkins, Univ. Texas Bull. 2838, p. 149. Shell of moderate size, suhcircular to broadly suhovate in oatline, a little longer than high, equivalve, slightly inequi­lateral, depressed convex. Shell wall thin. Beaks small and low, approximate, in­curved, prosogyrate, situated slightly hack of the midlength. Umhonal ridge very faint; posterodorsal slope slightly exca­vated. Hinge not uncovered in the avail­able material, but partly broken margins indicate a rather strong lateral dentition. Internal features of shell not uncovered. The edges of the shell form a nearly reg· ular curve, a little broader, however, on the ventral margin than on the extremities, and the anterodorsal margin is a little excavated just in front of the beak. The surface is nearly smooth, hut exhibits fine growth lines and irregularly spaced, con­centric depressions marking resting stages; on the younger stages of some shells are fine, irregularly spaced, concentric ridges; fine, rather faint, radiating lines, differing in strength on different individuals, are present on both the antero-and postero­dorsal slopes. Dimensions of the neotype: Length 15 mm., height 13 mm., thickness 5 mm. The largest shells in the collections are about 22 mm. long. The shell measured by Shumard was 0.7 4 inch in length, which would be nearly 19 mm. Although Shumard's type specimen is not known to have been preserved, his de­scription of the species is adequate to permit of a satisfactory identification of material from the type locality near Corsicana. His statement that the beak is directed backward indicates that he mistook the posterior for the anterior part of the shell. This species is not apt to he confused with any other described species from the Coastal Plain. Types.-Shumard's type specimen from near Corsicana has apparently been lost. The near Iy perfect shell shown in plate 33, figures 2, 3 (U.S.N.M. no. 76577), has been selected as neotype; 1 typical speci­men figured, U.S.N.M. no. 76578; 1 typical specimen figured, U .S.N .M. no. 76579; 10 unfigured typical specimens, U.S.N.M. no. 20943. Distribution in Texas.-Navarro group, Neylandville marl: 21h miles south of Ben Hur (15543). Navarro group, N acatoch sand: Vicin­ity of Corsicana (763, includes neotype and 1 figured example); north edge of Corsicana (518, 1 example figured); road 5 miles south-southwest of Corsicana (7573); vicinity of Chatfield (762); loose pieces of rock in street at Chatfield ( 7568) ; 2 miles north of Corsicana ( 9553) ; 3 miles northeast of Corsicana (9545); vicinity of Kaufman (761). Range.-The species ranges from the Neylandville marl upward into the Naca· toch sand of the Navarro group. The University of Te:ta.s Publica.tion No. 4101 LUCINA MATTIFORMIS Stephenson, n.sp. Pl. 33, fig. 7 Shell of moderate size, broadly subovate in outline. longer than high, .equivalve, slightly inequilateral, depressed convex. Shell wall of medium thickness. Beaks small and nonprominent, incurved, ap­proximate, slightly prosogyrate, situated nf'ar the midlength of the shell. Antero­dorsal slope slightly excavated; postero­dorsal slope marked by a shallow depres­sion broadening from the beak toward the posterior margin. Hinge not uncovered in the available material. Internal fea­tures of shell not uncovered. The anterior, n:-ntral, and lower posterior margins form a nearlv regular curve a. little broader on the l°';er ;dge. The posterior margin is slightly truncated. The anterodorsal mar­gin is short, horizontal and nearly straight, and the posterodorsal margin is long, in­clined and nearly straight except toward the beak where it is slightly arched. The ~urface exhibits close! y spaced, thin, sharp, concentric ridges which are im­perfectly preserved because of their frail­ness, and between every two of these ridges arc two or more fine, more or less ohscurc incremental lines. The concentric ridges become a little crowded on the dorsal slopes. There are no radiating ribs. Dimen~ions of the holotype, a left rnh-e: Lenf!th about 20 mm., height 18.5 mm., convexity 4 mm. The largest speci­men in the collection is about 22 mm. long. This species is not apt to be confused with any described species from the Upper Cretaceous formations of the Coastal Plain. Its sculpture is wry much finer than that of Lucina glebula. Conrad, from the Snow Hill nwmber of the Black Creek formation, \orth Carolina. Types.--Holotype, U.S.N.M. no. 76580; 2 un fig:u red pa rat ypes, C.S.:\.M. no. 7(>581. Distribution in Texas.-~~n·arro group, 1\acatoch sand: 1~ ·~ miles west of Camp­bell I 12925 I : 1 ~,~ miles northeast of Quinlan I 16162 I ~ field 3, '5 mile west of Kaufman f 1-1103, type lor·.) road 3/5 mile west of Kaufman (1409B ; Yicinity of Kaufman (761) ; 2¥2 miles north of Corsicana (14114) ; road 5 miles south· southwest of Corsicana (7573) ; vicinity of Corsicana (763) ; 4, miles north of Corsicana (l 736(>) . LUCINA LINEARIA Stephenson, n.sp. Pl. 33, figs. 8, 9 Shell small, suhcircular in outline, slightly longer than high, of medium con­vexity, equivalve, slightly inequilateral. Shell wall thin. Beaks small, flattish, slight!y in curved, prosogyrate, situated about midway of the length. Anterior slope flattened a little toward the margin; posterodorsal slope marked by a shal· low depression which broadens toward the posterior margin. Hinge of left valve with two strong cardinal teeth separated by a deep socket; anterior cardinal vertical, short, thick below, thinning above, slightly bifid; posterior cardinal longer, a little oblique, and relatively thin; socket deep, narrow, fiaring a little inwardly. Anterior claspers distant, short, the inner one longer and stronger than the outer one which is very short and weak, the two separated by ·a rather deep and relatively wide socket; posterior claspers more dis· tant and a little longer than the anterior ones, the outer strong one separated from the inner weak one by a deep socket of medium width. Lunule rather wide, pro· found, about 1.5 mm. long; escutcheon narrow, deep, about 2.5 mm. long. Liga· mental groove long, narrow and moder· ately deep. Adductor scars small, situated slightly above the midheight; anterior scar elongated, the lower end diverging in· ward away from the pallial line; posterior scar subovate. Pallial line simple. Inner maqrin of shell faintly and finely crenu· lated. Anterior and ventral margins form· ing a nearly regular curve, the latter a little the broadest; posterior margin sub· truncated nearly vertically. Anterodorsal margin excavated; posterodorsal margin long, inclined, and slightly arched. The surface is ornamented with numerous, Yery thin, sharp, concentric lamellae, well developed all over the surface, but be· coming a little more widely spaced toward the margin; where well preserved these Ini'ertebrate Fossils of the Navarro Group lamellae stand out prominently, hut they are very fragile, and have nearly all been partly broken away; they are most prom­inent on the posterodorsal slope and be­come weaker toward the anterior margin. Dimensions of the holotype, a left \alve: l.ength 5.4 mm., height 4.8 mm., convexity 1.3 mm. This species is not quite as large as Lucina parva Stephenson from the Snow Hill member of the Black Creek formation in North Carolina, and its lamellae are more regular, more prominent and more closely spaced. Compared with Lucina ripleyana Wade, it is larger and its lamellae are more prominent, thinner and more widely spaced. No other de­scribed species from the Cretaceous of the Coastal Plain is apt to be confused with it. Types.-Holotype, U.S.N.M. no. 76582; I figured paratype, U.S.N.M. no. 76583; 2 unfigured paratypes, U.S.N.M. no. 76584. Distribution in T exas.-Navarro group, Corsicana marl: ?5 miles southwest of Quinlan ( 15546) . Navarro group, Kemp clay: Webber­ville ( 7601, type loc.). LUCINA CHATFIELDANA Stephenson, n.sp. Pl. 34, figs. 4, 5 Shell small, subquadrate in outline, equivalve, slightly inequilateral, depressed convex. Umbonal ridge distinct, extend­ing to the lower posterior subangulation; greatest inflation above the midheight at about the midlength; posterior slope mod­erately steep. Beaks centrally located, small, s I i g h t I y prominent, incurved, slightly prosogyrate, approximate. Hinge and internal features not uncovered. An­!erodorsal margin nearly straight, slightly mclined; anterior margin subtruncated, rather sharply rounded below, meeting the dorsal margin above at a broad subohtuse angle; ventral margin broadly rounded; posterior margin subtruncated, with a very broad suhobtuse angle below, and rounding into the nearly straight, slightly inclined posterodorsal margin above. Lunule indistinct) y outlined. The surface is smooth with the exception of fine growlh lines, and slight, irregular growth undula­tions. Dimensions of the holotype, a left vah-e: Length 9.5 mm., height 9 mm., convexity about 2.5 mm. Dimensions of a small nearly perfect shell with both valves at­tached: Length 5. 7 mm., height 5 mm., thickness 2.3 mm. The form of this shell suggests that it belongs in the family Lucinidae, but the hinge has not been seen, and the generic relationships of the shell must be regarded as only tentatively established until the hinge characters have been determined. T)'pes.-Holotype, U.S.N.M. no. 76585; 1 figured paratype, U .S.N .l\tL no. 76586; 6 unfigured paratypes, U .S.N .M. no. 76587. Distribution in Texas.-Navarro group, N acatoch sand: Field south of Chatfield { 7569, type loc.) ~ 3 /5 to 4 :"5 mile northeast of Chatfield (14117); ?vicinity of Kaufman (761). LUCINA SEMINALIS Stephenson, n.sp. Pl. 34, figs. 1, 2 Shell small, subcircular iu outline, of medium com·exity, equivalve, subequi­lateral. Shell wall of medium thickne~s. Beaks moderately prominent, incurved, approximate, prosogyrate, situated cen­trally. Greatest inflation at the midlength, above the midheight, from which point the surface rounds down regularly to the anterior, ventral, and posterior margins. Hinge and other internal features not un­covered. Lunule short, broad, and sharply outlined. Escutcheon wanting. Ligament deeply inset. The regularity of outline is modified by the noticeably excavated anterodorsal margin, and by a slightly fuller curve on the anterior margin than on the posterior. Surface covered with low growth ridges of medium strength numbering about 5 to the millimeter; these are regularly spaced except as mod­ified on the earlier stages by shallow, con­centric depressions that mark resting stages. Dimensions of the imperfeel holotype, the only available specimen: Length 5.5 mm., height 5.6 mm., thickness 3.4 mm. The University of Texas Publication No. 4101 This species is not likely to he confused with any previously described species. Holotype.-V.S.N.l\'1. no. 76588. Distribution in Texas.-Navarro group, Nacatoch sand: 4 milrs north of Cor­sicana (17366). LUCINA OLEODORSUM Stephenson, n.sp. Pl. 34, fig. 3 Shell small, subcircular in outline, de­pressed convex, sulwquilateral. Maximum inflation at the midlength well above the midheight. The regularity of surface cur­vature is modified by a slight radial flat­tening extending from the beak with in­creasing width to the lower anterior mar­gin; the anterodorsal slope is also slightly flattened. Beak 1slightly prominent, in­curved, prosogyrate, situated centrally.· Lunule short, moderately wide, deeply and sharply impressed. Ligament deeply in­set, attached to a narrow, well developed nymph. Dentition feeble, poorly pre­served, but apparently there are two small, short, obscure cardinal teeth in the right valve; anterior lateral of right valve dis­tant, short, nonprominent, separated from the outer margin by a short, shallow socket not well preserved in the holotype; posterior lateral wanting. Other internal features not uncovered. The regularity of marginal outline is modified by a short inclined truncation on the lower antero­dorsal margin: the lower anterior margin becomes a little more sharply rounded as it passes into the ventral margin; the lower posterior margin is also a little more sharpIr rounded where it rounds into the Yentral maqrin: the posterodorsal margin is broad!~-arched. Surface covered with regularly spaced. concentric lines, the interspace~ widenin~ a little toward the outer marp:in: these lines number 3 to 6 to the millimeter: at irregular intervals are stronger ('OJH'C'llt ric depre~sions rnark­in~ resting stap:es. l\ umerous faint, radial Iines may be se~n under a lens. Dimensions of tht· holotype. a right rnh-e: Len~th (>. 7 mm., height (>.6 mm., conYexity 2 mm. Compared with Lucina seminalis this species 1~ a lit~ lP lar~eL proportionately less inflated and lcs~ regular in marginal outli1w. Type.--Holotype, a right valve, the only m·ailable specimen, U.S.N.M. no. 76589. Distribution in Texas.-Navarro group, Nacatoch sand: 1/:.! mile northwest of Oil Ridge School, 4 miles north of Corsicana ( 17366). Unidentified specimens of LUCINA Poorly preserved specimens of Lucina that cannot be specifically identified have been found at the following localities in the Navarro group. In the Nacatoch sand in the northward-facing slope of Sulphur Creek valley, in the northwestern corner of Franklin County (12931, U.S.N.M. no. 76590); on Rock Branch on Walton lease of Houston Oil Co., 1;2 mile north of Corsicana-Chatfield road, 3 miles northeast of Corsicana (9545, U.S.N.M. no. 76591); in the Corsicana marl, in a branch below public road, 21/2 miles north of Tona siding, 5 miles southwest of Quinlan, Hunt County (15546, U.S.N.M. no. 76592). The specimens at the latter place belon~ to a small, smooth, depressed­convex, subcircular species of Lucina; these are internal molds with a trace of shell substance adhering and are more or less compressed and distorted by mechani­cal pressure. Family UNICARDIIDAE Genus UNICARDIUM D'Orbigny UNICARDIUM? sp. Pl. 34, figs. 6, 7 One internal mold of a right valve, with a few fragments of thin shell adher· ing, apparently belonging to the genus Unicardium, was found in the Corsicana marl in a bluff on the left side of Guadalupe River, 1 3/10 miles above McQueeney, Guadalupe County (15524). U.S.N.M. no. 76593. The shell is of moderate size, subtrig· onal in outline, a little longer than high, strongly convex, inequilateral, prob· ably equivalve; greatest ventricosity well above the midheight at about the mid· length; anterodorsal slope steep, exca· vated, subangular above; posterodorsal slope rounding down st~eply to the mar· gin. Beaks prominent, strongly incurved, Invertebrate Fossils of the Navarro Group prosogyrate, situated at about the mid­length. Hinge and internal features not preserved. Anterior margin sharply rounded at about the midheight; ventral margin broadly rounded; posterior mar­gin broadly rounded; posterodorsal mar­gin broadly arched, descending steeply. The adhering shell fragments indicate a surface with small, sharp, closely spaced, concentric ridges; the surf ace of the internal molds shows very faint, radial lines on the anterior part of the shell. This specimen is too imperfect for specific identification, but appears to dif­fer in outline and surf ace features from both Unicardium concentricum (Con­rad) 281 from the Ripley formation at Eufaula, Alabama, and from U nicardium neweme Stephenson from the Snow Hill member of the Black Creek formation at Whiteley Creek Landing, Neuse River, North Carolina. 288 Superfamily LEPTONACEA Family GALEOMMATIDAE Geaua SCINTILLA Deahayea The one available individual, which is tentatively placed in this family, is ques­tionably ref erred to Scintilla solely on the basis of its superficial resemblance in form to the members of that group. The hinge and other internal features are not uncovered, and are therefore not available for determining the family and generic relationships of the specimen. The here­tofore known range of the family is from the Eocene to the Recent. SCINTILLA 7 RAMONI Stephemon, n.ap. Pl. 34, fig. 8 Shell of moderate size, elongated, com­pressed, most inflated posteriorly, equi­valve, inequilateral. Beaks small, low, scarcely projecting, situated about 0.3 the length of the shell from the anterior ex­tremity. Hinge and internal features not uncovered. Anterodorsal margin curving "'Conrad, T. A., Acad. Nat. Sci. Philadelphia Jour., n. ..., YOI. 4, p. 280, pl. 46. fig. 4. 1860. -S..,heneon, L. W., North Carolina Ceol. and Econ. S11ne1, vol. 5, p. 278, pl. 69, fip. 1-3, 1923. down steeply and broadly; anterior mar­gin subtruncated, sharply rounded below; ventral margin long and nearly straight centrally, curving upward at each end; posterior margin sharply rounded much below the midheight; posterodorsal mar· gin passing in a long, broad arch from the extremity upward to the beak. Sur­f ace marked by rather coarse, concentric growth lines and undulations. Dimensions: Length 20 mm., height 12.6 mm., thickness about 5 mm. Holotype.-U.S.N.M. no. 76594. Named for Capt. Domingo Ramon, an early Texas explorer and founder of missions. Distribution in Texas.-Navarro group, Nacatoch sand: Vicinity of Kaufman (761). Superf amily CARDIACEA Family CARDIIDAE Genus CARDIUM Linne The representatives of the genus Car­dium in the Navarro group of Texas, are referrahle to at least four subgenera, Pachycardium C o n r a d, Granocardium Gabb, Ethmocardium White, and Trachy­cardium Morch. Pachycardium is repre­sented by numerous well preserved individuals of one species, and by one internal mold which is specifically in­determinate; five or more species are assignable to Granocardium; one species belongs to Ethmocardium; and Trachy­cardium is represented by one determined species and by several specifically inde­terminate lots of poorly preserved specimens. Sub.enua PACHYCARDIUM Conrad 1869. Pachycardium Conrad, Am. Jour. Conch., vol. 5, p. 96. Type species.-Cardium spillmani Conrad. This subgenus is characterized by its large size, thick shell, elongation in the direction of the height, and near I y smooth surface, with only faintly developed radial sculpture on the umbonal area. Three closely related species of the subgenus, including the new species described be­low, have been differentiated in the American Upper Cretaceous. The Uni-versify of Texas Publication No. 4101 CARDIUM (PACHYCARDIUM) WADEi Stephenson, n.sp. Pl. 38, figs. 1, 2; pl. 39, figs. 4-6 Shell large, thick, subovate in outline, elongated in the direction of the height, moderately convex. Beaks large, promi­nent, strongly incurved, approximate, slightly prosogyrate, situated a little in adrnnre of the midlength. Umbonal ridge broadly rounded. A b;oad, shallow sulcus extends from the um bone to the ventral margin just in front of the umbonal ridge; this sulcus is caused by a pro­nounced thickening of the shell on the anterior slope, and is not reflected on the inner surface of the shell. The anterior slope rounds down broadly, becoming steep toward the dorsal margin; the pos­terior slope is steep and high. The hinge plate is broad and heavy. In the right vake a prominent posterior cardinal tooth is oblique backward, and is separated from a small, short anterior cardinal by a deep triangular socket; back of the posterior cardinal is a relatively shallow, narrow oblique socket. The inner one of the pair of anterior claspers is short and thick and is supported by a buttress-like thickening of the shell back of it; the outer clasper is small and short and is separated from the inner one by a deep, wide socket. The posterior claspers are smaller and shorter than the anterior ones, the inner one being strong and well deYeloped, and the outer one very small and obscure; the socket is moderately wide and deep. The walls of both the sockets are obliquely striated on the sides. In the left Yah-e the anterior cardinal tooth is large, thick and short and is separated from an obscure, narrow, oblique, pos­tPrior cardinal by a deep, triangular socket. The anterior lateral is prominent and short and exhibits concave depressions on the sides. The posterior lateral is smaller and shorter than the anterior one, but is mod­erately promirwnt and distinct~ it has a pronomu·('. is an extreme in plumpness and in abhreYiation in the direction of the height. The dimen~ions of this paratype are: Length 13.5 mm., height 1-1.2 mm., thickness 11 mm. '\'/ e Iler identified this species as Car­d iu m zcenonah \feller. and figured three specimens from near Corsicana. Although the New Jersey species exhibits a super­ficial resemblance in outline and in the number and character of the ribs, the types from the Wenonah sand near Marl­boro do not seem to possess the character­i$tic internal pits, and this, together with the fact that they occupy a stratigraphi­cally lower position, seems to justify sep­arating them from the Texas species. The only other reported occurrence of the subgenus Ethmocardium in the Upper Cretaceous of the Atlantic and Gulf Coastal Plain is in the San Miguel for­mation (upper Taylor age), in Maverick and adjacent counties, Texas, but C. ( Etlzmocardium} zddtei Dall, the type species of the subgenus, is common in the l\fontana group (Upper Cretaceous) of the ·western Interior. Types.-Holotype, U.S.N.M. no. 76600; 1 figured paratype, ll.S.N.:\I. no. 76601; 2 figured paratypes, U.S.N.M. no. 76602a, b; about 2-1 selected unfigured paratypes, V .S.~.l\t no. 76603. Distribution in Texas.-Navarro group, ~acatoch sand: North edge of Corsicana (518); vicinity of Corsicana (763, type loc.) ; road 5 miles south-southwest of Corsicana ( 7573) ; ?2 miles north of Corsicana (9557); 3 miles northeast of Corsicana ( 95-15) ; 4 miles north of Cor­ sicana (17366) ; vicinity of Chatfield {762) ; loose pieces of rock in street at Chatfield ( 7568) ; south of Chatfield (7569); field ~~3 mile west of Kaufman (1-1103); vicinity of Kaufman (761); field 2 miles south bv west of Kaufman (75-17) ; road 2 mile~ south bv west of Kaufman ( 75-16) ; ?l 4i1J miles· northeast of Quinlan 16162). Subgenus GRANOCARDIUM Gabb l\pe ~p('1·it>~.--Carlations haYe therefore not been finally established. Types.--Holot ype. C.S.\".~I. no. 20905; 1 figured paratype. C.S.\".\1. no. 76659; -t. unfigured paratypes, C.S.~.M. no. z''':'tqlhen•on. L. W._ "urth Carolina l,eol. and Econ. :'unn. ml. .5. pt. I. p. :.:: the length of the shell from the anterior extremity. Umbonal ridge wanting on left valve, faintly discernible on right valve. Owing to the twist of the shell the right valve is slightly swollen posteriorly, and the left valve is correspondingly excavated. The hinge of the left valve is set with three cardinal teeth as follows: A nar­row, oblique, slightly curved posterior cardinal tooth, back of a deeply excavated moderately wide socket; a broad bifid middle cardinal, the posterior element of which is narrow and is separated from the broad, forward-sloping element by a nar­row, sharply excavated channel or sub­socket; a long, narrow, oblique, prominent anterior cardinal, bordered on either side by deep, narrow channels. The hinge of the right valve also carries three cardinal teeth as follows: A long, narrow, oblique, sharply bifid posterior cardinal with a deep, narrow socket behind it, and a broad socket in front of it, which is deep pos­teriorly and slopes up anteriorly; the middle cardinal is broad, oblique for­ward, has a high, sharp ridge anterior! y, and slopes toward the rear; in front of the middle cardinal is a deep, narrow socket which is considerably overhung by the short, narrow anterior cardinal. Lat­eral teeth are wanting. The ligamental groove is relatively short, narrow, and deep, and the nymph is narrow and sharp. There is a small lunule set off by a faintly impressed line; back of the beaks The Gnirersity of Te.ra~ Publication No. 4101 is a long. narrow! deeply excavated de­pression. Y-shaped in cross section. which is mechanically necessary to the opening of the two closely compressed vakes. The dorsal margin is hroadlv arched~ the anterior margi1~ beginning ·at the beak is regularly rounded~ becoming just a lit­tle more sharply rounded at the anterior extremity; the ventral margin is broadly rounded: the posterior margin is more sharply rounded than the anterior~ and in most specimens is more or less distinctly suhtruncated. Dimensions of the figured specimen: Lemrth 3 7 = mm.. height 28 mm., con­ ~ L ,-exitY about 3.5 mm. Co.nsidering the common occurrence of this species Lin the Coastal Plain as a whole~ its distribution in Texas, as at present known. is relatiwly sparse~ except in the San 1\liguel formation of the Rio Grande YallevL in l\laYerick and Kinney counties. whe~e it is common. The e~­tremes in outline and form of the shells referred to thls species would seem to _justify splitting it into Yarieties. or eYen species. but the variations noted in speci­mens from one horizon. or eYen from one localitY. are rnch as to induce caution in the subdh-ision of the group. Because of its range and indh-idual variability, the species appears to be of little Yalue in the close discrimination of fauna! zones. Types.-Holotype. _.\cademy of \"atural Sciences of Philadelphia: from the Ripley formation at Eufaula. Alabama. Plesio­type from Texas. r.S.\".\I. no. 76663. Distribution in T exas.-San :\liguel for­ mation: \"orthward-facing bluff of Agua de Fuera Creek Yalley. 5 miles southeast of Spofford. Kinney County ( 8262) ; west­ ward-facin? slope of Elm Creek Yalley, l 1 ~ miles northeast of Paloma. ~laYerick County (8253) : Imperialist Creek~ 2~·2 miles west of Darling siding. Ma,·erick County 18255 I : lmperLialist c~~ek. 3 miles northwest of Paloma sidin2'. :\lawrick Count~-{823-l'i: Del Rio road~ 12~2 miles northwest of Eagle Pass (8226). \"a,·arro group~ :\'eylandYille marl: ~ 2 mile north of Cooper (--1()6.l). \°aYarro group. \"acatoch sand: 11.2 miles west of Campbell ( 12925~ figured) ; }·1-3 miles northeast of Quinlan (16162). :\ayarro group~ Corsicana marl: about 5 miles e~st by north of Greenville I 1292-11 . .:\'a,·arro group, Kemp clay: 41f2 miles northwest of Lockhart (15528, 16151); 31. ~ miles north-northwest of Fentress 061-19). Outside distribution. -Arkansas: Brownstown marl and Nacatoch sand. :Mississippi: Ripley formation and Owl Creek formation. East-central Alabama and Chattahoo­chee region (Alabama-Georgia): Eutaw formation~ Blufftown formation, Cusseta sand, Ripley formation (upper part), and PrO\-idence sand. ':\'orth Carolina: Snow Hill member of Black Creek formation and Peedee forma­tion. Mardand: l\fonmouth formation. :\ew Jersey: \Voodbury clay. Range.-The geographic range of this species is from the Rio Grande to New Jersey, and the geologic range is through the zones of Exogyra ponderosa and E. costat.a, that is, through beds correspond­ing in age to the Taylor marl and the \"ayarro group. CYl>RIMERIA ALTA Conrad Pl. +o~ figs. I. 2; pl. 41, figs. 1-4 1858. Dosirda dcnsata Conrad, Acad. Nat. Sd. Philadelphia lour.. 2d ser.. vol. 3, p. 325, pl. 3-t fi~. 13. (Specific name pre­occupied by Dosinia densata Conrad from New Jersev.) 1875. C.Yprimeria a/ta ·Conrad. Geol. Survey \'orth Carolina Rept.. vol. 1 (by W. C. Kerd. App. A. p. 27. '?1876. CYprimeria torta Gabh. Acad. Nat. Sci. Philad~lphia Proc.. rnl. 28. p. 308. 1916. CYprimeria mafor Gardner. \laryland GeoL Sun·ey. l'pper Cretaceous (2 vols.), P· 689. pl. 4-0. fi~s. 11. 12: pl. 41, figs. 1-4; pl. 42. fig. 1 : pl. 4.3, fig. 1. The Texas shells referred to this species are poorly presen·ed, large, and thick, and e,·idently liYed in a highly favor· able enYironment. They are broadly suh­o\·ate in outline, moderately convex, and exhibit the slight posterior twist to the left. which characterizes the genus. Beaks small, not prominent, approximate, pro­sogyrate. situated about lj3 the length of the she11 from the anterior extremity. Invertebrate Fossils of the Navarro Group Umbonal ridge faintly developed. The dentition on the right valve, as incom­pletely exposed on one right valve, shows the three cardinal teeth essentially as in typical shells from Mississippi {see pl. 41, fig. 2). On a typical Mississippi shell the anterior cardinal tooth of the right valve is thin and sharp; the middle car­dinal is thick, high, steep in front, and slopes off to the socket behind it; and the posterior cardinal is distinctly bifid; behind the latter is a narrow socket which is bordered on the posterior rim by a low, narrow, roughened area. The left valve shows a single, oblique anterior cardinal tooth, thickest toward its forward end, a thick middle cardinal, steep and high posteriorly, gently inclined and slightly bifid on its forward side, and a long, narrow, oblique posterior cardinal which is closely paralleled behind by a lower, narrow, roughened area; the latter stands opposite the similar roughened area in the right valve. The ligamental groove is long, narrow and deep, and the nymph is narrow and sharp-edged. There is a small and not deeply excavated lunule outlined by a faintly depressed line, but there is no well defined escutcheon other than the V-shaped excavation which per­mits the opening of the valves. The an­terior adductor scar is elongated, and there is a small retractor scar back of its upper end; the posterior scar is small and broadly subovate. A row of small irregular pits extends from the retractor scar of each valve back to the apex of the interior under the beak. The pallial line is simple except for a broadly ob­tuse subangulation where the line turns up at the rear toward the posterior adductor. Dorsal margin arched; anterior margin regularly curved, starting at the beak; ventral margin broad Iy curved; the posterior margin is subtruncated below the midheight, obtusely subangular at the extremity, and curves rather sharply above into the posterodorsal margin; there is a slight humping of the margin back of the umbone. The surface is marked by vig­orous incremental lines which become more pronounced on the posterodoral slope. The approximate dimensions of a large, slightly crushed, figured shell from Texas, with the two valves together are: Length 102 mm., height 91 mm., thickness 60­mm. ( ? ) . The dimensions of a typical specimen, a left valve, from Ow1 Creek, Mississippi, are: Length 73 mm., height 65 mm., convexity about 17 mm. The Texas shells, though poorly pre­served, appear to agree well with the typical shells from Owl Creek, Missis­ sippi, both in outline and form, but the former are much larger. If size is to be accepted as a determinative character in separating species, the Texas shells should not be regarded as identical with the Owl Creek shells, but if large size is deter­mined mainly by favorable environmental conditions, as appears to be true with some mollusks, the Texas shells may be ref erred to the Mississippi species. For the same reason Cy primeria rnajor Gardner, from the Monmouth formation of Mary­land, may be placed in the synonymy of C. alta Conrad, for at the same stage of growth the Maryland shells are essen­tiall! identical with typical Ow1 Creek specimens. The beautifully preserved shells from the Coon Creek tongue of the Ripley for­mation in McNairy County, Tennessee, figured by Bruce Wade under the name C. alta Conrad, are more compressed, more elongated, and have a more sharply devel­oped umbonal ridge and a more sharply outlined posterodorsal area than the typi­cal shells from Owl Creek, Mississippi; I have on a following page renamed them Cyprimeria coonensis, and have referred certain Texas specimens to the new species. The type of Cyprimeria excavata (Mor­ton) (= Cytherea excavata Morton) in the Academy of Natural Sciences of Philadelphia is badly broken, but as pre­served it appears to be less inflated and proportionately shorter and higher than C. alta and probably is a distinct species. This conclusion is supported by 3 rather poorly preserved topotypes from Arney­town, New Jersey, the type locality, in the Academy collection. Cyprimeria densata Conrad, from New Jersey, based on a large internal mold, is one of many specific names which, The University of Texas Publication No. 4101 owing to the incomplete preservation of the type specimen, can safely be applied only to that specimen; the mold appears to belong to a much more elongated species than C. alta. C. alta has a fairly close analogue in C. geinitzii Miiller from the greensands (Lowe~ Senonian) of the Aachen district, Germany.253 Types.-The holotype, which should be in the Academy of Natural Sciences of Philadelphia, is not listed among the Cre­taceous types there and is apparently lost. This shell was originally referred by Conrad to Dosinia densata (Conrad), but was later made the type of Cyprimeria alta by the same author. The original figure is good and shells from the type locality on Owl Creek, 21/2 miles north­east of Ripley, Tippah County, Missis­sippi, may be readily identified with it. The figured specimens ( topotypes) shown on plate 41, figures 1-3, are from the type locality in Mississippi (U.S.N.M. nos. 76664, neotype, and 76694). One large specimen (plesiotype) from Texas, showing cracks and some distortion, is fig­ured, U.S.N.M. no. 76665. Distribution in Texas.-Navarro group, Corsicana marl: Near Castroville (7665); near Martindale (15526) ; 3 7/10 miles southwest of Campbell (15547). N aYarro group, Kemp clay: 3~~ miles east of Manor (14158, 155:-H) ; 31/i miles southeast of Manor (16142) ; 2 2/5 miles southeast of Manor (18196, plesiotype) ; near Deatsville (76l) ; ?2~ ~ miles north of Malta ( 1293-1-). Outside distribution.-Mississippi: Owl Creek formation of northern Mississippi and questionably Prairie Bluff chalk of east-central l\1 ississi ppi. Chattahoochee rt>gion, Alabama: Ripley formation (variety?). Maryland: Monmouth formation. Range.-rpper part of the Navarro group and heds of corresponding age m the Atlantic and Gulf Coastal Plain. :.!~.:1Holzapfcl. F.tluard. Die Mollu~kcn 1lt-r :\.achener Krcidc: Palaeontui:raphira, Band :15, p. 17-1, pl. l:?, figs. 1-i, 1889. CYPRIMERIA COONENSIS Stephenson, n.sp. Pl. 40, fig. 4 1926. Cyprimeria a/ta Wad<'. U.S.Gcol. Survey Prof. Papt'r B7, p. 91, pl. 29, figs. 2-4; pl. 30, fi~s. l, 8. The splendidly preserved shells from Coon Creek, McNairy County, Tennessee, described and figured by Bruce Wade under the name Cy primeria alta Conrad, are more elongated and more flattened in the umbonal region than typical specimens of Conrad's species. I therefore rename them. Incomplete specimens from the Naca· toch sand near Kaufman, Kaufman County, Texas, appear to he more like the Coon Creek shells than they are like those from Owl Creek. The right valve shown in plate 40, figure 4, appears to he essentially a duplicate of right valves from the Coon Creek locality, so far as it is preserved. The shell is large, moderately thick, subovate in outline, depressed convex. It is 91 mm. high, but its length cannot be measured; its convexity is about 25 mm. In all of its characters except its greater compression and greater elongation, it ap· pears to be essentially like Cyprimeria alta Conrad. Types.--The cotypes, a complete shell with both valves attached, and a nearly perfect left valve, from Coon Creek, McNairy County, Tennessee, are in the United States National Museum, U.S.N.M. no. 32803. One figured example from Texas, U.S.N.M. no. 76666. Distribution in T exas.--Navarro group, Neylandville marl: Two questionably identified internal molds from 5 miles northwest of Terrell (14.104). Navarro group, Nacatoch sand: Vicin· ity of Kaufman (761, 1 specimen figured) ; field 3 / 5 mile west of Kaufman ( 14103) ; 2;,~ miles north of Corsicana (14114). Outside distribution.-Arkansas: Ques· tionably in the Nacatoch sand in a dug well at Cabot in Lonoke County. Tennessee: Coon Creek tongue of Rip· ley formation. . Range.-The range of the species is be· lieved to be through the Neylandville Invertebrate Fossils of the Navarro Group marl and the Nacatoch sand of the Navarro group, and through beds of cor­responding age in the Gulf Coastal Plain. Genus LEGUMEN Conrad LEGUMEN ELLIPTICUM Conrad Pl. 42, figs. 13-19 1858. Legumen ellipticus Conrad, Acad. Nat. Sci. Philadelphia Jour., 2d ser., vol. 3, p. 325, pl. 34, fig. 19. 1858. Legumen appressus Conrad, Acad. Nat. Sci. Philadelphia Jour., 2d ser., vol. 3, p. 325. 1877. Legumen planulatus (Conrad). Gabb, Acad. Nat. Sci. Philadelphia Proc., vol. 28, p. 304. 1885. Legumen ellipticum Conrad. Whitfield, U. S.Geol. Survey Mon., vol. 9, p. 184, pl. 25, fig. 5. (Geol. Survey New Jersey, Paleontology, vol. 1, p. 184, pl. 25, fig. 5, 1886.) ?1885. Legumen planulatum (Conrad). Whit­field, U.S. Geol. Survey Mon., vol. 9, p. 184 pl. 25, figs. 3, 4 ( ? ) . (Geol. Survey New Jersey, Paleontology, vol. 1, p. 184, pl. 25, figs. 3, 4 ( ? ) , 1886.) 1905. Legumen ellipticum (Conrad). Johnson, Acad. Nat. Sci. Philadelphia Proc., vol. 57, p. 17. ?1907. Legumen planulatum (Conrad). Weller, Geol. Survey New Jersey, Paleontology, vol. 4, p. 612, pl. 69, questionably figs. 3, 4, probably not figs. 5--7. 1916. Legumen planulatum (Conrad). Gardner, Maryland Geol. Survey, Upper Creta­ceous (2 vols.), p. 684, pl. 40, figs. 5-7. 1926. Legumen planulatum (Conrad). Wade, U. S.Geol. Survey Prof. Paper 137, p. 90, pl. 29, fig. 1. Shell thin, greatly elongated, subel­liptical, inequilateral, equivalve, com­pressed. Beaks small, not prominent, in­curved, approximate, situated about one­fourth the length of the shell from the anterior extremity. There is no umbonal ridge. The shell is most inflated at about the upper third of its height, and parallel to its long axis, and slopes gently toward the anterior, ventral, and posterior mar­gins, and more steeply toward the dorsal margin. The dental formula is L.101010 R.010101. In the left valve the two posterior cardinal teeth are long, oblique, thin, and separated by a deep narrow socket; the anterior cardinal is short, nearly vertical beneath the beak, moderate! y thick and slight! y bifid on its inner edge, and thins wedge­like upward; a deep, wide triangular socket lies back of the anterior cardinal and a deep, narrower socket in front of it. There are no lateral teeth. In the right valve the posterior cardinal is long, thin, oblique and deeply bifid; it is bor­dered behind by a long, narrow, deep socket, and in front by a wide, triangular, deep socket; the two anterior cardinals are short, thin, nearly vertical beneath the beak, and separated by a narrow, deep socket. The ligamental groove is long and narrow and is bordered below by a thin nymph. There is neither lunule nor escutcheon. The anterior adductor scar is of moderate size, subovate and situated above the midheight; the posterior ad­ductor is large, subovate, elongate parallel to the dorsal margin, and lies high in the shell; the pallial sinus, though distinctly developed, is not profound; it lies close below the posterior adductor, pointing for­ward, but falls considerably short of reaching the anterior end of the adductor. The inner margin is smooth. The margins of the shell form a greatly elongated subellipse, with a slight truncation on the lower posterior margin; on .:.iccount of the great elongation both the dorsal and ventral margins are nearly straight. The surface is marked only by incremental lines, which vary somewhat in their coarse­ness on different parts of the shell; they show a tendency to become more sharpI y defined toward the ventral margm, especially its forward portion; the shell is, as a rule, smoother in the umbonal region than elsewhere. Dimensions of the right valve shown in plate 42, figure 18: Length 44.5 mm., height 19 mm., convexity 3 mm. The species exhibits considerable variation in the proportion of length to height even among specimens from the same locality. Legumen appresszun Conrad, which was described, but not figured, immediately following the original description of L. ellipticum Conrad, was probably a younger individual of the latter species. Compared with Legurnen concentricum Stephenson, from the Snow Hill member of the Black Creek formation in North Carolina, the concentric sculpture of this species is much finer, and the beak is a little nearer the anterior extremity, and The Uni-versity of Texas Publication No. 4101 there can be no reasonable doubt that it is speci fieally distinct. Most authors have placed this species in the synonymy of Legumen planulatwn (Conrad), a species based on an internal mold from '~Monmouth County, New Jer­sey." That specimen may have come from any one of 8 or 9 Upper Cretaceous forma­tions between the Raritan formation at the base and the Red Bank sand at the top. \Vithin this series there is at least one other species, L. concentricwn Stephenson, the internal mold of \vhich is practically in­distinguishable from that of L. ellipticum Conrad; this fact makes it impossible to demonstrate that either of these species should be regarded as synonymous with L. planulatwn (Conrad), a name which can be safely applied only to the type specimen. Both L. ellipticUTn and L. con­centricwn are based on nearly perfect type material, and proof that either one is identical with L. planulatUTn has not been given by any of the authors who have accepted such identity. Types.--The holotype is in the Academy of Natural Sciences of Philadelphia. The specimens figured on plate 42, figures J3-15, are topotypes from Owl Creek, Tippah County, Mississippi ( U .S.N .M. nos. 76667, 76668). Plesiotypes from Texas, U.S.N.M. nos. 76669, 76670. Distribution in Texas.--Navarro group, Neylandville marl: 1h mile north of Cooper (14062). Navarro group, Nacatoch sand: Road 3 ·5 mile west of Kaufman (7545, 12923, 14098); field 3/ 5 mile west of Kaufman ( 14103, 2 specimens figured) ; vicinity of Kaufman ( 761) ; road 2 miles southwest of Kaufman ( 7546) ; vicinity of Chatfield ( 762, 1 specimen figured) ; loose pieces of rock in street at Chatfield (7568) ; field south of Chatfield ( 7569) ; 34 mile east of Chatfield ( 7571) ; 3 / 5 to ·J;i mile northeast of Chatfield (14117) ; 3 miles northeast of Corsicana (9545) ; Watkins' place 4 miles north of Corsicana (9558) ; 4 miles north of Corsicana (17366) ; north of Rock Branch 3 miles northeast of Cor­sicana (9560) ; vicinity of Corsicana I 763) ; north edge of Corsicana (518) ; 2~~ miles north of Corsicana (14114) ; road 5 miles south-southwest of Corsicana ( 7573) ; 5 miles northeast of McClanahan ( j 7371). Navarro frroup, Cor~icana marl: 1 3/10 miles north of McQueeney ( 7637) ; 1% miles N. 20° W. of Tona siding (15545); 5 miles southwest of Quinlan (15546); 3 7,:10 miles southwest of Campbell (15547) ; about 5 miles east by north of Greenville (12924) ; 114 miles south by east of Oak Grove (13568, 16160). Outside distribution.-Mississippi: Rip­ley formation and Owl Creek formation. Tennessee: Coon Creek tongue of Rip· ley formation. Chattahoochee region (A l a b am a. Georgia) : Ripley formation and Provi· dence sand (marine facies). Maryland: Monmouth formation. Range.-Navarro group and beds of Navarro age in the Atlantic and Gulf Coastal Plain. Representatives of the genus Legumen, generally poorly pre· served, which are closely related to this species, occur in beds of Taylor age, notably in the San Miguel formation. It may therefore be found that this species ranges downward into these older beds. Genus TENEA Conrad 1870. Tenea Conrad, Am. Jour. Conch., vol. 6. p. 72. Type species.-Tenea parilis Conrad. Conrad:!:i·1 in February, 1860, described the species Mysia parilis, which he re· corded as having been sent to him by Dr. "\X1• Spillman, from Tippah County, Mississippi. Presumably the type came from Owl Creek (Owl Creek formation), 2% miles northeast of Ripley, where Doc· tor Spillman obtained most of the fossils which he submitted to Doctor Conrad. In 1870, Conrad described the new genus Tenea and cited T. parilis Conrad l = Mysia parilis Conrad) as the type. Mysia parilis Conrad was from Tippah County, Mississippi, but the shell on which he observed the hinge features de· scribed as charaderistic of the genus came from the Woodbury day at Haddonfield, New 1ersey. The description of the genus ~~>4Conrad, T. A.• Acad. Nat. Sci. Ph:Iadelphia Jour., 2d ser., vol. 4, p. 27B, pl. 46, fig. 17, 1860. Invertebrate Fossils of the Navarro Group is therefore based on material identified as belonging to the species T enea parilis, and not on material from the type locality of that species. Presumably the Haddon­field material was correctI y referred to Tenea parilis. Although Doctor Dall, in the second edition of Eastman's translation of Zittel's Textbook of Paleontology ( p. 487, 1913), listed Tenea as a genus under Diplodontidae, he had at an earlier date, 1900, correctly included it under the Veneridae255 ( sensu lato) . The hinge as seen in well preserved shells from the Ripley and Ow1 Creek formations of Mississippi is a modification of a hinge of the Cyclorisma type.256 In Tenea the posterior, oblique, bifid tooth of the right valve has become so widely and deeply bifid that it has the appearance of two separated teeth; the upper end of the anterior element of this bifid tooth has become united with the upper end of the anterior cardinal tooth, and the in­termediate cardinal has dropped down to an abnormally low, nearly horizontal po­sition, and become separated from the anterior cardinal by a deep, nearly hor­izontal notch. In the left valve the two anterior cardinal teeth have become united at their tops to form an inverted V-shaped double tooth, and this tooth has dropped and become separated from the margin of the shell above by a narrow, deep slit; the wide, oblique socket back of the V-shaped tooth accommodates both of the widely separated elements of the bifid tooth of the right valve; the floor of this socket is slight! y raised centrally. Lateral teeth are wanting. The pallial line is serrated in front of the pallial sinus; the pallial sinus is narrow, moderately high and sharpIy angular above. The inner margin of the shell is smooth. TENEA PARILIS Conrad Pl. 42, figs. 9-12 1860. Mysia parilis Conrad, Acad. Nat. Sci. Philadelphia Jour., 2d ser., vol. 4, p. 278, pl. 46, fig. 16. (Called Diplodonta parilis in plate explanation, p. 298.) 2156Dall, W. H., Wagner Free ln9t. Sci. Trans., vol. 3, pt. 5, p. 1181, 1900. llMIStephenson, L. W., North Carolina Geol. and Econ. Survey, vol. 3, pt. 1, pp. 316·318, pl. 80, figs. 1-5, 1923. 1870. Tenea parilis Conrad, Am. lour. Conch., vol. 6, p. 73, pl. 3, fig. 12. ?1875. Tenea parilis Conrad, Geol. Survey North Carolina Rept., vol. 1 (by W. C. Kerr), App. A, p. 8, pl. 2, fig. 25. 1884. M_vsia (Ten.ea) parilis (Conrad). Tryon, Systematic and structural conchology, vol. 3, p. 216, pl. 119, fig. 72. 1885. Tenea pinguis Conrad. Whitfield, U.S. Geol. Survey Mon., vol. 9, p. 163, pl. 22, figs. 1-3. (Geol. Survey New Jersey, Paleontology, vol. 1, p. 163, pl. 22, figs. 1-3, 1886.) ? 1885. Dosinia gabbi Whitfield, U.S.Geol. Survey Mon., vol. 9, p. 161, pl. 22, figs. 4, 5. ( Geol. Survey New Jersey, Paleontology, vol. 1, p. 161, pl. 22, figs. 4, 5, 1886.) 1905. Tenea parilis Conrad. Johnson, Acad. Nat. Sci. Philadelphia Proc., vol. 57, p. 15. 1907. Tenea parilis Conrad. Weller, New Jersey Geol. Survey, Paleontology, vol. 4, p. 572, pl. 63, figs. 1-6. 1916. Tenea parilis Conrad. Gardner, Maryland Geol. Survey, Upper Cretaceous (2 vols.), p. 661. 1926. Tenea parilis Conrad. Wade, U.S.Geol. Survey Prof. Paper 137, p. 83, pl. 26, fig. 1. Shell of medium size, subcircular to broadly subovate in outline, equivalve, inequilateral, moderate!y ventricose, most inflated centrally above the midheight; the species exhibits considerable individual variation in outline, ranging from a little longer than high to a little higher than long. Beaks prominent, incurved, closely approximate, prosogyrate, situated about midway of the length. Margins regularly rounded, forming almost a circle. An­terior adductor scar small, elongated, situated high up toward the dorsal mar­gin; posterior adductor scar obscure, situated low in the shell. Pallial line ser­rated in front of the pallial sinus which is narrow, low down in the shell, slightly inclined forward, and rises to a sharply angular terminus centrally at about the midheight. The inner margin is simple. Surface marked only by incremental lines becoming a little coarser ventrally and showing some resting stages. Dimensions of the left valve shown in plate 42, figure 9: Length 23 mm., height 24 mm., convexity 8 mm. Dimensions of a smaller nearly perfect shell: Length 15.5 mm., height 15 mm., thickness 8.8 mm. The types of Lucina pinguis Conrad and Mysia gibbosa Gabb, both of which have been regarded by authors as specifically The University of Texas Publication No. 4101 identical with T. parilis, are internal molds representing a shell more inflated and more circular in outline, and not only belong to a different species, but probably to a different genus. Types.--Conrad's types of Mysia parilis from Tippah County, Mississippi, and T enea parilis, from Haddonfield, New Jersey, are preserved in the Academy of Natural Sciences of Philadelphia. Hinges from the Ow I Creek formation, Ow I Creek (U.S.N.M. no. 76671) and from the Ripley formation near Dumas (U.S.N.M. no. 20752) , Mississippi, are figured. Two plesiotypes from Texas, U .S.N .M. no. 76672. Distribution in T exas.-Navarro group, Neylandville marl; 21/2 miles south of Ben Hur ( 15543) ; 3% miles west-north­west of Corsicana (16166). Navarro group, Nacatoch sand: Vicin­ity of Corsicana ( 763) ; north edge of Corsicana (518, 2 specimens figured); road 5 miles south-southwest of Corsicana ( 7573) ; 2V2 miles north of Corsicana (14114); 4 miles north of Corsicana (17366); 21h miles west by south of Corsicana ( 17368) ; vicinity of Chatfield (762) ; 6 miles southeast of Cooper (12929). Navarro group, Corsicana marl: About 5 miles east by north of Greenville (12924). Navarro group, Kemp clay: ?From a well near old Garfield (1641). Outside distribution.-Arkansas: Naca­toch sand. Tennessee: Ripley formation (Coon Creek tongue) . Mississippi: Ripley formation and Owl Creek formation. East-central Alabama and Chattahoochee region (Alabama-Georgia) : Questionably in Blufftown formation, in upper part of Ripley formation, and in Providence sand. Maryland: Matawan formation and Monmouth formation. New Jersey: Woodbury clay, Navesink marl, and Red Bank sand. Range.-Ranges through the zones of Exogyra ponderosa and Exogyra costata in the Atlantic and Gulf Coastal Plain. Genus CYCLORISMA Dall In its O'eneral outline and form, and b . h in its smooth surface t e one species Cyclorisrna? pumila, referred to this o·enus is much like Conrad's genus Tenea, ~!though much smaller. The hinge is rather incompletely exposed on several specimens and these show that the species does not belong to Tenea. The hinge is like that of Cyclorisma Dall in that the right valve possesses one strong, bifid, posterior cardinal tooth, very oblique toward the rear, a deep wide socket in front of this tooth, and two thin anterior cardinal teeth oblique forward, and sep· arated by a narrow, deep socket; and the left valve possesses two subequal cardinal teeth under the beak, the anterior one oblique forward, the other nearly vertical, separated by a deep socket, and one dis· tant, weak, oblique posterior cardinal, separated from the middle cardinal by a wide, oblique socket. The species is a pigmy alongside the previously described species of Cyclorisma and this fact, together with its relatively thick shell, and the possession of a faintly defined lunule which is lacking on Cycloris1na, throws doubt on its really belonging to that genus. However, the generic relationships of the species can not be satisfactorily determined until a more complete exposure of the hinge is obtained. CYCLORISMA? PUMILA Stephenson, n.sp. Pl. 39, figs. 7, 8 Shell small, subcircular to broadly subovate in outline, equivalve, slightly in· equilateral, moderate! y ventricose, most inflated above the midheight. Shell wall relatively thick. Beaks prominent, in· curved, closely approximate, prosogyrate, situated about midway of the length. Margins regularly curved forming almost a circle. Lunule faint!y but certainly de· fined on some specimens. Internal fea· tures not clearly exposed on any specimen, but a faint impression of the pallial sinus on one internal mold appears to indicate that it is rather small and narrow and of only moderate depth. Inner margin smooth. Surface smooth except for fine Invertebrate Fossils of the Navarro Group incremental lines and irregularly spaced concentric depressions which mark rest­ ing stages in growth. The hinge described above is essentially like that of Cyclorisma Dall. Dimensions of the holotype: Length 7 .6 IDDl., height 7.6 mm., thickness 5.2 mm. Dimensions of a smaller, nearly perfect shell: Length 6.4 mm., height 6.3 mm., thickness 4.1 mm. Types.-Holotype, U.S.N.M. no. 76673; 2 unfigured paratypes, U.S.N.M. no. 76674; 2 unfigured paratypes, U .S.N .M. no. 76675; I unfigured paratype, U .S.N .M. no. 76676; about 60 unfigured paratypes, U.S.N.M. no. 76677. Distribution in Texas.-Navarro group, Nacatoch sand: Vicinity of Chatfield (762, holotype and 60 unfigured para­types) ; loose pieces of rock in street at Chatfield (7568) ; Watkins' place 4 miles north of Corsicana ( 9558) ; 2 miles north of Corsicana (9554, 9555); north edge of Corsicana (518); vicinity of Corsicana (763) ; road 5 miles south-southwest of Corsicana (7573, loc. of 2 unfigured para­types) ; road 3 /5 mile west of Kaufman ( 7545, loc. of I unfigured paratype; 14098); field 3/5 mile west of Kaufman (14103, loc. of 2 unfigured paratypes) ; vicinity of Kaufman (761). Superfamily TELLINACEA Family TELLINIDAE Genus TELLINA Linne TELLINA MUNDA Stephenson, n.sp. PI. 42, figs. 1-5 Shell of medium size, thin, subelliptical in outline, depressed convex, inequilateral, inequivalve, bent to the right posteriorly, making the left valve appear more ventri­cose than the right. Beaks small, non­prominent, nearly direct, slightly in curved, approximate, situated slightly back of the midlength. Hinge not uncovered. Liga­mental groove short, deep, and narrow; ligament partly preserved on one specimen. Adductor scars subequal; anterior scar aubovate, posterior scar subtrigonal, elongated. Pallial sinus deep, nearly horizontal, extending beyond the mid­length. The antero-and posterodorsal margins diverge from the beak at an angle of about 140 degrees, both margins being slightly arched; anterior margin sharply rounded; ventral margin very broadly rounded; posterior margin subangular be­low, subtruncated above, sloping forward and rounding into the posterodorsal mar­gin. The internal mold shows 3 faint shallow depressions radiating from the beak in the umbonal area, 1 extending obliquely backward and downward, and the other 2 extending less obliquely for­ward and downward. The surface is polished, and exhibits delicate radiating lines, and stronger thread-like concentric depressions numbering 5 to 8 to the milli­meter. An internal mold at one locality in the Kemp clay appears to differ in no essential respect from this species, except that it is a little larger than any yet found in the N acatoch sand. Dimensions of holotype: Length 22 mm., height 13 mm., thickness 4.3 mm. The members of the genus Tellina are difficult to classify, because of their sim­plicity and the slight differences in form and outline that have to be depended upon in separating species. This species is characterized by its flatness and its nar­row, truncated posterior margin. It is similar to T. gabbi Gardner, but has finer concentric sculpture and appears to be relatively more elongated. Types.-Holotype, U.S.N.M. no. 76678; I figured paratype, U.S.N.M. no. 76679; I figured paratype, U.S.N.M. no. 76680; 4 unfigured paratypes, U.S.N.M. no. 76681. Distribution in T exas.-Navarro group, N acatoch sand: I 4/5 miles northeast of Quinlan (16162); road 3/5 mile west of Kaufman ( 14098) ; road, 2 miles south­west of Kaufman ( 7546) ; vicinity of Chat­field ( 762, loc. of holotype and 5 para­types, 1 figured) ; loose pieces of rock in street at Chatfield (7568); ?3/5 to 4/5 mile northeast of Chatfield ( 14117) ; 3 miles northeast of Corsicana ( 9545) ; Watkins' place 4 miles north of Corsicana (9558) ; 4 miles north of Corsicana (17366); road 5 miles south-southwest of Corsicana (7573, loc. of 1 figured para­type); north edge of Corsicana (518). Navarro group, Kemp clay: ?4% miles northwest of Lockhart ( 16151). Range.-Ranges questionably from the Nacatoch sand upward into the Kemp clay of the Navarro group. The Unii-ersity of Te.-ras Publication No. 4101 TELLINA? MARCOSENSIS Stephenson, n.sp. Pl. 41. figs. 5, 6 Shell small, subelliptical in outline, de­pressed com·ex. Beaks not preserYed but obYioush-low and flattish. situated a little back of. the midlength. . Cmbonal ridge faintly deYeloped. The dorsal margins diYerge from the beak at a wide obtuse angle; anterior margin sharply rounded; Yentral margin broadly rounded; posterior margin subtruncated below the midheight~ rounding broadly into the posterodorsal margin abo,·e. The surface is marked by two distinct kinds of sculpture. On the anterior and central parts of the shell rather strongly impressed line-like depres­sions are regularly spaced about half a millimeter apart and are separated by low, broad ridges which number about 10 to half a centimeter; a little back of the mid­length 3 or -1 fine lines appear in each of the interspaces between the stronger lines~ and within 2 mm. back of the first appear­ance of the fine lines, the coarser lines disappear and giYe place entirely to the finer lines which mark the remainder of the surface to the terminus of the shell and number 8 or 9 to the millimeter. Dimensions: Length 12.8 mm., height 7.5 mm., conwxity about 1 mm. The species is represented by the mold of one right Yah-e, which dearly shows the outline, form and surface sculpture, but which does not rewal the hinge or in­ternal characters. The species may be reasonabh-referred to the Tellinidae but can only. be pro,·isionally referrt>d to T ellina. T.? patu la is a Y;.."'ry elosely re­lated species. Holotype.-CS.:\.i\I. no. 76682. Distribution in Te.rns.-:\a,·a1-ro ~roup, Corsicana marl: 1 ~ mile below \lartindale (7621). Range.-Known only from the type locality. Howen"'r. T.? patula in the ::\ey­land,·ille marl and in the :\acatoch sand indicates a range of this closeh-related group from th~ :\eyland,·ille inarl up­ward into the Corsicana marl of the :\a­Yarro group. TELLINA? PATULA Stephenson, n.sp. Pl. 41. figs. 7. 8 In form and sculpture this speciPs ap­pears to be e5sentially like that of T.? marcosensis excPpt that it is more coarsely sculptured. Although somewhat variable the impressed concPntric lines average more than half a millimeter apart so that the intern"'nirw low ridges number about 3 in a widtht:-of 2 m~n. This relative coarseness is also manife~ted in the finer lining which charactPrizcs the posterior part of the shell. On some specimens the coarseness of the ribbing seems to de­crease a little toward the ven~ral margin. Approximate dimensions of the holotype, an imperfect internal mold with frag­mentary shell material adhering and with concentric lines clearly impressed: Length 11 mm., height 7 mm., convexity I mm. Types.-Holotype, U.S.N.M. no. 76683; 1 paratype, U.S.N.M. no. 76684. Distribution in Texas.-Navarro group, Neylandville marl: 2~,~ miles north of Corbet (16170, holotype; 17365); 3 miles northeast of Drane (16164, paratype). Navarro group, Nacatoch sand: 3/5 to 4 ·5 mile northeast of Chatfield (14117); ?3 miles northeast of Corsicana (9545); 4 miles north of Corsicana (17366). Range.-Neylandville inarl and Naca· toch sand of Navarro group. Unidentified specimens of TELLINA Imperfectly preserved specimens of Tellina, which cannot be satisfactorily identified, have been collected from the l\acatoch sand as follows: Near Kaufman, a small elongated species, relatiYely more ventricose than Tellina munda., is represented by the in­ternal mold of a right valve (761, U.S.N.M. no. 21030), by an internal mold of an indiYidual with both valves attached (U098. U.S.N.M. no. 76685:), and by the internal mold of a right valve with some shell material attached showing rather strong concentric sculpture (7545, U.S. l\'.l\t no. 76686) . From the latter locality (75-15, U.S.N.M. no. 76687) is an internal mold of a left valve with some shell ad· hering on the umbone, which is still more Yentricose and exhibits a still stronger concentric sculpture. In a field north of the Dallas road, 3/5 mile wt>st of Kaufman (14103) a small left vah-e is represented by the interior of the shell embedded in the sandstone matrix, by the internal mold of the same specimen, and by another internal mold of about the same size; this form is elongated Invertebrate Fossils of the Navarro Group ~~rsto be less ventricose than the p . · g, but more ventricose than T. muntla. U.S.N.M. no. 76688. In the public road at Simpson's Hill, 2 miles southwest of Kaufman (7546), was found the internal mold of a large left valve, apparently of a Tellina, which dif­fers from T. munda in that it is more elongated, more ventricose, has a pro­nounced umbonal ridge, and is much more pointed posteriorly. U.S.N.M. no. 76689. Near Kaufman ( 761) was also found a rather large, imperfect internal mold of a Tellina, with shell substance partly ad­hering, which is rather ventricose centrally and has narrow, sharply rounded anterior and posterior extremities. The specimen does not appear to match any described species but is too imperfect to serve as a type. U.S.N.M. no. 76690. Imperfect specimens of T ellina have been found at two localities in the Corsi­cana marl as follows: In a small branch below the public road, 21h miles north of Tona siding, 5 miles southwest of Quinlan (15546, U.S.N.M. no. 76691), an e1ongated internal and nartial external mold has the characteristic& form of Tellina and measures: Length 27.5 mm., height 14 mm., thickness 5 mm. ; a larger internal mold from a road ditch in the westward­facing slope of Lynne Creek valley, 3 7/10 miles southwest of Campbell, Hunt County (15547, U.S.N.M. no. 76692), is relatively hiPer, rather thick, has the form of TiUina, and measures: Length 36 mm., height 24 mm., thickness 11.3 mm. A small Tellina-like pelecypod repre­eented by impressions, was obtained in the Kemp clay on Elm Creek at the crossing of the Corsicana-Angus road, 3 miles south of Corsicana, Navarro County (9550) ; it ii characterized by rather coarse, concen · trie markings. U.S.N.M. no. 76693. Genua LINEARIA Conrad Conrad's257 original description of the genus Linearia is brief, somewhat inac­curate, and in part contradictory. He states in the first paragraph that there are two cardinal teeth in the left valve, the anterior one elongated, very oblique, and •Coarad, T. A., Acad. Nat. Sci. Philadelphia Joor., 2d -·· YOI. 4, p. 279, 1860. the posterior one under the beak, small and bifid. In the next paragraph he states, apparently inadvertently, that he has only a right valve. The description seems to pertain to a left valve. I have not seen a left valve from the Ripley formation at Eufaula, Alabama, the type locality, but a perfectly preserved left valve, apparently of the type species, L. metastriata Conrad, from the Provi­dence sand (marine facies) on Chatta­hoochee River at the mouth of Pataula Creek, about 12 miles below Eufaula, shows the hinge features clearly. There is a long, strong, anterior cardinal extend­ing forward and a little downward, be­coming thicker anterior 1y; above this tooth is a long, narrow, deep socket; below the beak is a degenerate, small, short, vertical cardinal tooth, the crest of which is very faintly divided into two nodes which are hardly distinct enough to justify describ­ing the tooth as bifid; the small tooth is separated from the large one by a deep socket opening widely toward the interior. On one left valve from Owl Creek, Missis­sippi, the long anterior cardinal is slightly bifid at its distal end. There are small, distant anterior and posterior laterals on the margin of the shell. A right valve from the same locality possesses two sim­ple, elongated cardinal teeth pointing forward and a little downward, separated· by a deep, narrow socket; under the beak is a very small node-like rudimentary posterior cardinal tooth; pairs of distant, short anterior and posterior claspers ac­commodate the laterals of the left valve. These features have been observed also on right and left valves of L. metastriata from the Owl Creek formation of Missis­sippi. The rudimentary posterior cardinal of the right valve is especially well shown as a very small, narrow tooth extending backward and downward, on a well pre­served shell from the lower part of the Ripley formation on Coon Creek, McNairy County, Tennessee. 258 There is a tendency on the larger species of the genus for the small, vestigial cardinal teeth to disappear, and the same may be said of the lateral teeth and claspers. Jl58Wade, Bruce, U. S. Geol. Survey Prof. Paper 137, p. 93, pl. 31, figs. 1, 2, 1926. LINEARIA WIESERAE Stephenson, n.sp. Pl. 40, fig. 8 Shell broadly subovatc in outline, in­equilateral, sul~equivalve, depressed con­vex. Beaks poorly preserved, but appar­ently flattish, nonprominent, slightly prosogyrate, situated about midway of the length. The hinge is not uncovered. The shell was temporarily peeled off of the cast of the holotype and revealed subequal, broadly subovatc adductor scars situated high on the inner surface; also a relatively narrow, profound pallial sinus, rather sharply rounded anteriorly, rising some­what and reaching beyond the midlength. The antero-and posterodorsal margins diverge from the beaks at an angle of about 130 degrees; anterior margin regularly and rather broadly rounded; ventral mar­gin very broadly and evenly rounded; posterior margin rather sharply rounded below, subtruncated above, rounding into the nearly straight, sloping posterodorsal margin. The surface is ornamented with 33 or 3..i narrow, low, hut sharply defined ribs which are differently spaced on dif­ferent parts of the shell; one rib closely borders the posterodorsal margin and is bordered in front by a smooth, flat inter­space fully 2 mm. ~ride; in front of this interspace 6 ribs are crowded in a space only 4 mm. wide; from this band forward a little past the midlength the ribs are 1.5 to 2 mm. apart and arc separated by flat, smooth inters paces; from the prC'ceding forward to the edge of the anterior slope the ribs are again widely spaced, number­ing only .1, or 5. Each rib supports a row of small nodes, spaced at irregular inter­vals of 0.5 to 2 mm. Fine' concentric lines of growth cm·er the shell and toward the front these become a little stronger and tend to produce a finf'ly cancellated sur­face. Dimensions of the holotype. a right valve: Length :1 l mm., height 27.8 mm., c·on\'exity about 5.7 mm. The ornamental ion of this species re­semhlt·s that of Linearia. me/as/riata Con­rad, the typf' ~PC'<'ies of the gPnus~ in that radiatinµ: costae cover the entire surface of the shell. hut this Texas shell is much largPr and more coarsely seul ptured, and lacks the strong development of concentric ribs exhibited by Conrad's species. Holotrpe.-U.S.N.M. no. 76~95. Named in honor of Miss Frances Wieser, Illus· trator, United and most wideh· spaced on the rihs of the anterior slope.: on the main part of the :'hell these nodes are small and closely spaced: the ribs are strongPSt and mo:'t widely spaced on the anterior slope. les~ strong and somewhat Z:·PCnnra •L T. .\. . G.·ol. ~un·1·y '.\,lrth Carolina Rept., ,-ol. I lb~· W. C. Kn~I. :\pp. . .\. p. 9. pl. I , fig5. 20, 23, ~t. 187.'i. closer together on the weakly developed umbonal ridge, and fine and closely set lWcr the remainder of the surface. The shell is do~eh related to l. zcieserae, from "hieh it app~ars to differ in having finer, sharper. and more closely spaced ribs. r .s.~.~I. no. 209-19. Two small internal molds which may represent two species of smooth Linearia were found in the :\"acatoch sand on Rock Branch on the '\\'alton lease of the Houston Oil Company, ~,~ mile north of the Cor· sicana-Chatfield road, 3 miles northeast of Corsicana, NaYarro County (9545). CS.:\'.~I. no. 76702. A fragment of an internal mold of a linea.ria~ showing an impression of the sculpture, was found in the Corsicana marl in a branch on the 'Wm. H. Moore Survey. 6 miles east by north of Green­Yille. Hunt County {12924). The shell is small, relatively plump, and is covered with a fine, cancellated sculpture produced by uniformly spaced, radiating and con· centric ribs. The sculpture resembles that of L. metastriaJa Conrad, but the shell appears to be too ventricose for that species. r.s.~.M. no. 76703. SeYeral imperfectly presen'ed specimens of a small species of linearia, with a trace of the shell substance adhering, were ob­ tained from the Corsicana marl, from the left bank of San Marcos River, 112 mile below .\lartindale, C a I d w e l l County 115527). The sculpture consists of fine, sharp~ regularly spaced, concentric lirae, numbering 5 or 6 to the millimeter, nar· rower than the interspaces, over the main surface~ 5 or 6 radiating costae, much nar· rower than the intersp;ces, on the antero­ dorsal slope, and a dozen or more radiating costae. narrower than the inter­ spaces~ on the posterodorsal slope. LS.:\.:\[. no. 76704. Genus SOLYMA Conrad Conrad~::t>o in 1870. described the genus Solyma from near Haddonfield, New Jer· sey. a locality which was later correlated with the \Yoodbury claY, the second for· mation aboYe the -base-of the Matawan ~1Conrad. T. A., Amer. Jour. Conch., ,·ol. 6, p. 75, 1870. Invertebrate Fossils of the Navarro Group group. The horizon of the type locality is therefore low in the Exogyra ponderosa zone, corresponding in age to the lower part of the Taylor marl of Texas. The genus is based on the ipecies Solyma lineolaJ,us Conrad. Whitfield,261 in 1885, placed the genus under the family Solenidae, as did also Weller2R:! in 1907. Gardner263 in 1916, referred the genus to the Psammobiidae. The genus appears to me to be rather far removed from both the Solenidae and the Psammobiidae, and in form, internal characters, and hinge characters, to be closely related to Tellina and Linearia in the family Tellinidae. Anatina elliptica Gabb264 from Mullica Hill, New Jersey, appears to be a member of this genus. SOLYMA GARDNERAE Stephenson, n.sp. Pl. 43, figs. 6, 7 1916. Solyma lineolata Conrad. Gardner, Mary­land Geol. Survey, Upper Cretaceous (2 vols.), p. 701, pl. 36, figs. 20, 21. On part.) Shell thin, subovate in outline, de­ pressed convex, inequilateral, subequi­valve. Beaks nonprominent, broad, in­curved, prosogyrate, approximate, situated two-fifths the length of the shell from the anterior extremity. A faint umbonal ridge extends to the lower posterior extremity; the most inflated part of the shell is above the midheight and about at the midlength. The posterior part of the shell is higher than the anterior part. The shell is bent very slightly to the left posteriorly, and is slightly gaping both anteriorly and posteriorly. The hinge is not exposed on the only two Texas specimens available for study. The type spedes of the genus, Solyma lineolatus Conrad, from Haddon­field, New Jersey, shows in the right valve • 1Wbitfield, R. P., U. S. Geol. Sun·cy Mon., vol. 9, p. 182, 1885. -Weller, Stuart, Geol. Survey New Jersey, Paleontology, YO}. 4, p. 629, 1907. -Cardner, Julia A., Maryland Geol. 5urvey, Upper Cretaceous (2 vole.), p. 701, 1916. • Gabb, W. M., Acad. ~at. Sci. Philadelphia Proc., vol. 13, p. 324, 1861. two nearly vertical, sharply defined cardinal teeth, convex forward in trend, separated by a deep, narrow curved socket. Lunule narrow, excavated, bor­dered by a sharp, slight! y overhanging carina; the left side is broader than the right. Escutcheon long, narrow, exca­vated, outlined by sharp, bordering edges. Ligamental groove narrow, deep, extend­ing back more than half the length of the posterodorsal margin. Pallial sinus, as faintly discernible on the internal mold, wide, profound, broadly rounded on the inner end. The antero-and posterodorsal margins slope gently away from the beaks at a very broad, obtuse angle; anterior margin sharply rounded; ventral margin very broadly rounded, nearly straight cen­trally; posterior margin subtruncated, subangular both above and below. Sur­face marked by fine growth lines and by gentle, irregularly spaced growth undula­tions. No radiating sculpture appears on the outer shell surface, but the internal mold exhibits faint radiating lines. Dimensions of the holotype: Length 27.8 mm., height 17.6 mm., thickness 9 mm. Doctor Gardner identified the Chatfield specimen as Solyma lineolatus Conrad, and figured it as an example of that species. Although there is a close similar­ity in form between the Chatfield and Haddonfield shells, the former is propor­tionately less elongated and its beaks appear to be less prominent, and situated farther forward on the dorsal margin. In view of the difference in stratigraphic po­sition, and the wide geographic separation of the two localities, it seems reasonable to regard the Texas shell as specifically dis­tinct. One internal mold from the Ney­landville marl near Cooper, Delta County, is questionably referred to this species. Types.-Holotype, U.S.N.M. no. 21048; 1 unfigured paratype, U .S.N .M. no. 76705. Named in honor of Dr. Julia Gardner. Distribution in Texas.-Navarro group, Neylandville marl: ?Y2 mile north of Cooper (14062). Navarro group, Nacatoch sand: Vicin­ity of Chatfield ( 762, type loc.) . The Unfrersity of Te~ras Publication No. 4101 SOLYMA? PARVA Stephenson, n.sp. Pl. ·13, fig~. 18, 19 Shell small. thin. subovate in outline, moderateh· conYex. inequilateral, equi­rnlve. l\fost inflated aboYe the midheight and a little Lack of the midlength: pos­tf'rior slope steeper than anterior slope; posterodorsal slope stPep. Beaks mod­erate!y prominent, incurved, prosogyrate, approximate, situated slightly back of the midlength. Hinge not uncovered. Ad­ductor scars and pallial line obscure on the mold. I\umerous faint radiating lines appear on the mold; they are broadly cun·ed in trend, with the concavity toward the front. Anterodorsal margin sloping, nearly straight; anterior m:.iq:dn sharply rounded above the midheight; ventral margm broadly rounded, fullest an­terior!~-: po5terior rnargi n less sharply rounded than the anterior, rounding above into the broadly arched posterodorsal margm. Surface marked by 13 or 14 con­centric, round-topped. regularly spaced ridges or undulations, which are narrower than the interspaces, and tend to smooth r.ut toward the ventral margin. Dimensions of the holotvpe. an internal mold of hoth vah-es. with a little shell material adherin~ in the umbonal region: Len~th 9.5 mm.. height 6.5 mm.. thickness :i.8 mm. There are on] y two specimens of this ~pccies, the holotypf'. and the internal mold of a right rnh·e with some shell matefi al adht=>ri ng. Tlw generic relations ('annot he detC'rmined from these speci­mens. but th~=-re is a sug~estion of a pair of cardinal tt·eth bdow the beak on the frail. incom1>letPlY um·ovc>red hinrre of the • t:' riµht rnln·. resembling the teeth of Solrm a. Types.-·-·-Holotypc', C.S.\'.~VI. no. 76706: unfigurPd paratq>l'. U.S.\".~'1. no. 76707. /)ist rihu tion in Te:ras.-\'a\"arro group, \aC'atod1 ~and: Vic in it~· of Chatfield 17(>2 I. Superfamily SOLENACEA Family SOLENIDAE Genus LEPTOSOLEN Conrad LEPTOSOLEN BIPLICATUS Conrad Pl. 43, figs. 4, 5 1858. Siliquaria biplicata Conrad, Acad. Nat, Sci. Philadc:-lphia Jour., 2d ser., vol. 3, p. 324, pl. 34, fig. 17. 1867. Leptosolen biplicata Conrad, Am. Jour. Conch., vol. 3, pp. 15, 188. 1868. Leptosolen biplicatus Conrad. Conrad, in Cook, Geology of New Jersey, p. 727. 1885. Leptosolen biplicata Conrad. Whitfield, U. S. Geol. Survey Mon., vol. 9, p. 183, pl. 25, figs. l, 2. ( Geol. Survey New Jersey, Paleontology, vol. 1, p. 183, pl. 25, figs. 1, 2, 1886.) 1905. Leptosolen biplicata Conrad. Johnson, Arad. Nat. Sci. Philadelphia Proc., vol. 57, p. 17. 1907. Leptosolen biplicata Conrad. Weller, Geol. Survey New 1ersey, Paleontology, vol. 4, p. 624, pl. 70, figs. 30, 31. 1916. Leptosolen biplicata Conrad. Gardner, 1\laryland Geol. Survey, Upper Creta· ceous (2 vols.), p. 703, pl. 42, figs. 7, 8. 1923. Leptosolen biplicatus Conrad. Stephenson, North Carolina Geol. and Econ. Survey, vol. 5, pt. 1, p. 332, pl. 85, figs. 10-13. 1926. Lcptosolen biplicata Conrad. Wade, U.S. Geol. Survey Prof. Paper 137, p. 94, pl. 31, figs. 4, 7. Shell thin, greatly elongated, suhrec· tangular in outline, inequilateral, equi· valve, moderately and evenly convex from the longitude of the beak backward to the extremity, thus producing a wide open gape at the posterior extremity, com· pressed and less widely gaping at the anterior extremity; the greatest ventricos· ity is above midheight, which causes the shell to round down sharply to the dorsal margin; a low, broadly rounded swell exte~ds from the beak to the lower anterior extremity, and is bordered on either side by a broad, shallow sulcus; there is a sug· g~stion of a very broad, very shallow, widely flaring depression extending from the beak backward and downward to the ventral margin. Beaks small, low, non· projecting. incurved, slight!y prosogyrate, situated 0.25 to 0.28 the length of the shell from the anterior extremity. There is a slight, broad swell of the umbonal region aboYe the level of the dorsal margin. Hinge of left valve, as seen in well pre­served shells from the type locality on Invertebrate Fossils of the Navarro Group Owl Creek in Tippah County, Mississippi, with one paddle-like cardinal tooth which stands out prominently from the hinge line; the front side of this paddle is nearly vertical, though sloping slightly backward, and the back side is supported by a calcareous buttress or prop. Hinge of right valve with one prominent cardinal tooth similar to that in the left valve, with, however, its flat surface facing posteriorly and its supporting buttress on the front side; when the two valves are joined the flat surface of the right and left valves oppose each other. Ligamental groove narrow, deep, extending about one-third the distance to the posterior end of the hinge line. Nymph narrow and thin-edged but standing up prominently. A prom­inent internal rib or callosity extends from below the beak downward and slightly backward, fading out toward the ventral margin; a thin platform extends obliquely backward and upward from the dorsal end of this rib and is fused against the under side of the hinge plate, producing a deep recess under the platform at the upper end of the rib. Anterior adductor scar rather large, subtrigonal, situated just in front of the internal rib; posterior ad­ductor small, distant, subovate. Pallial line high above the ventral margin, con­necting the lower margins of the two ad­ductor scars. Anterodorsal margin short, broadlv arched; anterior margin subtruncated, obtusely subangular above and below; ventral margin long, straight, rounding up broadly in front, and more sharply be­hind; posterior margin subtruncated, rounding rather evenly into the margins above and below; posterodorsal margin long, straight. Surface divided rather sharply into two suhequal areas along a line extending from the beak, backward and downward to the lower posterior extremity; in front of the separating line the surface is marked only by fine concentric growth lines which are a little more sharply defined anter­iorly; back of the separating line the surface presents flatly compressed, over­lapping, concentric lamellae whose edges are somewhat irregularly spaced half a millimeter to 2 mm. apart; faintly devel­oped radial lines may be detected on the anterior portion of some individuals, especially on the radial swell which ex­tends from the beak to the lower anterior extremity. Dimensions of the left valve shown in plate 43, figure 4: Length 54 mm., height 19 mm., convexity about 5 mm. The Texas representatives of this species exhibit some variation in form with a tendency toward a slightly greater height in proportion to the length than is shown by typical shells from Mississippi, but the difference does not appear to be either pronounced or constant enough to justify their specific or varietal separation. The species is of common occurrence in the Navarro group and its equivalents in the Atlantic and Gulf Coastal Plain. Types.-Holotype, Academy of Natural Sciences of Philadelphia; from the Owl Creek formation. Topotypes are in the collections of the U.S. National Museum, U.S.N.M. no. 21170. Two plesiotypes from Texas, U.S.N.M. no. 76708. Distribution in Texas.-Navarro group. Neylandville marl: 21/2 miles north of Corbet (17365). Navarro group, Nacatoch sand: Vicinity of Kaufman (761) ; field 3/5 mile west of Kaufman (14103) ; field 2 miles south­west of Kaufman (7547); road 2 miles southwest of Kaufman (7546) ; vicinity of Chatfield (762) ; field south of Chatfield ( 7569) ; 3 miles northeast of Corsicana (9545); north edge of Corsicana (518); vicinity of Corsicana (763, 2 specimens figured) ; road 5 miles south-southwest of Corsicana (7573) . Navarro group, Kemp clay: 3~,~ miles northwest of Bazette (12922); 4V2 miles northwest of Lockhart (15528) . Outside distribution.-Arkansas: Naca­toch sand. Tennessee: Coon Creek tongue of Ripley formation. Mississippi: Ripley formation, and Owl Creek formation. East-central Alabama and Chatta­ hoochee region (Alabama-Georgia) : Eutaw formation, Blufftown formation, Cusseta sand, Ripley formation (upper part), and Providence sand. The Unii-crsity of Te.ras Publication No. 4101 l\orth Carolina: Snow Hill mf'mher of Black Creek formation and Peedf'e forma­tion (upper part). :Maryland: 1\Ionmouth formation. 1'ew. Jersey: Magothy formation. MerchantYillf' clay. 'VoodburY claY. Wen­onah sand. l\awsh1k marl. a1.1d H~d Bank sand. . Range.--In Texas the ~pecic~ has not been found below the \ayarro p:roup. but in the Atlantic and ea~tern Gulf Coastal Plain the range is reported to be through the zones of Exogyra ponderosa and E. costata~ that is. throup:h the equiYalents of the upper Austin chalk. the Tador marl, and the :\aYarro group. . LEPTOSOLEN? QUADRILATERUS Stephenson, n.sp. Pl. 43, fig. 1 Shell small. thin, greatly elongated, moderately ronYex~ strongly inequilateral, equirnlw~ widel~· gaping posteriorly, probably slightly gaping anteriorly; anterio: slopP short and steep: greatt"st conn·x1ty a little above the midheight, from which the shell rounds owr rather sharply to the posterodorsal margin. and more genth-down to the Yentral marain. L • ~ Beaks small. nonprominent. poorly pre­sen·ed in the holotype. situated about 2 mm. haC'k of the anterior extremity. Hinge not um·oyered. Intt>rnal features obscure with the exception of the ~tronp:. yertical rib. the deep impre~sion of which on the internal mold extends downward from the beak to the n·ntral margin near the an­terior extremit\·. The anterior marain . ~ rounds regularly up to the beak. and rather sharply down into the Yentral mar­gin; Yentral margin not completely pre­serYed. hut appart>nth· nt>arh· s~rai(Tht . . ~ ' perhaps ,.t>ry broadly conYex: posterior marp:in squarely truncate. subangular abo~·e. anp:ularly spaced~ sharp-edged growth lanwIIa e. Dimensions of the holotype~ a right rnh·e: Length l -L6 mm.• height 5.9 mm., conn~xity about l.5 mm. One specimen only of this species is a\·ai lable. Leptosolen elongata '\\'e ller:?65 ;:-.;:."· .. Iler. Stuart. G,.,,l_ Surwv :\f'w }C'r,:t>y. Paleontology, \(ll. I. l'· (1~:-. p!. :'ti. ti;.:~. 2:-. ::s. 1907. is a closely related species, but the Texas species appears to be more slender and more squarely truncate. IIolotype.----lJ.S.N.M. no. 76709. Distribution £'fl Tcxas.-Navarro group, Nacatoch sand: Vicinity of Kaufman (761). LEPTOSOLEN? LINGULIFORMIS Stephenson, n.sp. Pl. 43, fig. 3 Shell rather small, subrectangular in outline, greatly elongated, depressed con­vex, strongly inequilateral, probably equi­valve. Beaks small, nonprominent, slightly incurved, situated about 0.15 the length of the shell from the anterior ex­tremity. Hinge not preserved. The im­print of a nearly vertical internal rib may be seen extending from the beak downward nearly to the ventral margin. Other internal characters not preserved. The anterior margin is rather sharply but regularly rounded; ventral margin long and nearly straight, but swelling slightly downward; posterior margin subtruncated nearly vertically, rounding sharply into the Yentral margin, and less sharply into the dorsal margin above; posterodorsal margin long, broadly arched. Surface with only fine incremental lines. Dimensions of the holotype, the imprint of a right valve: Length 19.3 mm., height about 9 mm., convexity about 1.5 mm. This species is represented by one im· print only. Compared with Leptosolen qua.dri I aJerus it is proportionately higher, the Yentral and dorsal margins are not so straight, and the posterior margin is less squareIy truncated. Ho!otype.-U.S.N.M. no. 76710. Distribution in Texas.-Navarro group, Corsicana marl: 2 4/5 miles east of Cooledge (13832) . LEPTOSOLEN? LEVIS Stephenson, n.sp. Pl. 43, fig. 2 Shell small, moderately elongated, mod­erately convex, strongly inequilateral, equivalve, apparently gaping slightly posteriorly; umbonal ridge pronounced, subangular toward the beak, becoming weaker and rounding off toward the lower posterior extremity; anterior slope steep, greatest convexity above the midheight and Invertebrate Fossils of the Navarro Group a little back of the umbone; posterior slope long and gentle; posterodorsal slope steep. Beaks rather broad, strongly in­curved, prosogyrate, approximate, situated about one-sixth the length of the shell from the anterior extremity. Hinge not un­covered. On the internal mold the im­pression of a moderate I y strong internal rib extends from the beak downward and a little forward nearly to the ventral margin. Anterior margin rather sharply rounded at the midheight, rounding regularly up­ward to the beak and downward to the lower margin; ventral margin very broadly rounded, nearly straight centrally; pos­terior margin subangular low down toward the terminus of the ventral margin, broad Iy subtruncated above, inclined a little for­ward, meeting the margin above at a subobtuse angle; posterodorsal margin long, nearly straight anteriorly, becoming broadly arched posteriorly. Surface as shown by the mold nearly smooth, with the exception of gentle, irregular growth undulations. Dimensions of the holotype, a right valve: Length 13.3 mm., height 6.5 mm., convexity about 2.5 mm. The species is based on two internal molds of right valves and an internal mold of a left valve. Leptosolen? terminalis Weller,266 from the Merchantsville clay marl, near Jamesburg, New Jersey, is a similar species but appears to be less broadly truncated posteriorly, and the pos­!erior margin round~ much more broadly mto the dorsal margm. These differences and. !he markedly different stratigraphic pos1hon of the Texas material justify its specific separation. The form of this species is so markedly different from the typical Leptosolen that its generic identity may he reasonably doubted. Types.-Holotype, U.S.N.M. no. 76711; 1 unfigured paratype, U.S.N.M. no. 76712; 1 unfigured paratype, U.S.N.M. no. 20970. Distribution in T exas.-Navarro group, Nacatoch sand: Vicinity of Kaufman ( 761, paratype); road 2 miles southwest of Kaufman (7546, paratype); 3/5 to 4/5 mile northeast of Chatfield (14117, holotype). -Weller, Stuart, Geol. Survey New Jersey, Paleontology, vol. 4, p. 626, pl. iO, 6,. 29, 1907. Superfamily MACTRACEA Family MACTRIDAE Genus CYMBOPHORA Gabb CYMBOPHORA SCABELLUM Stephenson, n.sp. Pl. 43, figs. 8, 9 Shell very thin, of moderate size, sub­trapezoidal in outline, moderately convex, inequilateral, equivalve; umbonal ridge distinct, extending to the lower posterior extremity; anterodorsal margin steep, rounded; posterodorsal margin less steep, bending downward, slightly and broadly excavated between the umbonal ridge and the margin. Beaks moderate! y prominent, rather broad, incurved, slightly prosoay­rate, approximate, situated about 2/5 the length of the shell from the anterior ex­tremity. Hinge not uncovered. Ligament internal. Adductor scars only faintly im­pressed on the internal mold, but appar­ently small, subovate, situated above the midheight. Pallial line faint, but the pallial sinus, which is fairly distinct on the internal mold, is wide open behind, broadIy rounded in front, extending to about midway of the length below the midheight. Anterodorsal margin descend­ing, nearly straight in front of the beak rounding broadly into the rather sharpl~ rounded anterior margin; ventral margin very broadIy rounded, nearly straight centrally; posterior margin subangular below, subtruncated above, inclined for­ward, rounding broadly into the dorsal margin; posterodorsal margin broadly arched, somewhat inclined. Surface marked by fine incremental lines which show some irregularity in strength of de­velopment; well preserved shells show regular, very fine, closely spaced, con­centric ribs on the umbone. Dimensions of the holotype, a left valve shown in Plate 43, figure 8: Lenoth 27 mm., height 18 mm., convexity abgut 5.5 mm. This shell occurs abundant! y in the Nacatoch sand. It is proportionately less elongated than Cymbophora appressa Gabb from the Providence sand (marine facies) on Pataula Creek, Clay County, Georgia; it is also more inflated and is broader pos­teriorly in the direction of the heiaht than ' b Gabb s species. The Unfrersity of Te~ra.s Publication No. 4101 The specimens fi~tired hy Weller~1'7 under the name Schi:odcsma appressa Gabb~ from the Wenonah ~and of \ew Jersey (his figs. l-l-16, 201. appear to he more coarsely sculptured. and to haYe narrower and more prominent umbones than the Texas shells. The internal mold from the Cliffwood clay this fi~. 20) re­sembles the Texas shells in form except that the posterior truncation is more 1warly wrtical. It is doubtful if these stratigraph­ically lower and older shells are specifi­cally identified with those from Texas. Of the .two specimens from Tc>xas which he figured (figs. 17, 18. and 19) . one l fig. 19'l is here regarded as belonging to Cym bo phora scabel lu m; the other is treated as a new species, Cymbophora subtilis. Types.-Holotype. U.S.N.M. no. 7(>713; 1 figured paratype~ U.S.N.l\L no. 7671 :t; 1 unfigured paratype. U.S.N.l\tl. no. 2105-t Distribution in Texas.-~ayarro group, Nacatoch sand: Vicinity of Kaufman ( 761) : road 3 ·5 mile \\:est of Kaufman ( 754-5, 12923. 1-1098 l ; field 3, 5 mile wc>st of Kaufman ll-1103, type loc.) : field 2 miles southwest of Kaufman (75-l 7'1 : road 2 miles southwest of Kaufman (754-6, l ·W99) ; Yicinity of Chatfield l 762) ; field south of Chatfield (7569) ; 2 miles north of Corsicana l 955-l) ; Yicinity of Corsicana ( 763) ; road 5 miles south-southwest of Corsicana (7573 I; 2~~ miles north of Corsicana (] .iJ l ·l.) CYMBOPHORA SUBTILIS Stephenson, n.sp. Pl. 43, fig. 11 1907. Schi:.odcsma appressa Gabb. \Veller, Geol. Surwy l't•w .ler!"t>y. Paleontology. vol. 4, p. 6:)-!. pl. 11. fig~. 17. 18 (not fig~. U­16, 19-~l). Shell wry thin, of moderate size, sub­trigonal in outline. moderately convex, inequilateraL equirnhe; umbo.nal ridge distinct. but not pronounced; anterodorsal margin steep. a little excarnted near the margin back of the beaks: posterodorsal slope less stet>p. excarnted slightly between the umbonal ridge and the margin. The species exhibits considerable indiYidual Yariation in form and outline. Cmbonal region ratlwr narrow. Beaks prominent, ~r.W,·ll1· r. Stuart. G1'<•l. Surwy :\Pw Jer~ey, Paleontology, \Ol. -l, J'• 6Jl. fil!'"· }l-16, 20, }907, incurved. slightly prosogyrate, approxi­matc-, situated slightly in advance of the midlength. Hinge not uncovered. Liga­ment i nt<'rna I. PaII ia l sinus low, relatively narrow, horizontal. broadly rounded in front, scarcely extending to .the midlength. Anterodorsal margin slightly arched; an­terior margin rather sharply rounded; ventral margin broadly rounded, becoming nearly straight posteriorly; posterior mar· gin sharply rounded below with a sugges· tion of a subtruncation above, which in­clines forward; posterodorsal margin gently arched. The surface presents fine, closely packed, fairly regular, concen­tric ridges lvhich tend to become a little coarser toward the margins. Dimensions of the holotype, a nearly complete internal mold with some shell material adhering: Length 20.5 mm., height l 5 mm., thickness 8.5 mm. Compared with C_ymhophora scabellum, this species is shurtt"'r, has narrower, more pointed, and prominent beaks, and is more sharply pointed posteriorly. The species is similar in form to the specimens from the '\Venonah sand of New Jersey, figured by Weller under the name Schizodesma a.ppressa Gabb (his figs. 14-16, 20), but the sculpture of the Texas specimens ap­pears to be much finer. The different individuals exhibit considerable variation in form and the longer ones are separable with difficulty from the shorter variations of Cymbophora scabellwn. The few specimens from the Neyland· ville marl are all smaller than the adults in the Nacatoch sand, but appear to be ~ndistinguishable from the younger stages m that formation. This species is more finely sculptured than the shell from Coon Creek, Tennessee, described by \Vade~Gs under the name C. gracilis (Meek and Hayden). The Texas species, although closeiy related to Meek ~nd Hayden's species, is specifically dis· tmct. Types.-Holotype, U.S.N.M. no. 76715; this specimen was figured by Weller under the name Schi:.odes1na appressa Gabb. (?ee synonymy.) Ten unfigured paratypes, U.S.N.M. no. 76716. One unfigured para. type selected for pallial sinus U.S.N.M. ~6-1-' no. ' i '. !!llS\\"ade, Brue<>. r. S. Geol. Survey Prof. Paper 137, P• 98, pl. 31 , fig. 8, 1926. Invertebrate Fossils of the Navarro Group Distribution in Texas.-Navarro group, Neylandville marl: 31h miles west-north­west of Corsicana ( 16166) ; Corsicana road, 21h miles due north of Corbet ( 16170) ; 1h mile north of Cooper (14062). Navarro group, N acatoch sand: Vicinity of Kaufman ( 761, loc. of holotype and 10 paratypes} ; road 3/5 mile west of Kauf­man (7545, 12923, 14098); field 3/5 mile west of Kaufman ( 14103, locality of 1 paratype) ; road 2 miles southwest of Kaufman ( 7546} ; field 2 miles southwest of Kaufman (7547); 3 miles northeast of Corsicana (9545); north of Rock Branch, 3 miles northeast of Corsicana ( 9560) ; 2% miles north of Corsicana ( 14114) ; vicinity of Corsicana ( 763) ; road 5 miles south-southwest of Corsicana (7573) ; 4 miles north of Corsicana ( 17366) . Navarro group, Kemp clay: ?4 miles southeast of Zorn ( 10877) . Range.-The species as recognized ranges from the Neylandville marl through the Nacatoch sand and questionably into the Kemp clay. CYMBOPHORA CANCELLOSA Stephenson. n.sp. Pl. 43, figs. 13-15 Shell of moderate size and thickness, subtrigonal in outline, moderately convex, slightly inequilateral, equivalve; umbonal ridge obscure; dorsal slopes steep, the an­terior one a little excavated in front of the beak, the posterior one rounded. Beaks prominent, incurved, slightly prosogyrate, approximate, situated subcentrally. Hinge not uncovered. Under each beak is a tri­angular slit which extends obliquely back­ward to the margin. Adductor scars as impressed on internal mold, subequal, sub­ovate, of moderate size. Pallial line obscure; pallial sinus distinctly impressed on some internal molds, narrow, ascending, sharply rounded in front, extending nearly to the midlength and midheight. Antero­dorsal margin descending with moderate steepness, slightly arched; anterior margin sharply rounded at about the midheight; ventral margin broadly and evenly rounded; posterior margin a little less sharply rounded than the anterior; postero­dorsal margin rather steep, broadly arched. The surface is compactly ornamented with distinct concentric ribs; toward the beaks these ribs are quite small, are separated by mere thread-like lines, and numlwr B to 12 or more to the millimeter; from the beaks outward the ribs increase regularly in size until near the margin they num­ber only about 2 to the millimeter; with increasing distance from the beaks the interspaces widen out gradually until near the margin they are wider than the ribs, and several fine growth lines can be seen in each of them on well preserved surfaces; though the ribs are all somewhat rounded on their crests they show a tendency to become a little more angular toward the margin. The ribs cover all the surface except a narrow, radiating band on the obscure umbonal ridge, which is smooth except for growth lines and, on some speci­mens, 2 or 3 very obscure radiating lines. On the dorsal slopes the ribs are coarser and less numerous than they are on the main shell surface; one of these larger ribs represents 2 or 3 of the smaller ribs; the line of separation between the two types of ribbing is marked on the anterodorsal slope by an impressed, fairly distinct line, and on the posterodorsal slope by the smoother band on the umbonal ridge. Dimensions of the holotype, a left valve which is slightly flattened and elongated by mechanical pressure: Length 25 mm., height 17.8 mm., convexity 5.5 mm. This species has in the past been con­fused with Cymbophora lintea (Conrad). The type of Conrad's species was found in the Ripley formation at Eufaula, Ala­bama,269 and should be preserved in the Academy of Natural Sciences of Phila­delphia, but it is apparently lost. Com­pared with Conrad's original figure, the Texas species appears to average larger in size, is more coarsely sculptured, and lacks a radiating, shallow depression extending from the beak to the ventral margin just in front of the umbonal ridge. Compared with C. trigonal is Stephenson, a closely related species from the Snow Hill member of the Black Creek formation of North Carolina, the Texas species has slightly coarser concentric sculpture, with interspaces not so deep, and the ornamen­tation is well developed nearly to the beak. The species is less elongated, more 200Conrad, T. A., A.cad. Nat. Sci. Philadelphia Jour., .2J ser., vol. 'i, p. 278, pl. 46, fig. 17, 1860. The Unil'ersity of Te.ras Publication No. 4101 trigonal in outlirn~. and more coarsPlY seulptur<'d. than eitlwr C. scaht,l!um or (:. su btilis. The narrow a~('endin~ paIIiaI sinus is also a distinguishing feature of this specie~. Types.-Holotype. C.S.:\.:\I. no. 76718; 1 figured paratype~ LS.:\.:\I. no. 76719: 1-1 selected unfigured paratypes, li.S.N.M. no. 76720. Distribution in Texas.-:\a,·arro group. :\acatoch sand: Loose pieces of rock in street at Chatfield l 7568) : 2 miles north of Corsicana l855-1. 9557); 21 ~ miles north of Corsicana l 1-H 1-l l : vicinitv of Corsicana l 763, 1 paratype figured) ; north edge of Corsicana l 518, loc. of holo­type and 1-l selected paratypes) ; road 5 miles south-southwest of Corsicana (7573). :\"arnrro group, Kemp clay: ?Brazos RiYeL 2 miles above l\Iilam County Iine ( 13776). ­ Range.-:\acatoch sand. questionably ranging upward into the Kemp clay, of the :\avarro group. CYMBOPHORA BERRYI Gardner Pl. 43, fig. 10 1916. Spisula (Cymbophora) berryi Gardner, :\laryland Geol. Survey, Cpper Creta­ ceous (2 vols.), p. 708, pl. 43, figs. 2, 3. Shell of moderate size and thickness, hm·ing a trigonal form closely similar in outline and degree of inflation to that of C. cancellosa. The species differs from C. cancellosa chiefh-in its smoother surface features. It is ~narked on the main part of the shell by irregular growth lines, low ridges, and gentle undulations, which tend to become a little coarser toward the margin. On the dorsal slopes the concen­tric sculpture appears as regular ridges much coarser than the growth markings of the main part of the shell, and in the wider interspaces are fine growth lines; on the umbonal ridge is a roughened, radial, slightly impressed band set off bv obscure marginal line~. ha,·ing a maxim~m width of about 3 mm.: a distinctly impressed line or sukus separates the sculpture of the anterodorsal slope from that of the main shell. The triangular marginal slit below the beak is sharply defined and well pre­served. Dimensions of the figured shell from Texas: Length 22 mm.~ height 16.4 mm., l'Onn·xit y 5.5 mm. The f~gurt'd sp<"'cimen from Texas has heen compared with the type of C. berryi Gardner. from the l\Ionmouth formation at Brightse~t. Prince Georges County, Mary· land. and no basis can be detected for a specific separation. Holotype.-The holotype is on deposit in the r .S. National l\Iuseum. Plesiotype from Texas, U .S.N .M. no. 76721. Distribution in Texas.-Navarro group, Nacatoch sand: Vicinity of Kaufman (761, figured) ; northeast of Quinlan (16162). Outside distribution.-:Maryland: Mon· mouth formation. Range.-Nacatoch sand of the Navarro group. Outside of Texas recorded only from the l\Ionmouth formation (Exogyra costala zone) in Maryland. CYMBOPHORA INFLATA Stephenson, n.sp. Pl. 43, figs. 16, 17 Shell large, subtrigonal, rather strongly inflated~ inequilateral. The shell has suf· fered a slight mechanical flattening in the mnbonal region~ but the greatest inflation appears to be a little above the midheight and slightly back of the midlength, from which point the surface rounds down regularh-toward the ventral and anterior L • margins: the umbonal ridge is expressed by a faint subobtuse angulation where the surface of the main disk joins the postero· dorsal slope; the anterodorsal slope is steep and becomes marked!y excavated toward the beak: the posterodorsal slope is steep and broadly arched, and becomes slightly excavated toward the beak; it is traversed by a very faint radial ridge a few millimeters behind the umbonal ridge. The available material includes the in· ternal and external molds of one large incomplete left vah-e ~ none of the shell substance is presen·ed. Beaks prominent, strong!y incurwd, prosogyrate, situated slightly in adrnnce of the midlength. The hinge and internal features are not clearly exposed~ but the form of the shell is such as to justify referring it to Cymbophora. Anterodorsal margin apparently very broadly arched: anterior margin sharply rounded: wntral margin broadly rounded; Invertebrate Fossils of the Navarro Group poeterior margin subangular below at the end of the umbonal ridge, subtruncated above this angulation, rounding above into the broadly arched posterodorsal mar­gin. Surface nearly smooth, apparently marked only by growth lines and slight undulations, which, however, become no­ticeably coarser on the posterodorsal slope. Approximate dimensions of the holo­type: Length 73 mm., height 62 mm., con­vexity 19 mm. Holotype.-U.S.N.M. no. 76722. Dutribution in Texas.-Navarro group, Nacatoch sand: 1% miles northeast of Quinlan (16162). CYMBOPHORA1 SIMPSONENSIS Stephenaoa. a.ap. Pl. 43, fig. 12 Shell rather large, elongated, subelli p­tical in outline, moderately convex, in­equilateral, probably equivalve; greatest inflation above the midheight, in front of the midlength, slightly back of the beak; anterodorsal slope moderately steep, rounded; umbonal ridge distinct, obtusely angular, extending to the lower end of the posterior truncation; postero­donal slope divided into two flattish to slightly excavated radial bands expanding outwardly, by a ridge similar to the umbonal ridge, extending from the beak to the upper end of the posterior trunca­tion. Beaks broad, incurved, strongly prosogyrate, approximate, situated about one-fourth the length of the shell from the anterior extremity. Hinge not suf­ficiently uncovered for description. Ad­ductor scars obscure. Pallial sinus faint but discernible on the mold; it is wide, abort, and broadly rounded in front, and is similar to that of Cymbophora scabel­lam, though more ascending. The anterior margin is rather sharply rounded above the midheight, and rounds up regularly to the beak; ventral margin very broadly rounded centrally, curving up regularly in front, and toward the rear turning up more abruptly and becoming subtruncated below and in front of the end of the umbonal ridge; posterior margin subtrun­cated with a forward inclination; pos­terodorsal margin long, a little inclined, broadly arched. The internal mold re­flects gentle, irregular growth undulations, and fragments of the shell near the dorsal margin indicate a surf ace marked by fine, rather sharp growth ridges; the mold also reflects a faint radiating line extending from the beak to the front end of the posterobasal truncation. Dimensions of the holotype, the internal mold of a left valve: Length 36 mm., height 23 mm., convexity about 8 mm. Great longitudinal prolongation and the strongly prosogyrate character of the beaks characterize this species. In form it strongly resembles the genus Etea, but the pallial sinus and poorly preserved features along the dorsal margin indicate that it belongs elsewhere. It is question­ably ref erred to Cymbo phora. The avail­able material is hardly adequate for specific description, but there should he little difficulty in identifying well pre­served specimens of the same species from the type locality. Several poorly preserved specimens from the type locality appear to he pro­portionately still more elongated and flatter than the holotype, but are tenta­tively referred to the species because of the known individual variation of the members of this group. Fragments of shell adhering to these specimens indicate a nearly smooth shell with fine, rather sharp growth lines. Types.-Holotype, U.S.N. M. no. 76723; 3 unfigured paratypes, U .S.N .M. no. 76724. Distribution in T exas.-Navarro group, Nacatoch sand: Road 2 miles southwest of Kaufman (7546, type loc.); field south of Chatfield ( 7569) ; 3 /5 to 4,-i mile north­east of Chatfield (7572). Unidentified apeclmena of CYMBOPHORA A small imperfect right valve from the Corsicana marl in a branch below the public road, 2% miles north of Tona sid­ ing, in Hunt County (15546), is trigonal in form, in this respect resembling C. cancellosa, but the surf ace features are poorly preserved. U.S.N.M. no. 76725. Specimens of Cymbo phora have been ob­tained from the Kemp clay as indicated below. In the left bank of Colorado River at Webberville, Travis County (7601, U.S.N.M. no. 76726), a hadl~r crushed, elongated, nearly ~mooth ~hell exhibiting only fine growth lines. In a road ditch 3. '5 mile west of Elm Creek School, '1.% miles northwest of Lockhart (15528, U.S.N.M. no. 76727). three crushed, imperfect molds of a large species resembling Cymbophora. inflata, but too imperfect for identification; this species is trigonal in form, apparently smooth, and is probably not less than 70 mm. long and 60 mm. high. At the same locality (16151, U.S.N.M. no. 76728), a small trigonal species re$embling C. can­cellosa in size, form, and outline but with surface features obliterated; at the same locality (16151, U.S.N.M. no. 76729) is a poorly preserved specimen resembling C. appressa (Gabb) in outline, but ap­parently more inflated. Superfamily MY ACEA Family CORBULIDAE Genus CORBULA Lamarck CORBULA CRASSIPLICA Gabb Pl. 44, figs. 16, 17 1860. Corbula crassiplica Gabb, Acad. Nat. Sci. Philadelphia J our., 2d ser., vol. 4, p. 394, pl. 68, fig. 25. 1885. Corbula crassiplica Gabb. Whitfield, U.S. Geol. Survey l\fon., vol. 9, p. 178, pl. 23, fig. 30. 1907. Corbula crassiplica Gahb. Weller, Geol. Survey New Jersey, Paleontology, vol. 4, p. 641, pl. 72, figs. 27, 28. 1916. Curbula crassiplica Gahb. Gardner, Mary­land Geol. Survey, Upper Cretaceous (2 vols.), p. 713, pl. 43, figs. 6, 7. 1926. Corbula crassiplica Gahb. Wade, U.S.Geol. Survey Prof. Paper 137, p. 96, pl. 31, figs. 9, 13. Shell small, relatively thick, subtrigonal in outline, inequilateral, markedly inequi­valve, strongly convex anteriorly, sharply compressed posteriorly. Right valve strongly humped above the midheight, a little in front of the beak, anterodorsal slope very steep to overhanging; postero­dorsal slope Yery steep, overhanging and excavated; a sulcus separates the narrow, compressed posterior area from the main strongly ribbed surface. The left valve is much smaller and less inflated and fits well within the right valve whose margins arc strongly overlapping. Beak of right valve hroad, very prominent, strongly in· t·u n 1ed. overlHmgin~. slightly prosogyrate, situated about 2/ S the length of the shell from tlw anterior extremity. Beak of left valve nonprominent, incurved, slightly prosogyrate. situated slightly in advance of the mid length; the high, prominent overhanging beak of the right valve domi· nates the low beak of the left valve. Hinge of right valve with one prominent up· curved tooth below the beak, behind which is a wide, profound socket for the recep­tion of the condrophore of the left valve. In the Texas material the internal features are obscure and the hinge of the left valve was not observed. The anterodorsal margin of the right valve is arched and rounds downward into the rather sharply rounded anterior mar­gin; ventral margin broadly rounded be· coming a little concave just back of the posterior end; posterior margin squarely truncated, the truncation making almost a right angle with the ventral margin be­low, and an obtuse angle with the dorsal margin above; posterodorsal margin con· cave upward. The surface of the right valve appears to be smooth for about a millimeter outward from the beak, beyond which it becomes broken into strong, round-crested, concentric ribs; near the beak these ribs are small and may he a little crowded, but as a rule they quickly become larger and are separated by deep interspaces that vary from a little nar· rower to much wider than the ribs; these ribs are strongly developed all over the anterior and main surface of the shell, but end abruptly at the narrow, radiating sulcus just in front of the umbonal ridge; they show a slight uproll and vary in strength and width of inters pace and ex· hibit considerable individu3} variation. The slightly excavated, sinuous, posterior dorsal slope is ornamented with coarse growth lines which, toward the truncated term in us, break up into thin overlapping laminae which are generally poorly pre· served or become damaged as the matrix is separated from the shell. In contrast to the right valve the left valve lacks prom· inent concentric ribs and is ornamented only with coarse growth lines; it is strik­ingly different from the right valve and seen alone, might readily be taken for a separate species; it is set well down within the overlapping right valve. On the in­ner surface of the right valve between the end of the left valve and the posterior truncation is a ridge of irregular trend, approximately parallel to the truncation, with a sort of V-shaped projection toward the rear near the center. Dimensions of the right valve shown in plate 44, figure 16: Length 6 mm., height 4.6 mm., convexity about 2.5 mm. Some of the larger individuals attain as much as 8 mm. in length. The Texas shells have been compared with to po types from the Coon Creek tongue of the Ripley formation, in a cut of the Southern Railway %, mile west of Wenasoga, near the Tennessee State line, Alcorn County, Mississippi. Both the topotypes and the Texas shells exhibit considerable individual variation in the strength and spacing of their concentric ribs. Types.-The type material should be in the collection of the Academy of Natural Sciences of Philadelphia, but is missing there. Plesiotypes from Texas, U.S.N.M. no. 76730. Distribution in Texas.-Taylor marl: Small arroyo 2%, miles south of San Marcos, 1/3 mile east of San Marcos­Sta ples road, Hays County (7617) ~ Austin-Manor road, 1 15 mile east of Big Walnut Creek, Travis County (12893). Wolfe City sand member of Taylor marl: Cotton Belt Railroad (G.C.&S.F.) cast by north of Wolfe City, Hunt County, 1 mile (5325) , Ph miles ( 9710) , 2 miles (9709), and 24;5 miles (9708). Navarro group, Neylandville marl: 1h mile north of Cooper ( 4064, 5318, 7509, 14062) ; 21h miles northeast of Royce City (16157) ; 1 mile east of Gastonia (7550). Navarro group, Nacatoch sand: Vicin­ity of Kaufman (761) ; road 3/5 mile west of Kaufman ( 14098, plesiotypes) ; field 3/5 mile west of Kaufman (14103); road 2 miles southwest of Kaufman ( 7546) ; vicinity of Chatfield (762) ; field south of Chatfield ( 7569) ; %, mile east of Chat­field (7571) ; 3/ 5 to ~1> mile northeast of Chatfield {7572) . Navarro group, Corsicana marl: 5 miles southwest of Quinlan ( 15546) ; Onion Creek, 21h miles west of old Garfield (14049, 14156); 1/~ mile below Martin­dale (7621, 15527) ; 2 miles east of Marion (Tex. Bu. 2395) ; well 7 / 20 mile south by west of St. Mary's University, Bexar County ( 16353, 16408) . Navarro group, Kemp clay: 4 miles south of Manor (Tex. Bu. 2399) ; 2 miles north-northwest of Deatsville ( 14128) ; vicinity of Webberville (Hill coll. 8); near Deatsville (764, 14125) ; well near old Garfield ( 1641). Outside distribution.-Arkansas: Naca­toch sand. Tennessee: Coon Creek tongue of Ripley formation. Mississippi: Coffee sand and Ripley formation. Alabama: Blufftown formation. East-central Alabama and Chattahoochee region {Alabama-Georgia) : Blufftown formation, Ripley formation, and Provi­dence sand. Maryland: Monmouth formation. New Jersey: Merchantville clay, ~rood­bury clay, Wenonah sand, Navesink marl, and Red Bank sand. Range.-Ranges through the zones of Exogyra ponderosa and Exogyra costata in the Atlantic and Gulf Coastal Plain. CORBULA WILLIARDI Wade Pl. 44, fig. 14 1926. Corbula williardi Wade, U.S.Geol. Survey Prof. Paper 137, p. 97, pl. 31, figs. 17, 18. The species is represented in Texas by two right valves. These specimens, though small, are a little larger than the holotype; they are subtrigonal in outline, rather thick-shelled, and strongly ventri­cose; the greatest inflation is toward the front above the midheight; anterodorsal slope high, steep and slightly overhang­ing; umhonal ridge subangular, sinuous, bordered in front by a broad, shallow radial depression; a similar shallow radial depression occurs toward the front part of the shell; posterodorsal slope steep, forming an excavated, sinuou~, radial hand, bordered below hy the umhonal ridge and above by a round-crested ridge whose upper ~lope descends steeply to the dorsal margin. The holotype from T~n­nessee is only about 3.5 mm. long. Beak of right valve strongly prominent. strongly incurved, prosogyrate, situated at about the midlength. Hinge and internal fea­tures not uncovered. Posterodorsal mar­g:in slightly arched~ anterior margin sharply rou11ded; ventral margin broadly rounded centrally, becoming slightly con­cave toward each extremity; posterior margin truncated vertically, slightly con­cave, angulated at each end of the trun­cation; posterodorsal margin slightly concave. Main surface of right valve cov­ered with strong, round-crested, concentric ribs which are wider than the moderately deep inters paces; these ribs have a maxi­mum spacing of about 4 to the millimeter near the margin, but become progressively smaller toward the beak, practically dis­appearing before the tip of the beak is reached; the concentric ribs smooth out linearly as they cross the umbonal ridge, but reappear on the posterodorsal slope in smaller, more closely packed, and somewhat more irregular development. The left valve, as seen in the holotype, is smaller and less ventricose than the right valve, but is similarly sculptured. Dimensions of the specimen shown in plate 44, figure 14: Length 4.9 mm.;, height 3.9 mm., convexity about 1.5 mm. The right valve of Corbula williardi Wade is similar in its sculpture to that of C. crassiplica Gabb and to that of C. crassiplica navarroana Stephenson, but is smaller and much more finely marked; the strong sculpture of the left valve is in contrast to that of the smooth left valves of the species and variety named. This statement is based on the holotype, as no left Yah-es have been found in Texas. Corbula perbrevis Conrad, from North Carolina, is a larger, longer, and more coarse I y sculptured species. Types.-Holotype, U.S.N.M. no. 32816, from the Coon Creek tongue of the Ripley formation, Coon Creek, Dave Weeks' place, McNairy County, Tennessee. Plesio­type from Texas, U.S.N.M. no. 76731. JJistrilmtion z'.n Texas.-Navarro group, ]\ acalo<'h ~and: Vicinity of Kaufman ( 7frl. 1 spccimPn figured) ; 21h miles west by south of Corsicana ( 17368). Outs id e distribntion.-Tennessee: Coon Creek tongue of Ripley formation. Ra.nge.-Known only from the type locality in Tennessee, and from near Kaufn;an, Texas. The Coon Creek tongue is believed to be stratigraphically a little lower and older than the Nacatoch sand. CORBULA TORTA Stephenson, n.sp. Pl. 44, figs. 18-20 Right valve small, thick, subtrigonal in outline, strongly convex, inequilateral. The anterior part of the valve is swollen almost to overhanging at about the mid­height, and the anterodorsal slope is steep and overhanging; a broad radial depres· sion just back of the swollen portion ex· tends to the ventral margin; the strongest inflation is midway of the length and height; at about the midheight there is a sharp change to a steeper slope which curves strongI y down to the ventral mar· gin, suggesting a senile condition; the posterior end of the valve is sharply con· stricted. The posterodorsal slope is steep and forms a well defined, slightly exca· vated, sinuous band which twists sharply as it approaches the short, truncated, pos· terior extremity; laterally this band joins the main surface of the shell at a subangle forming a narrow, sinuous umbonal ridge. Anterodorsal margin arched; anterior margin sharply rounded; ventral margin broadly rounded and gently sinuous; posterior margin short and truncated; posterodorsal margin broadly excavated. Beak strongly incurved, situated slightly in advance of the midlength; it is slightly crushed but appears to be weakly prosogy· rate. Hinge and internal features not un· covered. As preserved the surface of the umbonal region is smooth; a little above the midheight very fine, concentric ribs appear and are followed below to the ventral margin by progressively stronger and coarser ribs which number 4 or 5 to the millimeter just above the margin; the Invertebrate Fossils of the Navarro Group ribs are broadly sinuous on the anterior half of the shell; they fade out posteriorly before reaching the umbonal ridge. Dimensions of the holotype: Length 5 mm., height 3.8 mm., convexity about 2.5 mm. The description is based on one right valve only. The species does not appear to he closely related to any described species, but bears some resemblance to Corbula wilUardi Wade; the posterodorsal area differs, however, in that it is sharply twisted upward as it approaches the posterior extremity. Holotype.-U.S.N.M. no. 76732. Distribution in Texas.-Navarro group, Neylandville marl: 2% miles north of Corbet (Tex. Bu. 17300). CORBULA ROCKENSIS Stephenaon, n.sp. Pl. 44, fig. 15 Shell small, moderately thick, subtrig­onal in outline, moderately elongated, in­equilateral, inequivalve, strongly convex. Anterodorsal slope high and overhanging; umbonal ridge angular, sinuous; postero­dorsal slope forming a steep, sinuous, slightly excavated band, bounded above by a crudely developed radial ridge with a steep, slightly excavated slope on the marginal side. The greatest inflation is toward the front and the posterior part becomes narrow and compressed. A broad, very shallow radial sulcation extends to the ventral margin just in front of the umbonal ridge. Beak of right valve broad, prom­inent, strongly inrolled, prosogyrate, sit­uated about 5 /8 the length of the shell from the anterior extremity. Hinge and internal features not uncovered. Antero­dorsal margin long, broadly arched, slightly inclined; anterior margin sharp I y rounded; ventral margin broadly rounded, slightly sinuous, becoming a little concave near the rear end; posterior margin squarely truncated, angular above and be­low; posterodorsal margin rather strongly concave. The surface is smooth near the beak, but at a distance of 2 or 3 mm. from the beak, becomes concentrically ribbed, at first finely so, passing progressively to stronger and coarser ribs toward the mar­gin. Very faint, fine, radial ribs can be detected in front of the umbonal ridge on the holotype, but these fade out within 2 or 3 mm. toward the front. Several left valves provisionally referred to this species are less inflated, more pointed posteriorly, and have similar concentric sculpture. Dimensions of the holotype, a right valve: Length 8 mm., height 5.5 mm., con· vexity 2.5 mm. Material from several localities identi­fied with this species show some individual variation in outline and sculpture; some specimens are proportionately shorter than the holotype, and some are less coarsely sculptured; faint radiating costae, like those in front of the umbonal ridge on the holotype, may be detected in a similar position on several other shells, but on others radial markings appear to be want­ing. This species is similar in form to Corbula subradiata texana, on both valves of which, however, radial markings are more strong I y developed, and concentric sculpture appears to be consistently finer. Types.-Holotype, U.S.N.M. no. 76733; I unfigured paratype, U.S.N.M. no. 76734. Distribution in Texas.-Navarro group, Neylandville marl: 21/2 miles north of Corbet (17365). Navarro group, Nacatoch sand: Vicinity of Chatfield ( 762) ; field south of Chatfield ( 7569) ; 3 miles northeast of Corsicana ( 9545, type loc.) ; vicinity of Corsicana (763) ; road 5 miles south-southwest of Corsicana (7573) ; 1 4/5 miles northeast of Quinlan (16162). Range.-Known only from the Ney land­ville marl and the N acatoch sand of the Navarro group. CORDULA SUBRADIATA TEXANA Stephenson, n.var. Pl. 44, figs. 21, 22 Shell small, moderately thick, subtrig­onal in outline, moderately convex, in­equilateral, inequivalve; greatest inflation about midway of the length, above the midheight; anterodorsal slope steep, rounded; umbonal ridge angular, slightly sinuous; on the right valve a broad, shal­low, radial depression lies just in front of the umbonal ridge and extends to the margin; posterodorsal slope of right valve forming a steep, sinuous, slight! y exca­vated band, bordered above by the margin of the shell; same slope of left valve similar but less sinuous and less excavated. The University of Texas Publication No. 4101 Beaks moderately prominent, incurved, slightly prosogyrate, situated a little back of the midlength. Hinge and internal features not uncovered. Anterodorsal margin broadly arched, rounding into the rather sharply rounded anterior margin; ventral margin broadly rounded, becoming nearly straight to slightly concave toward the distal end: posterior margin sharply truncated, the truncation sloping a little forward; posterodorsal margin slightly arched. Very faint, fine, rather closeIy spaced radiating lines formed by rows of microscopic punctations may be detected under strong magnification over most of the surface of the holotype. The lines on the forward part of the shell are finer than those farther back; the lines are obscure or wanti"ng on the dorsal slopes. This obscure radial ornamentation is present on left valves, but the strength of the lines is variable on different individuals. The con­centric sculpture of both valves is very fine, becoming smooth toward the beak. Dimensions of the holotype, a right valve: Length 7.6 mm., height 5.2 mm., convexity about 2.5 mm. Corbula subradiata Gardner,2 io from the Monmouth formation at Brightseat, Mary­land, is closely related to this Texas form, but it exhibits a less sinuous, smoother, posterodorsal area which is noticeably sub­divided by a minor radial ridge, and has still finer radial lines and punctations; the latter were not mentioned in the original description. The holotype, which is on deposit in the National Museum, is badly broken. The specimens from the Brooks estate near Seat Pleasant, Maryland, repre­sented by Gardner's figures 9-12, are more coarsely sculptured and appear to repre­sent a different species or variety. Types.-Holotype, U.S.N.M. no. 76735; 1 figured paratype, U.S.N.M. no. 76736; 1 unfigured paratype, U.S.N.M. no. 76737. Distribution.-Navarro group, Nacatoch sand: Vicinity of Chatfield (762) ; road 7% to 811~ miles north by east of Corsi­cana (7567) ; 3 miles northeast of Corsi­cana (9545, 1 paratype figured) ; vicinity of Corsicana (763) ; road 5 miles south­southwest of Corsicana (7573, loc. of holo­ :r.0cardnf'r, Julia. \laryland Geo!. Survq·, L'pper Cretace­ous 12 rn\,-.), p. 718. pl. ·H . figs. 13-15 (figs. 9-12), 1916. type and 1 unfigured paratype) ; 4 miles north of Corsicana (17366) . CORBULA LINTEROIDEA Stephenson, n.ap. Pl. 44, figs. 11-13 Shell small, moderate!y thick, subtrig· onal in outline, moderately convex, in. equilateral, slightly inequivalve; a broad! slight, radial swell extends to the lower anterior extremity; umbonal ridge sharply anO'ular. Main part of shell between the radial swell and the umbonal ridge slightly flattened, and the surface just in front of the lower end of the umbonal ridge is slightly excavated; posterodorsal slope steep, forming an excavated radial band which warps up to form a keel at the upper distal margin; on the right valve the upper margin of this band is bordered by a low carina which extends from the beak to the upper end of the posterior truncation; there is no corresponding ridge on the left valve. Left valve slightly overlapped and inclosed by the right valve. Beaks broad, flattened, incurved, prosogyrate, approxi· mate, situated a little in advance of the midlength. The hinge of one left valve is exposed and shows a flattened chondro· phore in front of which is a profound pit for the reception of the cardinal tooth of the right valve; the chondrophore is di­vided into two unequal parts by an im· pressed line or sulcus extending from the beak backward and downward to the inner margin; the posterior of the two parts is the smaller and narrower and distally sup· ports a small node or tooth. The anterior adductor scar is imperfectly preserved; the posterior adductor is subovate and of mod­erate size, is situated on an upraised plat· form, and is bordered along its forward side by an upraised rim or carina. The pallial sinus is very shallow, consisting of a nearly vertical line concave outward. Anterodorsal margin broadly arched; an· terior margin somewhat sharply rounded; ventral margin broadly rounded, her.om· ing slightly concave near the posterior end; posterior margin sharply angular to pointed below, subtruncated above with the truncation inclined strongly forward; posterodorsal margin slightly arched. The surface is ornamented with rather sharp, somewhat irregular concentric ridges, sep· arated by shallow, broader depressions. Invertebrate Fossils of the Navarro Group Radial lines are faintly observable in front of the umbonal ridge on both valves in a band about 1.5 mm. wide. Dimensions of the holotype, a shell with both valves attached: Length 6.5 mm., height about 4. 7 mm., thickness 3.2 mm. Compared with Corbula rockensis this species is less ventricose anteriorly, is less compressed posteriorly, is more finely aculptured, and is less squarely truncated posteriorly. This species contrasts with C. 1ubradi4ta texana in the absence of radial ribs with the exception of the faint lines in front of the umbonal ridge, and in having a more prominent, more sharply angular umbonal ridge. The Texas species lacb the well developed radial sculpture of C. subradiata Gardner, from the Mon­mouth formation of Maryland, and also lacks the broad, shallow, radial sulcus which extends all the way from the beak, to the ventral margin in front of the umhonal ridge in that species. C. woodi is more coarsely sculptured and has a less prominent umbonal ridge. All of the species compared belong to a closely re­lated group of Corbulas having radial 1CUlpture more or less clearly developed. Types.-Holotype, U.S.N.M. no. 76738; S unfigured paratypes, U .S.N .M. no. 76739. Di&tribution in Texas.-Navarro group, Nacatoch sand: Vicinity of Corsicana ( 763, type Ioc.) ; 2 miles north of Cor­sicana (9554); 4 miles north of Cor­sicana ( 17366) . CORBULA WOODI Stephenson, n.ap. Pl. 44, figs. 6, 7 The species is represented by 2 in­dividuals, one a young shell. Shell small, subovate in outline, moderately ventricose, inequilateral, inequivalve. The greatest inflation is about midway of the shell and a little above the midheight. The antero­dorsal slope overhangs the margin some­what, just in front of the beak. The an­terior of the shell slopes forward rather gradually, and the posterior is com­pressed. The posterodorsal slope of the left valve is strongly excavated by a radial depression as indicated on the in­ternal mold, while the corresponding slope of the right valve appears to be rather plump. The shell is broken away along the umbonal ridges, but an obtuse! y sub­angular, curved, somewhat sinuous ridge appears on the internal mold of the left valve. Beaks moderately prominent, the right one a little higher than the left, broad, incurved, approximate, slightly prosogyrate, situated about 0.55 the length of the shell from the anterior extremitv. Hinge not uncovered. Posterior adduct~r scar of moderate size, subcircular, situated high in the shell. Anterodorsal margin broadly arched; anterior margin sharply · rounded; ventral margin broad! y rounded; posterior margin with a short, square truncation; posterodorsal margin short, slightly concave. Surface marked by rather coarse, somewhat irregular, con­centric ridges, and by very faint radiating lines which can be seen on both valves. Dimensions of the holotype: Length 9.2 mm., height 6.5 mm., thickness 4.1 mm. Compared with C. rockensis the shell of this species is more regular, less humped and less ventricose posterioriy, and is not quite so coarsely sculptured; C. subradiata texana is more strongly humped, more finely sculptured, and has stronger radiating lines on the left valve; C. linteroUlea is much more finely sculp­tured, and has a sharper, more angular umbonal ridge. Types.-Holotype, U.S.N.M. no. 76740; 1 unfigured paratype, U.S.N.M. no. 7674.1. Named for the Hon. George T. Wood, Governor of Texas, 1847-1849. Distribution in Texas.-Navarro group, Nacatoch sand: Vicinity of Corsicana ( 763, loc. of holotype) ; 2 miles north of Corsicana ( 9554, loc. of para type) . CORDULA INFLATA Stephenson, n.sp. Pl. 44, figs. 9, 10 Right valve small, thin, subtrigonal in outline, about as high as long, strongly inflated, inequilateral, protruding notice­ably toward the lower anterior extremity; greatest inflation at about the midheight, a little in front of the midlength; antero­dorsal slope very high and steep, over­hanging, rounded; umbonal ridge sharply rounded to subangular; shell just in front of umbonal rid~e full and plump above, becoming slightly excavated below; pos­terodorsal slope high, steep, sinuous, over­hanging. Left valve very much less inflated than the right, and having a very much lower, non prominent beak. Beak of right valve very prominent, strongly incurved, slightly prosogyrate. situated a little back of the midlength. Hinge and internal fea­tures not obsen·ed. Anterodorsal margin slightly arched; anterior margin sharply rounded below the midheight; ventral margin b r o a d I y rounded, becoming slightly concave near the posterior ex­tremity; posterior margin with a short, squarish truncation, nearly vertical, sub­angular below and above; posterodorsal margin concave. In the available ma­terial the surface appears to be smooth with the exception of very fine growth lines. Dimensions of the holotype: Length 4 mm., height 3.5 mm., convexity about 2.2 mm. This smooth, strikingly inflated species, is unlike any species heretofore described from the Upper Cretaceous of the Atlantic and Gulf Coastal Plain. Types.-Holotype, U.S.N.M. no. 76742; 7 paratypes, right valves, more or less imperfectly preserved, and one imperfect paratype with the two valves attached, all unfigured (U.S.N.M. no. 21018). Distribution in Texas.-Navarro group, Nacatoch sand: Vicinity of Kaufman ( 761, type loc.) ; road 3/ 5 mile west of Kaufman (14098); field 3/5 mile west of Kaufman (14103); 3/5 to 4;5 mile northeast of Chatfield (14117). Unidentified specimens of CORDULA In the Neylandville marl, in a cut of the Texas Midland Railroad, half a mile north of Cooper. Delta County 04062), a calcareous concretion yielded the in­ternal and external molds of the right vah-e of a small, smooth, moderately ventricose, elongated Corbula having a moderately distinct, angular, umbonal ridge, and a squarish posterior truncation sloping a little forward. The material is hardly adequate to serve as a type. ll.S.~.M. no. 76743. In the same formation on the Corsicana road, 21 ~ miles north of Corbet, Navarro County ( 16170), one specimen of a poorly preserved, short, inflated Corbula was found in a concretion with other fossils. U.S.N.M. no. 76744. Poorly preserved Corbulas, apparently different from any of the described species, were found in the N acatoch sand at two localities. Near Kaufman (761, U.S.N.M. no. 21033), the internal mold of a right valve pertains to an elongated, moderately convex species with beaks a little bark of the midlength, and with a compressed, narrow, squarely truncated, protruding posterior extremity (pl. 44, fig. 8) ; there is a suppressed sinuous umbonal ridge, and such of the surface as is preserved indicates a moderate! y strong concentric sculpture. On the Dallas road 3/5 mile west of Kaufman (7545, U.S.N.M. no. 76745), 3 broken left valves indicate an elongated, moderate! y convex, trigonal, coarsely sculptured species, with beaks well in advance of the midlength, with the umbonal ridge strong and subangular, and the posterior end pointed. An exposure of the Kemp clay in the left bank of Colorado River at Webber· ville, Travis County (7601), yielded one left valve of a small, short, smooth, in· Rated Corbula having a sinuous, nonprom· inent umbonal ridge, and a square pos­terior extremity; the specimen might well be the left valve of a species like C. inflata but in the absence of right valves, and on account of its higher stratigraphic posi­tion, its reference to that species is not justified. U.S.N.M. no. 76746. The poorIy preserved internal molds of two undetermined species of Corbu.la were obtained from the Kemp clay in a road ditch 3/S mile west of Elm Creek School, 41/z miles northwest of Lockhart, Caldwell County (16151, U.S.N.M. nos. 76747, 76748). What appears to be the same species as the larger of the two preceding species was obtained in washes in a field east of the Luling-San Marcos highway, 3Vt3 miles north-northwest of Fentress, Caldwell C o u n t y (16149, U.S.N.M. no. 76749). lnvertelwate Fossils of the Navarro Group Family SAXICAVIDAE Genus PANOPE Meaard PA.NOPE SUBPLICATA Shumard Pl. 45, figs. 3-6 1861. Panopaea subplicata Shumard, Boston Soc. NaL Hist. Proc., vol 8, p. 199. lml. Panope subplicata (Shumard). Adkins, Univ. Texas Bull. 2838, p. 171. Shell large, subparallelogrammatic, but variable in outline, inequilateral, equi­valve, rather strongly ventricose, gaping slightly in front, gaping widely behind; the maximum inflation is above the mid­height and extends from below and a little · in front of the beaks backward to the extremity; anterodorsal slopes steep in front of the beaks, flattening out toward the anterior and dorsal margins; a broad, shallow to obscure sulcation extends from the beak obliquely backward and down­ward to the lower end of the posterior truncation. Beaks only moderately prom­inent, strongly incurved, approximate, 1lightly prosogyrate, situated about 2/5 the length of the shell from the anterior eUl'emity. In most of the available ma­terial the anterior part of the shell is a lktle higher than the posterior part. The proportion of length to breadth varies markedly in different individuals, the shell just described probably being proportion­ately longer than the average. One left valve from near Corsicana is 75 mm. long and 45 mm. high. Hinge of right valve with one short, prominent cardinal tooth standing in front of a profound trigonal eocket for the reception of the tooth of the left valve; hinge of left valve with a short, very prominent cardinal tooth, thick below, narrowing to a thin edge above; behind the cardinal tooth is a narrow oblique cleft, and in front of the tooth a deep socket for the reception of the cardinal of the right valve. Nymph short, strong, projecting, bordered by a narrow ligamental groove. Other internal features obscure in the available material. Amero-and posterodorsal margins hor­izontal, forming a continuous, nearly straight line; anterior margin subtrun­cated, slightly convex, the truncation in­clined a little forward, rounding broadly into the dorsal margin above, and rather sharply into the ventral margin below; ventral margin nearly straight, slightly sinuous or irregular; posterior margin truncated, the truncation inclining upward and backward, rounding broadly into the basal margin and rather sharply into the dorsal margin above. The surf ace is covered with coarse, ir­regular growth lines and undulations; in a limited area toward the beak the undula­tions become fairly regular; the undula­tions are coarser where they round down from the main surf ace of the shell to the anterodorsal slope. One of the shells from Chatfield (pl. 45, fig. 3) shows on the well preserved part of the surf ace toward the beak, very faint radiating lines spaced 3 or 4 to the millimeter, each line set with tiny nodes spaced 4 or 5 to the millimeter. These are features not noted by previous authors though similar lines and nodes are present on a specimen from Coon Creek, Tennessee, figured by Wade as P. decisa Conrad, and on Gardner's type of P. monmouthens'is from Brightseat, Mary­land. The same features are beautifully shown on well preserved shells of the . genus from the Owl Creek formation of northern Mississippi; the rows of nodes are traceable out from the beak for a distance of 15 to 20 mm., beyond which the nodes are not arranged in rows, hut become scattered in discriminate Iy and in great numbers over the surface; they be­come more widely spaced toward the margin of the shell. On the types of P. decisa (internal molds) the small nodes, if originally present, are not preserved. Dimensions of an adult shell with both valves attached (pl. 45, figs. 5, 6): Length 99 mm., height 54 mm., thickness about 39 mm. Panope subplicata was described, but not illustrated, by Shumard, and the type material is not known to have been pre­ served. Two imperfect specimens have been found near Chatfield. Navarro County, the type locality of the species, one of which is designated neotype; the other specimen is the internal mold of a left valve with considerable shell material adhering about the umho and along the dorsal margin (pl. 45, fig. 4). The Un-iverst'.ty of Te:i~a.s Publication No. 4101 The type of Panope tfocirn Conrad.:!71 compared with P. suhphcata, has the beaks a little nearer the anterior end, and the posterior truncation is a little steeper. The specimen marked type and the 9 other specimens with it (all internal molds) are labelled as havin~ come from Burling­ton County, New Jersey. Both Whit­field:!':! and Weller:.!•:1 included specimens under P. decisa that probably do not lwlong to that species. Pmwpe elliptica Whitfield from the "Upper marl" of New Jersey, now known to be an Eocene species, lacks the pro­nounced anterior and posterior trunca­tions of P. subplicata and P. decisa. The shell referred to Pano pe decisa by Wade:.!•·l is similar to the Texas species, but it is proportionately shorter and higher, is more inflated below the umbo, and is more constricted posteriorly. Well preserved shells from the Owl Creek for­mation in northern Mississippi are also very close to the Texas species but are proportionately higher and shorter and have more prominent umbos. The same may be said of Panope monnwuthensis Gardner,~•s which in addition is more inflated below the umbos. All of the species cited are more coarsely sculptured concentrically than the Texas shells. Types.-Shumard's type material is probably lost. One of two imperfect speci­mens from near Chatfield is figured and is designated neotype, U.S.N.M. no. 76750; the other specimen is also figured, U.S.N.M. no. 21095. A more complete ~pecimen ( plesiotype) from near Cor­sicana is figured, U.S.N.M. no. 76751. Distribution in T exas.-Navarro group, Nacatoch sand: Vicinity of Chatfield (762, type loc.) ; north edge of Corsicana (518); vicinity of Corsicana (763, 1 ~pecimen figured) ; 2 ~ miles north of Corsicana (14114). !!7 1Conrad. T. A.. Acad. !'lat. Sci. Philadclph:a Jour., 2d ser.. vol. :~. p. 275, pl. 2.i, fi:!. 19, 1853, !!7!!W!Jitfield, H. P .. lf.S. Geo!. Survt•y Mon., vol. 9, p. 181, pl. 21, figs. 5.8, 1885. !!7:1Wellt•r, Stuart, Gt>ol. Survey New Jersey, Paleontology, vol. 4, p. 616. pl. 73, fi:!s. 3·5, 1907. 271Wad(~. Bruce, l-, S. Gcol. Survey Prof. Paper 137, p. 98. pl. 32, fi~s. 8, 9, 1926. !!7'•Gardnl'r, Julia. :\laryland Gcol. Survey, Upper Cretace· ous (2 vol ::<. ), p. 1::2, pl. 15, figs. 1, 5, 1916. Outside distribu,tion.--Arkansas: Naca· lo<'h sand. Family GASTROCHAENIDAE Genus GASTROCHAENA Spengler The O'eneric name Gastrochaena was · r-S I • 1783 mtroduced by Lorentz peng er216 m . He included under this genus three Recent species which he named, described, and fiO'ured (plate opposite his page 182),ii~ order as follows: G. mumia (fig~. 1-7) ; G. czmeifonnis (figs. 8-11); and G. crmbizun (figs. 12-17). Spengler did not desirrnate which of these species should he the ~ype of his new genus. It is evi· dent from his figures that G. mumia is generically distinct from the other two species. In 1789 Bruguiere277 named the genus Fistulana without describing it or desig· natin(J' a type species. Bruguiere died before his :ork was completed and in 1797 part of his uncompleted text, pp. 85-132, and pls. 96 to 286 of the Tableau Encyclo· pedique, were published under one cover; plate 167 gives good figures (figs. 17-22) of the shell and the straight tube of a species of boring mollusk such as has recently been accepted as belonging to the genus Fistulana. In 1798 Cuvier28 undertook to supply j a type for Fistulana by naming Teredo clava Linne as the type species, but un· fortunate! y this species, as determined by the illustrations cited by Linne279 is an en ti rely different shell from that to which the name Fistulana has been generally 270Spcnglcr, Lorentz, Nye Samling nf ontologia Indica. Cretaceous fauna of so:ithnn InJia. vol. 3, p. XY, 18i0. ~JCos!'mann. :\L. Catalogue Illu!:'trc des coquilles fossii<'s ell' I Eoct'ne des en\"irons de P;iris, Prt'm.cr Fascicule, p. 9, 1886. ~"':' 1Fi..rlwr. Paul. :\lanucl de conrhyliologic, pp. 1129-1130, pl. 23. fig. 16. 1887. ~"':•!!Btll' f(t1n~·. E.. Dantzcnbcrg. Ph.. and Dollfus, G., Les mollusqucs marins du Rous~illon. Tome 2, Pelecypodes, p. 602, 1896. :!l\.>W oodring, w. P., Carnl'gic Inst. Washington Pub. 366, p. 191, 1925. !!'.•t\\'oodring, W. P., Carnegie Inst. Washington Pub. 385, p. 22. 1428. !.'!•~·Smith, E. :\., Proc. :\1alac. Soc. London, vol. 6, p. 18.'l. 1905. ~":•;Jr1·dale. T<'m. Prnr. :\lalac. Soc. Lor.don, vol. 11, pp. :.:%-21r;-, 1915. as the type of Ga.strochaena. Stoliczka's designation was overlooked by Iredale and apparently by all authors subsequent to 1870. The shell of Gastrochaena is elongate. rectangular in outline, and the animal secret;s a long, straight, tapering, thin, calcareous tube "''hieh stands upright in the sand of the seabottom into which the ani· mal bores. The tube is characterized on the exterior by rather closely spaced an· nulations; in the size and form of the shell, and in the shape of the tube, the Recent species, Gastrochaena mumia Spengler, is remarkedly like the Upper Cretaceous species, Gastrochaena ripleyana Stephenson, described below, and differs only in details that do not appear to be of more than specific value. Gastrochaena is represented in the Upper Cretaceous of the Atlantic and Gulf Coastal Plain by G. linguiformis Weller from the Merchantville clay marl of New Jersey, and G. ripleya.na Stephenson, from the Ripley formation and its equivalents, of the eastern Gulf region, and from the Nacatoch sand of Texas. The so-called Gastrochaena americana Gabb::!9i from the Vincentown lime sand of New Jersey (Eocene), does not belong to Ga.strochaena; a shell recently uncov· ered in a tube of this species appears to be more like the Recent species which Spengler called G. cuneiformis than it is like the generically distinct G. mumia. The present writer in 1937 made Gabb's species the genotype of the new genus Kumrnelz"a (Jour. Wash. Acad. Sci., vol. 27, no. 2, pp. 58-64, text figs. 1-8). Fistulana ocalana Dall,298 from the Ocala limestone of Florida, which is based on an incomplete mold of the tube, may be a Gastrochaena. GASTROCHAENA RIPLEYANA Stephenson, n.1p. Pl. 46, figs. 5-14 1926. Gastrochaena americana Gabb. Wade, U.S. Geol. Survey Prof. Paper 137, p. 99, pl 32, figs. 5-7. Shell thin, elongate, subrectangular, equiYalve, extremely inequilateral, strongly 297Gabb, Wm. M., Acad. Nat. Sci. Philadelphia Jour., 24 ser., vol. 4, p. 393, pl. 68, fig. 20, 1860. 298Dall, Wm. H., Wagner Free Inst. Sci. Trans., vol. S, pt. 4, p. 826, pl. 35, fig. 23. 1898. Invertebrate Fossils of the Navarro Group ventricose in front, gradually tapering wedge-like to a thin edge behind; the front end of the shell is squarely truncated almoet at right angles to the longitudinal dimension; ventrally the shell is widely gaping, the opening having approximately the form of an elongated isosceles triangle, the length of the gape in the holotype being 25 mm., and the maximum width in front about 11 mm.; from the edge of the anterior truncation the main surf ace slopes gradually backward in a broad curve to the posterior extremity and rounds over more abruptly to the dorsal margin. Beaks small, nonprominent, slightly pro­eogyrate, slightly separated, situated at the anterior extremity. Hinge edentulous. Ligament long, thin, external, opisthodetic. Anterior adductor scar, as seen in a frag­ment of shell broken from the holotype and subsequently glued back in place, elongated, lying close to and parallel to the vertical anterior margin; below its lower end is another small, circular muscle ecar. Pallial sinus obscure in the avail· able material. The anterior margin is 1quarely truncated almost vertically, the two edges curving out a little as they ~t, forming a low sharp keel; the ven­tral margin is long, descending posteriorly, nearly straight, slightly concave just back of the truncated front; posterior margin aubtruncated nearly vertically; postero· dorsal margin long, very broadly arched, descending posterior 1y. The surf ace is marked by concentric f'Owth lines and ridges which vary greatly m strength on different parts of the shell; the truncated front is covered with coarse, aharp-crested ridges which descend from the upper angle of truncation downward and inward, bending up sharply and tend· ing to fade out as they approach the inner, closed margin; on the main surf ace a shallow sulcus extends from the beak obliquely backward and downward to the ventral margin; in front of this sulcus the growth lines are irregular, strong, and lharJ>; back of the sulcus the surface is nearly smooth from the front backward to about the midlength, back of which the growth lines become sharper and more irregularly developed. On the smooth part of the surface back of and above the aulcus the magnifying glass reveals exceed­ingly fine, closely packed, radiating rows of tiny nodes or tubercles; at a distance of about 10 mm. from the beaks these rows of microscopic nodes break up into fine, ir­regular surface stippling which character­izes the surf ace to the posterior extremity even among the more coarsely developed growth lines. This mollusk secrets an outer long, straight, thin, tapering tube of calcium carbonate, having a maximum measured diameter of about 18 millimeters, and an estimated maximum length of 150 milli­meters or more. The tube is marked by closely spaced, regular transverse annula­tions; fine, irregular, longitudinal stria­tions may be seen toward the smaller end of some of the tubes, suggesting mechani­cal scratching caused by the forcing of the tube upward through the sand as the animal sought to prevent the small end of the tube from becoming covered and sealed by the sediments being deposited on the sea bottom above it. The small end of the tube, as seen in one specimen, is noticeably constricted in bottle-neck fashion. Dimensions of the holotype, a well pre­served shell with valves attached: Length 29.2 mm., height at front end 6 mm., thickness 11.6 mm. This species is based on several well preserved shells and internal molds and on numerous tubes from the Owl Creek formation, on Owl Creek, Tippah County, Mississippi. The Texas material includes two fairly good imprints of shells in fragments of internal molds of tubes ( 13568) , one poor imprint of a shell in a fragment of an internal mold of a tube ( 12927) , and one well preserved internal mold of the large end of a tube representing near1y half the original length (761). This material is hardly adequate for satisfactory identi­fication, but allowing some individual variation, the imprints of the shells agree fairly well with the typical Owl Creek shells; the imprints suggest a shell with a squarer posterior truncation, and having a more deeply impressed sulcus extending from the beak to the posteroventral mar­gin, but until more and better specimens afford more conclusive grounds for separa­tion, these shells and tubes may be re­garded as belonging to Gastrochaena ripleyana. The University of Texas Publication No. 4101 Castrochaena whitficldi \Veller,~nn from the Navesink marl (Upper Creta­ceous) ~f N~w Jersey, as shown hy the figured 1mpnnt of the holotype, is less square~y t~·uncated in front, has a deeper concavity m the anteroventral maro-in and is much higher posteriorly than fhe' Owl Creek species; it appears to have con­structed a very similar tube. Gastrochaena linguifonnis \Veller,3oo from the Merchantville clay marl of New !ersey, is based on a poorly preserved 1mprmt of part of a shell in a tube which is hardly. adequate to serve as a typ~; com­pared with other described species it ap­pears to be specifically distinct havinrr a . h h ' b strmg ter s ell with dorsal and ventral margins subparallel. Types.-Holotype, U.S.N.M. no. 76752; 4 figured paratypes, U.S.N .M. no. 76753; 1 unfigured paratype, U.S.N.M. no. 76754. From the Owl Creek formation 2~2 miles no.rt~ea.st . of Ripley, Tippah County, Mississippi. Examples from Texas, U.S. N.M. nos. 20967, 76755. Distribution in Texas.-Navarro group, Nacatoch sand: A tube from the vicinity of Kaufman (761, figured) . Navarro group, Corsicana marl: Castro­ville road, 1 1/ 5 miles west of Leon Creek Bexar County (15522) ; 6 miles east of Castroville ( 16156) ; well 7 / 20 mile south by west of St. Mary's University, Bexar County (16353) ; 2 miles east of Marion (Tex. Bu. 2395) ; 1 4/ 5 miles N. 20° w: of Tona siding (15545) ; 4 miles south­west of Quinlan (17385) ; 7 miles south 3 miles east of Greenville (11250) · 3 7 /10 miles southwest of Campbell .( l5547) · about 3 miles south-southwest of Campbell (] 2927) ; 11/1: miles south by east of Oak Grove (13568, 1 figured specimen; 16160). Outside distribution.-Mississippi: Owl Creek formation and Prairie Bluff chalk. Tennessee: Fragments of tubes reported by Bruce Wade from the Coon Creek tongue of Ripley formation. \Vest-central Alabama: Questionably in the Prairie Bluff chalk. Range.-Tubes of Gastrochaena, some of them containing the imprints of the slwlls. occur in Texas at several localities in beds of Taylor age, including the Wolfe !!!l!l\\"e Jl .. r. Stuart. G1·01. Survey ~ew Jcr.;ey, Paleontology, 'ol. -l, p. 618, pl. 73, figs. lO-i2, 1907. 30 miles northeast of Quinlan (l (> 162, fig­ured) ; road, 2 miles southwest of Kauf­man (7546). Navarro group, Kemp clay: Webber­ville (13910); near Webberville (7602). Outside distribution. -Chattahoochee region (Alabama-Georgia) : Blufftown formation and Ripley formation (upper part). North Carolina: Questionably in the Snow Hill member of the Black Creek formation. New Jersey: Woodbury clay. Range.-Ranges from the Exogyra ponderosa zone, upward through the Exogyra costata zone, in the Atlantic and Gulf Coastal Plain. CADULUS COONENSIS Stephenson, n.sp. Pl. 46, fig. 23 1926. Cadulus obnutus (Conrad). Wade, U.S. Geol. Survey Prof. Paper 137, p. IOI, pl. 33, figs. 7, 8. Wade refers this species to Cadulus obnutus (Conrad), but says: "The Tennessee specimens referred to this species are a little more inflated mediallv than the New Jersey specimens." H{s figured specimen is in fact strikingly in­flated in comparison with C. obnutus, and fully warrants recognition as a separate species. The following description is based on Wade's figured specimen which is here designated the holotype; it is a nearly complete shell. Shell small, smooth, curved, strongly inflated; the equator appears to be a trifle in advance of the midlength, from which the tube tapers regularly toward the aperture; in the other direction the tube is noticeablv constricted about halfway between th~ equator and the apex. The outer side of the curved tube is regularly convex from the equator to the aperture but in the other direction the curve becomes broadlv concave as it approaches the apex; th~ regularity of the curve of the inner side of the tube is interrupted by a broad swell which centers slightly in advance of the midlength. The tube is slightly flat­tened centrally at right angles to the plane of curvature, making a broadly ovate cross section. Twelve paratypes in a collection made in 1933 by H. D. Miser and G. A. Cooper show a noticeable variation in form, but all have the strong central inflation which characterizes the species. The apical orifice is circular and the aperture is broadly ovate. Approximate dimensions: Length 3.2 mm.; greatest diameter 1.1 mm.; maxi· mum diameter of aperture 0.6 mm.; dia· meter of apical orifice 0.25 mm. The Texas specimens referred to this species are all slightly smaller than the holotype, but they have essentially the same inflated, slightly flattened form. T1ypes.-Holotype, U.S.N.M. no. 32824; 12 paratypes, U.S.N.M. no. 76784; from the Coon Creek tongue of the Ripley formation at Coon Creek, McNairy County, Tennessee. One figured example from Texas, U.S.N.M. no. 76785. Distribution in Texas.-Navarro group, N acatoch sand: Road, 2 miles southwest of Kaufman (7546) ; Watkins' place 3 miles north of Corsicana (9552, figured); road 5 miles south-southwest· of Corsicana (7573). Outside distribution.-Tennessee: Coon Creek tongue of Ripley formation. Class GASTROPODA Subclass STREPTONEURA Order ASPIDOBRAHCHIA Suborder DOCOGLOSSA Family ACMAEIDAE Genus ACMAEA Eschscholtz ACMAEA? OCCIDENTALIS (Hall and Meek) 1 Pl. 47, fig. 1 ?1852. Orbicula Owen, Rept. U.S.Geol. Survey Iowa, Wisconsin, and Minnesota, pl. 7, fig. 11. 1856. Capulus occidentalis Hall and Meek, Am. Acad. Arts and Sci. Mem., Boston, n. ser., vol. 5, p. 385, pl. 1, figs. 13a-d. 1860. Tectura occidentalis (Hall and Meek). Meek and Hayden, Acad. Nat. Sci. Phila· delphia Proc., vol. 12, p. 423. 1876. Acmaea occidentalis (Hall and Meek). Meek, Rept. U.S.Geol. Survey Terr., vol. 9, p. 295, pl. 18, figs. 3a, b. Shell thin, depressed, suhconical, sub· circular in outline, apex about one-fourth the length of the shell in advance of the Invertebrate Fossils of the Navarro Group middle. The surface is smooth with the exception of fine growth lines and descends in nearly straight slopes from the apex to the margins; there is, how­ ever a slight humping a little back of the 'apex, and, because of the. acentric position of the apex, the anterior slope is steeper than the posterior. The internal features are not preserved. Dimensions of the shell shown in plate 47, figure 1: Length front to rear 16 mm., width 16 mm., height about 4 mm. There are no apparent differences on which these Texas shells can be separated from A. occidentalis (Hall and Meek), and they are provisionally referred to that species. The species from Coon Creek, Tennessee, described by Vlade814 under the name Anisomyon wieseri may belong to A.cmaea, but compared with A. oc~i­ denta./,u it is more ovate in outline, and its apex is less acentric. Types.-The type material of t?is species was collected by F. B. Meek ~nor to 1856, in the upper part of the Pierre shale on Sage Creek, in T.l or 2 S., R.~4 E., about 40 miles east by south of Rapid City, South Dakota. The present where­abouts of the material is unknown. The specimen figured by Meek in 1876, cited in the synonymy, was also collected in the upper part of the Pierre shale, . on Cheyenne River, near the Black Hills, South Dakota. Plesiotype from Texas, U.S.N.M. no. 76786. Distribution in Texas.-Navarro group, Neylandville marl: 2~ miles north of Corbet (17365) . Navarro group, Corsicana marl: 1 3/10 miles north of McQueeney (15524). Navarro group, Kemp clay: West of Zuehl (7720; 7721, includes 1 plesio­type); near Deatsville (764, 14125).; branch, 6% miles southwest of Currie (J.4139); Brazos River, 2 miles above Milam County line (13776). Oauide distribution.-Western Interior: Pierre shale. Range.-The known range in Texas is through the Navarro group. The type ""Wade, Bruce, U. S. Geol. Survey Prof. Paper 137, p. 180, pl. 60, fis. io, 1926. came from the upper Pierre beds of South Dakota. Suborder RHIPIDOGLOSSA Family EUOMPHALIDAE Genus WEEKSIA Stephenson, n••en. T y p e s p e c i e s.-Pseudomalaxis amplificataWade.s11> Etymology.-ln honor of Mr. Dave Weeks, owner of the classic Coon Creek fossil locality discovered by Bruce Wade in McNairy Co., Tennessee. Shell moderately large, discoidal. Spire involute, immersed. Whorls 4 in adults, subrectangular in cross section, and in· creasing markedly in size to a much ex­panded body whorl. Protoconch dextral, small, smooth naticoid in form, elevated above the plane of the involution, coiled about twice. Anterior and posterior angulations somewhat irregularly and not closely nodose. The inner shoulders of the whorls round down to the rather open suture. This genus differs from Pseudomalaxis Fischer, which was based on a Pliocene , species from Sicily, in !hat th~ nuc!eus is elevated instead of bemg coiled m the plane of the volutions, the whorls expand much more rapidly, and the nodes on the anterior and posterior angulations, in­stead of forming closely and regularly spaced crenulations, are widely spaced and · irregular; the genus also lacks nodes on the inner shoulders of the whorls next to the suture. The two specimens from Coon Creek, Tennessee, which Wade described under the name Pseudomalaxis ripleyana, hear a closer resemblance to Pseudomalaxis, both in form and in the character of their protoconchs, than does Weeksia am pli­ficata (Wade), and may belong to that genus, but the two specimens hel.ong to two very distinct species; he designated the specimen shown in his plate 59, figs. 5-7, as the holotype of P. ripleyana; the other specimen, shown in figures 8 and 12 of the same plate, is in need of a new specific name. ll&Wade, Bruce, U.S. Geo1. Survey Pr of. Paper 137, p. 175, pl. 59, 6g11. l~. 1926. 258 The Unfr,ersity of Te:ras Publicatfon No. 4101 Delphi1111la lapidosa Morton and .Straparolus subplanus Cahh, hoth of \vhich wrre de~crihcd from spe('ifically indeterminate internal molds, probahly belong to this genus. WEEKSIA LUBBOCKI Stephenson, n.sp. Pl. 47, figs. 2---1 Shell of moderate size and thickness, discoidal. Spire involute and consider­ahly sunken, making the top of the shell ('OlH'avc. Umbilicus wide and shallow, hut deeper than the spiral concavity. Whorls three, increasing rapidly in size, subrectangular in cross section. wider in the horizontal than in the vertical direc­tion~ whorls flattish on top, base and side. Although compactly coiled, the body whorl of the type shows a slight tendency to become more loosely attached to the penultimate whorl just -back of the aper­ture. Protoconch roughened by surface crystallization in the holotype, but ap­µarently a small, smooth, dextral nau­ticoid shell, coiled 2% or 3 times, elevated above the flat-topped surface of the nearest whorl of the spire. The sur­face is nearly smooth except on the posterior and anterior angulations, which bear widely spaced, moderately prominent nodes. the spacing of which increases an­l<:'riorly to a maximum of about 6.5 mm. on the holotype; the nodes on the two angulations stand opposite each other. The fine incremental lines on the top and hasc of the whorls extend forward and inward from the angulations with a strong obliquity, curving more strongly inward as they approach the sutures; between the angulations these lines cun-e broadly bachvard. The body whorl is broken away for several millimeters back of the aperture. Dimensions of the holotype: Height of the body whorl, which is the maximum height of the shell, 5 mm.; greatest dia­meter 14 mm. This species is clo~elr related to W eeksia am plificata CWade) , from Coon Creek. Tenne~see. but it differs markedly in the wide ~pacing of the nodes on the rosterior and anterior angulations. Holotype.--V.S.N.M. no. 20908. Named for the Hon. Francis R. Lubbock, Gov. t'rnor of Texas, 1861-1863. /Jistrihution in Texas.-Navarro group, Nacatoeh sand: Vicinity of Corsicana {/()3, type loc.) ; road 2 miles. southwest of Kaufman (7546); field 2 miles south· west of Kaufman (7547); vicinity of Kaufman (761). Genus PSEUDOMALAXIS Fischer PSEUDOMALAXIS? PATENS Stephenson, n.ap. PJ. 4 7, figs. 5-7 Shell of medium size, broadly dome· shaped. Spire flattish near the apex, rounding off broadly from the apex across the tops of the whorls to the posterior anrrulation. Whorls 6 in the holotype, t"I • • • suhsquarish jn cross sect10n, mcreasmg very rrradually in size, closely appressed.Proto~onch smooth, flat, dextral, coiled about twice. The posterior and anterior angulations are sharp and are finely crenulated. The upper surface of the whorls between the suture and the pos· terior angulation is very broadly rounded, with, however, a very broad shallow sulcus just back of the posterior angula· tion; the side between the posterior and anterior angulations is also very broadly rounded and inclines strongly inward; the surface of the whorls within the umbilicus is broadly rounded except for a shallow sulcus which lies just within the anterior angulation of the body whorl, and follows the suture to the apex within the umbilicus. The umbilicus is wide open and bowl-shaped. The surface is 11early smooth with the exception of the crenulations on the angulations and rather coarse growth lines; in a good light, however, one can detect a few very faint, fine spiral lines on the top of the whorls and on the outer side of the body whorl. The growth lines on the top of each whorl are directed strongly backward from the suture to the posterior angulation; be· tween the angulations they bend broadly backward; and within the umbilicus they trend forward. The aperture is broken on the holotype, but is subsquarish. Dimensions of the holotype: Height 4.5 mm., diameter 12 mm. Invertebrate Fossils of the Navarro Group In the simple, flattish protoconch, in the crenulations on the posterior and an­terior angulations, and in the squarish cross section of the whorls this species agrees closely with the juvenile shell from Coon Creek, Tennessee, incorrectly figured by Wade316 as an example of Pseudomal­axis ripleyana. On account of the extreme youth and different state of preservation of the Tennessee shell it is not possible to establish its specific identity with the Texas species, but the two are certainly congenenc. P. pat ens appears to agree in most of its essential characters, including that of the p r o t o c o n c h , with P. zanclaea (Philippi), the type species of the genus, from the Pliocene of Sicily. The great difference in age, however, suggests the advisability of caution in referring it to that genus. Holotype.-U.S.N.M. no. 76787; 1 un­figured paratype, U.S.N.M. no. 76788. Distribution in Texas.-Navarro group, Nacatoch sand: Vicinity of Corsicana (763, holotype) ; 21h miles west hy south of Corsicana (17368, paratype) . PSEUDOMALAXIS? sp. Two imperfectly preserved specimens representing this genus, found in the up­per part of the Kemp clay in a draw a mile west of the Austin road 6 miles north of Lockhart, Caldwell County (13777), are similar in form to P. patens, but ex­hibit fine rather sharply developed spiral sculpture and are doubtless specifically distinct. U.S.N.M. no. 76789. Genus HIPPOCAMPOIDES Wade HIPPOCAMPOIDES sp. PI. 47, figs. 24, 25 An internal mold with the sculpture faintly impressed upon it, from the Cor­sicana marl at a bluff on the left bank of San Marcos River, half a mile below Martindale, Caldwell County ( 15526) , appears to belong to the genus Hip­pocampoides Wade. The shell is of mod­erate size, only gently convex apically and gently convex on the side of the largest whorl; the whorls increase rapidly in size 118Wade, Bruce, U. S. Geol. Survey Prof. Paper 137, pl. 59, figs. 8 and 12 (not figs. 5-7), 1926. and the height of the shell increases rap­idly toward the aperture; the peripheral margin is angulated and the cross section of the outer whorl is quadrilateral; umbilicus apparently wide and deep, its outer margin greatly produced; in the mold a sharp thin sulcus separates the produced margin from the main shell; evidences of 7 or 8 revolving ridges on the side, and 7 or 8 on the top, of the largest whorl are afforded by faint depres­sions with rows of pits in their bottoms; at least three coils can be differentiated. Dimensions of the figured specimen: Height about 18 mm., greatest diameter about 21.5 mm. U.S.N.M. no. 76790. Family DELPHINULIDAE Genus CALLIOMPHALUS Cossmann Type species.-Turbo squamulosus Lamarck. If the recommendation of the Interna­tional Commission, that a name is not to be rejected because it differs from a name aheady in use only in termination or in a slight variation in spelling, then the name Calliomphalus Cossmann ( 1888) should not be replaced by Callomphalifer Cossmann,317 because of the previous use of Callumphala Adams and Angas (1864). CALLIOMPHALUS BELLULUS Stephenson, n.sp. Pl. 47, figs. 8, 9 Shell small, trochoid, umbilicate. Apical angle about 90 degrees, but anteriorly the spiral angle decreases to 65 or 70 degrees. Whorls 4 or 5, plump on the sides, nearly circular in cross section. Suture deeply impressed. The protoconch is not well preserved but is flattish. The growth lines have a strong forward obliquity in their trend from below upward. The periphery rounds down regular!y to a subflattish base. The shell is characterized by tuberculated, spiral lirae; on the body whorl between the suture above and the border of the base below there are nine primary spirals, and in each of the lower four interspaces is a much smaller secondary spiral which is also finely tuberculated and which fades out as it passes backward toward the penul­timate whorl; on the base are 10 rather 3liCossmann, M. , E.ssais Palcoconch. Comp., Liv. 11, p. 91, 1918. The Unitersity of Texas Publication No. 4101 closely crowded, low spiral lirae of some­what irn~~rnlar stren!!th and la•arinrr more L \ r""' or less obscurely dewloprd tuherclc-s which are aligned from lira to lira in the direc­tion of the rather co~Hst"' growth lines. In general the tubercles are most prominent on the> upper or posterior part of the body whorl and tend to es. \Yhorls 5, nearly Hat on the sides. Suture narrow, deeply impressed. increasing in depth and width toward the aperture. Protoconch badly 'rnrn. but apparently small and flattish. Growth lines inclined strongly forward from below upward. Periphery subangu­lar. Base broadly and regularly rounded. Surface of body whorl aboYe the periphery ornamented with 5 unequal, finely tuber­culated spiral ribs: the lowest rib at the peripheral angle is more than twice as lar~e as the others; the uppermost rib just 3 '"Wddr. Rrucc. l". S. Geol. Suney Prof. Paper 137, p. 178. rl. 60. fig!-. I-3, 19::!6. below the suture is a little stronger than the ones below it. and presents a row of heads ohliquely elongated parallel to the rrrowth linPs ~ tlw 3 intermediate spirals are ~ather weak ans; about 10 primaries are exposed on the penultimate whorl. The aperture is broadly subovate, and the parietal wall is covered with a thin film of callus. Dimensions of the incomplete holo­ type: Height 23 + mm., diameter 11 mm. Holotype.-U.S.N.M. no. 76922. Distribution in Texas.-Navarro group, N acatoch sand: 3 miles northeast of Corsi­cana (9545). BELLISCALA FORSHEY! (Shumard) Pl. 49, figs. 13, 14 1861. Sea/aria /orsheyi Shumard, Boston Soc. Nat. Hist. Proc., vol. 8, p. 195. Shell of moderate size, turreted, spiral angle about 40 degrees. Whorls plumply rounded, compactly coiled; 5 whorls pre· served on the larger of the two available specimens, on which part of the body whorl and several apical whorls are miss­ing. Suture deeply impressed, bordered below on the posterior part of the whorl by a rather weakly developed narrow fasciole. The axial ribs are narrow, mod­erately prominent, have a slight backward obliquity in trend from above downward and number 23 on the largest whorl pre­served; the ribs become weak where they cross the posterior fasciole and fade out on the base before reaching the columella; between the ribs are numerous fine, fili­form, axial lines. The body whorl rounds down steeply on the base to the columella. The surface is further ornamented with a system of small, distinct spiral ribs which are well developed both between and on the crests of the axial ribs; on the smaller whorls of the spire there are about 7 pri· mary ribs and an equal number of inter­mediate secondary ribs; as the whorls in· crease in size still smaller tertiary ribs appear between the primary and secondary ribs, and this feature is especially marked on the penultimate whorl and on the base of the body whorl; the spiral ribs are well deYeloped on the base to the border of the columella. The aperture and a consid· erable part of the body whorl are broken Invertebrate Fossils of the Nava.rro Group away; apparently the aperture is broadly subovate in outline with its long axis slightly oblique to the vertical axis of the shell. Dimensions of the figured spicimen: Height 19 + mm., diameter 11 mm. Esti­mated total height 24 mm. Types.-The holotype is lost, and no other specimens have been found at Chat­field, the type locality. The incomplete specimen figured and an accompanying fragment are from near Corsicana, U.S.N. M. nos. 20892, 20892a. Distribution in Texas.-Navarro group, Nacatoch sand: North edge of Corsicana (518). BELLISCALA CRIDER! Stephenson, n.sp. Pl. 49, figs. 15-18 This species is based on one incomplete specimen which includes part of the body whorl and most of the penultimate whorl, found with B. forsheyi (Shumard), near Corsicana. The shell is much like Shu­mard's species, but is more slender, having a spiral angle of about 30 degrees; the whorls are not quite so plump, the pos­terior fasciole is a little weaker, and the axial ribs are more prominent across it; there is a weakly developed peripheral angle, below which on the base the axial ribs become weak and fade out before reaching the columella. The spiral sculp­ture includes small primary ribs with still smaller intermediate secondary, tertiary and quaternary ribs, which produce a finer, more compactly crowded sculpture than that on B. forsheyi; the base is also marked with fine closely crowded threads of nearly uniform size. Holotype.-V.S.N.M. no. 76815. Named in honor of Mr. A. F. Crider, Geologist, Shreveport, Louisiana. Distribution in Texas.-Navarro group, Nacatoch sand: North edge of Corsicana (518). Family MATHILDIIDAE Genus TUBA Lea The Texas species, Tuba? manzaneti, is similar in form to the genotype, Tuba a/,ternata Lea (Eocene) , but has a some­what higher spire and lacks an umbilical perforation, which, however, in Lea's species is small and narrow. TUBA? MANZANETI Stephenson, n.sp. Pl. 48, figs. 15-17 Shell of medium size, thick and strong, turbinate, with spiral angle of about 48 degrees. Two and part of a third whorl preserved in the holotype, with part of the body whorl and 3 or 4 apical whorls missing; whorls plumply rounded, com­pactly coiled. Suture deeply impressed. Surface sculpture ornate. On the penulti­mate whorl are 10 spiral ribs of W1equal size arranged in order from rear to front as follows: The second rib is larger than the first, the third is larger than the second, and the three cover a band about a milli­meter wide; the fourth to the tenth ribs, starting with a small one, alternate mark­edly in prominence and width; three of the larger of these ribs are each about half a millimeter wide, and constitute the major ones of the series; the tenth rib is larger than the other intermediate ribs; forward from the tenth rib on the base of the body whorl the ribs continue to alternate in size to the fifteenth rib, between which and the columella are 15 small, closely packed, subequal ribs. The spiral ribs are crossed by axial rows of narrow, sharply defined, closely spaced beads, giving to the shell under a magnifying glass a handsomely cancellated appearance. There is no peri­pheral angle, the body whorl rounding down plumply and steeply to the colu­mella. About a third of the body whorl is broken away, but the aperture is probably broadly subovate to subcircular; a thin callus partly preserved indicates a thin inner lip. Umbilical fissure narrow, dis­tinct. Dimensions of the holotype: Height 14 + mm., diameter 12 + mm. Total estimated height 20 mm. This species is closely related to T. parabella Wade, from Coon Creek, Tennes­see, but the spiral angle is greater, the axial beads are more closely crowded on the spiral ribs, and the major ribs on the periphery of the whorls are not quite so prominent, giving to the whorls a more smoothly rounded appearance. It is unfortunate that the type of Tuba bella Conrad from the Ripley formation at Eufaula, Alabama, has been lost, for it is obviously closely related to both T.? manzaneti and T. parabella. The University oj Te.i~as Publication No. 4101 Tuba? reticu lata Jolmson,:i~n from the Cretaceous in a well near Mount Laurel, 1'ew Jersey. is p:enerically and specifically distinct from both the Texas and Tennesse~ species of Tuba; it is probably an U rceo­labru m. Holotype.-r.S.N.M. no. 21079. Named for Padre Manzaiwt. one of the founders of the l\'1 ission San Francisco de los Tejas, near Neches River. in 1690. . Distribution in Texas.-Navarro group, Aacatoch sand: Vicinity of Chatfield ( 762, type loc.) ~ vicinity of Corsicana (763) ; vicinity of Kaufman (761) . TUBA? sp. An imperfectly preserved fragment of the bodv whorl of a Tuba? from the Nev­landvill~ marl in a roadside ditch 21h miles south of Ben Hur, Limestone County (15543), exhibits sculpture very much like that of T.? manzaneti except that there is a. marked alternation in size of the spiral nbs all the way up the side of the whorl to the suture. A peripheral angle is scarcely developed and the spiral ribs be­come smaller on the base toward the columella. The geologic age of this species is approximately the same as that of Wade's species, T. parabella from Coon Creek, Tennessee, but the axial beads are th~cker and more closely cro\vded, and in this respect are more like T.? manzaneti. U.S.N.M. no. 76816. TUBA? sp. Pl. 48, fig. 18 A poorly preserved specimen, appar­ently a Tuba, associated with manv individ· uals of Micrabacia navarroensis \\tells, was found by Julia Gardner, in the upper part of the Kemp clay member of the Navarro formation, in a draw half a mile west of the Austin road, 6 miles north of Lockhart, Caldwell Count\ (13777). The shell is small and slender for the genus. Four plus whorls including the body whorl are preserved, and 5 or 6 apical whorls are m1ssmg. The sides of the whorls are m()deratel y C"Onvex. and the suture is deep.ly impr:ssed. There is a barely per­ceptible peripheral angle below which the base declines steeply to the columella. :l~~John!lon . C. '\'\·...\ca .I. :'\at. Sci. Philadt·lphia Proc., vol. 50. p. 461 , 1898. The surface is covered with evenly noded rcvoh-ing ribs of somewhat variable size, numbering 5 or 6 on the penultimate whorl: the width of the interspaces is pqual to or less than that of the ribs. The ribs on the lower part of the whorl and in the vicinity of the peripheral angle ap· pear to be larger than elsewhere, and on the base toward the columella the ribs become considerably smaller. Aperture not well preserved, but apparently circular . The shell is estimated to have a length of about 16 mm. and a diameter of 5 mm. The apical angle is probably about 30 degrees. The shell is smaller and more slender than T.? manzaneti and lacks the alternation in the size of the spiral ribs on the outer, more convex part of the whorls of that species. U.S.N.M. no. 76817. Genus MATHILDA Semper MATHILDA CEDARENSIS Stephenson, n.sp. Pl. 48, fig. IO Shell small, turreted, slender, spiral angle about 19 degrees. Five whorls pres· ent as preserved, with whorls missing at both ends. The spiral ornamentation above the periphery consists of 2 prom· inent primary ribs, the lower one of which is bifid on the crest, and a small secondary rib in the bottom of the wide interspace; the lower bifid rib is situated at the pe· riphery; the upper rib is a little below the suture; the flattish base is not perfectly preserved, but 2 secondary spiraJs may be seen on the side nearest the periphery. The axial sculpture consists of numerous, fine, sharp, closely spaced ribs which run nearly vertically across the whorls; these are present both on the crests of the spirals and in the interspaces, but are sharpest in the interspaces as preserved. The base, though not well preserved, appears to be nearly flat, descending abruptly from the periphery to the center. Aperture sub· quadrangular. Dimensions: Height 5 + mm., diameter at large end 2.3 mm. The character of the sculpture relates this species closely to Mathilda ripleyana Wade, but the Texas specimen is more slender, and has fewer revolving ribs at the same stage. The axial sculpture on the two species is closely similar. Invertebrate Fossils of the Navarro Group Holotype.-U.S.N.M. no. 76818. Di&tribution in Tems.-Navarro group, Neylandville marl: 2% miles north of Corbet (16170). Family ARCHITECTONICIDAE Genus ARCHITECTONICA Bolten ARCHITECTONICA VORAGIFORMIS Stephea..on, n.ap. Pl. 48, figs. 12-14 Shell of medium size and thickness, de­pressed conical, umbilicate; spiral angle about 95 degrees. Whorls 5 or 6, flattish on the side, with a spiral sulcus toward the lower edge. Suture closely appressed, sharply but not deeply impressed. Proto­conch not preserved. Base flattish with, however, a broad, shallow, spiral sulcus near the periphery; this sulcus is opposite to the sulcus near the lower border of the outer side of the whorl and the two con­strictions together produce a thin, project­ing, flange-like carina on the periphery of the body whorl. Umbilicus wide and deep. Starting from the rim of the umbilicus the growth lines cross the base trending ob­liquely forward, and curving broadly forward as they cross the peripheral sulcus and flange; on the lateral surface of the whorl the growth lines continue upward and somewhat obliquely forward to the suture. The lateral surface of the body whorl near the aperture is ornamented with 7 primary, headed, spiral lirae, the last two ~f which are on the peripheral flange; m each of the interspaces except between the fourth and fifth (counting from the suture downward) is a small, obscure} y ~ded secondary; the seven primary spuals are traceable backward on the whorls toward the apex to the place where the surface is too badly corroded to count them; the secondaries fade out posteriorly, the last trace . of. them disappearing at about the begmnmg of the penultimate whorl. The base is covered with about 15 closely crowded, beaded spiral lirae which are coarsest near the rim of the umbilicus but. become regularly smaller toward th~ eenphery, fa~ing out on the peripheral ~· The rim of the umbilicus is rela­th'ely coarsely nodose, the nodes being e~ongated in the direction of the growth lines. The wall of the umbilicus appears to he covere.:l with spiral lirae which are not clearly uncovered. The li:ps ar~ broken hut the aperture is suhsquansh with a slight obliquity in the direction of the peripheral flange. Dimensions of the holotype: Height 8.8 mm., diameter 14.4 mm. Holotype.-V.S.N.M. no. 76819. Distrib'!'tion in Texas.-Navarro group, Neylandville marl: 2% miles north of Corbet (16170). Unidentified specimens of ARCHITECTONICA Imperfectly preserved specimens which may belong t.o Architectonica, but which are hardly well enough preserved for either generic or specific identification, have been found in the Navarro group at several localities as follows: At Crystal Lake, an artificial lake 5 miles south of Annona, Red River C.ounty (13093, U.S.N.M. no. 76820), an expo­sure of glauconitic sand belonging to the N acatoch sand, at the outlet of the lake yielded the internal mold of a mediu~ sized gastropod having the form of A rchi­tectonica. The whorl is somewhat flattened a~d the periphery is angulated; the under­side of the body whorl is broadly rounded a?d th.e umbilicus . is wide open. The dimensions are: Height 7 mm., diameter 14mm. An imperfect specimen which 1 may be the same species was found in a field on the Simpson place about 2 miles southwest of Katif man, Kaufman County (7547, U.S.N.M. no. 76821). From the Corsicana marl on San Marcos River, half a mile below Martindale, Cald­well County (7621, U.S.N.M. no. 76822) a medium sized specimen mechanicall~ flattened in the marl exhibits some of the shell characters. The surface is covered with fine spiral threads; the under surface of the apical whorls within the umbilicus a!e cov~red with fine, closely spaced axial ribs which appear to he fading out on the posterior part of the body whorl, hut are not uncovered on the middle and anterior parts of the whorl. The diameter of the shell is about 13 mm. A smaller specimen preserved in the same way, and similarly !mt not quite so plainly marked, was found m the marl on the Mexia road, 2% miles east of Cooledge, Limestone County (13832, U.S.N.M. no. 76823), and a speci­men of the same kind came from the marl The University of Texa.s Publication No. 4101 in a branch below public road, 211~ miles north of Tona siding, 5 miles southwest of Quinlan, in Hunt County (155·16, U.S.N.M. no. 76824.) . The bluff on Onion Creek, 21/:.! miles west of old Garfield, Travis County (14156), yielded a small, flattenf' J.89'l. Xenoplwra conchyliophora (Bom) . Dall, Wagner Free lnsL Sci. Trans., vo.1 3, pt. 2, p. 360. (In parL) 1~. Xenophora leprosa (Morton). Johnson, Acad. NaL Sci. Philadelphia Proc., vol. 57, p. 21. 1907. Xenophora leprosa (Morton). Weller, Geol. Survey New Jersey, Paleontology, vol. 4, p. 690, pl. 78, figs. 1-3. 1916. Xenoplwra leprosa (Morton). Gardner, Maryland Geol. Survey, Upper Creta­ceous (2 vols.) , p. 495. 1926. Xenoplwra leprosa (Morton). Wade, U.S. Geol. Survey Prof. Paper 137, p. 162, pl. 56, figs. 7, 8. This species is represented in the Upper Cretaceous of the Atlantic and Gulf Coastal Plain mainly by internal molds, but an incomplete distorted shell was found by Wade at Coon Creek, Tennessee. Shell low, trochiform. Whorls about 4, broad, flattish, gently inclined on the aides. Surface rough and very irregular, due to the agglutination of extraneous shell fragments and other objects. Base broad, flattish, broadly excavated, gently inclined away from the center. The molds suggest a narrow umbilicus, hut this was probably filled by the shell leaving only a rather deep umbilical fissure. The shell from Coon Creek indicates a smooth base except for rather pronounced incremental lines. A cross section of the flattish whorl would present a long narrow opening but the outer lip of the aperture is broadly concave backward making the opening broadly suhovate or nearly circular. The Coon Creek shell exhibits a thin, simple outer lip, and the thin inner lip bends abarply over into the umbilical fissu~e. Dimensions of the medium-sized in­ternal mold shown in plate 52, figures 17-19: Height 17+ mm., diameter 33 mm. The large shell figured by Wade, though too badly crushed for exact measurement, must have been fully 50 mm. in diameter. Internal molds of this genus are f re­f(Oelltly found in the Upper Cretaceous deposits of the Atlantic and Gulf Coastal Plain, but they present no characters that terve as a basis for the recognition of more than one species. Perfect shells might afford evidence of two or more species, and this is suggested by t~e. some­what higher spires of some md1v1duals. Dall could see no differences between Cretaceous, Tertiary, and Recent species which have been described under different specific names, and he referred all . of them to the older Recent species, Xenophora conchyliophora (Born). In the &pecimen which he figures, however,345 the whorls are narrower and more numer­ous and should certainly be diflerentiated from the Upper Cretaceous shells. It seems highly probable that, if well pre­served fossil shells could be found for comparison, the Cretaceous ones could be shown to be specifically distinct from the Tertiary and Recent ones. The Cretaceous genus Eoooptygma, Gabb,346 which is like X eno phora except for a spiral groove on the base of !he internal mold, is based on a feature which may be only a specific, perhaps only a senile, character. Internal molds of Xenophora from the Upper Cretaceous of the Gulf region exhibit a smooth base, but toward the aperture a groove at the position of the one described and figured by Gahb makes its appearance and grows stronger anteriorly, suggesting an adult or old age character. Types.-Holotype, Academy of Natural Sciences of Philadelphia. From the Prairie Bluff chalk at Prairie Bluff, Ala­bama River, Alabama. Plesiotype from Texas, U.S.N.M. no. 76863. Distribution in Texas.-Blossom sand (upper Austin chalk age) : Bed of a small creek, %, mile southeast of the crossing of the Texas &Pacific and Texas Midland railroads, southwest edge of Paris, Lamar County (7508); Forest Hill church, 7 miles northeast of Honey Grove, in Lamar County (9701). Pecan Gap chalk (upper Taylor age) : The Cox place, 3 miles east by south of Wolfe City, Hunt County (9712). Navarro group, Corsicana marl : 1~i miles N. 20° W. of Tona siding ( 15545, 846Dall, W. H., Wagner Free Inst. Sci. Trans., vol. 3, pt. 2, pp. 360-362, pl. 4 (in pt. 1), figs. 10, lOa, 1892. 3'6(;abb, W. M., Aud. Nat. Sci, Philadelphia Proc., vol. 28, p. 302, 1876. The University of Texas Publication No. 4101 figured) ; well 7 / 20 mile south by west of St. Mary's University, Bexar County ( 16353) ; near Castroville (7665). Outside distribution.-Tennessee: Coon Creek tongue of Ripley formation. Mississippi: Prairie Bluff chalk. West-central Alabama: Prairie Bluff chalk. Delaware: Crosswicks clay. New Jersey: Navesink marl. Range.-The distribution in Texas in­ dicates a range from beds of upper Aus­tin age, upward through the Taylor marl and the Navarro group, that is, through the Exogyra ponderosa and E. costata zones. Family TURRITELLIDAE Genus TURRITELLA Lamarck, sensu lato TURRITELLA TRILIRA Conrad Pl. 52, figs. 1-5 1860. Turritella trilira Conrad, Acad. Nat. Sci. Philadelphia Jour., 2d ser., vol. 4, p. 285. 1861. Turritella corsicana Shumard, Boston Sor. Nat. History Proc., vol. 8, p. 196. 1901. Turritella trilineata Hill, U.S.Geol. Survey 21st Ann. Rept., pt. 7, pl. 48, fig. 3. (Figure only.) 1902. Turritella trilineata Hill and Vaughan, U.S. Geol. Survey Geol. Atlas, Austin Folio (No. 76), illustration sheet, fig. 47. (Figure only.) 1906. T urritella trilira Conrad. Well er, Geol. Survey New Jersey, Paleontology, vol. · 4, p. 699, pl. 79, figs. 4, 5. 1906. Turritella trilira Conrad. Veatch, U.S. Geol. Survey Prof. Paper 46, pl. 11 (op. p. 26), fig. 4. (Figure only.) 1916. Turritella trilira Conrad. Gardner, Mary­land Geol. Survey, Upper Cretaceous (2 vols.), p. 489. 1923. Turritella trilira Conrad. Stephenson, North Carolina Geol. and Eron. Survey, vol. 5, p. 360, pl. 90, figs. 2-9. 1926. Turritella trilira Conrad. Wade, U.S.Genl. Survey Prof. Paper 137, p. 161, pl. 56, fig. 3. 1926. Turritella trilira Conrad. Stephenson, Alabama Geol. Survey Sperial Report No. 14, p. 250, pl. 92, fig. 15. (Figure only.) The original of this species was col­lected by Dr. W. Spillman in Tippah County, Mississippi, but the exact locality was not specified. The type was not fig­ured and was subsequently lost. There remains therefore only the author's brief verbal description, quoted below, on which to base an identification: Turreted; whorls with three equidistant, very acute, prominent ribs; revolving lines micro­~copic, closely arranged. Length 2% (?) inches. Although the specimens ordinarily re· ferred to the species include forms that might logically be given a separate recog· nition as varieties, as a whole they con­stitute a compact group, widely distributed in the Upper Cretaceous deposits of At· lantic and Gulf Coastal Plain. The fol. lowing description is based mainly on specimens from Lee's old mill site, 2 miles northeast of Keownville on the road to Molino, Union County, Mississippi. This locality, though now in Union County, was within Tippah County as its boundaries existed at the time Doctor Spillman made his collections. Strati· graphically the locality is in the upper part of the Ripley formation. Shell high, imperforate; the angle of the spire near the tip is about 17 degrees, but the angle increases to about 23 degrees near the middle of the spire of adults, thence, decreases to 14 or 15 degrees near the large end. The protoconch was not seen perfectly preserved, but appears to be a simple, dextral, prominent shell. Whorls 15 or more, probably exceeding 20 in large individuals. The sides of the whorls are broadly rounded and are ornamented with three equally spaced, prominent acute spiral ribs; the whole surface of the larger whorls is further marked by very fine, almost miscroscopic, closely spaced spiral lines which become obscure and fade out toward the apex. On the smaller whorls toward the apex of the spire of many specimens a fourth revolving rib, much less prominent than the other ribs, is present between the suture and the uppermost of the three main ribs; this rib gradually fades out and generally disappears less than midway of the spire; it is unequally developed on different individuals being traceable to the body whorl in some and being entirely absent on others. The suture is closely appressed and typically lies a little below the broad, rather deep sutural channel; the suture is bordered above by a thin, low, slightly overhanging carina; the space between Invertebrate Fossils of the Navarro Group the suture and the first rib below is slightly excavated. The fine lines of growth are strongly concave backward on the sides of the whorls. The base of the shell was not seen in the Tippah County material, but on specimens from other localities, especially Eufaula, Alabama, it is flattish and almost at right angles to' the outer surface; the forward edge of the body whorl is bordered by a sharp carina which simulates a fourth rib, and this carina is closely bordered on the base by a shallow channel; obscure re­volving lines appear on the base of some specimens; the growth lines on the base are broadly concave toward the aperture. The aperture is subcircular to broadly subovate, and on adults flares slightly; the lips are thin to moderately thick; on young individuals the inner lip forms a thin callosity on the base but on adults this Iip rises free from the base. Large shells from Eufaula, Alabama, attain a height of 70 mm. and a diameter of 20 mm. The Texas shells are essentially like those from Mississippi, except that on most specimens the fine spiral lines are so weakly developed that they can scarcely be seen even under a lens; but in a good light at a favorable angle they are gen­erally faintly discernible. .An occasional specimen, however, shows the fine lines almost as strongly developed as they are on the Mississippi shells. Some of the Texas shells attain an estimated height of 85 or 90 mm. and a diameter of 23 mm. Turritella quadrilira Johnson, T. trilira Conrad, and T. bilira Stephenson form a closely related, probably evolutionary group, of which the first is restricted to the Exog)'ra ponderosa zone, the second ranges through the E. ponderosa and E. costata zones, and the third occurs only in the uppermost beds of the E. costata zone. Types.-The holotype of this species, which should be in the Academy of Natural Sciences of Philadelphia, is ap­parently lost; it was collected by Dr. W. Spillman in Tippah County, Missis­sippi; it was never figured. The specimen figured by Stephenson3·1i from Bullock's old mill near Dumas, Tippah County, Mississippi, shows an immature fourth rib below the suture, and since this feature was not mentioned in Conrad's original description, this specimen can not be re­garded as strictly typical. The two speci­mens ( plesiotypes) shown in plate 52, figures 3, 4, of the present paper (U.S.N.M. no. 7686--t) are from the Ripley formation at Lee's old mill site in Union County (formerly a part of Tippah County), Mississippi; for all practical purposes they may be regarded as neo­types, although they can not be known to be from the same locality and stratum as the holotype. Plesiotypes from Texas, U.S.N.M. nos. 76865, 76866. Distribution in Texas.-Wolfe City sand member of Taylor marl: Near the G.C. & S.F. R. R. about 4if> mile east of Pecan Gap, Delta County ( 9713) ; cut of Santa Fe R. R., 1~~ miles northeast of Wolfe City, Hunt County (9562); cut of G.C. & S.F. R. R., about 2 miles east by north of Wolfe City (9709). Anacacho limestone: The King water hole on Hondo Creek, about 3 miles north by west of Hondo, Medina County (7680) ; Medina River at the bridge at Castroville, Medina County (7664). San Miguel formation: Carter ranch, 12 miles by road northwest of Eagle Pass, Maverick County ( 8227) ; ?on the Del Rio road, 12.5 miles northwest of Eagle Pass ( 1513) ; northward-facing slope of Agua de Fuera Creek valley, about 5 miles southeast of Spofford, Kinney County (8262). Navarro group, Neylandville marl: 3~~ miles west-northwest of C o r s i c a n a ( 16166) ; 21/2 miles north of Corbet (16170, Tex. Bu. 17300); ?21;2 miles south of Ben Hur (15543). Navarro group, N acatoch sand: 3 miles north of town of Sulphur Bluff (5322); vicinity of Kaufman (761) ; 21h miles north of Corsicana ( 14114.) ; vicinity of Chatfield ( 762~ 1 specimen figured) ; loose pieces of rock in street at Chatfield ( 7568) ; %, mile east of Chatfield (7571) ; 317Stephenson, L. W., North Carolina Geol. and Econ. Survey, vol. 5, pl. 90, fig. 9, 1923. The Uniz·ersif y of Te.ras Publication No. 4101 3 5 to ·l-~ milP northea~t of Chatfield ( 7572. 11117 l: fi(·'ld south of Chatfit>ls northeast of Corsicana t9515 l : \\'atkins· place 3 miles north of Corsicana I 9552 l : north edge of Corsicana I 518. l specime"n figured l : -1 miles north of Corsicana (17366) : ,-icinity of Corsicana t763) : road 5 miles south-southwest of Corsicana l 7573 ., : 5 miles northeast of ~kClanahan l 17371). \ anuro group. Corsicana marl: :\bout 5 miles east lff north of GreenYille I 1292-t I. Outside distribution. - :\ r k ans as: Brownstown marL Saratoga chalk~ and \acatoch sand. Tennessee: Coon Creek tongue of Ripley formation. ~Iississippi: Coffee sand~ Ripley forma­tion. and Owl Creek formation. Central and west-central .Alabama: Prairie Bluff chalk. East-central Alabama and Chattahoochee 1egion (Alabama -Georgial: Blufftown formation. Ripley formation, and ProYi­dence sand. \orth Carolina: Snow Hill member of Black Creek formation; Peedee formation (upper part). Maryland: :Matawan formation and ::\Ionmouth formation. \ew Jersey: Wenonah sand. Range.--In Texas the species ranges from beds of Taylor age upward to the Corsicana marl of the .\"aYarro group. In general in the Atlantic and Gulf Coastal Plain the range of the species is through the zones of Exogyra ponderosa and E. costata. TURRITELLA BILIRA Stephenson, n.sp. Pl. 52. fig~. 9-16 This species is based on well presen-ed material from near the top of the Ripley formation t C pper Cretaceous I exposed on Pataula Creek. ClaY Count\-. Georcria. . . c Shell of small to medium size for the genus. .-\pical angle 28 or 30 degrees~ de­creasin~ to about 20 de~rees on the lar(Yer ~ ~ c whorls below. Whorls about 12 l esti­mated I in a specimen the size of the in­('Omplete holotype. Protocl)nch not pre­serYed. but ob\·ioush· wry small. Suture closely appressed lying a little below the middle of a deep. broadly U-shaped chan­twl: thi~ channel is noticeably \vider on sonw inB77. Distribution in Texas.-Navarro group, Neylandville marl: 3·~~ miles west-north· west of Corsicana (16166) ; 21h miles north of Corbet (16170, type lot; 17365). Navarro group, Nacatoch sand: ?Vicin­ity of Kaufman (761). TURRITELLA VERTEBROIDES JONESI Stephenson, n.var. Pl. 53, fig. 11 Shell large, elongate-conical; spiral angle probably 17 or 18 degrees at the apex, spreading slightly toward the front. Suture closely and neatly appressed. Sides of whorls broadly convex. The larger whorls are ornamented with 4 pri· mary spiral ribs, the first, second and third of which are moderately thick, prom· inent, and round crested, and the fourth of which is smaller and sharper; num· bered from rear to front the first and sec· ond primary ribs are a little more widely spaced than the others; centrally in each of the spaces between the primary ribs is a secondary rib, and in each of the subspaces is a tertiary rib; the secondary and two tertiary ribs between the second and third primaries are more widely spaced than the corresponding ribs in other interspaces; the first secondary be· low the suture approaches a primary in strength; still finer, almost microscopic lines complete the ornamentation over practically the entire surface of the larger whor Is; the ornamentation b e c o m es weaker posterioriy, and the whorls, 1.0 mm. or less in diameter, appear to be practically smooth. A sharp, moderately prominent carina bounds the periphery of the body whorl; a shallow channel hor· ders this carina, but otherwise the base is nearly flat and descends abruptly to the columella. The aperture is not well pre· served in the available material but is probably subcircular or broadly subovate. The body whorl of large individuals tends to separate from the penultimate whorl, causing the inner Ii p to rise free from the base of the shell. Invertebrate Fossils of the Navarro Group Dimensions of the holotype, in which only the six larger whorls are preserved: Height 64 + mm., diameter 23 mm. This variety differs from T. vertebroides Morton in the greater irregularity in the spacing of its spiral ribs; only the larger end of the type of Morton's species is pre­served and it is badly crushed. Compared with T. vertebroides tenuispira, jonesi has a stronger ornamentation medially and anteriorly, and a weaker ornamentation posteriorly, the whorls toward the apex apparently becoming smooth. Types.-Holotype, U.S.N.M. no. 76878; named for the Hon. Anson Jones, Presi­dent of the Republic of Texas, 1844-1846. Distribution in Texas.-Navarro group, Kemp clay: West of Zuehl (7721); 2 miles south-southeast of Schumansville (16668); near Deatsville (764); 3V1 miles east by north of Manor (1386L type loc.) ; 1 mile west by south of Odds ( 17373) ; branch 6~h miles southwest of Currie (14139). TURRITELLA VERTEBROIDES LONGI Stephenson, n.var. Pl. 53, figs. 12, 13 This variety is much like T. vertebroides jonesi but is a more slender, elongated form, having the posterior part of the whorl more flattened, and the sutural de­pression wider and shallower. Between the first and second of the four primaries are two secondary ribs, the posterior one the stronger, and in the sub~paces formed by these secondaries are weak tertiaries. The variety is distinguished by its slender­ness, having an estimated apical angle of only about 12 degrees. The broken holo­type includes 4 whorls at the large end of a shell having an estimated height of about 110 mm., and a measured diameter of 22.5 mm. The shell has a flattish base hounded on the periphery by a narrow, prominent carina, and in this respect is typical of the vertebroides group. Accompanying the holotype is a frag­ment of a Turritella which includes 3 whorls, with a maximum dinmeter of 12 mm.; the sides of the whorls appear to he smooth. This fragment may or may not belong to the variety longi. Holotype.-U.S.N.M. no. 76880; frag­ment, U.S.N.M. no. 76879. Named for James Long who, in 1810, led a filibuster­ing expedition into Texas to aid the State in becoming a republic. Distribution in Texas.-Navarro group, Kemp clay: 2 miles northwest of Deats­ville (14128) ; 2 2/5 miles southeast of Manor (18196). TURRITELLA VERTEBROIDES LEONI Stephenson, n.var. Pl. 53, fig. 10 In general form and sculpture this variety resembles T. vertebroides jonesi, but the primary ribs are much coarser and the secondary and tertiary ribs, which are poorly preserved, are consequently more crowded in the narrower inters paces; the sutural depression is also narrower. The variety is based upon three incomplete specimens of which the larger one is desig­nated the holotype; the latter includes about 41;2 of the larger whorls, with the body whorl and base partly broken away. The shell has the characteristic flattish base of the vertebroides group. The apical angle appears to be about 16 degrees, the height of the restored shell about 85 mm., and the measured diameter 20 mm. Holotype.-U.S.N.M. no. 76881; 1 un­figured paratype, U .S.N .M. no. 76882. Named for Alonzo de Leon who, with Padre Manzanet, founded Mission San Francisco de las Tejas, near Neches River, in the year 1690. Distribution in Texas.--Navarro group, Kemp clay: 3114 miles east by north of Manor ( 13861, type locality). TURRITELLA AUSTINI Stephenson, n.sp. Pl. 54, figs. 4-Q Shell thin, of moderate size, elongate­conical, with an apical angle of about 18 degrees. Sides of whorls plumply rounded, fullest below. Suture closely appressed and occupying a deep depres­sion, the upper or posterior slope of which is the steeper. The ornamentation con­sists of 8 or 9 narrow, sharp, nonprom­inent, spiral primary ribs, with smaller, t'qually sharp. s~condary ribs in the inter­spaces: the ohscure lwginnings of tPrtiary ribs may be faintly seen in places in the smaller subspaces: fine. sharp ribs of sec­ondary and tertiary strength produce a fine lining on the opposing slopes of the sutural depression: there is '3ome uneYell­ness in the spacing of the spirals. the anterior ones being a little more widely spaced than the posterior ones. The base is flattish. descending abruptly to the columella. and appears to be nearly smooth. although fine. obscure. micro­scopic. spiral lines may be faintly seen on one specimen: the base is bounded at the angular peripher~-by a sharp, mod­ffately prominent carina. The aperture is not well presen·ed. The dimensions of the holotype~ an in­rnmplete specimen sli~htly distorted by a calcite Yein. are: Height 23 + mm.• diameter 11.5 mm. The largest paratype has a diameter of 13 mm. The species is characterized bv the plumpness of the whorls and by th~ fine~ sharp. subregular system of spiral lir:Je. The only other described T urritella in the Coastal Plain~ comp3rable to this one, i~ T. houstoni. a species with flattish whorls. a subrounded periphery. and a distinctly ornamented base. The two species occur together at their t~-pe localit\·. Types.-Holotype. LS.\".:'.\I. no. 76883: 1 figured paratype~ LS.\.\I. no. 7688-l: 5 fr a gm en tar y. unfigured paratypes. LS.\.:'.\I. no. 76885. \amed for Stephen f. Austin. a Texas leader during and be­fore the time of the Hepublic. Distribution in Te.ras.-\ayarro group~ \acatoch ~and: 3 5 to t--~ mile northr:-ast of Chatfield I l-1-117. type loc.) : Yicinity of Chatfield I 762 l: :~-1 milP east of Chat­field (7571'1. TURRITELLA HOUSTONI Stephenson, n.sp. Pl. 5-t figs. 1-3 Shell of moderate size and thickne8s. elongate-conical. with an apical an~le of about 22 degrees. ~ides of whorls flattish to slightI y conca,-e m upper or posterior half, swelling to a gentle bulge in the lower half. Suture closely ap­pressed: suturnl depression moderately deep. The !"-urface is ornamented with 9 primary spiral ribs which are of mod­erate but unequal strength, and between the primaries are smaller, but distinct, secondaries~ faint tertiaries appear in places on some specimens; the primaries are strongest and most widely spaced on the anterior bulge of the whorl, and are closest together in the slight constriction just aboYe the middle of the whorl. The periphery of the body whorl is sub­rounded, but passes into a steeply de­scending flattish base; the periphery bears two moderately strong spirals separated by a smooth interspace~ the base is nearly as strong}~· ornamented as the sides, the spirals including 7 or 8 primaries, weaker intermediate s e c o n d a r i e s, and faint tertiaries in the subspaces. The growth lines on the sides of the whorls are dis­tinctly concaYe toward the aperture, but are a little sinuous where they cross the anterior bulge. The aperture is not pre­serYed. Dimensions of the incomplete holo· type: Height 22 + mm., diameter 9.5 mm. The largest specimen in the collec· tion has a diameter of about 15 mm. This species is ornamented much like T. austini, with which it is associated, but the spirals are stronger, the sides of the \rhorls are markedly flatter, the periphery is subrounded, and the base is distinctly ornamented. T. mcnairyensis \Vade, from the Coon Creek tong~e of the Ripley formation at Coon Creek, Tennessee, is a closely analogous species, but its whorls are not so flat, its sculpture is stronger, and its peripheral angle and base are more plumply rounded. Holotype.-U.S.N.M. no. 76886. Named for the Hon. Sam Houston, President of the Republic~ l 8-t.1-1844, and Governor of the State of Texas, 1859-1861. Distribution in Texas.-Navarro group, \acatoch sand: 3 5 to -~,t mile northeast of ChatfieId ( 75 72: 1-111 7 tvpe lot) · field ' " ' south of Chatfield (7569) ; vicinity of Kaufman (761). Invertebrate Fossils of the Navarro Group TURRITELLA DEATSVILLENSIS Stephenson, n.sp. Pl. 52, figs. 6-8 Shell small, turreted, apical angle about 24 degrees. Whorls 6, rather strongly convex on the sides; protoconch broken away. Suture closely appressed, situated at the bottom of a wide, deep, asymmetric depression, the shorter slope of which is above the suture. Each whorl is orna­mented with 3 rather strong, sharp, pri­mary lirae, the center one of which is slightly the more prominent; between the two lirae farthest forward is a small, ob­scure secondary. The peripheral angle of the body whorl is angular, and bears a prominent, narrow ridge; the base is flattish, smooth and descends sharply to the columella. Dimensions of the holotype: Height 17 mm., diameter 7 mm. The three sharp lirae of this species suggest relationship to T. trilira Conrad, from which the species differs in having a wider apical angle, and a secondary lira between the second and third primaries. The holotype is much smaller than trilira, but it may be a young shell. A second specimen which occurs with the holotype, has the same general form and the same wide, deep, asymmetric sutural depression, but has four instead of three about equally strong lirae; it is questionably referred to this species on the supposition that it may be an in­dividual variant; in the absence of a large suite of specimens showing intermediate forms it might reasonably be regarded as a separate variety, or perhaps even a dis­tinct species. Types.-Holotype, U.S.N.M. no. 76887; 1 figured example (?) U.S.N.M. no. 76888. Distribution in Texas.-Navarro group, Kemp clay: Near Deatsville (14125). Unidentified specimens of TURRITELLA Two fragments of a moderately large species of Turritella from the Corsicana marl, at the crest of a hill south of the Seguin-San Antonio highway, 21h miles west of McQueeney, Guadalupe County ( 15523) , probably represent a new species, but are hardly well enough pre­served to serve as types (pl. 54, fig. 8) . The sides of the whorls are fiat, and the sutures are closely a ppressed and are very narrow and shallow; the sculpture con­sists of 12 or 13 small, non prominent, primary spirals, with very fine, almost obscure secondaries in the interspaces. The species resembles T. subtilis from the upper part of the Peedee formation of North Carolina, but has a less deeply sunken sutural depression and a somewhat more regular alternation of large and small spiral costae. U.S.N.M. no. 76889. Several young gastropods from the Kemp clay on Colorado River at Webber­ville, Travis County (7601, 1 specimen figured, U.S.N.M. no. 76890), and be­tween depths of 675 and 800 feet (13132, U.S.N.M. no. 76891; 13124, U.S.N.M. no. 76892) in Cargile No. 1 well of the Robinson Oil & Gas Company, 2 miles west of Groesbeck, Limestone County, appear to represent a new species of Turritella. The best preserved shell (pl. 54, fig. 7) is from the first-named locality. It is a small thin shell, having an apical angle of 18 degrees, with 8 whorls and a badly broken protoconch. The closely appressed suture is at the bottom of a deep, wide asymmetric sutural depression, the posterior side of which is the steeper. The sculpture on the larger whorls con­sists of 4 sharp, spiral lirae with small secondaries in the inters paces; on the posterior slope of each whorl are 3 small lirae, the central one of which is the larger; on the anterior slope between the fourth primary and the suture is another small lira. The base is flattish, is bor­dered by a sharp carina, and is or­namented with 7 or 8 fine, evenly spaced lirae; the aperture is broken but appears to be broadly subovate; the inner lip forms a thin polished callus over the base of the shell. Dimensions: Height 8 mm., diameter 2.5 mm. This specimen is ex­cellently preserved and were it not probably a juvenile example it would serve well as a type. Imperfectly preserved specimens of Turritella, which prohably represent varie­tal forms of T. vertebroides Morton, hut which are specifically unidentifiable, have The University of Texas Publication No. 4101 been collected at the localities indicated below. Distribution ~n Texas.--Navarro group, Corsicana marl: 1+fl miles N. 20° W. of Tona siding (155-1-5, U.S.N.M. no. 76893); west of Kaufman (754.8, U.S.N.M. no. 7689-1) ; fuller's earth pit, 14 miles west of San Antonio, Bexar County ( 15520, U.S.N.M. no. 76895) ; Castroville road, 1~/> miles west of Leon Creek, Bexar County (15522, U.S.N.M. no. 76896). Navarro group, Kemp clay: Webber­Yille (7601, U.S.N.M. no. 76897). Family CERITHIIDAE Genus CERITHIUM Bruguiere CERITHIUM SIMPSONENSE Stephenson, n.sp. Pl. 54, fig. 9 Shell small, elongate-conical, apical angle 22 degrees. The protoconch is a simple, smooth dextral cone, having about the same angle of diyergence as the main shell; the latter includes 8 regularly in­creasing flat-ribbed whorls. Suture closely appressed, occupying a sharply impressed depression. The sculpture consists of numerous, rather fine axials which on the larger whorls are crossed by four mod­erate! y strong, flat-topped spirals, the posterior one of which is narrower than the others; on the body whorl the inter­s paces are as wide as, or wider than, the spirals, but the spirals tend to become more cro,-.,·ded posteriorly; the first and third spirals in front of the suture become weaker as they pass backward, and prac­tically disappear before reaching the protoconch; the crossing of the axials and spirals produces a regular, beaded pattern. The peripheral shoulder on the body whorl rounds rather sharply into a flattish base which descends abruptly to the colu­mella; the periphery is marked by a carina which is weaker than the spirals above; the base is ornamented with 6 or 7 spirals which become progressively weaker from the shoulder inward to the columella. The aperture is not preserved. Dimensions of the holotype: Height 7.5 mm., diameter 2.5 mm. Holotype.-l7.S.N.M. no. 76898. Distributfon in Texas-Navarro group, Nacatoch sand: Road 2 miles southwest of K~rnfman (75·"16). CERITHIUM sp. Pl. 5-l, fig. 10 One young individual of Cerithium, probably an undescribed species, was found in the Kemp clay at a depth of 730 feet in Cargile No. 1 well of the Robinson Oil & Gas Company, 2 miles west of Groesbeck, Limestone County ( 13132). The shell is small and has an apical angle of about 18 degrees. The suture is closely appressed and occupies the bottom of an asymmetric depression the posterior slope of which is the steeper; the whorls are traversed by two spirals separated by a flat, rather broad interspace; the anterior spiral is rather coarsely, though not prominently noded, and is closely paral­leled on either side· by fine threads; the posterior spiral is smaller and smoother than the anterior one, and is only oh· scurely noded; the interspaces bordering the spirals are rather coarsely and oh· scurely undulating. A strong, smooth carina marks the peripheral angle and the flattish base is ornamented with fine spiral threads. The body whorl is broken awav for more than half its length. Only ~ fragment of the larger end of the proto· con;h is preserved; it indicates a simple, polished dextral shell. Dimensions: Height about 5.5 mm., diameter about 2.25 mm. U.S.N.M. no. 76899. Genus NUDIVAGUS Wade NUDIVAGUS? COOPERENSIS Stephenson, n.sp. Pl. 54, figs. 11, 12 Shell large, simple, turreted, spiral angle about 30 degrees. Whorls 6 as preserved, with 3 or 4 missing at the apex. Whorls \'ery broadIy convex on the side, slightly constricted below the suture. Suture closely appressed. Surface smooth to the naked eye, but under the microscope fine, closely spaced spiral lines appear in a band below the suture, and similar lin~ can be faintly seen elsewhere; the ap· parent absence of these lines on parts of the surface is probably due to the poor Invertebrate Fossils of the Navarro Group atate of preservation of the shell. The periphery of the body whorl is broadly rounded; on the side of the body whorl just back of the aperture the base descends gradually to the beginning of the anterior canal where there is a sharp constriction. The aperture is elongated, is acutely angular at the rear, and passes into an elongated canal in front; the latter is broken away, but in the type species from Coon Creek, Tennessee, it is narrow, of moderate length, and noticeably sinuous. The outer lip is broken away; the inner lip is imperfect, but is broadly excavated and forms a thin coating of callus. Dimensions of the incomplete holotype: Height 57+ mm., diameter about 20.5 mm. The description is based on one im­perfect shell, which differs from N. limplicius Wade, from Coon Creek, Ten­nessee, in the greater convexity of the whorls, and in the apparent weakness of the fine microscopic spiral lines. Holotype.-U.S.N.M. no. 76900. Outribution in Texas.-Navarro group, 1ieylandville marl: 2/5 mile north of Cooper ( 14063) . NUDIVAGUS 7 •P· Pl. 54, figs. 13, 14 A small internal mold with the shell adhering over most of the body whorl, from the Nacatoch sand on Postoak Creek at the north edge of Corsicana, Navarro County (518), appears to belong to Nudivagw. It is similar to N. cooperensis, but the spire is less slender, having an apical angle of about 38 degrees, and the sides are less rounded. The surf ace of the shell where preserved is covered with numerous, obscure, microscopic threads. The specimen probably represents an un­descrihed species, but is considered too incomplete to serve as a type. U.S.N.M. no. 76901. Family APORRHAIDAE Genua ANCHURA Conrad, aenau Jato Type species.-Anchura abrupta Conrad.848 lilComad, T. A., Acad. Nat. Sci. Philadelphia Jour., 2d -.. TOI. 4, P• 284, pl. 47, 61. 1, 1860. Anchura abrupta Conrad is the type of this genus by monotypy, and Cossmann849 is in error in citing another species as type. The genotype of this species is a large, plump, regularly sculptured gastropod, having a long, slender anterior canal and a Iip expansion which for ks into two parts, one a long, thick, tapering spur-like projection curving outward and upward and the other, a much shorter projection extending outward and downward. Many species differing markedly in form, sculp­ture, and in the character of the lip ex· pansion have been included in the genus and it is to be expected that when this cosmopolitan group has been critically studied it will be subdivided into several genera and subgenera. The material available to the writer does not seem ade­quate to justify an attempt to reclassify the group. ANCHURA NOACKENSIS Stephenson, n.sp. Pl. 55, figs. 6, 7 Shell large, thick, turreted. Suture closely appressed and only moderately impressed. Three of the larger whorls, including the body whorl are preserved in the holotype. Spiral angle about 40° ; apex more slender. Number of whorls 10 or more. The sides of the whorls above the body whorl are moderately convex in the anterior two-thirds and strongly con­stricted in the posterior one-third border· ing the suture. The sculpture includes both axials and spirals. On the penul­timate whorl there are 24 moderately thick and prominent axials, each a little nar­rower than the adjacent interspaces; the trend of the axials forms an asymmetric curve, concave toward the front, the strongest part of the curve being on the constricted posterior band. The spirals are 8 in number, are moderately strong, are of unequal thickness and spacing, and form bluntly rounded nodes at their in­tersections with the axials; the two pos­terior spirals occupy the constricted band, and are more widely separated than the others; the closest spacing of the spirals 8'9Co11mann, M., Euala Pateoc. Comp. 6th Liv., p. 92, 1904. The University of Texas Publication No. 4101 is on the crC'st of the more swollen an­terior part of the whorl. The body whorl rounds broadIy down from the pc>ri phery to the columella; the base bears 5 primary ~pirals of unequal prominence and spac­ing, the two posterior ones of which are the stronger and the more widely spaced, and are separated by an interspace bearing a weak secondary spiral; the other three spirals become progressively smaller toward the columella. Numerous, ob­scure, spiral threads appear in places on the better preserved parts of the surface and probably a perfectly preserYed shell would exhibit these threads over the greater part of its surface, including the interspaces, axials and spirals. The aper­ture is narrowly subovate. On the holo­type the outer lip is broken away, hut, approaching the aperture, the shell shows the characteristic generic expansion and divergence of the ribs, and doubtless the complete shell would exhibit an expanded birostrate lip such as that possessed by the type species, A. abrupta Conrad. The inner lip forms a thick callus on the base of the body whorl, and is deeply and broadly notched where it intersects the columella. The posterior or anal channel is moderately impressed; the anterior drnnnel is broken away, but may be as­sumed to form a narrow, great!y extended spine-like projection. Dimensions: Holotype, height 60+ mm., diameter about 34 mm.; paratype, height s.i+ mm., diameter 35 mm. This species is closely related to the type species, A. abrupta Conrad, from Tippah County, l\lississippi. It is larger, more coarsely sculptured both with respect to the axials and spirals, is more strongly constricted on the posterior part of the whorls~ and differs in numerous minor details of sculpture. Anchura su bstriata \Vade, a smaller species, is less constricted on the posterior part of the whorl, and has 6 instead of B spirals on the penultimate whorl. A. lamari. a nearl\' related Texas ~peeiPs, has fewer axial~ and spirals, the axials are thicker and there are minor clif­ferences of scu I pture. The posterior part of the whorl is also less strongly con­stricted. Types.-Holotype, U.S.N.M. no. 76902; paratype. U.S.N.M. no. 76903. /Jistrilmtion in Te.ras.--Navarro group, Kt·mp day: :~ mile~ S. ~m0 W. of Thrall {155:r7. holotypc; l7:HO, paratype); '!San Gabriel Hiver. 2 ·5 mile above San Gabriel (14130). ANCHURA LAMARI Stephenson, n.sp. Pl. 55, figs. 1-3 SheII rather large, turreted, apical angle about 22 degrees. Protoconch not pre· served. Suture closely appressed, mod­erately impressed. Whorls 10 in the holotype, slightly convex on the anterior half of each whorl, flattening out pos­teriorly toward the suture. The axials are thick and moderately prominent on the most inflated part of the whorl, but he· come weaker both toward the front and rear; they number 22 on the body whorl and 19 on the penultimate whorl; the trend of the axials is a little concave to· ward the aperture, the deepest part of the curve being ubout midway of the width of the whorl. On the antepenultimate whorl are 6 spirals, but on the penultimate whorl the posterior margin of the body whorl has overriden the sixth spiral, leav· ing only 5 exposed; the spirals are of subequal strength, but tend to be a little stronger and a little more closely crowded on the most inflated part of each whorl. The intersecting of the axials and spirals produces a distinct, rather coarse noding, but the first spiral below the suture is more finely noded than the others. The base exhibits 7 nearly smooth spirals; the second spiral below the periphery is the strongest of the seven, in front of which the spirals become successively narrower and weaker toward the columella, the last one being very faint. Numerous fine spiral threads are present over the entire outer surface of the shell. The aperture is broken away on the holotype, and the thinness of the inner Iip suggests that this shell has not reached maturity; one speci· men from the type locality, though no larger than the holotype, possesses a thick inner lip, notched centrally, and the pos· terior portion of an expanding, thick outer lip which is mostly broken away. Two Invertebrate Fossils of the Navarro Group incompletely preserved specimens from near Chatfield show a greatly extended expanding, broad, thick outer Iip similar to that of A. abrupta Conrad; the fourth spiral in front of the suture of the body whorl continues out onto this lip, curving upward toward the base of the long, up­ward, spinose projection which, though broken away in the available material, doubtless would be present in perfect shells, as it is in A. abrupta; at the outer lower extremity of the lip is a short, blunt downward projection; two or three of the spirals in front of the fourth one die out as they pass forward onto the lip, but the surface of the lip is further ornamented with obscure, fine threads. The anterior canal lacks these threads. Dimensions of the incomplete holotype: Height 68+ mm., diameter 27.5 mm. This species is closely related to A. noackensis, but is smaller, has fewer axials and spirals, thicker axials, and a less pronounced constriction on the posterior part of the whorl. It is also closely related to A. abrupta Conrad, but is more coarsely sculptured. Compared with A. substriata Wade the species is more coarsely sculptured and the spirals on the base are smoother and less numerous. Types.--Holotype, U.S.N.M. no. 76904; 5 incomplete, unfigured p a r at y p e s, U.S.N.M. no. 20986. Named for the Hon. Mirabeau B. Lamar, President of the Republic of Texas, 1838-18:!0. Distribution in Texas.-Navarro group, Nacatoch sand: 4 ~~ miles east by north of Rosali ( 14061) ; vicinity of Kaufman ( 761, type loc.) ; road 2 miles southwest of Kaufman ( 7546) ; vicinity of Chatfield (762); field south of Chatfield (7569) ; %, mile east of Chatfield ( 7571). ANCHURA BEXARENSIS Stephenson, n.sp. Pl. 55, figs. 4, 5 Shell of moderate size, turreted, apical angle about 30 degrees. Suture closely appressed, moderately impressed. Whorls 5 in the incomplete holotype, slightly con­vex on the sides, a little constricted pos­teriorly below the suture on the larger whorls. The axials are of moderate thick­ ness and prominence, but are narrower than the inters paces; on the largest whorl the axials number 15 and on successively smaller whorls respectively 18, 20 and 24. As in other similar species the trend of each axial forms a curve broadly concave toward the aperture; on the largest whorl the axials end abruptly at the periphery. On each of the larger whorls are 8 pri­mary revolving ridges which override the axials; the still smaller spirals are not very clearly preserved but in each inter­s pace is one, or in the wider ones two, secondaries, and in places tertiaries can be detected in the smallest interspaces. The periphery of the largest whorl, which presumably is the body whorl of an im­mature specimen, is subobtusely angular and the base descends steepIy to the columella; on the base are 4 or 5 widelv spaced, primary revolving ridges which become successive! y smaller from the periphery downward, and in the inter­spaces are numerous fine riblets which are not clearly preserved. The aperture is moderately wide but is somewhat elongated, and passes anterior! y into a siphonal canal whose anterior portion is broken away and is therefore of unde­termined length. Dimensions of the incomplete holotype: Height 37+ mm., diameter 16.5 mm. In the matrix with the holotype was found the apical portion of a shell, prob­ably this species, with the protoconch and 3 or 4 additional whorls, all poorly pre­served. The axial sculpture on the two larger whorls is fine and closely spaced and traces of fine revolving ridges may be seen. The protoconch is small and a p­parently simple. This species is closely akin to A. lamari, but is more finely sculptured with respect to both the axials and spirals. The species is also close to A. abrupta Conrad, from the Ripley formation in Tippah County, Mississippi. The type of the latter is, however, lost and its exact locality in Tippah County is not known, so that ttn exact comparison cannot be made with that species. A. bexarensis is more closely similar to one shell from Owl Creek, 2~"2 miles northeast of Ripley, Tippah County, The University of Texas Publication No. 4101 than to specimens from other localities in that county. Types.-Holotype, U.S.N.M. no. 76906; 1 unfigured paratype?, U.S.N.M. no. 76907. Distribution in Texas.-Navarro group, Kemp clay: West of Zuehl (7721) . ANCHURA? LOBATA Wade Pl. 56, fig. 15 1926. Anchura lobata Wade, U.S.Geol. Survey Prof. Paper 137, p. 150, pl. 52, figs. 11, 12. Shell of medium size and thickness. Spire about half the total height of the shell. Whorls seven, slightly convex on the sides, slightly constricted just below the suture, the constriction becoming most pronounced on the penultimate whorl and the body whorl. Suture closely appressed and only moderately impressed. Proto­conch as seen on the holotype, small, smooth, trochoid, dextral, coiled three times. The penultimate whorl is orna­mented with about 19 somewhat unequal, conspicuous axial ribs whose sides slope moderate!y forming interspaces wider than the ribs, and whose bottoms form rather sharply concave troughs; most of the ribs are subangular on their crests, but every eighth to tenth rib is a broad, round­crested varix of medium prominence; the ribs become progressively weaker and de­crease in number toward the apex; pass­ing from the penultimate to the body whorl the axial ribs become wider apart, at first extending well down over the base, but toward the outer, expanded lip be­coming abbreviated and subnodose toward the upper ends; below these short ribs the surface appears smooth and slopes off gently toward the anterior extremity; the whole surface of well preserved shells is covered with delicate, spiral threads so fine they cannot be seen with the unaided eye; these are not wanting on the body whorl of the type, as stated in the original description, although they are more weakly developed, and less completely preserYed there than on the spire. Body 'vhorl broadly rounded on the periphery, becoming constricted and smooth an­teriorly, and passing into a straight, very narrmv canal, which is almost pointed at the terminus. Aperture elongated, pro· duced in front into a long, nearly straight, narrow canal, and less strongly produced posteriorly into a subangular anal canal. The outer lip expands into a broad wing which in the holotype is produced at the outer, upper extremity into a sharp spur, and at the outer lower extremity into a duller, somewhat retreating spur. The upper margin of this wing is produced upward completely across the penultimate whorl; in more mature specimens than the type the margins of the wing become greatly thickened, destroying the sharpness of the spurs. The inner lip is broadly excavated and forms a thin polished callus which spreads conspicuously forward over the base for 5 or 6 mm. from the aper­ture, and upward past the anal canal to and beyond the suture. The Texas shell, although less per· fectl y preserved, agrees in all essential respects with the holotype in size, form and sculpture. Both it and the holotype suffered severe injury shortly before reach­ing the adult stage, and each succeeded in healing the broken shell and in develop· ing an expanded outer lip. Dimensions of the Texas specimen shown in plate 56, figure 15: Height 47.5 mm., diameter, including outer lip, about 29 mm., exclusive of outer lip, 18.5 mm. This species belongs to a closely re· lated group of species and varieties, of which Rostellaria rostrata Gabb,360 from Burlington County, New Jersey, was the first described. One other species and one varietal form from Texas are de· scribed on subsequent pages. Close analogues of this species are Lis podesthes schlotheimi (Roemer) from the Cretaceous of the Aachen district (Germany), as figured by Holsapfel,m and Dicroloma (Perissoptera} bailyi (R. Etheridge, Jr.) from the Cretaceous of Pondoland, South Africa, as figured by Rennie.352 Neither of these appears to 850Gabb, Wm. M., Acad. Nat. Sci. Philadelphia Jour., 2d ser., vol. 4, p. 390, pl. 68, fig. 7, 1860. 3:>1Holzapfel, Edward, Die Mollu3ken der Aacher Kreide: Palaeontagraphia, Band 34, p. 118, pl. 12, figs. 11-13, 1888. 852Rennie, John V. L., New Lamellibranchia and Gastropoda from Upper Cretaceous of Pondoland, etc.: Invertebrate Fossils of the Navarro Group belong to the genus or subgenus to which it is assigned. Types.-Holotype, U.S.N.M. no. 32925, from the Coon Creek tongue of the Ripley formation at Coon Creek, McNairy County, Tennessee. One plesiotype from Texas, U .S.N .M. no. 76908. Diltribution in Texas.-Navarro group, Nacatoch sand: Vicinity of Kaufman (761). 01'Uide distribution.-Tennessee: Coon Creek tongue of Ripley formation. Mississippi: Ripley formation. Range.-In Texas known only from the Nacatoch sand of the Navarro group. In Mississippi and Tennessee ranges through the Ripley formation (lower and middle parts of Exogyra costata zone) . ANCHURA? LOBATA MEDIA Stephenson, n.var. Pl. 55, figs. 8-10 This varietal form is like A. lobata Wade in all essential respects, except that the axial ribs are somewhat more numer­ous and are sharply developed farther back toward the apex, the constriction below the suture is a little more pro­nounced, and the average size is somewhat smaller. These differences hold good among a suite of over 20 specimens. The variety is intermediate in size and in the coarseness of its ornamentation between the typical A.? lobata and A.? elegans. Dimensions of the holotype, which is incomplete at the apex and has part of the outer lip broken away: Height 34+ mm., diameter exclusive of the outer lip about 12.5 mm. Dimensions of the small para­type shown in plate 55, figure 10, which is also incomplete at the apex: Height 24+ mm., diameter, including the ex­panded outer lip, 19 mm. Types.-Holotype, U.S.N.M. no. 76909; 1 figured paratype, U.S.N.M. no. 76910; l unfigured paratype, U.S.N.M. no. 76911. Diltribution in Texas.-Navarro group, Nacat<>C?h sand: North edge of Corsicana (518, type loc.); vicinity of Corsicana (763); vicinity of Kaufman (761). Aaa. South African Mua., vol. 28, pt. 2, p. 217, pl. 25, .... 11-15, 1930. ANCHURA? PLENOCOSTA Stephenson, n.ap. Pl. 56, fig. 14 In size, form, and general appearance this species is much like Anchura? lobata Wade. The axial ribs are thicker and extend fully developed to the suture above on all the whorls except the ultimate. The body whorl is slightly constricted just below the suture, but a constriction is lacking on the other whorls. Approaching the expanded outer Iip the axials become definite! y shortened, the last 2 or 3 of them forming nearly round, rather prom­inent nodes. The surface of the bodv whorl is densely crowded with fine micr~­scopic spiral lines of irregular trend; these are much too fine to be shown in the illustration. The outer lip is incom­plete around the margins in the holotype, but, as more completely preserved in one of the paratypes, it appears to be es­sentially like that of A.? lobata. Dimensions of the incomplete holotype: Height 38+ mm., diameter exclusive of the expanded outer lip 16 mm., diameter including this lip 28 + mm. Types.-Holotype, U.S.N.M. no. 76912; 8 un:figured paratypes, U.S.N.M. no. 20988. Distribution in Texas.-Navarro group, Nacatoch sand: Near Kaufman, Kaufman County (761). ANCHURA? ELEGANS Stephenson, n.sp. Pl. 56, figs. 11-13 Shell small for the genus, thin, tur­reted; apical angle about 35 degrees; body whorl about half the total height of the shell. Whorls 5, broadly rounded on the sides, only slightly constricted below the suture. Suture closely ap­pressed, moderately impressed. Proto­conch smooth, trochoid, with 3 volutions, and with apical angle noticeably greater than that of the main spire. Axial ribs small, narrow, somewhat variable, num­bering 24 to 28 on the penultimate whorl; they become smaller and less numerous toward the apex, near which they fade out; on the body whorl the ribs become coarser, wider al!.art, and tend to become short, strong, and nodose as they approach the aperture. Back of the outer lip the The University of Texas Publication No. 4101 body whorl descends anteriorly in a long gentle slope, becoming constricted near the terminus; passing; around toward the aper­ture the body whorl becomes sharply con­stricted. The aperture is elongated with an angular anal notch behind, and a relatively short, straight, narrow, almost pointed canal in front. The outer lip is widely expanded very much as in A.? lobata with a sharp spur above and a dull one below; the outer margin shows a tendency to thicken though none of the specimens ap­pears to be mature; the inner lip is broadlv excavated, and forms a callus which ·spreads somewhat forward on the base and upward past the anal notch across the penultimate whorl to and be­yond the suture; this callus becomes thickened on the larger specimens. The whole outer surface, including the broad outer Iip, is densely crowded with fine microscopic threads, which are somewhat variable in strength on different individuals and on different parts of the same shell; this spiral sculpture is, however, more ~trongly developed than in Anchura? lobata media. Dimensions of the holotype, the proto­conch of which is partly broken away, and the anterior canal of which is incomplete: Height 21 + mm.; diameter, including expanded lip, 15 mm., excluding this lip 9 mm. This species is closely related to A.? lobaia Wade, but is much smaller and has much finer axial sculpture. A.? lobata media is intermediate in size and coarse­ness of axial sculpture beh\'een this species and A. lobata. The three forms mentioned and A. rostrata (Gabb) together form a compact subgroup. Types.-Holoty_pe, U.S.N.M. no. 76913; 1 figured paratype, U.S.N.M. no. 76914; 10 unfigured paratypes, U.S.N.M. no. 76915. Distribution in Texas.-Navarro group, Nacatoch sand: Vicinity of Corsicana ( 763, type loc.) ; 5 miles northeast of McClanahan (17371). ANCHURA? CIBOLOENSIS Stephenson, n.sp. Pl. 56, figs. 5, 6 Shell of moderate size, thin, turreted. Spire about half the total height of the shell; apical angle about 30 degrees. Whorls six. slightly convex to almost flat on the side~. Suture closely appressed, cfo.tincth hut narrowly impressed. Proto· conch simple, smooth, coiled three times, with apical angle corresponding to that of the main shell. The surface is unevenly ornamented and varies markedly on dif· ferent individuals; on the holotype the half of the body whorl nearest the aper· ture exhibits 3 to 6 widely spaced, low, dull axial ribs or folds which are strong· est just below the suture and fade out downward, separated by broad shallow interspaces; this whorl is slightly con· stricted below the suture. The penultimate whorl and apparently the anterior half of the antepenultimate whorl are smooth, flattish to very slightly convex, and slightly constricted below the suture; the posterior half of the antepenultimate whorl, and two or three whorls back of that present numerous low rather sharp axial ribs; these have an extremely variable strength of development on dif · ferent individuals and seem to be almost wanting in some. The aperture is elongated, with a distinct anal notch he· hind, and extends forward in a moderately long narrow, slightly sinuous canal. The inner Ii p is broadI y excavated and forms a thick callus extending somewhat for· ward on the base; on some specimens this callus extends upward about halfway across the penultimate whorl; the outer lip is broken away on all the numerous speci· mens from the type locality and is evi· dently thin and frail; the holotype, how· ever, and several other specimens show the beginning of an expanded Iip, and a dis· tinct reflection of the posterior margin of this lip onto the penultimate whorl. Dimensions of the holotype: Height about 31 mm., thickness exclusive of outer lip about 10 mm. This species is definitely distinct from previously described species. Types.-Holotype, U.S.N.M. no. 76916; 1 figured paratype, U.S.N.M. no. 76917; 20 selected paratypes, U.S.N.M. no. 76918. Distribution in Texas.-Navarro group, Kemp clay: West of Zuehl (7720; 7721, type lot). Invertebrate Fossils of the Navarro Group ANCHURA 7 L YNNENSIS Stephenson, n.ap. Pl. 56, figs. 16, 17 Shell of medium size, elongate-conical, apical angle not measurable, but the species appears to be more slender than any of the other Texas Navarro species. Whorls 5 +, broadly convex to flattish on the sides. The suture appears to be closely appressed and not deeply im­pressed. The suture is bordered below by a flattish posterior fasciole, 1/s to 1/i the total width of the whorl, and the lower edge of this fasciole is marked by a slightly impressed r e v o 1v i n g sulcus. Protoconch not preserved. The surf ace is ornamented with numerous, narrow, mod­erately prominent, nearly direct axial ribs which are much narrower than the inter­1paces and which in their trend exhibit a broad, very slight concavity toward the aperture; these ribs cross the posterior faeciole to the suture; the axials number about 19 on the penultimate whorl and 14 on the antepenultimate whorl. The periphery of the body whorl is broadly rounded and the anterior constriction is lees abrupt than on most species of the genus; the axials on the body whor 1 pass down over the periphery but die out quickly on the upper slope of the base. The molds exhibit obscure traces of fine revolving ridges which have been largely destroyed in the process of fossilization. The body whorl is poorly preserved, but the aperture is elongated, and the siphonal canal though not complete appears to be rather long; the inner lip forms a rather thick callus; the outer lip is not preserved. Dimensions of the incomplete holotype: Height SI+ mm., thickness approximately 15 mm. The species is distinguished from other Atlantic and Gulf Coastal Plain species chiefly by its proportionately more slender spire. Holotype.-V.S.N.M. no. 76919. Distribution in Texas.-Navarro group, Corsicana marl: 3 7 /10 miles southwest of Campbell (15547). ANCHURA? COOKI Stephenson, n.sp. Pl. 56, figs. 7-10 Shell of moderate size, turreted, apical angle about 28 degrees. Whorls 7 or 8, broadly convex on the sides. On the internal molds the suture is apparently not closely appressed, and on some of them the suture is bordered above by a rather thick, round-crested ridge representing a ridge of callus; this ridge marks the posterior margin of the inner lip, which left the ridge of callus behind it as it grew for­ward. This ridge was probably overlapped by the shell so that the suture was just back of the ridge instead of in front of it as it appears in the mold. Protoconch not preserved. With the exception of the forward part of the body whorl, and probably several small volutions near the apex, the shell is covered with subangular axial ribs which vary somewhat in form and spacing, but are in general narrower than the interspaces; these ribs number 10 to 14 on each of the larger whorls, and on any one individual tend to increase slightly in number from the body whorl backward toward the apex; the ribs trend downward and slightly forward, and are covered at their anterior ends by the ridge of callus, previously mentioned. On the half of the body whorl farthest back from the outer lip the axials pass down over the periphery and die out on the base; on the half nearest the outer lip they become more widely separated and pro· gressively shorter at the expense of their forward ends. Faint traces of fine spiral threads may be seen on one or two of the specimens and their apparent absence on most specimens may be due to their poor state of preservation. The aperture is elongated and passes posteriorly into an anal notch; anteriorly it passes into a rather short, pointed canal. The outer lip of adults is broad at the beginning of its expansion, but narrows abruptly into a long (10+ mm.), slightly descending projection, or wing, having a minimum width of about 2.5 mm. at the narrowest part preserved; this wing is incomplete on all the available specimens, none of which The University of Te.?.:as Pubrication No. 4101 show the upward projection at the extrl"m­ity, which presumably would be pr<:>sC'nt on perfect shells; the wing is tnl\'ersed longitudinally a little above the center by an obtusely rnbangular ridge which dies out posteriorly at the base of the wing~ on the lower margin of the wing about 4 mm. in front of the columella is a broadly rounded projection associated with a broad, shallow, inward plication. The inner lip is broadly excaYated. and forms a thick callus which spreads forward sev­eral millimeters on the base, and a little upward on the penultimate whorl, forming a ridge which, as previously stated, parallels the suture on all of the larger whorls. Dimensions of the cotype shown in plate 56, figure 10: Height about 34 mm., di­ameter exclusive of the wing about 12 mm. Individuals of the species are numerous at the type locality, the collection includ­ing 16 or more. The shell substance is not preserved, but the external and in­ternal molds reveal the features of the shell with a fair degree of accuracy. The specimens are all more or less distorted by mechanical pressure. The species appears to be distinct from anything heretofore described. Types.-Four cotypes figured, U.S.N.M. no. 76920; 14 unfigured cotypes, U.S.N.M. no. 76921. Named in honor of Mr. Carroll E. Cook of Austin, Texas, who assisted in finding the locality and in making the collection. Distribution in Texas.-Navarro group, Corsicana mar1: 2 3/ 5 miles north by east of Malta l5310, 12934, 16159); ?1/2 mile north of the town of Sulphur Bluff (5321) ; about 5 miles east by north of Greenville ( 12924, type loc.) ; ?3 7 / l 0 miles southwest of Campbell (15547); ?1-~-~ miles N. 20° \V. of Tona siding (15545) ; ?west of Kaufman (7548). ANCHURA CADDOENSIS Stephenson, n.sp. Pl. 56, figs. 3, 4 Shell small for the genus. Spiral angle about 38 degrees. 'Whorls 6, evenly rounded, approaching plumpness. Axials numerous and prominent, but irregular in strength and spacing, an occasional one forming a nonprominent varix; the axials numb~r 15 to 18 on each of the larger whorls; they decrease in size, but appar· ently not in number, on the successively smaller whorls toward the apex; in trend each axial is broadly concave toward the front and is a little oblique toward the front in its trend from above downward across the whorl. On the body whorl the axials fade out as they pass downward over the broadly rounded periphery onto the moderately constricted base. The surface is covered with fine closely spaced spiral ridges which override the axials. The aperture is elongated, ending posteriorly in an acute angle, and anteriorly in a narrow· straight channel which is incom· plete on all the available specimens. The outer lip expands and is projected above into a narrow upbent process, the maxi­mum incomplete observed length of which is about 5 mm.; running centrally along this process is a ridge which passes back· ward onto the body whorl where it fades out within a few millimeters; the upper margin of the process is thickened and this thickening continues along the upcurved margin of the outer lip to the point where it joins with the upper margin of the inner lip; the lower obliquely sloping margin of the outer lip presents two downfolds, separated by a broader upfold; the down· folds are coincident with two short pointed projections of the margin. The inner Ii p is broadIy excavated and spreads forward as a thin callus covering a band about 2 millimeters wide on the parietal wall in advance of the aperture. The columella as revealed in broken shells is twisted. Dimensions of the holotype: Height 18+ mm.; diameter including outer lip 11.6 mm., exclusive of outer lip about 7.8 mm. Anchura? johnsoni Stephenson353 is a closely related, somewhat larger species. Types.-Holotype, U.S.N.M. no. 76923; 1 figured paratype, U.S.N.M. no. 76924; 12 unfigured paratypes, U.S.N.M. no. 76925. 353Stephenson, L. W., ~orth Carolina Geol. and Econ. Survey, vol. 5, p. 370, pl. 92, figs. 1-4, 1923. Invertebrate Fossils of the Navarro Group Distribution in Texas.-Navarro group, Nacatoch sand: 14,i miles northeast of Quinlan ( 16162, type lot; 16171) ; vicin­ity of Kaufman (761). ANCHURA? CAMPBELL! Stephenson, n.sp. Pl. 56, figs. 1, 2 Shell of medium size. Apical angle 50 degrees, decreasing to 30 degrees on the large part of the spire. Whorls 6, each broadly rounded on the side. Protoconch smooth, forming a low spire with about 21h volutions. Axials numerous, closely spaced, rounded on the crest~, slightly curved in trend with the concavity toward the front; 24 axials on the penultimate whorl, decreasing to 15 or less on '!hor~s near the apex; an occasional axial is slightly enlarged to form a nonprominent varix. On the body whorl the axials be­come broader, more prominent, more widely spaced, hut weaken toward the aperture and practically fade out just back of the expanded outer Iip; these axials also weaken and fade out down­ward on the base a little below the broad! y rounded periphery. The whole surface is covered with fine, closely spaced, almost obscure threads. The a p e r t u r e is elongated, ending posteriorly in an acute angle, and becoming narrow anteriorIy; the siphonal channel is broken away in the available material. The outer lip expands into a spur-like process wh~ch bends slightly upward, hut the anterior portion is broken away; this lip bears a narrow subangular rib which doubtless continues out toward the tip of the process; the lower part of the outer lip is broken away; the upper part of this lip is moderately thick, and curves up­ward, joining the side of the whorl about 2 mm. above the suture. The inner lip is broadly excavated below and forms a thin callus spreading forward 2 or 3 mm. on the parietal wall. The columella is not well exposed. Dimensions of the incomplete holotype: Height 22+ mm.; greatest diameter, ex­clusive of the expanded lip, 10.5 mm. Compared with Anchura? caddoensis this species has a wider apical angle, is plumper, has finer and more numerous axials, and a proportionate! y larger outer lip. Types.-Holotype, U.S.N.M. no. 76926; 4 unfigured para types, U .S.N .M. no. 76927. Named for the Hon. Thomas M. Campbell, Governor of Texas, 1907-1911. Distribution in Texas.--Navarro group, Neylandville marl: Corsicana road 2% miles north of Corbet (16170, 17365; Tex. Bu. 17300, type lot). ANCHURA? HOGGI Stephenson, n.sp. Pl. 57, figs. 18-20 This species is based on two specimens, one adult and the other about half grown, both of which are incomplete at each end. Shell thick and of medium size with spiral angle of about 35 degrees. Whorls closely appressed, suture sharply but slightly im­pressed. Sides of whorls broadly rounded; on the whorls of the spire the greatest convexity is a little below the midheight. The body whorl is moderately plump and very broadly rounded on the periphery; the base slopes gently to the anterior canal. Axials numerous and gracefully sinuous on the body whorl where they number 23; they are round­crested, only moderately prominent, and die out well down toward the base. Spirals numerous, rather obscure, . oyer­riding the axials; they are more d1stmct on the base of the body whorl than else­where. Aperture lenticular with a nar­row anal canal at the rear, and passing into a well defined siphonal canal in front, only the upper end of which .is preserved in each specimen. Outer hp broken away. Inner lip broadly ex­cavated, forming a thick callus above just below the anal canal, becoming only thml y covered with callus on the lower part of the parietal wall. Columella smooth, slightly twisted. Dimensions of the holotype: Height 32+ mm., diameter 18+ mm. Types.--Holotype, U.S.N.M. no. 76928; 1 paratype, U.S.N.M. no. 76929. Named for the Hon. James S. Hogg, Governor of Texas, 1891-1895. Distribution in Texas.-Navarro group, Kemp clay: West of Zuehl (7721). The University of Te~ras Publication No. 4101 Unidentified specimens of the ANCHURA group Among the collections from the :\aYarro group are numerous poorl~· presern·d specimens which are referred to Anclwra, some of them questionably. Two immature specimens from the Ney­landville marl on the Corsicana road, 2~~ miles north of Corbet. Narnrro County ( 16170), han· the axial sculpture don;­inant~ as in most species of Anchura. but the whorls are rather strongly constricted below the suture and they may belong to another genus. U.S.N.M. no. 76930. Fragments of specifically indeterminate internal molds of large indiYiduals of Anchura were found in the Nacatoch sand at two localities as follows: In the Dallas road, 3/ 5 mile west of Kaufman, Kaufman County (7545, U.S.N.M. no. 76931) ; pub­lic road %, mile northeast of Chatfield, Navarro County (7572, U.S.N.M. no. 76932). Poorly preserved specimens of Anclzura from the Corsicana marl at one locality in Guadalupe County, and three localities in Bexar County, are similar to each other in form and sculpture, but their state of preservation is such that they cannot be satisfactorily compared and none of them is well enough preserved to serve as a type. They all appear to be different from any described species of Anchura, and some of them may not belong to this genus. The apical angle of these specimens ranges from 35 to 40 degrees. The body whorl is elongated, and the periphery broadly rounded. Axials are numerous but are not well presen·ed on some specimens; on the body whorl the axials sweep well down 0ver the base in broadIy sinuous curves; the revoking sculpture is not well pre­served on most specimens but on some ap­pears as relati,·ely fine, numerous, closely spaced, flattish ridges, broader than the interspaces, and overriding the axials. Dimensions of an incomplete but only slightly deformed specimen '· 15520, pl. 57, fig. 16) : Height 35 + mm., diameter 17 mm. One other specimen (1552-l) is shown in plate 57~ figure 21. The locali­ties are as follows: Cut in San Antonio road~ 6 miles east of Castro\·ille in Bexar County (15502, U.S.N.M. no. 76933); pit of Standard Fuller's Earth Company, % mile north of the Castroville road, 14 rniles wt"st of San Antonio, Bexar County l 15520. lr.S.N.M. no. 76934.); abandoned earth tank north of the Castroville road, ] 1, ~~ miles wl"'st of the crossing of Leon Creek. Bexar Countv (15522, U.S.N.M. no. 76935) : westward-facing bluff of Guada­lupe River valley 1 3/10 miles north of l\kQueeney, Guadalupe County (7637, U.S.N.M. no. 76936; 15524·, U.S.N.M. no. 76937). A specimen (pl. 57, fig. 17) found in the Corsicana marl, in a cut of the San Antonio road, 6 miles east of Castroville ( 15502), in Bexar County, is a moderately large internal mold, including 3 rapidly enlarging whorls on which the external sculpture has been rather weakly im· pressed. The apical angle is 35 or 36 degrees; the whorls are broadly convex, becoming flattish to slight!y excavated above, and the suture is moderately im­pressed; the sculpture consists of rather evenly spaced subangular axials num· bering 23 to 25 on each of the three largest whorls; the revolving ridges are rather '"-eakly developed but on the penultimate whorI consist of 7 or 8 primaries with Yery dimly preserved fine intermediate threads; the periphery is rounded, and the base rounds down rather abruptly to the columella. Dimensions of the incomplete specimen are: Height 41+ mm., di· ameter about 23 mm.; the maximum diameter has been increased somewhat by lateral pressure. U.S.N.M. no. 76938. Another adult specimen from the same locality (16156) has 3 of the larger whorls rather poorly preserved. U.S.N.M. no. 76940. A similar incomplete specimen from the Corsicana marl was found in a pit of the Standard Fuller's Earth Company, 4h mile north of the Castroville road, 14 miles 'vest of San Antonio (15520). This specimen includes nearly 5 whorls, and its dimensions are: Height 39+ mm., diameter 21 mm. It may belong to the same species as the preceding specimen. C.S.N.M. no. 76939. In the Corsicana marl are specifically indeterminate molds and prints of speci­mens referred, in part questionably, to Invertebrate Fossils of the Navarro Group Anchura as follows: Branch east of road 21h miles north of Tona siding, 5 miles southwest of Quinlan, Hunt County (15546, U.S.N.M. no. 76941) ; road ditch, 14;5 miles N. 20° W. of Tona siding, in Hunt County (15545, U.S.N.M. no. 76942); road ditch in westward-facing slope of Lynne Creek valley, 3 7 /10 miles southwest of Campbell, Hunt County (15547, U.S.N.M. no. 76943); Dallas road at west edge of Kaufman, Kaufman County (7548, U.S.N.M. no. 76944); ditch in Cameron-Buckholtz road, %, mile west of Pettibone station, Milam County (14131, U.S.N.M. no. 76945); 2 miles south-southeast of Marion, Guadalupe County (13389, U.S.N.M. no. 76946). The pathologic specimen shown in plate 57, figure 22, from the Corsicana marl in a westward-facing bluff on Guadalupe River, 1 3/10 miles north of McQueeney, Guadalupe County ( 15524), probably be­longs to Anchura, and is an undescribed species, but it is not satisfactory as a type specimen. U.S.N.M. no. 76947. The Kemp clay has yielded numerous internal and external molds of an unde­scribed species of Anchura? from a wash in a field 3 miles southea-5t of Manor, Travis County (16141). The form, as shown by the internal molds, is much like that of A. ciboloensis, but is less slender, the spiral angle being about 40 degrees. The external molds are imperfect, but many of them show fine axial ribbing on the smaller whorls toward the apex; an­teriorly these axials fade out and are practically wanting on the body whorl, which is nearly smooth; the axials ex­tend from the suture down and a little forward and in trend are broadly concave toward the front; the species differs from ciboloensis in the absence of axial folds on the body whorl. The outer lip is not preserved in any of the material, though the initial expansion of the lip appears on the adult internal mold of one speci­men. Dimensions of this incomplete mold: Height 22+ mm., diameter, exclu­sive of the outer Ii p, 11 mm. U .S.N .M. no. 76948. One internal mold with the axial ribs imperfectly impressed upon it, from the Kemp clay near Deatsville, 2 miles north­west of Webberville, Travis County ( 764), resembles A.? cooki in the character of the axial ribs, but the spire is not so slender and the lip is wanting. U.S.N.M. no. 76949. An incomplete shell in another collec­tion from the same locality (14125), questionably referred to Anchura, exhibits numerous, rather long axial ribs on a plumply rounded body whorl; on the base below the ends of the axials are 7 or 8 spiral ribs of medium fineness. The diameter is about 9 mm. U .S.N .M. no. 76950. Another shell from the preceding col­lection (14125), probably an Anchura, includes part of the body whorl and the penultimate whorl; it is not so plump as the preceding shell, and is distinctly flat­tened on the upper part of the body whorl; the axial ribs are numerous and die out high on the basal slope; the shell is covered with very fine spiral ribs which are distinct on the basal slope and very obscure over the rest of the shell. U.S.N.M. no. 76951. A small tip of an Anchura? spire was found in the Kemp clay at a depth of 730 feet in a well of the Robinson Oil & Gas Company, Cargile No. 1, 2 miles west of Groesbeck, Limestone County (13132). The fragment shows a smooth protoconch and fine axial ribbing on the two earliest whorls of the spire. U.S.N.M. no. 76952. Genus DREPANOCHILUS Meek Type species.-Rostellaria americana Evans and Shumard,3 54 preoccupied; renamed Arroges ( Drepanochilus) evansi Coss­mann.355 According to Meek356 this group is char­acterized as follows: "Shell with outer lip terminating in a single backwardly curved, scythe-shaped, pointed process; beak short." To this should be added: A spirally striated, flattish to gently con­vex, strongly constricted base with a 354 Evans, John, and Shumard, B. F ., Acad. Sci. St. Louis Trans., vol. 1, p. 42, 1857. 3"5Cossmann, M., Essais Paleoc. Comp. 6th Liv., p. 75, 1904. 350Metk, F. B., Rept. U.S. Gcol. Survey Terr., vol. 9, p. 324, 18i6. The Univers-ity of Texas Publication No. 4101 strong peripheral lira on the body whorl; anteriorly this lira continues out onto the spur-shaped prolongation of the lip as a pronounced, narrow ridge, and apically it dies out on or before reaching the penultimate whorl; below the periphery on the base may be ] , 2, or 3 primary lirae and numerous small secondary Iirae. DREPANOCHILUS TEXANUS Stephenson, n.sp. Pl. 57, fi~~-1-4 Shell small for the group. Spire conical with apical anale of about /15 degrees. Whorls 5, mode~ately convex on the sides, with no constriction below the suture. Suture closely appressed, deeply im­pressed. Protoconch not preserved on the available material. The surface is orna­mented with numerous rather closely spaced, axial ribs which vary somewhat in prominence and in the sharpness of their crests; in general these ribs are about equal in width to the interspaces; they trend downward and slightly forward, and the trend is broadly concave toward the aperture. The ribs number 33 on the body whorl, 28 on the penultimate, and 24 on the antepenultimate whorl of the holotype. The axials on the body whorl terminate below against a moderately strong, ob­scurely noded spiral rib which occupies the periphery of this volution; and dies out apically before reaching the penulti­mate whorl; a second similar but less prominent spiral parallels the first one about 1.5 mm. farther forward on the base. The periphery of the body whorl is ob­tusely subangular, and the base rounds down abruptly to the columella. The whole surface is covered with fine spiral threads which override the axials; on the base these threads are stronger than else­where and tend to alternate in size. The aperture is imperfect in the available material, but is elongated, passes back­ward into an angular anal canal, and forward into an anterior narrow canal, which is broken away in all the specimens. The outer lip is mostly broken away on all the shells, but at the posterior margin in adults it is reflected outward and also upward about one-third of the way across the penultimate whorl. The inner lip forms a rather thick callus which is broadly excavated, spreads noticeably forward over the base, and folds neatly forward over the columella in front. Dimensions of the incomplete holotype: lfoight 17.5+ mm., diameter 9.~ mm. (exclusive of the expanded outer hp). The material includes eight incompletely preserved shells from the .typ~ locality, on all of which the outer hp is largely or completely broken away. Th~ species i~ closely allied to Drepanochilus evansi Cossn~ann from the Fox Hills sandstone and the upper part of the Pierre shale of the Upper Cretaceous of the Western In· terior, but it is not so slender and the axial ornamentation is somewhat coarser and is more strongly developed on the posterior part of the body whorl. Types.-Holotype, U.S.N.M. no. 76953; 1 figured paratype, U.S.N.M. no. 76954; 6 unfigured paratypes, U.S.N.M. no. 76955. Distribution in Texas.-Navarro group, Kemp clay: 3 miles 'S. 30° W. of Thrall (15537, type lot; 17370). DREPANOCHILUS? MARTINI Stephenson, n.sp. Pl. 57, fig. 5 Shell of medium size, turreted, apical angle 28 degrees. Five whorls can be counted on the incomplete holotype; they are broadly and regularly rounded on the side. Suture closely appressed, moderately impressed. Protoconch and an undeter­mined anterior part of the holotype broken away. The surface is characterized by numerous narrow, moderately prominent, somewhat irregularly spaced axials, nar· rower than the interspaces, which sweep downward and a little forward across the whorl in a broad curve concave toward the aperture; on the largest whorl preserved on the holotype these axials number 23; on three successive! y smaller whorls back toward the apex the axials number respec· tivel y 26, 30, and 32, thus showing an in­crease in number in that direction. The axials are crossed by 8 primary, narrow, revolving ridges which are a little more widely spaced on the posterior than on the anterior half of the whorl; three seconda· ries occupy each of the interspaces, and on the larger whorls tertiaries appear ~e· tween the other ridges where the spacmg between the primaries is widest; all of the revolving ridges override the axial~; under the microscope the numerous axials and Invertebrate Fossils of the Navar.ro Group the densely crowded spirals produce an elegant sculptural pattern. The periphery as shown by the paratype is obtusely suh· angular and weakly carinated, and the base descends abruptly to the columella; the axials on the body whorl end abruptly at the periphery; the base is at least partl v if not wholly covered with narrow, closely spaced revolving ridges; there is a narrow spiral furrow just in front of the periph­ eral carina. These features suggest generic relationship with Drepanochilus. Dimensions of the incomplete holotype: Height 26+ mm., diameter 13+ mm. The dimensions of the one incomplete paratype, which may not he an adult, are : Height 23+ mm., diameter 13 mm. The axial ribs on this species are more numerous than on any Coastal Plain 1pecies heretofore described; the orna­ mentation is in this respect comparable to that of the type species, Drepanochilus eot11Ui Cossmann, from the Fox Hills sand­ stone (Upper Cretaceous) of the Western Interior. Compared with Drepanochilus? davisi, this species is less slender, has more numer­ ous axials and spirals, and a less deeply impressed suture. Type1.-Holotype, U.S.N.M. no. 76956; 1 unfigured paratype, U.S.N.M. no. 76957. Named for Capt. Herman Martin, who led an expedition (entrada) to the Tejas tribe of Indians in 1650. Di&tribution in Texas.-Navarro group, Nacatoch sand: Vicinity of Chatfield ( 762, trpe loc.) ; 2% miles north of Corsicana (14114), 2% miles west by south of Corsi­ cana (17368). DREPANOCHILUS? DAVISI Stephenson, n.sp. PI. 57, figs. 13, 14 Shell of moderate size, turreted, apical angle about 25 degrees. Whorls 8 in the incomplete holotype, broadly convex on the sides. Suture closely a ppressed, moderately impressed. Protoconch not preserved. The 4 larger whorls of the holotype are ornamented with moderately prominent axial ribs whose trend describes a curve broadly concave toward the aper­ture; the ribs number about 20 on the largest whorl, are round-crested and are much narrower than the interspaces. The shell is further ornamented with numerous . spiral ridges which override the axials and which consist of 8 relatively strong pri­maries, and 2 or 3 much smaller, some­what uneven secondaries between each of the primaries. The sculpture is not well preserved on several of the smaller whorls at and near the apex. One incomplete fragment of a body whorl shows the axial ribs ending at the periphery which is sharply rounded; on the abruptly con­stricted base are 4 or 5 major, broadly rounded spiral ridges, the two outer ones of which are the largest and the three inner ones of which become progressively smaller toward the columella; both the ribs and interspaces are covered with num­erous, somewhat uneven spiral threads. The outer Iip and anterior canal are broken away; the inner lip is broadly excavated and forms a thin callus on the base. Dimensions of the incomplete holotype: Height 24+ mm., diameter 9 mm. The paratype, an incomplete body whorl, has a diameter of 14.5 mm. The species is placed questionably in the genus Drepanochilus because of the two largest major ribs on the base. The shell is more slender and the sculpture is coarser than are the corresponding features of D. evansi Cossmann, the type species of the subgenus. Compared with D.? martini, the shell is more slender, the suture more deeply impressed, and the sculpture coarser. Types.-Holotype, U.S.N.M. no. 76958; 1 unfigured paratype, U.S.N.M. no. 76959. Named for the Hon. Edmund J. Davis, Governor of Texas, 1870-1874. Distribution in Texas.-Navarro group, N acatoch sand: Vicinity of Corsicana ( 763, type loc.) ; 3/5 to 4/5 mile northeast of Chatfield ( 75 72) . DREPANOCHILUS? CORBETENSIS Stephenson, n.sp. Pl. 57, figs. 6-8 Shell small. Spiral angle about 32 de­grees. Whorls 6 or 7, sides evenly rounded and of only moderate plumpness. Proto· conch small, trochoid. Axials numerous, prominent, irregular in strength and spac­ing, hut in general narrower than the interspaces; varices widely and irregularly spaced, averaging about two to the whorl; on some specimens there is a tendency for the varices to occur, one below, or nearly below the other, or they may drop hack The Uniz-ersity of Te.ras Publication No. 4101 a little from whorl to whorl. The axials number 20 or 21 on the body whorl and decrease gra smalh•r whorls n~ar the apex: they are son1C'what irregular in their trend. but i·1 general are nearlv direct. with a ,-en· broad curye concave to~rard the aperture:. on the body whorl the axials end against a mod­ erat~ly prominent. rovnd-t~pped carina which marks the obtusely angular periph­ ery. The spiral ornamentation rnnsists of ,-ery fine ridges much narrower than the interspaces, and numbering 15 or more on the larger whorls: these o\·erride the axials and produce tinv tubercles on their crests: still finer secondaries begin to appear be­ tween the primaries on the larger whorls. The base is flattened and strongIy con­ stricted, curving rather sharply below into the columella: the base is ornamented with 10 or 12 narrow. low. smooth. relativelv widely spaced spirals: betwee~ some o.f which are still smaller secondaries. Aperture subovate. angul~r posteriorly, and passing anteriorly into a narrow strai~ht. beak-like canal of moderate length. The three available specimens are apparently immature and gfre no clue as to the character of the outer lip. Dimensions of the holotype: Height l l.5+ mm., diameter 5 mm. Although the character of the outer lip is not known. the carinated periphery and flattened base seem to ally these species with Dreparzochilus lVleek. Types.-Holotype, U.S.~.\L no. 76960; 1 figured paratype, U.S.N.l\L no. 76961; 1 unfigured paratype, C.S.N.M. no. 76962. _Distrib~1tion in Texas.-:\avarro group. \eylandnlle marl: 21 ~ miles north of Corbet 116170. type lot: 1 7365 '1. DREPANOCHILUS TRILIRATUS Stephenson, n.sp. PI. 57, figs. 9. 10 Shell sn~all. turreted. with spiral angle of 32°. "horls about 6. regularly conYex ?n the sides. Suture compressed~ deeply unpressed. Protoconch broken awav. Bo?r whorl inflated above, sharply co;1­st~·1cted on the base: periphery marked w1t!1 a ~rominent. narrow primary spiral which nses a little as it approaches the broken outer lip: below on the base are 2 successi,·ely weaker, widely spaced spirals; the lower of the two interspaces bears 2 weak secondaries, the upper one the weaker: the rest of the base below and the anterior extension are covered with about a dozen closely spaced fairly regular, small ribs which become succ~ssively some. what weaker from above downward. Abow the peripheral ridge the body whorl is ornamented with 19 narrow axials which are broadlv concave in trend toward the aperture. a~d are much narrower than the interspaces. About a dozen fine, fairly regular. spiral threads override the axials; the axials override the peripheral ridge, producing nodes thereon, but die out in the first interspace below, some of them reach· ing the next spiral below. The peripheral ridge becomes weaker posteriorly and fades out on the penultimate whorl, and on the whorls of the spire the axials extend to the second basal spiral which forms the bot· tom of the sutural depression. The axials number 16 on the penultimate whorl and about the same number on the antepenul· timate whorl; occasional, irregularly spaced axials are enlarged to form varices. The expanded outer lip is badly broken away, but the aperture is lanceolate, with an acute posterior angle, and converges to a short narrow canal in front. The colu· mella is slender, smooth and straight. Dimensions of the incomplete holotype: Height 17+ mm., diameter 7.5+ mm. The species is closely allied to Drepano­chilus qua.drilfratus (Wade),357 but has 3 instead of 4 primary spirals on the base and has fewer axials on the whorls. Holotype.-U.S.N.M. no. 76963. Distribution in Texa.s.-Navarro group, Neylandville marl: Corsicana road 2% miles north of Corbet (17365). l\"avarro group, Nacatoch sand: State Highway 22, 2~,'2 miles west of the court· house at Corsicana (17368, type loc.). Unidentified specimens of DREPANOCHILUS Two specimens of Drepa.noclzilus from the Neylandville marl on the Corsicana road, i~~ miles north of Corbet (16170, U .S.N .M. no. 7696-1-, pl. 57, figs. 11, 12; 17365, U.S.N.M. no. 76965) are closely analogous to Drepa.nochilus triliratus. The figured specimen includes parts of the body whorl and of the penultimate whorl and 857Wad<', Bruce, U. S. Geol. Survey Prof. Paper 137, p. 151, pl. 53, figs. 3, 4, 1926. Invertebrate Fossils of the Navarro Group appears to be an adult with the outer lip broken away. The axials are numerous and strong and are overriden by fine spirals; an occasional axial is swoll~n to the form of a varix. On the penultimate whorl, approaching the body whorl, obscure nodes begin to appear on suc­cessive axials a little above the suture; passing forward these nodes grow in strength and gradually become connected with each other by an intercostal spiral ridge which in turn increases in strength and on the body whorl becomes a prom­inent noded peripheral carina; on a com­plete shell this carina would be seen to pass forward onto an expanded spur-like labrum like that possessed by Drepano­chilus quadriliratus (Wade).358 On the base below the peripheral carin a are two spiral lirae and in addition the base is covered with numerous fine, spiral ridges. The anterior canal is broken away, but ap­ pears to he of the short, narrow beak-like type. This form has a shorter spire and more numerous axials than has D. trilira­tus. Three immature specimens of Drepano­chilus, from the Ney land ville marl, on the Corsicana road, 21;2 miles due north of Corbet, Navarro County (16170), resem­ble D. ?corbetensis from the same locality, but they are less slender and the proto­conch is larger and has a wider apical angle. They seem to represent a different species, but this can not be certain Iy as­certained without a larger suite of speci­mens for comparison. U.S.N.M. no. 76966. A nearly complete whorl (pl. 57, fig. 15) from the same locality ( 16170), hav­ing a diameter of 8 mm., is similar in sculpture and in the character of its periphery and base, to D.? martini, but the sculpture is a little coarser. The specimen is inadequate for determination. U.S.N.M. no. 76967. Another specimen from the same locality (16170) has a maximum diameter of 5.5 mm., and includes about two and a half whorls. Its sculpture is similar to that of D.? martini, but is finer, and it appears to be more slender in form; it is probably a distinct species. U.S.N.M. no. 76968. -Wade, Bruce, U. S. Geol. Survey Prof. Paper 137, p. 151, pl. 53, 611. 3, 4, 1926. Genus PTEROCERELLA Meek Type species.-Harpago tippana Conrad. Pterocerella Meek359 is a good genus in its own right, and need not be linked with the living Cheno pus Philippi as a sub­genus, as was done by Cossmann. 360 It is certain I y generically distinct from the Jurassic Phyllochilus Gabb (1868). PTEROCERELLA POINSETTIFORMIS Stephenson, n.sp. Pl. 58, figs. 9-12 1907. Pterocerella tippana (Conrad). Weller, Geol. Survey New Jersey, Paleontology, vol. 4, p. 718 (in part), pl. 83, fig. I (not fig. 2). Shell of moderate size, thin, conical, apical angle 54 degrees. Protoconch small, trochoid, smooth, dextral, coiled about 3 times, and rather sharply dis­tinguishable from the first whorl of the conch. The whorls are 6 in number on adults, are moderately convex on the sides, and have no axial ornamentation. Suture closely appressed, moderately impressed. A narrow, prominent sharply round­crested revolving carina traverses each whorl a little below the middle, and ex­tends back to the junction of the conch with the protoconch. A similar narrow carina, a little less prominent, marks the periphery of the body whorl; this carina is not quite overridden by the posterior margin of the growing conch, so that its crest appears as a narrow, sharply defined band just above the suture. The base is abruptly constricted, and is smooth with the exception of 2 gentle revolving swells which divide the base into 3 bands of nearly equal width. The outer lip is fan­tastically expanded and subdivided into a series of 6 long, widely flaring, paddle­like wings of more or less irregular out­line, separated by deep, wide indentations. The two carinae on the body whorl and the two revolving swells on the base pass forward onto the outer lip, following respectively the centers of the 4 inner wings, on which they all appear as sharp, narrow, prominent carinae; the two outer 359Meck, F. B., Check list of the invertebrate fossils of North America, Cretaceous and Jurassic: Smithsonian Misc. Coll., vol. 7, no. 177, p. 36, 1864. 300Cossmann, M., Essais Paleo. Comp., 6th Liv., p. 70, 1904. The University of Texas Publication No. 4101 wings, that is the posterior and anterior of the 6 wings, are also marked centraily by similar carinae; these 2 outer wings appear as having forked off from the nearc~l. adjacent wings. The under side of each wing is cut longitudinally by a channel which opposes the carina on the outside of the wing, and this channel is closely bordered on each side by a narrow prom­inent carina; these channels connect with the aperture, which is somewhat elongated though fairly wide open. The inner lip of adults is thick and stands out prominently away from the base of the shell. Dimensions of the holotype: Height, disregarding the downward expansion of the wings, 34 mm.; diameter measured to the base of the wings, about 22 mm. The maximum wing spread is 70 mm. or more. This species exhibits the most fantas:ic wing expansion of any known gastropod species in the Upper Cretaceous of the Atlantic and Gulf Coastal Plain. Weller figured the holotype of this species as an example of P. tip pana (Con­rad). The type of the latter is lost, but on typical specimens from the Ow1 Creek formation, on Ow1 Creek, 21/2 miles north­east of Ripley, Mississippi, in the National Museum collection, the whorls of the spire are smooth, or have only a weakly devel­oped revolving carina, the spire is more slender and the wings are less widely separated; these differences are sufficiently marked to justify specific separation. The specimens from the Coon Creek tongue of the Ripley formation, at Coon Creek, Tenneseee. which Wade361 referred to P. tippana (Conrad), resemble the Texas species, in that the whorls of the spire bear a prominent, narrow carina. but the spire is markedly more slender and the wings are less widely separated; the pres­ ence of the carina and other differences warrant the recognition of the Coon Creek shells as belonging to a species distinct from P. tippana. The internal mold from the Wenonah sand, New Jersey, which Weller referred to P. tip pana (Conrad), is too incom­pletely preserved to warrant its reference to any species. 3UIWadc, Bruce, L'. S. Geo!. Survey Prof. Paper 137, p. 152, pl. 53, fig~. 6, 7, 1926. One specimen in the National Museum (no. 205~-W) , from a locality 2% miles south of Dumas, Tippah County, Missis· ~ippi, though not completely preserved, is essentially like P. poinsettifonnis, and the stratigraphic position of this locality, as interpreted, is approximately the same as that of the Nacatoch sand of Texas. Types.-Holotype, U.S.N.M. no. 76969; 1 paratype, U.S.N.M. no. 20994; 1 para· type, U.S.N.M. no. 21061; 1 paratype, U. S.N.M. no. 76970. Distribution in Texas.-Navarro group, Nacatoch sand: Vicinity of Kaufman ( 761, type loc.) ; field 3/5 mile west of Kaufman (14103) ; vicinity of Chatfield ( 762, 1 figured paratype) ; Hervey Lake road, 2 1/10 miles northeast of Chatfield (Tex. Bur. 17302, 1 figured paratype). Outside distribution.-Mississippi at one locality in the Ripley formation, near Dumas, Tippah County (709). Family STROMBIDAE Genus PUGNELLUS Conrad PUGNELLUS DENSATUS NACATOCHANUS Stephenson, n.var. Pl. 58, figs. 5-8 1901. Pregnellus [sic] densatus Conrad. Hill, U. S. Geol. Survey 21st Ann Rept., pt. 7, pl. 48 ( p. 342), fig. 2. (Figure only.) 1906. Pugnellus densatus Conrad. Veatch, U.S. Geol. Survey Prof. Paper 46, pl. 10, fig. 3. (Figure only.) 1924. Pugnellus dcnsatu.s Conrad. Deussen, U.S. Geol. Survey Prof. Paper 126, pl. 11, fig. 1. (Figure only.) Shell of adult large, thick, and com· pletely covered with callus; outline and form very irregular due to the uneven dis· tribution of heavy deposits of callus, and to the thick expanded outer lip; on the prominently ribbed portion of the body whorl the covering of callus is thin. The stage of growth just preceding that in which the shell begins to take on its old age characters is without a covering of callus and presents a plump, smooth conch of about 5 whorls, the spire of which is shorter than the body whorl; the apical angle is about 67 degrees. The protoconch is a small, simple, dextral, slightly tilted shell having about two volutions. Suture closely appressed, not deeply impressed, bordered by a very narrow, flat, regular Invertebrate Fossils of the Navarro Group shoulder. The whorls are very broadly and even I y convex, and the growth lines extend from the shoulder obliquely down­ward and forward in a broad curve con· cave toward the aperture. At this stage the periphery of the body whorl is broadly and evenly rounded; at an earlier stage it presents a broad, suhobtuse angle; the base slopes off rather gently, becoming more sharp I y constricted toward the columella, and the growth lines become markedly sinuous as they cross from the periphery down over the base. The sur­face is apparently smooth hut under a lens exhibits fine, more or less obscure revolving lines or ridges which number 14 or 15 from suture to suture; lines of this kind can hare I y he detected on the base of some specimens. The aperture is elongated, acutely angular posteriorly and channelled anteriorly; the outer Ii p is thin and simple. The shell at this stage is about 40 mm. high (estimated) and 20 mm. in diameter. As the shell advances to maturity coarse axial folds or ribs begin to form on the upper half of the body whorl and at the stage where the outer Ii p begins to thicken these ribs number 8 or 9 and are present on the most mature half of the body whorl; they reflect the sinuosity of the growth lines and at the periphery are noticeably swollen into elongated nodes; they die out on the slope below. The last stage in the growth of the animal is marked by a backward reflection of the mantle from the aperture over the outer surf ace of the shell, and an excessive secre­tion of callus which enormously thickens the expanded outer lip, and also the inner lip which forms a broad, heavy, elongated mass extending from well down on the base, upward to and more or less com­pletely enveloping the tip of the spire; eventually callus is deposited over the entire shell, even covering though not ob­scuring the axial ribs. The outer Iip is expanded both downward and upward into dull, heavy projections, the latter the more prominent; these projections are set off from the main lip margin by distinct notches; on the inner surface of the outer lip a thick, moderately prominent ridge of callus parallels the outer margin, from which it is separated by a space of 7 or 8 mm. At this adult stage the anal canal occupies a posterior, broad round-bot­tomed channel, and anteriorly there is a well developed, slight! y sinuous si phonal canal of only moderate length. At the final stage of growth the aperture is greatly elongated, with the sides nearly parallel and only 5 to 7 mm. apart. Dimensions of the holotype: Height 44.5 mm.; greatest diameter, including the expanded lip, 44 mm.; diameter, not in­cluding the expanded lip, 27 mm. Compared with Pugnellus densatus Conrad, from the upper part of the Ripley formation at Owl Creek, Tippah County, Mississippi,362 this variety averages larger and is more massive, has coarser and a little more widely separated ribs, and the ribs are less sharply noded on the peripheral angle. The example of Pugnellus densatus Conrad, figured by Hill (see synonymy) was obviously this variety and probably came from either Navarro County or Kauf­man County, but its exact locality is not recorded, and the specimen is apparently lost. Hill's figure was repeated by Veatch and Deussen (see synoynmy). Pugnellus pauciplicatus Stephenson from the Snow Hill member of the Black Creek formation, North Carolina,363 is a nearly related species with, however, fewer plications on the body whorl. The specimen from Coon Creek, Ten­nessee referred by ~rade3M to Pugnellus densatus Conrad, has ribs similar to Con­rad's species except that they lack the peripheral nodes. It begins to assume old age characters at a much younger stage than either the Owl Creek species or the Texas variety, and should probably be treated as a separate variety. Types.-Holotype, U.S.N.M. no. 76971; 1 figured paratype, U .S.N .M. no. 76973; 1 figured paratype, U.S.N.M. no. 76974; 7 unfigured paratypes, U.S.N.M. no. 76972. 302Conrad, T. A., Acad. Nat. Sci. Philadelphia four., 2J ser., vol. 3, p. 330, pl. 35, fig. M, 1858. 363Stephenson, L. W., North Carolina Geo!. and Econ. Survey, vol. 5, p. 373, pl. 92, figs. 10-12, 1923. 3<14Wadc, Bruce, U. S. Geo). Survey Prof. Paper 137, p. 148, pl. 52, figs. 4, 5, 1926. The Unirersity of Te.ras Publication No. 4101 Distribution in Texas.---1\avarro p;roup, :\acatoch sand: Vicinity of Chatfield l 762~ loc. of holotype a.nd 7 unfip:urf'd paratypes) : north edge of Corsicana. l.;1 ~ H, loc. of 2 unfigured paratypes) ; nnmty of Corsicana (763) : 2~,~ miles north of Corsicana t 1-H l..t) : Yicinitv of Kaufman l 761) ; vicinity of Terrell (12246). PUGNELLUS ROBUSTUS Stephenson, n.sp. Pl. 58. figs. 1-1 Shell of adult large, thick, robust, ir­rerrular larrre}y cov~red with callus of t:' " t:' • uneven thickness; on the outer surface of the bodv whorl back of the thickened outer lip the covering of callus is thin, and on different individuals is more or less completely scaled off. The stage of growth just preceding that in which old age characters begin to form is a smooth, µlump shell similar to, though consider­ably larger than, that of Pugnellus densatus nacatoclwna. The apical angle i" about 65 degrees. There is a flat nar­row shoulder just below the suture; the "ide of the whorl is verY broadly rounded, lmt is modified abov~ just below the shoulder by a shallow excavated band about one-f~urth the width of the whorl. The growth lines extend first nearly ver­ticall;-downward from the suture and then . curve strongly forward becoming ~lighth· sinuous as they approach the suture. below; on the body whorl the rrrowth lines are markedlv si~uous as thev ~ . . pass downward owr the broadly rounded periphery and the base below. The sur­f ace is nearIy smooth except that on some specimens 4 or 5 faint re\·oh-ing lines appear on the penultimate whorl between the excarnted band and the suture below. On mature shells 4 or 5 obscure, but coarse. rather widely spaced longitudinal ribs are present on the upper part of the body whorl back of the aperture; these ribs are sinuous, following the trend of the growth lines. The uncallused surface of this part of the body whorl also shows a dozen or more wry faint, fine spiral Iines di,·erging from the convex part of the whorl toward the margins of the lip; apparently new lines are intercalated as the interspaces widen. The aperture of the adult is elongated, "·ith almost paralh·l sides about 10 mm. apart in the upper three-f.ourths of its l<·n~th: thP anal channel is broad and wide opPn with a broadly rounded bottom; the si phonal channel is of moderate len rrth and nearlv straight. The outer lip is ~-erY thick ai~d widely expanded; its upper," outer extremity is formed by a hea\'Y. blunt node which projects upward 1 O n~m. or more, but which is incompletely preser\'ed in the available material; on the maro-in a little more than halfway he· r. tween this large node and the anterior extremity of the shell is another curious, smaller, but prominent, blunt node which projects 6 or 7 mm. forward, a little downward and a little inward; this node is elonrrated in the direction of the margin, has ~ length of about 8 mm., and a thick· ness of 4 or 5 mm. The base just in front of the aperture is made plump by a de­posit of callus which spreads away from the aperture in a progressively thinning sheet, and the spire is completely callused oYer in such a manner as to present a twisted appearance. Dimensions of the holotype: Height 68 mm.; diameter, not including the ex· panded lip 32 mm.; diameter, including the expanded Ii p, 55 mm. This species is not apt to be confused with any other North American species of Pugnellus. Types.-Holotype, U.S.N.M. no. 76975; 1 figured paratype, U.S.N.M. no. 76976; 1 figured paratype, U.S.N.M. no. 76977; 9 unfigured paratypes, U .S.N .M. no. 20995. Distribution in Texas.-Navarro group, 1\acatoch sand: Vicinity of Kaufman ( 761, holotype and 9 unfigured para· types) ; field 2 miles southwest of Kauf· man (7547, 1 figured paratype); road 2 miles southwest of Kaufman (7546, 1 figured paratype). Unidentified specimens of PUGNELLUS Internal molds of Pugnellus having the general form of the younger stages of P. densatus Conrad, though a little more slender, have been collected from the Cor· sicana marl of the Navarro group at the following localities: Public road, VA Invertebrate Fossils of the Navarro Group miles south by east of Oak Grove, Bowie County (16160, U.S.N.M. no. 76978); road ditch westward-facing slope of Lynne Creek vallev, 3 7/10 miles southwest of Campbell, Hunt County (15547, U.S.N.M. no. 76979) ; the E. R. Ridley 30-acre tract, northwest corner of W. G. Lee Survey, about 3 miles southwest of Campbell (12927, U.S.N.M. no. 76980); Dallas road at west edge of Kaufman, Kaufman County (7548, U.S.N.M. no. 76931); pit of Standard Fuller's Earth Company, 4;5 mile north of Castroville road, 14 miles west of San Antonio, Bexar County (15520, U.S.N.M. no. 76982). The Kemp clay has yielded one imper­fect mold of the body whorl of an inde­terminate Pugnellus, from a public road, 3/5 mile west of Elm Creek School, 41h miles northwest of Lockhart, Caldwell County ( 16151). U.S.N.M. no. 76983. Genus TUNDORA Stephensen, n.gen. Type species.-Tundora tuberculata Stephenson. Etymology.-By anagram from rotunda. Gender, feminine. This new genus is a small, rotund shell with a low spire, a small, low protoconch, and a rapidly expanding conch. The or­namentation on the uncallused shell con­sists of narrow to sharp spirals separated by proportionately wide fiat-bottomed in­terspaces in which the incrementals appear as sharp, closely spaced lines. Axials are wanting. In the adult the entire shell is covered with a proportionately thick coat­ing of callus consisting of 2 or more lay­ers. A remarkable peculiarity of this coating is the development over much of its surface of low, round-topped tubercles, most of which are aligned iq rows sur­mounting the concealed spirals; however, scattered nodes are present in the inter­spaces and nodes are absent on the parietal wall in the vicinity of the aperture, and also on the higher parts of the spire. In one meridian of the spire the callus is folded up to form a narrow, prominent axial ridge which extends up to and over the apex, somewhat as in Caly ptraphorus. The four available shells of Tundora tuberculata are all incomplete but the holotype reveals the beginning of an expanded outer lip of undetermined ex­tent. The columella is smooth and the aperture 1s elongated and terminates acutely at the rear; one of the paratypes shows a narrow anal canal impressed in the callus and extending well up on the side of the penultimate whorl. The anterior canal is narrow, recurved and is probably short. The family relationship of this species is not certainly known, but it ap­pears to be a member of the Strombidae. TUNDORA TUBERCULATA Stephenson, n.sp. Pl. 59, figs. 1-4 Shell small, rotund. Spire low; spiral angle 106 degrees at the apex, decreasing rapidly to 55 degrees on the larger whorls below. Protoconch small forming a low, simple, dextral spiral of about 11/2 volu­tions. Whorls 4 or 5, rapidly expanding, broadly rounded on the sides. Suture closely appressed, moderately impressed. Body whorl plump, broadly and regularly rounded from suture to base. The or­namentation on the uncallused body whorl consists of 13 or 14 narrow to sharp spirals separated by proportionately wide, flat-bottomed inters paces; the spirals are strongest on the inflated part of the shell, become weaker below, and nearly fade out on the lower part of the base. The fourth or fifth spiral below the suture is stronger than the others; it increases in strength toward the aperture and may become prominent on an expanded lip, only the beginnings of which are preserved on the three available incomplete specimens. The seventh or eighth spiral below the suture is a little stronger than the nearest adjacent spirals and it also increases in strength toward the aperture; it is slightly bifid on its crest. The whole surface of the adult shell is covered with a proportionately thick cal­lus consisting of 2 or more layers; the spirals are reflected through the callus in accentuated thickness. An unusual fea­ture displayed over much of the callused surface is a series of low, round-topped tubercles, most of which are aligned in rows immediate! y above the spirals; a few isolated tubercles stand in the inters paces; tubercles are wanting on the parietal wall The University of Texas P.ublicatfon No. 4101 at the aperture and on the ~maller whorls of the spire. On portions of the shells from which the surficial layer of callus has been accidentally broken away the incre­mentals appear as sharp, closely spaced lines trending upward and obliquely back­ward somewhat beyond the line of great­est inflation, thence curving around and running obliquely forward and upward to the suture. On one meridian of the spire of the holotype the layer of callus is folded into a narrow, prominent, forward leaning ridge which passes upward over the apex and for at least 2 mm. down over the opposite Eide. Aperture elongated, . of only moderate width, acutely angular at the rear; one paratype bears a remnant of callus showing the imprint of an anal canal extending upward two-thirds of the way across the penultimate whorl. At the anterior end of the aperture is an in­complete, narrow, recurved siphonal canal which is probably not very long in a complete shell. Outer lip partly broken away, but probably thin and more or less expanded. Inner lip forming a thin callus, broadly convex on the parietal wall, excavated low on the base. Columella without folds. Dimensions of the holotype: Height 12.7+ mm., diameter just back of the beginning of the lip expansion 8.5 mm. Types.-Holotype, U.S.N.M. no. 76984; 1 figured paratype, U.S.N.M. no. 76985; 1 unfigured paratype, U.S.N.M. no. 76986; 1 unfigured paratype, U.S.N.M. no. 76987. Distribution in Texas.--Navarro group, l\eylandville marl: Corsicana road, 2Y2 miles north of Corbet, Navarro County t 17365, 1 unfigured paratype; Tex. Bu. I 7300, holotype and 2 paratypes, 1 figured). Family CYPRAEIDAE Genus CYPRAEA Linne CYPRAEA NUCIFORMIS Stephenson, n.sp. Pl. 59, figs. 8-11 Shell of moderate size, thin in younger stages, becoming thick in adults. Spire small, low, conical, becoming completely covered with callus in adults; about three whorls are exposed just preceding the adult stage. The protoconch is not well exposed, The exposed whorls of the spire are broadly rounded, the suture is closely ap· pressed and the surface is ornamented with 8 or 9 fine, rather obscure revolving ridges ,vhich appear to alternate in size. The body ,....horl is relatively very large and plump, and there is no peripheral ridge or angle; the surface where not callused over exhibits rather widely separated, fine, obscure revolving ridges. The aperture is long, narrow, and extends the whole length of the shell; at the top it curves to the left, ending in a well defined, reflected anal channel. The siphonal channel is broken away on all the specimens but is probably short. The outer lip becomes very thick and rounded on the edge, due to the gen· erous deposition of callus both within and without. The inner lip also becomes heavily callused and from both the inner and outer lips the mantle spreads over practically the whole shell, including the spire, covering the surface with polished callus. Both the inner and the outer lip are crenulated at the margin of the aper· ture. Dimensions of the h o l o t y p e: Height 24+ mm., diameter 18 mm. The species differs from Cypraea mor· toni Gabb,365 and from specimens which have been referred to that species by authors, in that the spire is not completely enveloped except as it is covered by callus in the adult stage. The genus is rare in the Upper Cretaceous of the Atlantic and Gulf Coastal Plain. Types.-Holotype, U.S.N.M. no. 76988; 2 figured paratypes, U.S.N.M. no. 21007. Distribution in Texas.-Navarro group, Nacatoch sand: Vicinity of Kaufman (761). CYPRAEA GRACILIS Stephenson, n.sp. Pl. 59, figs. 12, 13 Shell small, thin, relatively slender. Spire low, conical, partly covered by the reflected anal channel; the two partly ex· posed whorls of the spire are very broadly convex to almost flat on the side, and are ornamented with 5 or 6 fine spiral ridges; these are crossed by still finer, rather 363Gal1b, Wm. M., Acad. Nat. Sci. Philadelphia Jour., 2d ser., vol. 4, p. 391, pl. 68, fig. 9, 1860. Invertebrate Fossils of the Navarro Group closely spaced axial ridges which are pres­ent not only in the interspaces but over­ride the spirals. The protoconch is a simple, dextral, broadly conical conch of about two and a half volutions. The large body whorl is broadly rounded and is ornamented with numerous fine, obscure spirals which apparently disappear toward the margin of the aperture. The aperture is long, narrow, and curved, being a little wider anteriorly than posteriorly, and ex­tends the full length of the shell; it is reflected to the left posteriorly, ending in a wide open anal channel; anteriorly the aiphonal channel is broken away. The outer lip is greatly thickened by the deposition of callus, and its inner margin ia crenulated, the nodes numbering about 6 in a distance of 5 mm.; the inner lip is formed of a thin layer of callus which spreads for several millimeters over the thell; the inner lip is also finely crenu­lated, the nodes numbering about 9 in a distance of 5 mm. Dimensions of the holotype: Height IS+ mm., diameter I 0 mm. This species is smaller, thinner and more slender than Cypraea nuciformis; in addi­tion the ornamentation is distinctive and the marginal crenulations of the aperture are much finer. Holotype.-U.S.N.M. no. 20894. Dutribution in Texas.-Navarro group, Nacatoch sand: North edge of Corsicana (518, type loc.); 3/5 to 4/5 mile north­east of Chatfield ( 75 72) . Superfamily RACHIGLOSSA Family PYROPSIDAE Genua PYROPSIS Conrad The genus Pyro psis is founded upon Tuaicla (Pyro psis) perlaJa Conrad, from the Ripley formation of Tippah County, Mississippi. Conrad later raised the sub­generic name to the rank of genus. The type of Conrad's species is preserved in the Academy of Natural Sciences of Phila­delphia.868 PYROPSIS LANHAMI Stephenson, n.ap. Pl. 59, figs. 14-16 Shell of moderate size, rather thick, with about 3% whorls. Spire very low and -COnrad, T. A., Acad. Nat. Sci. Philadelphia Jour., 2d ....., YOJ. 4, p. 288, pJ. 46, 61. 39, 1360. flattish. Protoconch poorly preserved but apparently a simple, flattish, dextral conch, coiled 1112 or 2 times. The whorls expand rapidly and the body whorl is large and strongly inflated above. The suture is closely impressed, and is at the inner edge of a deep flat-bottomed groove which ex­pands regularly toward the aperture. The periphery of the body whorl forms an approximate right angle, below which the base descends steeply with a broadly con­vex contour to a strong basal constriction. The upper flattish surface of each whorl is slightly excavated and is bordered on each side by a row of obscure nodes. This upper surf ace is smooth from the aperture back to and including more than half of the penultimate whorl; the posterior part of the penultimate whorl and the ante­penultimate whorl are covered with nu­merous fine, obscure, spiral ridges. The body whorl between the periphery and the basal constriction is ornamented with 9 moderately strong, spiral, nodose ribs; the nodes are small and number 6 or 7 to the centimeter, the ones on the peripheral rib being a little coarser than those on the ribs below; the nodes are arranged in vertical rows which mark small, obscure axial ribs; the spiral ribbing is continued at least on the upper part of the siphonal ex­tension, most of wihch is broken away on the holotype. The aperture is broadly subovate and slightly flaring in the adult; a faint anal channel and a more pro­nounced angulation at the terminus of the periphery give to the posterior part of the aperture a wide, squarish margin. The outer lip is thick and feebly notched at the ends of the spiral ribs; on the inner sur­f ace, paralleling the margin of the outer Iip and about 3 mm. from it is a low, obscurely nodose ridge. The inner lip forms a layer of callus spreading forward several millimeters on the base of the body whor1; this layer is thin above, thicker below, and at the lower part of the aper­ture rises in a sharp fold from the main shell surface, forming a deep umbilical fissure. The aperture is continued forward in a deep, narrow siphonal channel most of which is broken away. Dimensions of the incomplete holotype: Height 26+ mm., diameter 27 mm. This elegant shell is smaller, and more regularly o r n am e n t e d than Pyro psis The University of Texas Publication No. 4101 perlata Conrad, the type specie~ of the genus, from the Ripley formation in Tippah County, Mississippi~ it al~o la<'b the prominent peripheral keel of that species. Compared with P. proxima Wade, from Coon Creek, Tennessee, this species is smaller more res.-The species from Coon Creek, Tenrws~cc, identified hy Wade as Peris­ solax lvhitfie/di (Weller), is here desig· natcd p:cnotype. Etymology.--Diminntivc of napus (Latin), a turnip. According to Whitfield:110 and Stewart,m Fusus trivolvus Gabb, from the Vincen­town sand of New Jersey, must be taken as the type species of P~rissolax, a genus proposed by Gabb312 in 1861. The Vin· centown sand, supposed by Gabb to be Cretaceous, is now known to be Eocene. Gabb referred the Cretaceous species Ficus octolfrata Conrad to Per£ssolax, and Wade referred Pyropsis whitfieldi Weller, also Cretaceous, to that genus. Although these species resemble Perissolax in form, they are much smaller and their protoconchs compared with the Eocene species, Fulgu; eocense Aldrich,a73 which Stewart believes to be congeneric with Perissolax, are much smaller and not so clearly differentiated from the main shell; in both, however, the protoconch is erect, a feature which clearly distinguishes Perissola.x and Napulus from Pyropsis and Medionapus, whose proto· conchs are nearly flat. The species here referred to Napulus are all small, not exceeding 32 mm. in height, have plumper body whorls than that of Pyropsis, and lack the prominent periph· eral angle of that genus. The siphonal canal is long and slightly curved. The body whorl is strongly constricted below, and its main inflated part bears 6 to 9, nearly evenly spaced, spiral ribs which may be prominently or only obscurely noded. The protoconch is small, strongly elevated, and is not sharply separated from the main conch. There is no um­bilical fissure. The columella is without folds, but is slightly swollen at the upper end of the si phonal canal. 370Whitficld, R. P., U. S. Geo]. Survey Mon., vol. 18, pp. 34, -16, and 172, 1892. (Geo!. Survey New Jersey, Paleontology, vol. 2, pp. 34, 46, and 172, 1892.) 371Stcwart, Ralph B., Ac:id. i~at. Sci. Philadelphia Proc., vol. i8, p. 427, 1927; Acad. N.i.t. Sci. Philadelphia Special Pub. J',;o. 3. p. 41, 1930. a7:!Gahb, Wm. M., Synopsis of the l\follusca of the CretacPous formation, p. 66. (Also in Proc. Amer. Philos. Snc .. vol. a. p. 122, 1861.) 373Aldrich, 1'. H., Eull. Am. Paleontology, vol, I, No. 2, p. 62, pl. 3, figs. 7, 7a, 1895. See also Harris, G. D., Bull. Am. Paleontology, vol. 3, no. II, p. GS, pl. 8, fig. 13, 1899. Invertebrate Fossils of the Navarro Group 1'he genus is ba&ed on the species repre­sented by the shell from the Coon Creek tongue of the Ripley formation, at Coon Creek, McNairy County, Tennessee, whi~h Wade87f described and figured as P eris­solas whitfieldi (Weller). There is reason to doubt the correctness of Wade's specific identification, but whatever name may eventually be applied to it, the Coon Creek species is designated the genotype of Napulus. Napulus whitfieldi (Weller), of Wade, is the largest of the species referred to this new genus; its height is 32 mm. and its diameter 19 mm. The following previously described species are regarded as belonging to this genus. Ficus octolira.ta Conrad, Fusus relifer Gabb, Dolium (Dolio psis?) multi­ liratum Whitfield, Pyro psis lenolensis Weller, and Pyropsis whitfieldi Weller. With the exception of Ficus octolirata Conrad, these species are based on poor material and some of them may be syno­ nyms. The several species referred to this genus appear to form a compact group of gastropods in the Upper Cretaceous of the Atlantic and Gulf Coastal Plain; with one or two exceptions these species are in the Exogyra costata zone. A relatively large species from near Chatfield, Navarro County, Texas, de­scribed by Shumard375 under the name Ficw (Pyrifusus} granosus, probably belongs to Napulus, but the type is lost and the species has not been identified in collections subsequently made in the vicin­ity of Chatfield. NAPULUS TUBERCULA TUS Stephenson, n.ap. Pl. 60, figs. 3-6 Shell small, thin, pyriform, with about two and a half whorls. Spire low with plump whorls. Protoconch small, ele­vated, coiled one and a half or two times. The whorls expand rapidly and the body whorl is plumply inflated above, becom­ing sharply constricted below, passing into a long siphonal extension. Suture closely appressed, moderately impressed, bordered below by a flattish hand, which forms a "'Wade, Bruce, U. S. Geol. Survey Prof. Paper 137, p. 1•1. pl. 49, 619. 6, 9, 1926. "'Shumard, B. F., Description• of new Cretaceous fos· .0. from Te:u1: Boeton Soc. Nat. Hitt. Proc., vol. 8, •· 196. shoulder of moderate width. The penulti­mate and antepenultimate whorls are ornamented with 2 moderate! y prominent spiral ribs, which divide the surface into three nearly equal bands, the upper one of which forms the flattish shoulder; both ribs are ohscurel y tuberculated. The inflated part of the body whorl hears 8 spiral ribs, which decrease in prom­inence from above downward; all these ribs are tuherculated, but the one bordering the shoulder hand has the strongest tubercles and the tubercles on the successive ribs below become pro­gressively less pronounced; the tubercles on the different ribs are arranged in verti­cal rows and are faintly connected across the interspaces, thus giving rise to fine, obscure axials; fine, obscure spiral lines can he detected on the shoulder hand; spiral ribbing continues out onto the siphonal extension of the body whorl; the ribs are reflected on the inner surf ace of the body whorl as shallow spiral chan­nels. The aperture is subovate, squarish posteriorly at the end of the shoulder hand, and extends anteriorly in a long, narrow, slightly curved siphonal channel. The outer lip is thin and simple, except for the notching produced by the channels on the inner surface; the inner lip is broadly ex­cavated and forms a thin callus extending somewhat forward on the base of the shell. Dimensions of the incomplete holo­type: Height 12 +mm., diameter 9.6 mm. The figured paratype measures: Height 14.3 mm., diameter 8.7 mm. The tuberculated spiral ribs of this species distinguish it from N apulus octo­liratus (Conrad), from the Owl Creek formation at Owl Creek, Mississippi; the ribs on Conrad's species are also a little wider and more squarish in cross section. Napulus whitfieldi (Weller)?, from Coon Creek, Tennessee, is a larger species with fewer spirals. Types.-Holotype, U.S.N.M. no. 76998; 1 figured paratype, U.S.N.M. no. 20911. Distribution in Texas.-Navarro group, Neylandville marl: 21/2 miles north of Corbet ( 17365) . Navarro group, Nacatoch sand: Vicinity of Corsicana ( 763, type loc.) ; vicinity of Chatfield ( 762) ; 3/5 to 4/5 mile northeast of Chatfield (14117). The University of Texas Publfration No. 4101 N.APULUS OCTOLIRATUS (Conrad)? Pl. 60, fip;s. 7, 8 1858. Ficus nctolfratus Conrad, Acad. Nat. S<'i. Philadelphia .lom., 2d ~wr., ml. ~. JI. 332, pl. 35, fig. 6. Shell small, thin, pyriform. with two and a half or three whorls. In size an8, lJ.S.N.M. no. 77000; 16160, U.S. N.M. no. 77001), have the typical form of Napulus, with, however, only 5 spiral ribs impressed upon the mold. A similar internal mold from the Corsi­cana marl in a public road, 1 4/5 miles N. 20° W. of Tona siding, in Hunt County ( 15545), also has 5 spiral ribs (pl. 59, fig. 6). U.S.N.M. no. 77002. An internal mold from the Corsicana marl in a westward-facing bluff on Guada. lupe River, 1 3/10 miles north of Mc­Queeney, Guadalupe County (15524), reflects 7 rather sharp spiral ribs, with faint axial ribs spaced in such a manner as to divide the surface into small squares and rectangles; the spirals are tuberculated at the intersections of the axials, the nodes on the two upper spirals being distinct, and those on the others below obscure. The two lower spirals are smaller than the others (pl. 59, fig. 7). U.S.N.M. no. 77003. An internal mold found with the pre­ceding (15524) has 8 or 9 spirals and appears to lack the axials and tubercles. U.S.N.M. no. 77004.. An internal mold which may be the same species as the preceding was found in the Corsicana mar1 on San Marcos River, 1/2 mile below Martindale, Caldwell County (15526). U.S.N.M. no. 77005. A badly crushed internal mold from the Corsicana mar1 on the Mexia road, 23;4 miles east of Cooledge, Limestone County ( 13832), has 10 or 11 spiral ribs which appear to be finely tuberculated (pl. 59, fig. 5). U.S.N.M. no. 77006. One imperfect shell from the Kemp clay in a field east of the Austin-Elgin road, 314 miles east by north of Manor, Travis County (13861), appears to be a Napulus. It is about as large as the large species of N apulus which Wade376 described under the name Perissolax whitfieldi (Weller). Compared with the Coon Creek species this one has a more pronounced shoulder, and the spirals on the body whorl, which are similarly spaced, are thicker and more 370Wade, Bruce, U. S. Geol. Survey Prof. Paper 137, p. 141, pl. 49, figs. 6, 9, 1926. Invertebrate Fossils of the Navarro Group prominent; they are, however, similar!y noded. U.S.N.M. no. 77007. Genus HERCORHYNCUS Conrad 1860. Fusus Conrad, Acad. Nat. Sci. Philadelphia Jour., 2d ser., vol. 4, p. 286. ( == Fusus tippana Conrad.) 1869. Hercorhyncus Conrad, Amer. Jour. Conch., vol. 4, p. 247. Type species.-Fusus tippana Conrad. The type species of this. genus, H~rcor­hyncus tippanum Conrad, is from T1pp~h County Mississippi, but the exact locality was nof stated by Conrad. A similar, but apparently more slender, unnamed species occurs at Owl Creek, 21/2 miles northeast of Ripley, Tippah County. The shell which Wade377 described under the name Serrifusus tennesseensis appears to be congeneric with Hercorhyncus tip­panum Conrad; it has a shorter spire, the excavated band below the shoulder is nearly smooth, and the canal appears to be more strongly bent. Serrifusus Meek, though closely related, appears to be ge­nerically distinct. Haplovoluta Wade378 from Coon Creek, Tennessee, is closely allied to Hercor­hyncus Conrad, but the presence of a dis­tinct sulcus at the base of the body whorl, and much more numerous spinose nodes on the periphery, seem to justify a generic separation. The Texas species, H. malleifor me, is more closely related to the genotype, Hercorhyncus tippanum Conrad, than it is to either the Owl Creek or the Coon Creek species. HERCORHYNCUS MALLEIFORME Stephenson, n.sp. Pl. 61, figs. 10, 11 Shell of medium size, rather thick, mallet-shaped, with 4 or 5 volutions. Spire of moderate height; the whorls increase rapidly in size, and the anal fasciole on the penultimate and smaller whorls is broadly excavated below the suture. Pro­toconch broken away. Suture closely appressed and distinctly impressed, bor­dered below by a well developed collar which forms the upper slope of the ex­cavated band. Bordering the excavated 877Wclde, Bruce, U. S. Geo]. Surn~y Prof. Paper 137, P• 143, pl. 50, figs. 3, 4, 1926. tr180p. cit., p. 138. band below is a row of coarse, rounded nodes of somewhat irregular size and spac­ing, numbering 11 on the penultimate and 9 on the antepenultimate whor1. The con­tinuation of the excavated band becomes a pronounced shoulder on the body whorl where the nodes number 11 and are quite prominent and coarse, forming blunt axials which die out a few millimeters below the periphery. The anal fasciole bears 6 small, closeIy crowded, spiral ridges, the 3 lower ones of which override the nodes, the lowest one passing over the crests of the nodes. The body whorl below the shoulder angle is ornamented with spiral ribs of moderate size; the fifth one below the shoulder is more than twice as large as the others and forms a periph­eral ridge, below which the base de­scends steeply and rounds broadly into the anterior extension; the primary spiral ribs below the peripheral ridge are larger and more wideIy spaced than those above it, and 2 or 3 small minor ribs, poorly pre­served, are present in each of the inter­spaces; the ribbing dies out about halfway out on the canal. Aperture subovate, squarish posteriorly at the end of the anal fasciole; the anal channel forms a distinct, narrow notch at the end of the collar; siphonal channel slightly curved and about as long as the main aperture, separated from the columella by a narrow fissure. The outer lip is partly broken away. The inner lip forms a broadly excavated, moderately thick callus. Dimensions of the holotype: Height 45+ mm., diameter 24 mm. Closely allied species are H. vadosum, H. tippanum Conrad (the genotype) from the upper part of the Ripley formation at Owl Creek, Tippah County, Mississippi, and H. tennesseense (Wade) from the lower part of the Ripley formation (Coon Creek tongue), from Coon Creek, McNairy County, Tennessee. On H. tippanum, a smaller shell, the excavated shoulder band lacks revolving ribs, and its anterior canal is proportionally shorter and a little more twisted than that of H. malleifor me, but the two are very closely related. Holotype.-U.S.N.M. no. 77008. Distribution in Texas.--Navarro group, Kemp clay: West of Zuehl (7721, type The University of Texas Publication No. 4101 loc.) ; Webberville (7601) ; near Deats­ville (761·, 14125) ; Littig (765) ; 2 2/5 miles southeast of Manor (18196). HERCORHYNCUS VADOSUM Stephenson, n.sp. Pl. 61, figs. 18-20 This shell is closely related to H. rnallei­fonne, but differs in several details. The general form and size are about the same, but vadoswn is somewhat more finely sculptured and the shoulder band is mark­edly more shallow, and therefore more gently sloping; the shoulder is a little more obtuse and the shoulder nodes more numerous (14 on the body whorl) and not quite so prominent; the nodes may be somewhat waterworn. Spiral ribs are wanting on the anal fasciole, but several weak spirals appear on the upper flanks of the shoulder nodes; four or five spirals appear on the body whorl between the shoulder angle and the periphery; the peripheral ridge bears three obscure minor spirals; the spirals on the base are more closely crowded and number seven or eight. The inner lip forms a thick callus on the parietal wall. On the two available shells the apical whorls and the anterior canals are both broken away. Dimensions of the holotype: Height 38+ mm., diameter 27. Types.-Holotype, U.S.N.M. no. 77009; 1 paratype, U.S.N.M. no. 77010. Distribution in T exas.-Navarro group, Nacatoch sand: Vicinity of Kaufman (761). HERCORHYNCUS NODOSUM Stephenson, n.sp. Pl. 61, figs. 14, 15 Shell of medium size, pyriform, with about 4 vol utions. Spire of moderate height increasing rapidly in size; spiral angle about 75 degrees; anal fasciole broadly excavated. Protoconch not pre­served. Suture closely appressed, deeply impressed, bordered below by a well de­fined collar of moderate width. On the shoulder is a row of prominent, thick nodes slightly elongated axially; these number 10 on the body whorl and 8 or 9 on the penultimate and on the antepenulti­mate whorls; on the body whorl the nodes end almost abruptly a little below the shoulder. The body whorl is covered on its side and base with numerous, well de­veloped, narrow, roughly round-crested spirals which are narrower than the inter· spaces; a pair of these form a broadly obtuse peripheral ridge a little below the ends of the large axial nodes; five of the spirals are above this shoulder and the upper two or three of them override the large nodes; ten of them are below the pair on the base and on the upper part of the canal. The anal fasciole bears nu· merous small and very obscure spirals. Aperture elongate-lanceolate with the widest part just below the shoulder angle; anal channel acute; anteriorly the aperture becomes narrow and passes into the siphonal canal which is broken off in the holotype. The outer lip, which is incom­plete, is angulated at the shoulder and broadly arched below. The inner lip is broadly excavated above and forms a thin callus over the parietal wall; below the callus it is slightly separated from the wall of the siphonal canal by a long, narrow fissure. Columella apparently smooth. Dimensions of the incomplete holo­type: Height 25+ mm., diameter about 16 mm. The species differs from H ercorhyncus malleiforme in the fewer, more widely separated and more prominent axial nodes, and in its finer spiral sculpture; H. vadosum exhibits a similar spiral sculpture but has more numerous, more closely spaced, and less prominent axial nodes. Holotype.--U.S.N.M. no. 77011. Distribution in T exas.---Navarro group~ Neylandville marl: 21h miles north of Corbet (Tex. Bu. 17300). HERCORHYNCUS MUNDUM Stephenson, n.sp. Pl. 61, figs. 16, 17 Shell of medium size and elegant con· tour. Spire of moderate height; apical angle about 65 degrees, spreading to 80 degrees on the larger whorls below. Suture closely appressed, deeply im· pressed. Anal fasciole broadly and rather deeply excavated, forming a pronounced collar below the suture. The axials num· her 11 or 12 on each of the three larger whorls and are about coequal in width with the inters paces; the axials are rather Invertebrate Fossils of the Navarro Group thick, of only moderate prominence and on the body whorl extend from the shoulder down the side, fading out high on the base. The spirals are rather weak and widely spaced on the upper part of the body whorl and override the axials; the two upper ones are closer together than the others and form a pair on the shoulder; on the base are 5 or 6 more prominent spirals which increase in size and width of spacing from above down­ ward, but appear to fade out on the upper part of the incomplete si phonal canal; spirals are wanting on the anal fasciole. The incrementals appear rather coarse u the shell is preserved; they are sinuous in trend and bend markedly forward as they cross the anal f asciole. Aperture wide above but narrowing abruptly to an acute anal channel; below the aperture narrows to an elongated siphonal canal which is incomplete in the holotype. Outer lip partly broken away; it is broadly arched outward above becoming slight! y concave below. Inner lip broadly ex­ cavated above where it forms a thin callus over the parietal wall; below the callus is slightly separated from the wall of the eiphonal channel, forming a narrow fis­ sure. The columella appears to be smooth. Dimension of the incomplete holotype: Height 24+ mm., diameter 14 mm. This shell differs in detail of sculpture and form from the other three species and is easily recognized as a separate species. The axials are more numerous, more elongated, and much less prominent than those of H ercorhyncus nodosum in the same formation. Types.-Holotype, U.S.N.M. no. 77012; 1 unfigured paratype, U.S.N.M. no. 77013. Distribution in Texas.-Navarro group, Neylandville marl: 2% miles north of Corbet ( 17365; Tex. Bu. 17300, type lot) . HERCORHYNCUS CORONAL£ StephenHn, n.ap. Pl. 61, figs. 12, 13 Shell of medium size, ventricose. Spire about half the total height of the shell, spiral angle 70°. Protoconch and one or two coils of spire broken away. Whorls 4 or 5, closely appressed, rapidly expand­ ing. Suture deeply impressed. Body whor 1 elongated, inflated above, sharply compressed below. Shoulder wide, steeply sloping, broadly excavated. Axial sculp­ture consisting of regularly spaced, prom­inent, pointed nodes on the shoulder an­gle, numbering 9 on the body whorl, and 8 on the penultimate whorl. The body whorl below the shoulder nodes is or­namented with spirals distributed as fol­lows: Just below the nodes are 3 small spirals, narrower than the inters paces; on the perimeter is a strong broad, slightly hifid rib; on the base are 7 or 8 flattish­topped spirals which are narrower than the inters paces; 4 or 5 of the upper ones are moderately strong, the others below becoming successively weaker and fading out about halfway out on the anterior prolongation. Spirals are wanting on the shoulder of the body whorl, hut on the penultimate whorl, numerous fine, microscopic threads override the shoulder nodes. The trend of the growth lines is broadly convex forward as they pass up over the base; as they cross the shoulder they bend first backward and then forward to the suture. Aperture wide above, acutely angular at the rear, narrowing quickly to a long, narrow siphonal canal in front. Outer lip thin, nearly rectangular at the intersection of the shoulder angle. Inner lip broadly excavated on the sharply constricted base. Dimensions of the incomplete holotype: Height 22.5 mm., diameter 13 mm. The species differs from the other species of the genus in its more elevated shoulder and in the sharpness and wider spacing of the nodes on its shoulder angle. The species appears to he most closely related to H. nodosum Stephenson. Holotype.-U.S.N.M. no. 77014. Distribution in Texas.-Navarro group, N acatoch sand: 2% miles west by south of the courthouse at Corsicana ( 17368) . Unidentified apeclmena of HERCORHYNCUS Imperfectly preserved specimens proh­ bl y belonging to H ercorhyncus have been found at localities in the Corsicana marl as enumerated below. These are all closely similar in form and sculpture to H. malleiforme but they lack the deeply The Univ~rsit-y of Texas Publication No. 4101 excavated shoulder and the strongly developed collar below the suture, and should probably be treated as one or more distinct species. The localities are: Guadalupe River. 1 3/ 10 miles above Mc­Queeney, Guadalupe C o u n t y (7637, U.S.N.M. no. 77015; 15524, U.S.N.M. no. 77016) · 2 miles south of Marion, Guada­lupe -County (13389, U.S.N.M. no. 77017) ; public road, 4/ 5 mile south of the Castroville road, just east of the old fuller's earth pits, 14. miles west by south of San Antonio, Bexar County (15623, U.S.N.M. no. 77018); pit of Standard Fuller's Earth Company, 4/ 5 mile north of Castroville road, 14 miles west of San Antonio (15520, U.S.N.M. no. 77019). Family BUSYCONIDAE Genus BUSYCON Bolten BUSYCON? sp. Pl. 62, fig. 10 The incomplete internal and external molds of a large gastropod, found in the Nacatoch sand on land of E. A. Stevens, 1 4/ 5 miles northeast of Quinlan, Hunt County (16162), is similar in form to Busy con ( Protobusrcon) cretacewn Wade3 rn from Coon Creek, Tennessee, but lacks a spiral sulcus at the base of the body whorl, a feature which served as the basis for Wade's subgenus, Protobusycon. The growth lines over the part preserved are vigorous and closely crowded. Numer­ous fine spiral lirae are only faintly discernible, but their obscurity may be due to imperfection of preservation. The anaular shoulder or periphery bears ir­re;ular, elongated protuberances as in Wade's species. The second obscure keel outlining the base of the body, described by Wade, is scarcely defined hut the Texas shell is larger and more mature and even on the younger stage represented by the Tennessee shell this feature is al­ready tending to smooth out and disap­pear toward the aperture. The general similarity of the Texas shell to the one from Tennessee suggests the possibility that the sulcus at the base of the body whorl on the latter may be a pathologic 370Wade, Bruce, U. S. Geo!. Survey Prof. Paper 137, p. 136, pl. 47, figs. I, 4, 1926. feature due to a mantle Injury, hut this possibility can not be checked until more shells of this kind are obtained from the Coon Creek locality. U .S.N .M. no. 77070. Genus PINELLA Stephenson, n.ren. Type species.-Pinella reticulata Stephenson. Etymology.-Diminutive of pinea (Latin), a pine cone. Shell small, mod era tel y thick. Spire low, with angle of about 80 degrees. Whorls three, increasing rapidly in size; body whorl very large, more than twice as hio-h as the spire. Shoulder moderately wide, sloping, slightly excavated, making an obtuse angle with the side below. Sur­face reticulated bv numerous, narrow, closely spaced axials, and fewer, thicker, more prominent, and more widely spaced spirals. Aperture somewhat deformed by mechanical pressure, hut evidently rather widely gaping with an obtuse notch at the shoulder angle; anal canal shallow; siphonal canal short, deep, moderately wide, and markedly twisted; this canal is bordered above by a distinct, oblique columellar fold. The inner lip forms a very thin wash of callus on the parietal wall and columella. In form this shell resembles Busycon, hut it is very much smaller and the anterior canal is shorter and is decidedly twisted; the sculpture is also much more strongly accentuated. PINELLA RETICULATA Stephenson, n.ap. Pl. 60, figs. 1, 2 The species is based on one individual. Shell small, moderately thick. Spire low with an apical angle of about 80 degrees. Protoconch broken away, hut small as indicated by the scar. Whorls three, in­creasing rapidly in size. Body whorl re!a· tively very large, being more than t~1ce a5 high as the spire. Shoulder of medmm width, sloping, slightly excavated, meet· ina the side of the whorl at an obtuse an~le. Surface finely reticulated with axial and spiral ribs. The axials are nar· row, closely spaced and number about 48 on the body whorl and 30 on the penultimate; they override the spirals, bend forward above where they cross the Invertebrate Fossils of the Navarro Group shoulder which is without spirals, and ex· tend below to the base of the body. The spirals are much broader and more widely spaced than the axials, and number about a dozen on the body whorl between the shoulder angle and the base of the body. The external surface on the pillar in front of the siphonal canal is covered with small, closely spaced, rather obscure spirals. Aperture elongate-subovate, with a shallow anal canal at the rear, which produces an angle a little less than a right angle at the junction of the outer lip with the body; the siphonal canal in front is rather short, but deep and mod­ erately wide and is markedly twisted. The outer lip is broken and irregular but it is broadly notched at the shoulder angle; inner lip broadly excavated and forming a thin callus over the parietal wall and columella. The columella is twisted and bears a distinct fold below at the upper border of the anterior canal. Dimensions: Height about 11 mm., diameter about 6.5 mm. Holotype.-U.S.N.M. no. 77020. Diatribution in Texas.-Navarro group, Kemp clay: West of Zuehl ( 7721) . Family SARGANIDAE C.nua SARGANA Stephenaon 1907. Rapana Schumacher. Weller, Geol. Sur· vey New Jersey, Paleontology, vol. 4, p. 754, pl. 89, figs. 1-3. 1923. Sar1ana Stephenson, North Carolina Geol. and Econ. Survey, vol. 5, p. 377, pl. 93, figs. 1-5. Type species.-Rapana stantoni Weller. The type species of this genus, Sargana 1tantoni (Weller) , is from the N acatoch sand, near Chatfield, Navarro County, Texas. Weller placed the genus in the family Purpuridae and W ade880 in the family Muricidae, but the low spire, the presence of a columellar fold, and the absence of prominent spines and varices, eerve to distinguish the genus from these families and warrant the recognition of the family Sarganidae to include it and related species. Wade's genus Schizobasis should he classed either in this family, -.Vacle, Brace, U. S. Ceol. Suney Prof. Paper 137, •· 18', 1926 or in a closely parallel family, instead of in the Turbinidae to which he referred it. This is indicated by the presence of a nar­ row, deep si phonal canal like that in Sargana, the presence of two columellar folds, and by the flaring, coarse! y and irregularly notched margin of the umbili­ cal fissure. The genus is represented in the Creta­ ceous of Pondoland, southeast Africa, by Pyro psis geversi Rennie,881 a species which, judged by the published figures, is remarkably close to Sargana stantoni. SARGANA STANTON! (Weller) Pl. 60, figs. 15-17 1907. Rapana stantoni Weller, New Jersey Geol. Survey, Paleontology, vol. 4, p. 754, pl. 89, figs. 1-3. 1923. Sargana stantoni (Weller). Stephenson, North Carolina Geol. and Econ. Survey, vol. 5, p. 377, pl. 93, figs. 1-5. 1926. Sargana stantoni (Weller). Wade, U.S. Geol. Survey Prof. Paper 137, p. 136, pl. 46, figs. 7, 8. Shell of moderate size, thick, subpyri­form, with 3 or 4 rapidly expanding volu­tions. Protoconch small, simple, slightly elevated, not sharply separated from the conch. Spire very low, the exposed sur­face of the whorls being almost flat. Suture closely appressed. Body whorl sharply angular at the periphery in young individuals, becoming subangular in adults. Body whorl sharply constricted at the base. The upper surface of the conch is smooth at its small end, but within 10 or 12 mm. 3 rows of small spinose nodes appear, one on the inner and one on the outer border, and one in the middle; these nodes gradually in­crease in prominence and gradually come to occupy the crests of ill-defined spiral ribs; longitudinally the nodes are aligned in oblique rows which mark obscure axials. The flattish exposed surf ace of the whorls of the spire becomes a slightly sloping shoulder on the body whorl, and the spinose nodes become continuously more pronounced toward the aperture, the 881Rennie. John V. L., New Lamellibranchia and Gaetropoda from the Upper Cretaceous of Pondoland (with an appendix on some species from the Cretaceous of Zululand) : Annals of the South African Museum, vol. 28, pt. 2. p. 229, pl. 27, fip. 17-19, 1930. The University of Texas Publication No. 4101 outer row f o r m i n g the subangular periphery; 4 additional spinose spirals adorn the body whorl below the periphery, making 7 spirals in all; the nodes mark t.he intersection of moderately pronounced axials of irregular strength and spacing, with the spiral ribs. Resting stages in the growth of the shell are indicated by broader and deeper axial depressions be­tween rows of nodes. The constriction at the base of the body whorl is emphasized by a rather broad rugose sulcus, below which is another row of irregular spines, marking an ill-defined spiral. The spines are formed by sharp upfolds of growth lamellae concave toward the aperture. The aperture is subcircular or broadly subovate; the margin is modified pos­teriorly by a distinct anal notch, and an­terior I y is slit by its junction with a nar­row, deep, twisted si phonal channel; the inner lip forms a thick callus. The shell is characterized by a deep, expanding umbilicus, the outer margin of which is coarse I y notched and becomes progres­sively more attenuated anteriorly; the inner surface of the umbilicus is marked by radiating grooves which intersect the margin at the bottoms of the notches. A broken shell from Mississippi shows a narrow, sharp columellar fold bordering the inner margin of the si phonal slit. Dimensions of the holotype: Height 24 mm., diameter 24.5 mm. The reported occurrence of the species in the Marshalltown formation (Exogyra ponderosa zone) of New Jersey, by Weller, has not been confirmed. Types.-Holotype, U.S.N.M. no. 21070; 3 paratypes, U.S.N.M. no. 77021. Distribution in Texas.--Navarro group, Neylandville marl: ?Y2 mile north of Cooper (4064). Navarro group, Nacatoch sand: Vicinity of Chatfield ( 762, type loc.) ; 4fs mile north of Hester (Tex. Bu. 17306) ; vicinity of Corsicana (763). Outside distribution.-Tennessee: Coon Creek tongue of Ripley formation. Mississippi: Ripley formation. Chattahoochee region ( A 1a b a m a ­ Georgia) : Upper part of Ripley forma­tion. North Carolina: Peedee formation (upper part). Range.--So far as definitely known this species is limited in its stratigraphic range to the Exogyra costata zone. Poorly pre· served shells belonging to lhe genus, but probably to different species, are known in the Exogyra ponderosa zone in North Carolina and New Jersey. Family MOREIDAE Genus MOREA Conrad The genus Morea has been assigned by different authors to the families Cancel­lariidae, Purpuridae, and Buccinidae, all of which are based on Recent genera. Mor ea differs from Purpura Bruguiere not only in contour and the sculpture of the shell, but in having a sharply defined fold on the columella. Morea differs from Cancellaria Lamarck in contour, in the character of the sculpture, and in having only one fold low on the columella, bor­dering the siphonal channel, instead of several folds well above the siphonal chan­nel. Buccinum Linne has a higher spire and a different type of sculpture. These differences seem to justify the recognition of a separate family to include the Creta· ceous shells. The genus Morea is repre­sented in the Upper Cretaceous of the Atlantic and Gulf Coastal Plain by 5 or 6 closely related species, and is herewith proposed as the type genus of the new family. The type species of the genus is Morea cancellaria Conrad from the Ripley formation at Eufaula, Alabama. MOREA CANCELLARIA CORSICANENSIS Stephenson, n.var. Pl. 61, figs. 7-9 Shell of moderate size, thick, subpyri· form, with 4 whorls. Spire low with plumply rounded volutions. Protoconch poorly preserved, but apparently small, smooth, and moderate! y elevated. Suture deeply impressed, closely appressed in the young and intermediate stages, opening out in adults. Body whorl proportionately very large, broadly rounded in contour, slightly constricted anteriorly. Surface of hodv whorl ornamented with 8 or 9 Invertebrate Fossils of the Navarro Group prominent, square-topped spiral ribs, croased by less prominent, slightly wider, but a little more closely spaced axial ribs; the intersection of the two types of ribs is marked by moderately prominent square or rectangular nodes. The upper or pos­terior spiral rib is a little wider than the others, and the inters pace just below it ia a little wider and deeper than the other interspaces. Three of the spiral ribs are exposed on the penultimate whorl. The aperture is elongate-ovate, with a distinct anal notch at the rear, and with a short twisted siphonal canal forming a deep wide notch in front; the upper margin of the canal is bordered by a pronounced columellar fold which follows the twist of the canal back into the shell. An­teriorly there is a broad, deep, twisted false umbilicus bordered on the side of the columella by the sharp edge of the inner lip, and on the other side by a rough, twisted, convex, spirally striated band; both this band and the inner sur­face of the umbilicus are roughened by fine, sharp, closely spaced growth ridges. The outer lip is beveled to a rather thin edge which is notched at the intersection of the spiral ribs; the inner lip forms a thin callus over the base of the shell above the false umbilicus. Dimensions of the incomplete holotype: Height 35+ mm., diameter 28 mm. Dimensions of the accompanying para­type: Height 25.5+ mm., diameter 20mm. The typical Morea cancellaria Conrad was reported by Conrad382 to have been found at Eufaula, Alabama, and in Tippah County, Mississippi, but he did not state at which of these places the figured speci­men was obtained. Specimens from Eufaula agree well with the published figure but the type specimen is lost. In the absence of knowledge to the contrary the first named place, Eufaula, may he accepted as the type locality. The typical M. cancellaria has a higher spire, and is proportionately more slender than the variety cor&icanensis; in addition the axial ribs are narrower and more closely spaced -CO..rad, T. A., Acad. Nat. Sci. Philadelphia Jour., 2d ..... YOL 4, l>• 290, pL 46, 1860. &,. 30, in the Eufaula shells and the prominent spiral rib just below the suture is less distinctly nodose, the nodes showing :1 tendency to become narrower and to as· some a lamellar form in the adult stage. The variety corsicanensis has a shorter spire and is plumper than the variety crassa described below. M. reticulata Stephenson, from the Snow Hill member of the Black Creek formation, Snow Hill, North Carolina, is a more slender and more finely ornamented shell. Types.-Holotype, U.S.N.M. no. 77022; 1 figured paratype, U.S.N.M. no. 77023. Distribut-ion in Texas.-Navarro group, Nacatoch sand: North edge of Corsicana (518). MOREA CANCELLARIA CRASSA Stephenson, n.var. Pl. 61, figs. 5, 6 In form and in type of sculpture this variety is very much like the typical Morea cancellaria Conrad, but the spiral and axial ribs are thicker and the latter are more widely spaced, thus producing a coarser cancellation. In addition the first interspace below the upper or posterior spiral in crassa is narrower and shallower than is the corresponding interspace in the typical cancellaria. Compared with the variety corsicanensis the variety crassa is more slender and has a higher spire. Four of the spiral ribs are exposed on the penultimate whorl. Dimensions of the incomplete holo­type: Height 29+ mm., diameter 18+ mm. H olotype.-U.S.N.M. no. 77024. Distribut-ion in Texas.-Navarro group, Nacatoch sand: 2~ miles north of Corsi­cana (14114, holotype); north edge of Corsicana (518); 4/5 mile north of Hester (Tex. Bu. 17306); vicinity of Chatfield (762); ?vicinity of Kaufman (761). MOREA MARYLANDICA BELLA Stephenson, n.var. Pl. 61, figs. 1, 2 Shell of moderate size and thickness, suhpyriform, with 3 or 4 whorls. Whorls of the spire plumply rounded; spiral angle 80 to 85 degrees. The protoconch is small simple and moderately elevated, but is no; The University of Texas Publication No. 4101 welJ preserved in the types. Suture deeply impressed. Body whorl large, moderately plump, broadly rounded in contour; the upper part of the whorl curves in rather sharply; in the larger of the two paratypes this curvature is strong enough to form a subangular shoulder, a feature which may be sexual. The base of the body whorl is bounded by a pronounced spiral sulcus which extends from the middle of the inner lip to the margin on the inner side of the outer terminus of the canal. Body whorl ornamented with 12 narrow, square-topped spiral ribs; the interspace between the two upper spirals is deeper and much wider than the other interspaces, which range in width from a little narrower to a little wider than the spirals; crossing the spirals are numerous rather closely spaced axial ribs which are a little less prominent than the spirals; the intersections of the spirals and axials are marked by squarish nodes. Four or five of the spirals are exposed on the penultimate whorl. Aperture elongate-ovate with a distinct anal notch and a short deep canal; upper edge of canal bordered by a narrow, prominent fold. Outer lip broadly arched and notched at the intersection of the ribs; inner lip broadly excavated, and forming a thin callus on the base of the shell. False umbilicus deep above, flaring out rather broadly below, bordered on the columellar side by a narrow, sharp ridge, and on the other side by a plumply rounded, twisted ridge; both this ridge and the inner surface of the umbilicus are spirally striated. Dimensions of the holotype: Height 19 mm., diameter 12.5 mm. The volutions of this varietal form are a little more plumply rounded, and the upper part of the body whorl exhibits a very much less pronounced shoulder than does the typical Mor ea marylarulica Gardner. The sculpture is much finer than that of Al. caizcella.ria and its varieties. Cossmann::s3 has proposed the sub­generic name Pseudomorea, with Morea mar_l·/andica Gardner as type~ but a careful comparison of the Maryland species with Morea cancellaria fails to reveal differ­ 3b3Cossmann, 'f.. Es~a is Palc'.·oc. Comp., Liv. 13, p. 265, 1925. ences that would seem to justify the erec· tion of the subgenus. Types.-Holotype, U.S.N.M. no. 77025; 2 unfigured paralypes, U.S.N.M. no. 20916; 1 unfigured paratype, U.S.N.M. no. 77026. D£stribution in Texas.-Navarro group, Neylandville marl: '( ~~ mile north of Cooper (4064). Navarro group, Nacatoch sand: North edge of Corsicana (518, holotype and 2 paratypes) ; vicinity of Corsicana (763, loc. of 1 paratype) ; vicinity of Kaufman (761). Ran.ge.-Questionably from the Ney­landville marl upward into the Nacatoch sand of the Navarro group. MOREA MARYLANDICA LANGUIDA Stephenson, n.var. Pl. 61, figs. 3, 4 This variety resemble~ the species marylandica but has 9 instead of 11 spiral ribs, and has a decidedly more drooping shoulder, with scarcely a suggestion of a shoulder angle; these features produce a relatively coarser sculpture and a more slender contour. The shoulder of M. marylandica bella is narrower and less drooping and the sculpture is finer, the spiral ribs numbering 12. Dimensions of the incomplete holotype: Height 14.4+ mm., diameter 9.7 mm. Types.-Holotype, U.S.N.M. no. 77027; 1 unfigured paratype, U.S.N.M. no. 77028. Distribution in Texas.-Navarro group, Nacatoch sand: 4 miles north of Corsi· cana (17366). Family BUCCINIDAE? Genus SEMINOLA Wade 1917. Seminola Wade, Acad. Nat. Sci. Phila· delphia Proc., vol. 69, p. 290. 1920. Ripleya Cossmann, Re\'Ue g·eologie annee 1, no. 9, p. 376. 1926. Seminola Wade, U.S.Geol. Survey Prof. Paper 137, p. 144. Type species.-Seminola crassa Wade. If the recommendation of the Inter· national Commission of Zoological No· menclature is to be followed Wade is ' within his rights in retainincr the name Seminola, since the name with which this one is supposed to he synonomous is Seminolus. Invertebrate Fossils of the Navarro Group The genus is represented in the Navarro group by two species, S. crassa Wade, from the Nacatoch sand, and S. sp. from the Exogyra cancellata zone. Wade described two species, S. crassa and S. solida, from Coon Creek, Tennessee. One or two un­described species are known in the Ripley formation in Mississippi, and at least one species in the upper part of the Ripley formation near Eufaula, Alabama. Two species, S. globosa (Gabb) and S. green­ensis Stephenson,38·1 have been recorded from the Snow Hill marl member of the Black Creek formation, North Carolina. F asciolaria crassicosta Gabb,385 the type of which is a small crushed shell in the col­lection of the Academy of Natural Sciences of Philadelphia, has the form and the basal groove of Seminola and appears to belong to that genus. SEMINOLA CRASSA Wade Pl. 63, figs. 1-4 1917. Seminola crassa Wade, Acad. Nat. Sci. Philadelphia Proc., vol. 69, p. 291, pl. 19, figs. 6, 7. 1918. Seminola crassa Wade. Cossmann, Revue critique paleozoologie annee 22, nos. 1-2, p. 21. 1926. Seminola crassa Wade, U.S. Geol. Survey Prof. Paper 137, p. 145, pl. 50, figs. 9-12. Shell large, thick, semiglobose. Apical angle about 68 degrees; spiral angle in­creasing below to 85 or 90 degrees in medium stages, decreasing again to 65 or 70 degrees in adults where the body whorl begins to droop on the shoulder. Whorls 5 or 6, increasing rapidly in size, plumply rounded on the sides, with a pronounced shoulder above. Body whorl moderately elongated, rounding down broadly to a deeply impressed spiral sulcus at the base; the shoulder on the body whorl tends to droop and smooth off toward the aperture on adults. The suture is undulating and in young stages is closely appressed and moderately impressed; in later stages it tends to become less closely impressed and in some individuals opens out markedly. Protoconch not preserved hut evidently very small. The surface sculpture is ..Stephenson, L. W ., North Carolina Geol. and Econ. Survey, vol. 5, pp. 375-376, pl. 93, figs. 8-11, 1923. llllG&bb, W. M., Acad. Nat. Sci. Philadelphia Proc., vol. 28, p. 282, 1876. elaborate and markedly variable on dif­ferent individuals referred to the species. On the spire and the posterior part of the body whorl the dominant characters are the strong, coarse axial undulations which number about 12 on each whorl; pos­teriorly each rib is swollen into a coarse, node-like protuberance, the series of which produces the shoulder of the shell; posteriorly toward the suture the axials bend forward and tend to smooth off into a thickened, undulating, narrow collar which closely borders the suture; on this collar are 2 or 3 small obscure spirals. On the body whorl the coarse axials fade out less than halfway to the basal sinus, and on some large shells show a tendency to fade out toward the aperture. On the younger stages the conspicuous spiral sculpture con:;i~ts of moderately strong, squarish-topped ribs, generally narrower than the inters paces; these ribs override the axials without diminution in strength; 7 or 8 spirals are exposed on the penultimate whorl. On the body whorl of adults the interspaces tend to widen out and small secondary ribs appear be­tween the primaries, but this feature is irregular and variable on different in­dividuals; on some shells the secondaries become as strong as the primaries before reaching the lip. The surface is further covered with numerous more or less ob­scure, fine spiral threads which cover both the spiral ribs and interspaces. Aperture elongate-subovate, with a pronounced anal channel, and with a short, deep, moderately wide twisted anterior canal. Outer lip thin below and thin or thick above, de­pending on its relation to the coarse axials, crenulated on the inner margin; inner Iip broadly excavated, becoming thickly cal­lused in adults. Umbilical fissure shallow. The area between the umbilical fissure and the spiral sulcus at the base of the body whorl is a broad, nearly flat-topped twisted ridge, crossed by rugose incrementals; on young shells this area is covered with 7 or 8 low spiral ridges. The columella bears a pronounced, round-crested oblique fold below, which borders the upper margin of the anterior canal. Dimensions of the incomplete, nearIy adult shell shown in plate 63, figure 1: Height 77 + mm., diameter 56 mm. Di­mensions of a young shell (pl. 63, figs. The University of Texas Publication No. 4101 3, 4) whose apex is broken away: Height 27+ mm., diameter 21 mm. The largest shell in the collection is 87+ mm. high and 58 mm. in diameter. The Texas shells referred to this species, about 16 individuals from three localities, show considerable variation in form, orna­mentation, and closeness of coiling, and in this respect they agree with the shells from the type locality at Coon Creek, Tennessee. One adult shell from near Corsicana, Navarro County (763), exhibits a deep, wide sutural channel on the body whorl and an obscure development of shoulder nodes on the axials. Several young shells in the same lot are a little more finely sculptured than the shells of the same stage from the type locality, and they also show drooping shoulders. In view of the known individual variation within the species it seems best at present to refer these shells to Seminola crassa, but a better suite of specimens might justify their separation as a distinct variety. Types.-Holotype and paratype, U.S.N. M. no. 32911. Three plesiotypes from Texas, U.S.N.M. no. 77029. Distribution in Texas.-Navarro group, N acatoch sand: Vicinity of Chatfield ( 762, loc. of 3 plesiotypes) ; ?21/2 miles north of Corsicana (14114); ?vicinity of Corsi· cana (763). Outside distribution.-Tennessee: Coon Creek tongue of Ripley formation at Coon Creek, McNairy County (holotype and paratype). Range.-The species appears to be re­stricted to the lower half of the Exogyra costata zone of the Gulf region. SEMINOLA? sp. Pl. 62, figs. 6, 7 One incomplete body whorl of a small, probably juvenile, shell of Seminola, was obtained from the Neylandville marl on the Corsicana road, 21h miles north of Corbet, Navarro County (16170). The body whorl indicates a much more slender form than that of S. crassa Wade. In pro­file the body is broadly and acentrically rounded, the greatest inflation being above the midheight of the whorl; the surface, however, droops away from the suture with only an obscurely developed shoulder; a shallow, spiral sulcus on the upper part of the whorl produces a narrow, obscure collar. The spiral sulcus at the base of the body, which characterizes the genus, is sharpIy incised. The axials, though similar to those of S. crassa, lack the shoulder nodes, and extend down over the body nearly to the basal sulcus. The spirals are similar to those of S. crassa, but even at this apparently young stage they alternate in size except as noted below; the primary spirals are narrow, with a subsquarish top, and number about 13 on the body whorl; one small secondary spiral is present in each of the interspaces, with the exception of one on the most inflated part of the shell, and two higher on the shoulder. The aperture is elon­gated, with a shallow anal channel above, and a rather wide, deep, twisted, siphonal channel in front. Outer lip thin and cren· ulated on its inner margin; inner lip poorly preserved but apparently broadly excavated and thinly callused. Anterior fasciole broad! y rounded and rather ob­scure! y striated. Dimensions of the one incomplete shell: Height 9+ mm., diam­eter 5 mm. U.S.N.M. no. 77030. SEMINOLA sp. An internal mold belonging to Seminola, from the Kemp clay of the Navarro group, in a ditch along a public road 2 7/8 miles west-southwest of Staples, Guadalupe County (10878), is too poorly preserved for specific identification, but it shows the characteristic spiral sulcus at the base of the body whorl; numerous short axials ornament the upper part of the body whorl and the penultimate whorl. U.S.N.M. no. 77031. Genus HYDROTRIBULUS Wade HYDROTRIBULUS ASPER Stephenson, n.sp. Pl. 63, figs. 9, 10 Shell large, thick, rugged. Spire mod­erately high; the holotype is slightly de­formed mechanically but the spiral angle appears to be 55 or 60 degrees. The protoconch and about two of the succeed­ing whorls are broken away on the holo· type. Whorls 4 (estimated) , increasing rapidly in size; shoulder sloping, broadly excavated, forming a marked angle with the side below. Suture undulating, closely Invertebrate Fossils of the Navarro Group appressed, deeply impressed. Periphery scarcely suhangular; below the periphery the base becomes rather sharply con­stricted, hut rounds broadly into the canal below. The surface sculpture is coarse and vigorous. The axials are broad and round-crested, hut are very irregular in width especially on the body whorl; the interspaces are also very irregular in width, ranging from narrower to wider than the axials; the axials number 15 or 16 on the body whorl and on the penultimate whorl; each axial is coarsely nodose on the shoulder angle, hut becomes very faint where it crosses the shoulder above; both the axials and the growth lines bend strongly forward as they cross the shoulder to the suture; the axials extend well down over the base, fading out gradually as they reach the upper end of the anterior canal; toward the outer lip of the ho lo type the axial sculpture passes into a broad band marked by vigorous growth lamellae. The spiral sculpture consists of faintly bifid, squarish-topped ribs of only mod­erate strength, which override the axials and which are separated by much wider interspaces; a small secondary rib appears in one of the interspaces on the base of the type; 12 or 13 primary spirals appear on the body whorl, the four uppermost of which are exposed above the anterior suture on the penultimate whorl; very fine, ob­scure spiral lines appear over most of the shell. Aperture broadly subovate; anal canal shallow, bordered in front by a broad, low, obscure ridge; anterior canal deep, rather narrow, strongly twisted. Outer lip thick, coarsely lamellose; inner lip broadly ex­cavated, forming a thick polished callus over the base and columella, but thinning out abruptly in front. In the adult a prominent oblique fold borders the an­terior canal near the aperture, but this fold becomes less prominent as it passes back into the shell. Umbilical fissure glazed over, hut reflected as a shallow de­pression. Dimensions of the incomplete holotype: Height 67+ mm., diameter 47 mm. On the available material both the apex and the anterior canal are incomplete. Compared with H. nodosw Wade,886 this -Wade, Bruce, U. S. Geol. Suney Prof. Paper 137, p. 147, pl. 51, &p. 6, 7, 1926. species is much larger and has a pro­portionately higher spire and longer body whorl; the sculpture is also much less nodose at the intersections of the axial and spiral ribs. Types.-Holotype, U.S.N.M. no. 77032; 2 unfigured paratypes, U .S.N .M. no. 77033. Distribution in T exas.-Navarro group, Kemp clay: Branch 61;2 miles southwest of Currie (14139, 17377; type loc.); ?west of Zuehl (7720, 7721). Genus TRYONIA Stephenson, n.1ren. Type species.-Tryonia valida Stephenson. Etymology.-In honor of the distinguished conch­ ologist, George W. Tryon, Jr. Shell large, thick, rugged. Spiral angle 65 to 70 degrees. Height of spire less than the length of the aperture. Suture deeply impressed. Whorls 5 or 6, rapidly increasing in size, each with a narrow, but conspicuous squarish shoulder, and a tumid, rugose collar; sides of whorls broadly convex, subvertical; body whorl broadly rounded on the periphery, broad Iy excavated at the base. Axials rather sub­dued, irregular and numerous; they are noded at the shoulder angle and cross the shoulder to the suture in an obscure and irregular fashion; they become weaker downward and die out on the lower slope of the base. The surf ace of the body whorl from the shoulder angle downward to the base bears 10 or 11 strong, squarish. crested spirals, separated by interspaces of equal or greater width; several narrow, obscure spirals appear on the anterior canal. The growth lines are vigorous, and indicate a narrow, shallow notch at the shoulder angle; they bend strong Iy for­ward and cross the shoulder to the suture in a sinuous manner. Aperture lenticular, with a deep, acute anal sinus at the rear and a short, profound, anterior canal, bent strongly to the observer's left. The inner lip is broadly excavated centrally, and forms a thin callus over the middle and lower parietal wall and a thick ridge of callus just below the anal canal. Columella sturdy, twisted, broadly swollen at the upper margin of the anterior canal. The University of Texas Publication No. 4101 This genus appears to have a family relationship with H ydrotribulus W ade387 and Stantonella Wade.388 TRYONIA VALIDA Stephenson, n.sp. PL 62, figs. 8, 9 Shell large, thick, rugged. Protoconch and 2 or 3 apical whorls broken away. Spiral angle about 67 degrees. Whorls 5 or 6, the body whorl large and notice­ably longer than the height of the spire. The body whorl exhibits a narrow, squar­ish shouider, surmounted by a broad, sub­vertical, tumid, rugose collar, and these features extend with gradually lessening distinctness to the apex. Suture deeply impressed. In contour the body whorl is subvertical above just below the shoulder and rounds down very broadly to the broadly excavated base. Axials nonprominent and irregular in strength~ especially on the body whorl; they bear dull, elongated nodes at the shoulder angle and cross the shoulder above as obscure, low ridges of irregular strength; the axials become gradually weaker as they pass from the shoulder angle down over the base and practically disappear as they reach the bottom of the basal excavation; the axials number 20 on the body whorl, 18 on the penultimate, and 15 on the antepenultimate. From the shoulder angle down to the base the body whorl bears 10 or 11 strong, squarish-topped spirals, sep­arated by interspaces of equal or greater width, and several narrow, obscure spirals appear on the anterior canal; the spirals override the axials; 4 of the spirals are exposed on the penultimate whorl; spirals are wanting on the shoulder and collar. The vigorous growth lines cross the body whorl in a broad curve convex toward the aperture but bend sharply forward at the shoulder angle and cross the shoulder and collar in a sinuous trend; they indicate a shallow, narrow notch at the intersection of the shoulder angle with the outer lip. The aperture is lenticular and ends pos­teriori y in a deep, narrow anal canal; anteriorly the aperture is extended in a short, profound canal of moderate width 387Wa miles N. 20° "\\l. of Tona siding, in Hunt County ( 15545, U.S.N.M. no. 77080); it does not show the sculpture. A fragment (pl. 66, fig. 1) consisting of the well preserved protoconch and :1Y2 whorls of the spire of Omopsis? was ob­tained in the Kemp clay on Colorado Hiver at W,.ebberville, TraYis County (7601). The protoconch is a small, smooth conical shell of 3 volutions having an apical angle of about 55 degrees. The larger whorls of the spire present 12 strong axials similar to those of Ornopsis; these are reduced to 10 or 11 on the ~maller whorls. The spiral sculpture is finer than that of the other Texas species of the genus, but resembles that of 0. digressa \\1ade3 us from Coon Creek, Tennessee. The spirals increase in num­bPr from the smaller to the larger whorls, the new ones first appearing as secondaries between the primaries, but gradually in­creasing in size until they become as large as the primaries. On the largest whorl 3!•~Wad1', Brue•'. i-. S. Gl'ol. Survey Prof. Paper 137, p. L!7, pl. t:i. fig5. 3, 1, 19:.:!6. ] g or 20 spirals can be counted between the sutures. U.S.N.M. no. 77081. Genus REMERA Stephenson, n.gen. Type spcci{'~.---Rcmcra 111icrostriata Stephenson. Etymology.-By ana~ram from reamer. Gender, feminine. This new genus is characterized by an elongated, turreted spire, with an aperture shorter than the spire. The axials are numerous, nearly direct on the whorls of the spire, becoming gently sinuous with a broad curve convex toward the front on the base of the body whorl. The spirals are numerous and subdued; they override the axials on whose crests they become weaker. The aperture is elongated, arntely angular at the rear, and extends anteriorly into a siphonal canal of mod· erate length. The columella is without folds. There is no indication of an ex· panded lip, as in Anchura, to which genus Johnson,3 tni Wade·lllo and · other authors haYe pro'7isionally assigned closely re­lated shells of this kind. The protoconch is not preserved on the Texas material, but among 17 unnamed shells of this genus, probably represent· ing 2 or more species, in the Wade col­lection from Coon Creek, Tennessee, one young shell has the protoconch nearly perfect I y preserved; it is a small, smooth, rather high, trochoid shell of 21h volu· tions. REMERA MICROSTRIATA Stephenson, n.sp. Pl. 65, figs. 3, 4 Shell small, turreted, slender, with spiral angle of about 20 degrees. Proto· conch not preserved. Whorls 9 ( esti· mated), very broadly rounded to nearly straight on the sides. Suture moderately impressed, rather loosely compressed. Body whorl elongated, very broadly rounded from the suture above to the broadly excavated base below. The shell is ornamented with numerous, nearly di· reel or broadly curved, narrow axials, sub· angular to sharply rounded on the crests, separated by wider interspaces. On the 309Johnson, C. W., Aca spt>cit>~.-Fulgerra rcnusta Stepht>m•on. Etymology.-By anagram from graccful. Genxrarntc>d, stec>ply inclined; shoulder angle broadly obtu~e and form­ing the inflated part of the whorl~ of the spire; periphery broadly rounded, slop­ing gently to a broadlv rounded basal excarntion: canal straight. Each of the earlier whorls bears fr~m 16 to 20 axials of moderate strength, rounded on the crest: they trend upward and backward, bc>nding forward again on the shoulder; on the larger whorls the axials become strongly oblique, more widely and ir­regularly spaced, and tend to become obscure; on the body whorl the axials are present only on the shoulder and are irregular in strength of development. The growth lines on the body whorl curve strongly backward from below upward to and a little beyond the shoulder angle where they curve sharply forward, thus marking the successive growth stages of the anal notch. Very fine obscure spiral threads are present, strongest on the base of the bodv whorl and on the shoulder, absent or .dimly discernible on the in­flated part of the whorls. The individuals referred to this species show considerable range in the strength of development of the sculpture. Aperture elongated, sharp]y angular at the rear, narrowly channelled in front. Outer lip broadly arched, strongly notched just above the shoulder angle. Inner lip broadly excavated and forming a thin callus on the parietal wall. Columella straight, smooth. Dimensions of the holotype, which is slightly broken away at both extremities: Height 19.5 + mm., diameter 8.5 mm. Types.-Holotype, U.S.N.l\L no. 77156; ] unfigured paratype, U.S.~.l\L no. 77157. :\"amed in honor of the Hon. Richard B. Hubbard, Governor of Texas, 1877-1379. Distribution in Texas.-l\avarro group, ~acatoch sand: 1'orth edge of Corsicana t51B, type loc.): vicinity of Corsicana (763) ; vicinity of Kaufman (761); ?field 2 miles southwest of Kaufman (7547). LUTEMA MUNDA Stephenson, n.sp. Pl. 71, figs 18, 19 This species is smilar in form to Lutema sim ponsensis but is more slender and has coarser axial ornamentation. Spiral angle about 32 degrees. The axials are oblique and strongly developed on the shoulder auµ:lc of the body whorl, hut die out rather quickl~· both on the ~houlder above and on the body lwlow: they number 13 on the body ,~horl, 14 on the penultimate whorl, ~nd 16 on each of the next two smaller whorls. Spiral ornamentation is yery faint on the inflated part of the whorls, but becomes distinct on the shoulder, on the base of the body whorl, and on the canal; the spirals consist of low, flat, narrow ribs, separated by very narrow incised lines. The anal notch is sharply developed. Dimensions of the holotype, which is slightly broken on each extremity: Hdght 13 + mm., diameter 5 mm. Holotype.--U.S.N.M. no. 77158. Distribution in Texas.--Navarro group, Nacatoch sand: Vicinity of Kaufman (761). LUTEMA GENICULATA Stephenson, n.sp. Pl. 71, figs. 20, 21 This species has the general form of the three preceding species except that it is less slender and more inflated in the body whorl than any of them. The spiral angle is 42 degrees. The axials are oblique, short and stout, and on the shoulder angle of the larger whorls are developed into rather conspicuous, dull nodes; the axials number about 13 on each whorl. The shoulder is covered with fine, fairly dis· tinct spirals, and the third interspace be· low the suture forms a wider and deeper furrow than the others; spirals are present though barely discernible on the inflated part of the body whorl; the basal slope and anterior canal are covered with low, relatively broad, flat-topped spirals sepa· rated by very narrow, shallow interspaces. The anal notch is moderate} y deep, its deepest part lying slightly above the shoulder angle. The shell exhibits faint, irregular spots, or mottling, suggestive of color markings; individually some of the better preserved of these marks consist of a center of dark gray, surrounded by a band of light gray, cream, or brown, outlined without by a narrow band of dark grtly. Invertebrate Fossils of the Navarro Group Dimensions of the incomplete holotype: Height 11 + mm., diameter 6 mm. Holotype.-U.S.N.M. no. 77159. Distribution in Texas.-Navarro group, Nacatoch sand: Vicinity of Kaufman (761). LUTEMA sp. Pl. 71, fig. 26 Incomplete internal and external molds of one specimen of Lutema found in the Kemp clay of the Navarro group at the north corner of the John A. Thompson estate, 1500 feet east of the west line of the Wm. Fisher Survey, about 3.5 miles northwest of Bazette, Navarro County (12922), exhibit numerous sharply de­veloped axial ribs which tend to fade out on the body whorl, and a moderately deep anal sinus, the inner end of which is sharply rounded and lies just above the shoulder angle. The shoulder is broadly concave; on the earlier whorls it is crossed by the recurved axials, but on the body whorl it becomes smooth with the excep­tion of the growth lines. U .S.N .M. no. 77160. Genus BERETRA Stephenson, n.sen. Type species.-Beretra firma Stephenson, n.sp. Etymology.-By anagram from terebra (Latin), a gimlet. Gender, feminine. Shell of medium size, thick, turreted. Spire about as high as length of aperture; spiral angle 25 to 30 degrees. Whorls 7 or 8. Protoconch apparently small, smooth, rather high naticoid. Axial sculpture strong; spiral sculpture fine and weak. Anal sinus rather narrow and of medium depth. A tumid collar above the sinus is coarsely noded. Body whorl only moderately inflated, periphery broadly rounded, base broadly excavated. Aperture elongate-lanceolate; anterior canal long, narrow, nearly straight; anal notch of medium depth, rather sharply rounded at inner end. Columella smooth, straight. Species which should be ref erred to this genus include: Turris ripleyana Conrad from the upper part of the Ripley forma­ tion of Mississippi; Surcula amica Gardner from the Monmouth formation of Maryland; and Turricula ripleyana (Con­rad), Turricula gracilis Wade, and Tur­ricula amica (Gardner) of Wade, from the Coon Creek tongue of the Ripley formation, in Tennessee. (See references on p. 376.) BERETRA FIRMA Stephenson, n.sp. Pl. 72, figs. 13, 14 Shell of medium size, thick, turreted. Spire about as high as length of aper­ture; spiral angle about 25 degrees. Protoconch as seen incompletely preserved in one of the paratypes, apparently small, smooth, rather high naticoid. Whorls 7 or 8, closely appressed. Suture not deeply impressed, undulating over the axials. Body whorl moderately inflated; anal sinus of medium width and depth, bor­dered above by a tumid, coarsely noded collar, the nodes corresponding to the axials below; shoulder angle scarcely defined; periphery broadly rounded; base broadly excavated. Axials on body whorl strong, sharply rounded on the crests, obscurely noded on upper ends, fading out low down on base; axial sculpture ex­tending with only slightly diminishing strength to the apex; the axials number 16 on the body whorl, 15 on the penul­timate whorl, and 13 on both the ante­penultimate and the next earlier whorl. The spiral sculpture consists of numerous, rather weak ribs, strongest and coarsest on the base of the body whorl, finest on the anterior canal, and weakest on the most inflated part of the body whorl; the spirals increase somewhat in strength and sharpness toward the apex. Aperture greatly elongated, angular at the rear, produced anterior1y into a long narrow straight canal. Outer Iip broken, but obviously very broadly arched; anal notch narrow, of moderate depth, and broadly rounded at the inner end. Inner lip broadly excavated and forming a thick callus which completely covers the sculp­ture on the parietal wall. Dimensions of the incomplete holotype: Height so+ mm., diameter 15 mm. Compared with this species, Beretra ripleyana (Conrad) 438 from the Owl Creek '38Conrad, T. A., Acad. Nat. Sci. Philadelphia Jour., 2d ser., vol. 3, p. 332, pl. 35, figs. 21 and 29(?), 1858. formation on Owl Creek, Tippah County, MississiJJpi, has more numerous axial ribs, and less sharply dcyclopt~d spiral ribs. Beretra am ica (Gardner) ;i:Hi from the Monmouth formation at Friendlv, Marv­land, has fewer ribs, and fewer ~nd mo~·e ~trongly developed spirals. Turrfrula a mica lGardner) of \-Vade,Ho although having an equal number of axial ribs, has fewer spirals, a narrower collar band, and a more sharply constricted base. of Wade441 Turricu1a ri pleymza lConrad) has fewer ribs, and much more strongly developed spiral sculpture. Both of Wade's species belong to Beretra. Types.-Holotype, U.S.N.M. no. 77161; 4 unfigured paratypes, U.S.N.M. no. 20941; 1 unfigured paratype, U.S.N.M. no. 77162; 1 unfigured paratype, U.S.N.M. no. 77163. Distribution in Texas.-Navarro group, Nacatoch sand: Vicinitv of Corsicana { 763, loc. of 2 paratypes) ; north edge of Corsicana ( 518, loc. of holotype and ·1 paratypes) ; 2V:2 miles north of Corsicana (14114): vicinity of Chatfield {762); vicinity of Terrell (U.S.N.M. no. 77164, replacing old no. 12246) . BERETRA CONTRACTA Stephenson, n.sp. Pl. 72, figs. 17, 18 This species is similar in general form to Beretra firma, but has a shorter body whorl, which is more sharply contracted at the base. Shell of medium size, thick. Spiral angle about 30 degrees. Protoconch not preserved. Whorls 6 or 7. Body whorl short, moderately inflated; anal sinus narrow, of medium depth, rounded on bottom; the collar above is wider than the sinus and is coarsely noded, the nodes corresponding to the axials; periphery broadly rounded; base strongly con­tracted. Axials ribs coarse, rounded on the crests, faintly noded at upper ends, extending well down into the basal con­striction; on the holotype the ribs number 12 on the body whorl, 11 on the penulti­mate whorl~ and 10 on the antepenultimate 43!'Gardnt'r. Julia A.. :\Iaryland Geo!. Survey, Upper Crrtact•ous I:.! 'ok l. p. -1:20, pl. 14, figs. 8, 9, 1916. 4 H 1WJd1·. Bruce, L. S. Geol. Sun ey Prof. Paper 137, p. 11:2. pl. 36. fi~s. 1, :.!, 19:26. HlWaJ,., Brut t'. up. cit., p. 111, pl. 36. fi~s. 6, 7. whorl; the axials continue strong to the apex. The spirals are narrow, weak to moderately strong, and are square-topped; th~y rnry in wirlth, ranging from narrower to wider than the interspaces, being nar· 1owest and closest in the anal sinus; they are coarsest and most wirlely spaced on the base of the body whorl, and are weak· est on the inflated part of the body whorl. The aperture is elongate-lanceolate, sharply acute at the rear and produced anteriorly in a long, narrow, straight, siphonal canal. Outer Ii p broadly arched, anal notch of medium depth and broadly rounded at inner end. Inner lip forming a thin callus over the parietal wall. Columella smooth, straight. Dimensions of the holotype, which is broken at the apex and slightly broken at the anterior end: Height 34+ mm., diameter 13 mm. The species bears a superficial re· semblance to Beretra firma, but has a more sharply contracted base, and coarser and more strongly developed spiral sculpture. Types.-Holotype, U.S.N.M. no. 77165; 2 unfigured paratypes, U.S.N.M. no. 77166. Distribution in Texas.-Navarro group, Nacatoch sand: Vicinity of Chatfield (762). BERETRA STRIATA Stephenson, n.sp. Pl. 72, figs. 15, 16 This incomplete shell is practically identical in size and form with Beretra contracta, but differs in ornamentation. The axial ribs, though of about the same number and thickness are less prominent; they are weakly noded at their upper ends, and are represented on the collar above the anal sinus by moderateI y prominent, broadly round-topped nodes. An im· portant difference between the two species is in the spiral ribbing. In striata these ribs, though not prominent, nevertheless are distinctly developed over all the sur· face except the collar. The body whorl be­tween the fasciole and the periphery is cov· ered with 10 or 12 low ribs that alternate in breadth, the wider ones being slightly the more prominent; the separating inter· spaces are narrower than the ribs, and on Invertebrate Fos-sils of the Navarro Group the whorls of the spire are little more than sharply incised striae. Eight or 9 ribs on the basal slope are wider, more prominent, and more widely spaced than the ones above. The anal sinus hears 5 small, narrow, closely spaced spirals. The growth lines indicate a narrow anal notch of moderate depth. The incomplete holotype measures: Height 26+ mm., diameter 13.5 mm. Holotype.-U.S.N.M. no. 77167. Distribution in Texas.-Navarro group, Kemp clay: 31h miles north-northwest of Bazette ( 17375). BERETRA ORNATULA Stephenson, n.sp. Pl. 72, figs. 9, 10 The incomplete holotype is the only available specimen. Shell proportionate! y small, turreted, with strong spiral and axial sculpture, the latter dominant. Spiral angle 30 degrees. Protoconch broken away. Whorls 7, strongly ap· pressed. Suture moderately impressed, wavy. Body whorl moderately inflated, broadly rounded on the periphery, sharply contracted at base. Axials thick, prominent, round-crested, numbering 12 on the body whorl, decreasing to 7 on the smallest whorl. On the body whorl the axials are obscurely noded on their upper ends just below a deep moderately wide anal sinus; the latter is bordered above by a prominent, strongly noded collar that is narrower than the sinus; the axials die out well down on the base; they continue prominent on the smaller whorls to the tip of the spire. Spirals of moderate strength, squarish-topped, averaging about as wide as the inters paces; they override the axials on whose crests they may he weak or partly worn away. On the body whorl the spirals number about 12 be­tween the lower edge of the anal sinus and the base, and are strongest on the basal slope; several weak, closely spaced spirals are present still lower on the shell; 4 or 5 of the upper spirals are exposed on the smaller whorls. The anal sinus bears 4 small, closely spaced spirals; the collar is without spirals except in places on its lower slope where one or two small weak ones appear. The growth lines in­dicate an anal notch of only moderate depth. The outer Iip is badly broken, and most of the si phonal canal is gone. The inner lip forms a thin callus and is broadly excavated above. The exposed portion ~f the columella is smooth. Dimensions of the incomplete holotype: Height 19+ mm., diameter 8 mm. The sharply developed spirals give to this shell a more strongly ornate appear­ance than that of the other recorded species. Holotype.--U.S.N.M. no. 77168. Distribution in Texas.-Navarro group, N acatoch sand: 4 miles north of Cor­sicana ( 1 7366) . BERETRA? ELONGATA Stephenson, n.sp. Pl. 72, figs. 11, 12 One specimen from the Corsicana marl has the general form of Beretra firma, ex­cept that the spire is higher, the anterior canal is longer, and the base is more sharply constricted. Although the speci­men is not well preserved, it exhibits the specific characters clearly enough for de­scription. Shell elongated, turreted. Spire shorter than length of aperture; spiral angle approximately 23 degrees. Proto­conch not preserved. Whorls 6 or 7. Body whorl moderately inflated, the max­imum inflation being about at the periph­ery; anal fasciole of medium depth and a little wider than the collar above it; collar with dull nodes corresponding to the axials; periphery broad I y rounded, base sharp I y constricted. Axials of somewhat unequal developm~nt, ranging from nar­row and sharply rounded to moderately wide and broadly rounded; they die out about midway of the base; axials 15 on body whorl, and 12 each on the penulti­mate and antepenultimate whorls; the axials continue well developed, though poorly preserved, on the earlier whorls. Spirals numerous, narrow and of unequal development; they are coarsest and most widely spaced on the base, very weak on the upper part of the body whorl, a little stronger on the penultimate whorl, and rather sharply developed and closely crowded on the antepenultimate whorl. The Unirersity of Te.tas Publication No. 4101 The apNture is about 33 mm. long in the holotyp~. the upper 16 mm. being broadh· and moderately arclwd~ and the anteril;r part forming. a long. narrow, straight si phonal canal. The anal notch as shown by the growth lines is of medium depth and rounded at the inner end. The inner lip is broadly excaYated aboYe; the callus is incompletely preserYed but rem­11ants on the upper half of the canal indicate a rather thick lawr. Dimensions of the h,olotype: Height 55 -l-mm.. diameter about 13 mm. Tl1is species is much more elongated than any of the other species referred to the genus Beretra. Holotype.-r.s.~.l\I. no. 77169. Distribution in Texas.-Navarro group, Corsicana marl: 1 3/ 10 miles north of MrQueeney l 763 7) . Genus FUSIMILIS Stephenson, n.gen. Type 5pel'ie~.-Fusimilis robustus Stephenson. Etymology.-Combination uf Fusus and similis. Shell of medium size, thick, robust. Spire a little shorter than length of aper­ture: spiral angle about 4 7 degrees at the tip. decreasing to about 35 degrees on the larger whorls. Whorls 7 or 8. Body whorl shorL inflated, strongly constricted at base: anterior canal long, narrow, slightly sinuous. Axial sculpture strong, "·ith 1rnmerous ribs. Spiral sculpture comparatin·ly weak or absent on the spire and upper part of the body whorl, but coarse on the base. Collar band strongly sculptured with nodes or coarse growth lamellae. ~ukh of outer lip broad, shal­low. and situated a little below a narrow ~inus bordering the collar on its lower ~ide. Columella smooth with the excep­tion of a low. narrow ridge bordering the upper edge of the siphonal canal. This genu5 is only proYisionally re­ferred tu the famih· Turritidae; the broad ~hallow notch whi~·h lies below the usual position of the anal notch on the repre­~entatin·s of this family may not Le a true anal notch. The shells which Kade4 ·called Turrz'.s L! pro.rim a and T. constricta belong to this H 2\\..iclt'. Brue•» L S. Geo!. Survey Prof. Paper 137, p I Ill. l'l. 35. ti~~. 11, I:?; pl. 36, figs. 5, 10, 19:!6, new genus; these two species may in reality represent two stages of growth of one ~pecies only. Drillia novemcost~ta Conrad·11 :i from tlw Owl Creek formation al Owl Creek, Tippah County, Mississippi, is a member of this genus, and Drillia? tip pan a Conrad may belong to it. FUSIMILIS ROBUSTUS Stephenson, n.sp. Pl. 72, figs. 21-23 Shell of medium size, thick, robust. Spire a little shorter than length of aper­ture; spiral angle about 4 7 degrees at the apex, decreasing to about 35 degrees on the larger whorls. Protoconch not pre· served. ·whorls 7 or 8, closely appressed. Suture moderately impressed, undulating over the axials. Body whorl most inflated a little abo,·e the periphery; collar rather wide and closely set with rounded nodes which correspond to the axials below; collar bordered below by a narrow sinus of medium depth; periphery broadly rounded; base deepI y excavated. Axials numerous, thick, closely set, rounded on the crests; on the body whorl the axials end abruptly below at the periphery and tend to e\'anesce toward the aperture on adults; the axials number 20 or 21 on the body whorl, 18 on the penultimate whorl, and 15 on the antepenultimate whorl; from below the axials first sweep upward and backward in a broad curve, then bend sharply forward above, ending abruptly at the sinus below the collar; the upper end of each axial is obscure!y noded; due to the sharp forward cun'e of the growth lines the collar node corresponding to a given axial is set forward to a position directly above the interspace in front of the axial; the axial sculpture continues strong on the whorls of the spire to the apex. Spiral sculpture is wanting on all the surface of the shell above the periph· ery of the body whorl; on the base of the body whorl are 5 or 6 rather coarse, rug· ged lirae, narrower than the interspaces; on the upper part of the canal are 5 or 6 much finer and more closely spaced lirae which on the holotype become zigzag in trend as they approach the aperture. U3Conrad, T. A.• A.cad. l\"at. Sci. Philadelphia Jour., 2d ser., vol. 3, p. 331, pl. 35, fig. 13, 1858. Invertebrate Fossils of the Navar.ro Group Aperture acutely angular at the rear, ex­tended anteriorly into a long, narrow, slightly sinuous canal. Outer Iip broken away, hut strongly arched at the main opening of the aperture, with, as shown by the growth lines, a very broad, shallow notch below the intersection of the collar sinus. Inner lip rather deeply excavated, forming a callus on the parietal wall, which is thin above and thicker below. The columella is smooth with the excep­tion of a narrow, nonprominent ridge bordering the upper edge of the siphonal canal. Dimensions of the incomplete holotype: Height 50 + mm., diameter 21 mm.; one of the paratypes is 60 +mm. high. Closely related species occur in the Owl Creek formation of Mississippi. Types.-Holotype, U.S.N.M. no. 77170; I figured paratype, U.S.N.M. no. 77171; I unfigured paratype, U .S.N .M. no. 77172. Distribution in Texas.-Navarro group, Nacatoch sand: Vicinity of Kaufman ( 761, loc. of holotype a~d 1 paratype) ; road 2 miles southwest of Kaufman ( 7546~ loc. of I paratype) . Genua REMNITA Stephenson, n.gen. Type species.-Turricula biacuminata Wade. Etymology.-By anagram from minaret. Gender, feminine. The following description is based on the holotype of Turricula biacuminata Wade. Shell of medium size, fusiform, slender. Spire turreted, with 9 or 10 whorls. Apical angle 25 degrees; this angle is variable on different species. Suture moderate} y impressed. Whorls broadly convex on the side, the larger ones having a flattened hand above bordering the suture; this hand develops into an increasingly excavated shoulder on the three largest whorls. Body whorl greatly elongated, constricted at the base. Shell covered with numerous, squarish spiral ribs which are irregularly undulating in trend. Axial sculpture feehly developed or wanting; on the larger whorls a few broad, obscure axial undulations may he present hut these die out posteriori y before reaching the antepenultimate whorl. Aperture greatly elongated with a narrow, acute anal canal at the rear, widest above the middle, gradually narrowing below and passing into a long, narrow anterior canal which becomes slightly bent near the tip; the aperture is approximately equal in length to the height of the spire, hut varies a little one way or the other on different species. Columella smooth. Outer lip not preserved hut a decided notch above the shoulder angle is indicated by the sharply deflected growth lines on the shoulder. Turricula faceolata Wade and T. anomalocostata Wade are members of this genus. Amuletum Stephenson is a closely related genus. REMNITA BIACUMINATA (Wade) Pl. 72, figs. 19, 20 1926. Turricula biacuminata Wade, U.S. Geol. Survey Prof. Paper 137, p. 112, pl. 36, figs. 13, 14. For a detailed description of this species, see Wade's paper cited above. The following description is based on the one available incomplete specimen from Texas. Shell as preserved small, turreted, with a spiral angle of 28 degrees, incom­plete at both ends, with 3¥2 whorls remain­ing. Whorls broadly rounded on the sides, modified by a flattened hand just below the suture. Suture moderately but sharply im­pressed. Body whorl broadly rounded on the side and base, becoming constricted below, and exhibiting a faint suggestion of coarse axial undulations on the most inflated part. The body whorl is or­namented with about 17 spirals of unequal strength and spacing as follows: 4 spirals on the inflated portion are moderateIy coarse and are separated by slight Iy wider interspaces; the 4 uppermost spirals are smaller and more closely crowded; 4 or 5 spirals on the base are of about equal size and are separated by interspaces of corresponding w i d t h ; the remaining spirals in the basal constriction are small and obscure; 7 or 8 spirals are exposed on the penultimate and antepenultimate whorls. The growth lines on the body whorl trend upward and backward in a broad curve to about the center of the flattened shoulder hand, thence bend sharply forward to the suture; this sharp The University of Texas Publication No. 4101 bend indicates the presence of a pro­nounced notch on the upper part of the outer lip. The aperture is not preserved but is obviously elongate-lanceolate with rm acute posterior angle. Dimensions of the incomplete figured ~pecrnwn: Height 10. 7 + mm., diameter 5 +mm. The identification with the Coon Creek ~pecies is made with a fair degree of C'onfidence, though perfect material might show differences. Types.-H o l o t y p e and paratype, U.S.N.M. no. 32857; from Coon Creek, McNairy County, Tennessee. One plesio­type from Texas, U.S.N.M. no. 77173. Distribution in T exas.-Navarro group, Nacatoch sand: 4 miles north of Corsicana (l 7366). Outside distribution.-Tennessee: Coon Creek tongue of Ripley formation. Range.--The type material came from the upper part of the Exogyra cancellata zone; the Texas specimen came from a ~lightly higher position. Order OPISTHOBRANCHIA Suborder TECTIBRANCHIAT A Family ACTEONIDAE Genus ACTEON Montfort Type species.-Voluta torn at i l is Gmelin. ( = Voluta tvmatilis Linne.) ACTEON? THROCKMORTONI Stephenson, n.sp. Pl. 72, figs. 5, 6 Shell small and of medium thickness. Spire low; spiral angle about 80 degrees. Protoconch broken away, but obviously very small. Whorls about 3, closely ap­pressed. Suture shallow. Body whorl proportionately very large, elongate, with a narrow shoulder of medium steepness, and an ill-defined, obtuse shoulder angle; body whorl very broadly rounded from shoulder angle to anterior terminus. Axial sculpture wanting. Spiral sculpture con­sisting of numerous, rather sharply in­cised, punctate lines of nearly uniform strength, separating flattish ribs of clif­fering widths: on the body whorl the ribs are narrower on the basal slope than they are midway of the height, but several of the ribs one-third the length of the body whorl below the suture are narrow and closely crowded; 4 or 5 of the ribs are exposed on the penultimate whorl. Aper­ture elongate, very narrow above, acutely angular at the rear, widening below, but sharply rounded at the anterior terminus. The anterior part of the body whorl is broken away~ but the outer lip is obviously broadly arched. Inner lip deeply ex­cavated about midway of the height; the parietal wall is covered nearly to the suture above with a thin wash of sub. transparent callus through which the un­derlying sculpture may be seen. The columella is short and twisted and bears a strong oblique fold. Dimensions of the incomplete holotype: Height 8 + mm., diameter 4 + mm. Compared with the genotype, Acteon tornatilis (Linne) , of the Recent seas of Europe, this species has a closely similar, strong columellar fold, but is smaller, has a more pronounced shoulder angle, and the whorls are more closely appressed. Holotype.-U.S.N.M. no. 77174. Named for the Hon. James W. Throckmorton, Governor of Texas, 1866-1867. Distribution in Texas.-Navarro group, Neylandville marl: 21;2 miles north of Corbet (16170). ACTEON? NITIDUS Stephenson, n.sp. Pl. 72, figs. 7, 8 Shell small, thick, plump. Spire short; spiral angle approximately 90 degrees at the apex, decreasing below. Protoconch not preserved. Whorls 4, closely ap· pressed, broadly rounded on the sides. Suture moderately impressed. Body whorl plump, regularly rounded from the suture above to the anterior terminus below. Axial sculpture wanting. The spiral sculp· ture consists of numerous sharply devel· oped, narrow, squarish-topped ribs, sepa­rated by interspaces of equal or narrower width; the spirals number about 30 on the body whorl where they are coarsest on the basal slope and on the upper part, and are finest on the most inflated part; 5 or 6 of the spirals are exposed on the penultimate whorl. The interspaces are partitioned off into small rectangular spaces by thin sharp growth lamellae Invertebrate Fossils of the Navarro Group which appear to slightly override the spirals. Aperture elongate, narrow above and sharply acute at the posterior ex­ tremity, wider below and sharply rounded at the anterior extremity. The outer Iip is broken, but is broadly arched and is probably finely crenulated within. Inner lip deeply excavated below the midheight and, though poorly preserved, it probably forms a thin callus on the lower part of the parietal wall. Columella short, slightly twisted, and set with a rather thick, rounded, oblique fold of moderate strength. Dimensions of the holotype: Height 12 mm., diameter 7.25 mm. The columellar fold on this species appears to he more like that on Acteon than it is like that on Troostella. Types.-Holotype, U.S.N.M. no. 77175; 1 unfigured paratype, U .S.N .M. no. 77176. Distribution in Texas.-Navarro group, Kemp clay: Near Deatsville (764, para­type; 14125, holotype). Genu& TROOSTELLA Wade 1926. Troostella Wade, U.S. Geol. Survey Prof. Paper 137, p. 103. Type species.-Troostella perimpressa WadP.. The Cretaceous species here referred to the genus Troostella are usually assigned to Acteon, which is based on Acteon tornatilis (Linne), a Recent species of European seas. Although the Recent and Cretaceous forms are closely allied, the latter possesses a longer columella, a much less prominent and less oblique columellar fold, and a deeper and more open suture. These differences, though not great, probably justify the recognition of a separate genus to hold the Cretaceous species. Species referred to Troostella, in addi­tion to the type species, are: Acteon sub­&trialus Wade,444 from Coon Creek, Ten­nessee; Troostella sublinearis Stephenson from the Nacatoch sand, Navarro County, Texas; and T.? brevis pira Stephenson, also from the Nacatoch sand. "'Wade, Bruce, U. S. Geol. Survey Prof. Paper 137, p. 102, pl. 33, 611. 10, 11, 1926. TROOSTELLA SUBLINEARIS Stephenson, n.sp. Pl. 72, figs. 1, 2 Shell of medium size and thickness, glazed; height about twice the diameter. Spire rather low, less than half as high as the length of the aperture; spiral angle about 70 degrees at the apex, decreasing to 65 degrees on the larger whorls of adults. Protoconch not preserved. Suture at the bottom of a narrow V-sha ped chan­nel. Whorls 5, broadly rounded on the side. Body whorl moderately plump, broadly and regularly rounded from suture to anterior terminus, with neither shoulder nor peripheral angle. Axial sculpture wanting. Growth lines fine and broadly convex in trend toward the aper­ture. Spiral sculpture consisting of nu­merous fine, slightly impressed, punctate lines of irregular strength and spacing; the lines are coarsest on the base below and just below the suture above; there is a tendency toward alternation of larg~r and smaller lines. Aperture elongate, narrow and acutely angular posteriorly, broader below but sharply rounded at the anterior extremity. Outer lip thin, broadly arched, faintly crenulated within. lnntr lip rather deeply excavated a little below the middle; parietal wall bare above, rather thickly callused over below. Colu­mella slightly twisted with one broad, low, rounded fold well above the extremity. Dimensions of the incomplete holotype: Height 18 + mm., diameter 10.5 mm. The type specimens of this species bear the label Solidula riddelli Shumard. The original d e s c r i p t i o n of Shumard's44 :i species fits this lot of shells in most re­spects, but the spiral striae are said to number only 9 or 10, whereas on Troostella sublinearis they are fully twice as numerous, if only the more sharply impressed striae are counted. As Shumard's types are lost and can not be compared with the specimens now under consideration, it seems best to treat the latter as a distinct species. "6Shumard, B. F., Boston Soc. Nat. Hist. Proc., vol. 8, p. 194, 1862. Thr Cnil·crsity of Tc.ras Publication No. 4101 Thf> gc>rwtypc> of Troostella. T. pcrim­pressa \\-ade.·Ht> is Iaqrn and plumpn than the-Texas specif's. and its spiral lint'~ an" nwre dPepl ~-impressed. though the~· arc> f pwer in numlwr and more irrc>gtdarh spared. Typrs.-HPlntype. LS."\.\I. no. 77177: 6 unfigured paratypes. CS."\.\I. no. 771 78. lh{\trihu tim1 in Texas.-"\aYarro group. "\acatorh sand: "\orth ed!:!e of Corsicana 1 .:118. . type Inc. I: Yicinit,~· of Chatfield 1762L Rane.:e.-l\.no"11 onh· from the "\aca­toch s~nd in \"arnrro County. A. doseh­related. if not identical. species occurs m the> \"acatoch sand of _-\rkansas. TROOSTELLA? BREVISPIRA Stephenson, n.sp. Pl. 72. fig~. 3. 4 Shell small. of medium thickness. Spire low: spiral angle about 95 degrees. Protororwh not presen·ed. Suture chan­nelled. Y-shaped in cross section. \\110rls 3 or -1. broadh-rounded on the side: body whorl moder~tely inflated. broadI y and regular!y rounded. Spir3l sculpture con­sisting of numerous slightly impressed punctatf' lines of unequal strength and spacing. but showing a tendency to alter­nate in size. _-\perture elongate. narrow aboY<.3 and sharply angular at the postc>rior c>nd. becoming: wide> open below: anterior end brokt>n awa~-. Outer lip thin. broadly arched. Inner lip moderate!~-excarnted ht>low tlw midheight: parietal wall hare ahon'. callusf>d oYer below. \"o colu­mPilar fold can he seen from the apt>rture. Dimensions of the incomplt>te holoty pe: Height 3 __:__ mm.. diameter 5 mm. Thi" species is smaller. shorter. and has a wider aperture than Troostella sub­linearis: the ~piral srnlpture is also pro­portionateIy fi n~r. The failure to S(,e a rnlunwllar fold at the aperture leaYes dnuht as to the assi?nment of the shell to Trooste!la. llolot_\pe.--C.S."\.\I. no. 77179. Distribution in Te.ras.-"\aYarro group. \"acatoch sand: "\orth edge of Corsicana 15W1. H·~w3.J.· . Rm.-.·. L ~. l;c . .J. ~llf\•"V rr.. i. P.1pcr 137. 1. 1•·~. 1'>:6. TROOSTELLA? sp. One imperfr~·t ~hell from the Kemp rlay, in a !!t1Ih-2 mile~ north-northwest of Dt>al~'. illt". ·TraYi~ County (l-tl28), has the !:!f'nera I form of Troosfrlla su blinearis, lllit is more> dongatt'd and compr<'ssed on thP side. perhaps mel·lrnnically so. There is a sli~ht su~~estion. though no certain indicati<.~n. of the beginning of a columnar fold at the aperture. The sculpture con· sists of numerous. sharply impressed, punctate. spiral lines. The suture is channelled as in r. SU blinearis. This is probabl~-a distinct species but is not well enough preserved to serYe as a type. Dimensions: Height 21 +mm., diameter 10 +mm. U.S.N.M. no. 77180. Genus NONACTEONINA Stephenson, n.gen. Type :-.pedes.--.Yo11actca11ina ~raphoidcs Stephen· son. Etymolop:y.-.Yon ~ not; Actco11i11a. Shell of medium size and thickne~s, Plongated. Spire high. but in the geno· t~·pe is less than two-fifths the total height of the shell. and has an apical angle of about -12 degrees. Protoconch small, smooth. coiled._ 21 ~ or 3 times. Whorls broadh-and ewnlY conwx on the side, closely. appressed.. Suture sharply but not deepl~-impressed. Body whorl elongated. broadly rounded, but slightly compressed on the side. Shoulder and peripheral angles wanting. Axial sculpture wanting. Spiral lines numerous, punctate. Aperture elongated~ narrow abow, acutely an!!ular at the rear. wide below, but sh;rply rounded at the anterior end. Outer lip thin. broadly arched, faintly crenulated within. Inner lip with a deep excaYation well below the middle, and formin!:! a callus onh-on the lower part of the Lparietal wall. Columella thin and twisted. with no eYidence of a fold on the aYailable specimens. An imperfect shell from Coon Creek, Tennesst"'e. which \Yade-H7 called Acteonina orientalis. appears to be a member of this new genus. Acteonina d"Orbigny is based on a Carboniferous species, Chemnitzia H;'"Wade. Brnu. l". s. Geol. Sur\(')' Prof. Paper 137, r. lO.t, rl. 3L tip:. s. 9, Ifl~6. Invertebrate Fossils of the Navarro Group carbonaria de Konick,448 which, judging from the original figure, is entirely dif­ferent in form, has a much lower spire, and cannot reasonably be regarded as con­generic with this Cretaceous species.449 An inner portion of the columella of the specimen described by Wade is exposed, and it bears no fold. The internal mold figured by W eller450 under the name Actaeon gabbana Whit­field, which is not the species described and figured by Whitfield, probably is a species of N onacteonina. NONACTEONINA GRAPHOIDES Stephenson, n.sp. Pl. 7 3, figs. 24, 25 Shell of medium size and thickness, elongated. The spire is high, hut is less than two-fifths the total height of the shell; spiral angle about 42 degrees at apex, decreasing somewhat below on the spire. Protoconch small, smooth, coiled 21h or 3 times. Whorls 5, broadly and evenly convex on the side, closely appressed. Suture sharply but not deeply impressed. Body whorl elongated, broadly rounded above and below, slightly compressed cen­trally; shoulder and peripheral angles wanting. Axial sculpture wanting. Trend of growth lines broadly convex toward the aperture. Spiral lines fine and numerous, punctate, coarsest on the basal slope and just below the suture; spiral lines some­what irregular with respect to strength and spacing, but showing a tendency to alter­nate between narrow, sharply incised chan­nels and very fine grooves; about a dozen of the stronger spiral grooves are exposed on the penultimate whor 1 and 8 or 9 on the antepenultimate whorl. One incom­plete specimen from near Chatfield, Na­varro County (14117), exhibits much more sharply incised, and more closely spaced spiral lines, than other specimens studied, and is questionably referred to this species. Aperture elongate, very narrow above, acutely angular at the rear, widening out below, but sharply rounded at the anterior extremity. Outer "'d'Orbigny, Alcide, Prod. Pal., vol. l, p. ll8, 1850. "'See also Stewart, Ralph B., Acad. Nat. Sci. Phil· adelphia Proc., vol. 78, p. 433, 1926. "°Weller, Stuart, Geo}. Survey New Jersey, Paleontology, •ol. 4, p. 807, pl. 99, figs. 78, 1907. lip rather thin, faintly crenulated within, broadly arched, but slightly subtruncated above the midheight. Inner lip strongly excavated well below the midheight; parietal wall bare above, call used over low down on the base. Columella thin and twisted with no evidence of a fold on any of the available specimens. Dimensions of the nearly complete holo­type: Height 23.5 +mm., diameter 9 mm. The holotype and 3 of the paratypes bear an original identification label, "Acteon linteus (Conrad)," but compar­ison with topotypes of Conrad's species shows that the Texas shells have a much higher spire, and apparently lack a columellar fold, and cannot be that species. Types.-Holotype, U.S.N.M. no. 77181; 3 unfigured paratypes, U.S.N.M. no. 20893; I unfigured paratype, U.S.N.M. no. 77182. Distribution in Texas.--Navarro group, Neylandville marl: 21h miles north of Corbet ( 17365) . Navarro group, Nacatoch sand: Vicinity of Chatfield (762, loc. of holotype); ?3/5 to 4/5 mile northeast of Chatfield (14117); north edge of Corsicana (518, loc. of paratypes) . NONACTEONINA DEFLEXA Stephenson, n.sp. Pl. 73, figs. 26, 27 Shell small, elongate, fullest below the midheight. Spire a little more than one­third the total height of the shell; spiral angle about 54 degrees near the apex, de­creasing markedly below. Protoconch broken away. Whorls 4 or 5, closely ap­pressed. Suture shallow but sharply im­pressed, curving obliquely downward as it approaches the aperture. Body whorl elongated, slightly flattened on the side, drooping noticeably toward the aperture. Axial sculpture wanting. Trend of growth lines very broadly convex toward the aperture, fullest below the midheight of the body whorl. Spiral grooves numerous, sharply impressed, punctate, somewhat ir­regularly spaced, with a decided tendency to alternation in strength on the lower two­thirds of the body whorl. Five or 6 grooves are exposed on the antepenulti­mate whorl, but owing to the downward The University of Texas Publicatfon No. 4101 trend of the suture the numlwr of exposed grooves inC'reases successiYelv to a maxi­mum of 10 on the larger . part of the penultimate whorl. Aperture greatly elongated, sharply acute above. widening out below, but sharply rounded at the anterior extremity. Outer lip thin. form­ing a very broad, slightly truncated curw. Inner lip forming a thin callus on the parietal wall, deeply and broadly ex­cavated on the lower part of the base. Columella thin and twisted. Dimensions of the slightly incomple~e holotype: Height 8.7 +mm., diameter 3.2 mm. The three incomplete, questionably identified specimens from near Chatfield (U.S.N.M. no. 21073) resemble this species, but they appear to be a little more slender, more flattened on the side, and have slightly finer spiral sculpture; they have the same drooping suture at the upper side of the body whorl. This species is much smaller than N. graphoides and is more slender and more flattened on the side of the body whorl. Types.-Holotype, U.S.N.M. no. 77183; one young incomplete paratype, U.S.N.M. no. 77184. Distribution in Texas.-Navarro group, Nacatoch sand: 4 miles north of Corsicana (17366, type loc.) ; ?vicinity of Chatfield (762). NONACTEONINA TENSA Stephenson, n.sp. Pl. 73, figs. 22, 23 Shell small. slender, of medium thick­ness. Spire high, slightly exceeding the length of the aperture; spiral angle about ~5 degrees at the apex, decreasing to about 25 degrees below on the largn whorls. Protoconch broken away. W'horls 5 or 6, closely appressed, broadly rounded on the sides. Suture shallow. Body whorl elongated. broadly and regularly rounded on the side. Spiral grooves on the body whorl sharp~ punctate, numbering about 4 to the millimeter: an occasional weak groove is intercalated between the others, becoming stronger tovrnrd the aperture; spacing of grooves somewhat irregular, being widest centrally and narrower above and below on the body whorl. Aperture Ion~. sharply acute above. widening out below, and sharply rounded at the anterior extremity. Outer lip thin; inner lip form. ing a thin callus. DimPnsions of holotype: Height 10 + mm., diameter ~.2 mm. The specit·s rPsem bl cs N. deflexa, but has a longt'r ank. Ten­IH_in its blunter apex and 'ssee. more closely appresst>d whorl'. The arnilable specimens are all smaller than ·wadt>"s holotype. and they appear to be a little more slender. The protoconch is not per­fect! y prt>serwd on any of the specimens. but it appears to be smal1. trochoid and the surreedin~ whorl of the main shell expands rapidly away from it. The spiral g:rooYes are deep. finely punrtate. and rnry considerably in number and sparing on different indiYiduals: theY are. how­eYer. more closely spared on the base than on th~ main surface aboYe. The two rolumellar folds are not perfectly pre­sern·re is a slight flattening of the side of the bod,-whorl. Dimensions of the holotYpe: Height about 7.5 mm.. diameter -t 1~1~11. Compared with the Yariety hebes. this rnriety is less blunt at the apex. and has a more slender profile: the ornamentation is similar in the two Yarieties. i:~-w~..: c_ B:..: :,,_ r_ :3. Ge,~1. S;.;:'c''. P~·-' '.. Plpc'r 13';', r. 1':13. ,-.:_ 3i, ~;5. 3_ 4, 19'.::6. Types.-Holotype. r.S.\".'!· n?. 77192; .--, unfigured paratypes. l .S.~.M. no. 77193. lhstrihution in Texas. ·\"ayarro group, '\acatoch ~ancl: Fit~ltl we~t of Kaufman 11 -H031: YicinitY of Chatfield ~ 762); % 1~1ile east of Cl~atfield 17571): 3 miles northeast of Corsicana I 95--!5) : 31 .~ miles north of Corsicana I 16168) : road 5 miles ~outh-soutlnn~st of Corsicana (7573, type loc. '1. TORNATELLAEA GRANDIS Stephenson, n.sp. Pl. 73. figs. 18, 19 Shell large as compared with other Cretaceous species. Height of spire a little less than length of the aperture; spiral angle about 70 de~rees at the apex, decreasing to about 50 degrees on the larger wl;orl~ below. Prot~conrh small, but._ poorl~-preserwd. Whorls 5, broadly rounded on the 5-ide~ dosely appressed. Suture mo~erately impre~sed. Body whorl broadh-and e\·enh-rounded near the aperture from the sut~re aboYe to the anterior extremity. Surface ornamented all oYer with . moderately impressed £rooYes. a little wider than the interYening ;quarish ribs: each grooYe is diYided into manY small. transwrse rectangles by thin axiai partitions which. on the smaller whorls. giw to the grooYes a punctate ap­pearance: about 20 groo\-es appear on the bodY whorl. and 7 or 8 are exposed on the . penultimate whorl: the groon.>s low on the base of the hodY whorl are nar­rower and more closely ~pared. Aperture elon£ate-suboYate. aruteh-angular at the 1t'i:H.... and sharply r~unded~ with a siphonal notch in front. Outer lip brokt>n. hut brnadh-arched. Inner lip deepl ~-exrarnted a . little below the mid­height. apparently not forming a callus on the parietal wall. Columella bearing 2 large. strong. moderately oblique folds. Dimensions of the slightly defective holotype: Height about 16 111111.~ diameter H.5 mm. This is the largest Cretaceous species known in the Coa$tal Plain. and is about equal in size to the genotype~ T omaJellaea be/la Conrad~ from the Eocene of .Ala­ bama. The apex of grandis is much less Invertebrate Fossils of the Navarro Group acute than that of bella which becomes increasingly more slender from the penul­ timate whorl backward, ending in a small, elevated protoconch; the spiral grooves of bella appear to be more deeply im­ pressed. Types.-Holotype, U.S.N.M. no. 77194; 2 unfigured paratypes, U.S.N.M. no. 77195. Distribution in Texas.-Navarro group, Kemp clay: Near Deatsville (14125, type loc.); ?Webberville (7601). Family RINGICULIDAE Genus RINGICULA Deshayes RINGICULA PULCHELLA Shumard Pl. 73, figs. 3-5 1861. Ringicula pulchella Shumard, Boston Soc. Nat. Hist. Proc., vol. 8, p. 192. 1926. Ringi,cula pzdchella Shumard. Wade, U.S. Geol. Survey Prof. Paper 137, p. 105, pl. 34, figs. 10, 11. Shumard described this species as fol­lows: Shell small, oblong oval; spire moderately elevated, conical, acute at tip, enlarging rather rapidly from apex, volutions five, rounded; last one large and ventricose; suture distinct, de­pressed; aperture narrow, curved, pointed above, gradually widening to the base; outer lip thick­ened, broad, acute above, prolonged upon the spire, inner edge strongly crenulated, outer surface [of lip] marked with distinct, longi­tudinal, and transverse lines, and presenting a finely cancellated appearance; columellar lip thickened and marked below with strong teeth. Surface with rather coarse, rounded revolving lines, of which there are about sixteen on the body volution; these are crossed by very fine, ~rowded striae of growth, which give to the intervals between the revolving lines a minute punctate appearance. Length, 0.26 inch; width, 0.2 inch; apical angle, 60°. Shumard's types are probably lost, but among the collections at the National Museum are 7 specimens from near Chat­field, the type locality, which are believed to belong to the species, and about 125 specimens have been collected near Cor­sicana. These collections reveal consid­erable individual variation in specific characters, but some specimens conform closely to the original description. Shum.ard's delineation of the species may he supplemented by the following notes. The angle of the spire near the apex varies on di:fferent shells from 60 to 73 degrees. The protoconch is small, smooth, conical, and coiled about l 1h times. The number of whorls in addition to the coils of the protoconch is 4 instead of 5, on even the largest shells. The sutures are closely appressed. The surface may be described more accurate! y as ornamented with spiral, flat-topped ribs separated by narrow punctate grooves; these ribs vary in number on different individuals from 12 to 21, but on many the number is 16; the ribs on the basal slope are generally narrower than those higher on the body whorl. The cancellated outer surface of the thick outer lip of adults is a striking feature of the shell; this sculp­ture is produced by the spiral grooves overriding the thick callus, crossed by coarse growth ridges; the thickened outer lip is prolonged upward across the penul­timate, and halfway across the antepenul­timate whorl. The thick callus forming the inner lip of the aperture presents curi­ous, irregular features which vary some­what in detail on different individuals, but which include from below upward: A narrow, prominent, oblique ridge bor­dering the narrow twisted anterior canal; just above this ridge is a profound, very oblique channel; next above is a prom­inent, very oblique columellar fold which is bifid at its outer end, but quick I y coalesces into a single fold as it passes inward; paralleling this fold above is a wider, less profound channel which is almost at right angles to the linear direc­tion of the columella; bordering this chan­nel above is a narrow, moderately prominent fold which at its outer end bends sharply upward and continues for 2 or 3 mm. as an irregular ridge of call us with a general vertical trend. The ridge just described forms the anterior side of the anal canal, the posterior side of which is formed by the upward prolongation of the thick outer Ii p. A very wide, curved, anterior fasciole, which forms the anterior end of the columella, is marked with 3 or 4 narrow, longitudinal ridges, and by numerous, more or less obscure, transverse striations. The University of Texas Publication No. 4101 Dimensions of the medium sized .neo­typc: Height 6.5 mm., diametf'r, includ­ing the thick outer Iip, 5 mm. The large~t sperimens do not exceed 9 mm. in height. The one beautifully preserved shell from Coon Creek, Tennessee, which Wade referred to this species, appears to be correctly identified. Types.-The whereabouts of Shumard's type material is unknown; presumably it is lost. The neotype is selected from seven specimens from near Chatfield, Navarro County, the type locality: Neo­type, U.S.N.M. no. 77196~ 5 typical examples, unfigured, U.S.N.M. no. 77197; 1 figured example, U.S.N.M. no. 77219. One hundred and twenty-five specimens, many of them better preserved than those from Chatfield, have been collected from near Corsicana in the same county (U.S.N.M. no. 20944). Distribution in Texas.--Navarro group, Nacatoch sand: Northeast of Quinlan (16162) ; vicinity of Chatfield (762, neotype and 5 typical examples) ; from loose pieces of rock in street at Chatfield ( 7568, 1 example figured) ; 3 miles north­east of Corsicana (9545) ; Watkins' place 3 miles north of Corsicana (9552) ~ 2 miles north of Corsicana (9553, 9554,) ; 2% miles north of Corsicana (14114) ; north edge of Corsicana (518) ; vicinity of Corsicana (763) ; road 5 miles south­southwest of Corsicana (7573) ; 4 milt's north of Corsicana (17366) ; 5 miles northeast of McClanahan (17371). Outside distribution.-Tennessee: Coon Creek tongue of Ripley formation. Mississippi: Ripley formation. Chattahoochee region (Alabama) : Up­per part of Ripley formation. Range.-In Texas the species has been recorded only from the Nacatoch sand. The occurrence of the species in the Coon Creek tongue in Tennessee indicates a slightly lower range there than the known range in Texas. There is no record of the species in the uppermost beds of the Exogrra costata zone. RINGICULA CULBERSONI Stephenson, n.sp. PI. 73, figs. I, 2 Shell large for the genus. Spire high, acute. Spiral angle about 55 degrees at the apex, increasing to 60 degrees on the larger whorls below. Protoconch small, conical, coiled 11,h or 2 times. Whorls S, dosdy appressed, broadly rounded on the side. expnndinp; rn pidly. Suture rather deeply impressed. Body whorl large, plump, evenly rounded in profile. The surfare is ornamented all over with nu. merous flat-topped ribs of irregular width, separated by narrow, shallow', square· bottomed, finely punctate grooves; 27 ribs appear on the body whorl of the holo· type, the widest, about midway of the height, being half a millimeter wide; 8 or 9 ribs are exposed on the penultimate whorl. Aperture rather widely open, elongate-subovate, increasing somewhat in width from above downward; the siphonal canal is short, twisted, and forms a narrow, deep notch on the front margin. The outer Ii p is broadly a;rched and thickened, and is prolonged about halfway across the penultimate whorl above, where it forms the inner side of the anal canal. The inner lip is rather thickly callused, is deeply excavated below, and bears 3 folds; the lower fold is narrow, prom· inent, moderate!y oblique and borders the anterior canal; the middle one is narrow, prominent and curved, becoming strongly oblique as it passes backward; the third one is narrow, weak, strongly oblique, and is high on the parietal wall; on well preserved shells a ridge of callus forms the outer edge of the inner lip, extending upward and slightly backward and be· coming at its upper end the outer side of the anal canal. The callus of the inner lip differs considerably in strength of development on different individuals, and is not well preserved on some specimens. Dimensions of the holotype: Height 13.9 mm., diameter 9.5 mm. This species has no rival in size among our Upper Cretaceous Ringiculas from the Coastal Plain. Types.-Holotype, U.S.N.M. no. 77198; 1 unfigured paratype, U.S.N.M. no. 21187; 3 unfigured paratypes, U.S.N.M. no. 77199. Named for the Hon. Charles A. Culberson, Governor of Texas, 1895-1899. Distribution in T exas.--Navarro forma· lion, Kemp clay: Near Deatsville (764, Invertebrate Fossils of the Navarro Group holotype and 1 paratype; 14125, 3 para­types). RINGICULA ANFRACTOLINEATA Stephenson, n.sp. Pl. 73, figs. 6, 7 Shell small, thin. Spire elevated, acu~e; spiral angle 70 degrees at the apex, m­creasing somew~at below. . Protoconch small, conical, coiled about twice. Suture sharply but not deeply impressed. Whorls three, closely appressed, broadly cu.rved on the sides. Body whorl proportionately large, broadIy and regularIy curved in profile. Surface of body whorl orna­mented with 15 closely spaced grooves, each of which is finely zigzag in trend, thus producing an elegantlx patterned surface; 6 grooves are exposed on the penultimate whorl. Aperture elongate, rather narrow, acutely angular at the pos­terior end widening somewhat anteriorly, ending i~ front in a relatively broad notch, overhanging a .little on ~he . outer side. Outer lip thick, long1tudmally striated, produced above a li~tle more than half way across the penultimate whor1; inner surface of outer lip transversely striated. The inner lip is deeply excavated below and forms a thick, irregular callus the upper part of which on the holotype has become peeled off and lost; the de­scription of this lip is based in part on the holotype and in part on the paratypes; a narrow sharply upraised fold borders the short, twisted, siphonal ~anal below; ab~ve this fold is a broad, oblique channel which is bordered above by another narrow prominent oblique fold, sometimes bifid; the second fold is bordered above on the parietal wall by a broad, shallow, oblique channel· from the outer end of this chan­nel ther~ extends upward a bifid ridge of callus which borders the outer side of the well developed anal canal. The anterior f~ciole, which in reality forms the an­terior prolongation of the call~s of the inner lip, is broad, strong Iy twisted and grooved near its outer boraer. . Dimensions of the holotype: Height about 4.75 mm., diameter 2.5 mm. This elegant and remarkably well _Pr~­served species is much smaller than Ringi­cula pulchella Shumard, and is character­ized by its exquisite surface pattern of zigzag lines. Types.-Holotype, U.S.N.M. no. 77200; 3 unfigured paratype~, U.S.N.M. no. 77201. Distribution in Texas.-Navarro group, Kemp clay: Webberville (7601, 3 para­types; 13910, holotype). RINGICULA SUFFLATA Stephenson, n.sp. Pl. 73, figs. 8, 9 Shell of medium size, plump. Spire low, conical; spiral angle about 85 de­grees. Protoconch small, appare~tly coiled 11;2 times. Whorls 3, expandmg rapidly, broadly curved on the sides. Suture moderately impressed, slightly channelled. Body whorl proportionately very large, plump, evenly rounded in profile. Surface of body whorl orna­mented with 17 sharply incised grooves which are finely zigzag in trend, and show some unevenness in spacing; 7 grooves are exposed on the penultimate whorl. Aperture elongate, moderately wide open, acutely angular at the rear, widest cen­trally and narrowing slightly at the front; anal canal wide and strongly developed, siphonal canal narrow, twisted and rat~er deep. Outer lip broadly arched, thick, prolonged posteriorly across the penult~­mate and nearly across the antepenulti­mate whorl, there forming the inner wall of the anal canal. Inner lip strongly ex­cavated below and forming a heavy, strongly differentiated callus; a narrow, sharply upraised oblique fold borders the anterior canal; on the lower part of the parietal wall is a still more prominent, more oblique fold separated from the lower fold by a profound, rather wide channel; beginning a little a~ove ~he second fold is a prominent, vertical, bifid ridge of cal~us which. extends upw~rd h~gh onto the spire, f ormmg the anterior side of the anal canal; behind the vertical ridge near its lower end is a weak transverse fold; anterior fasciole narrow, strongly curved. Dimensions of the holotype: Height 8 mm., diameter including the thickened lip 6.5 mm. This species has a lower spire and is more globose than any previo~sly de­scribed species in the Coastal Plam. Types.-Holotype, U.S.N.M. no. 77202; 2 unfigured paratypes, U.S.N.M. no. 77203. The Unirersity of Te.ras Publication No. 4101 _Distribution in Texas.-\"anuro group, Kemp clay: 3 mil~s S. ~~O.) \Y. of Thrall l 15537, holotype; 173 70, 2 paratypes). Unidentified species of RINGICULA Two small imperfectly preserYed speci­mens of Ringicula from the Corsicana marl. in a bluff on Onion Creek 21.:> . ' , .. miles west of old Garfield, TraYis County l 15532), can not be assigned to any de­scribed species. U.S.N.J\I. no. 7720-1. A badl\" crushed internal mold of a medium si~ed shell, with the spiral groo\·es impressed upon it. from the same forma­tion in a branch below the public road, 21 ~ miles north of Tona siding, in Hunt County l 155-161, is questionably referred to Ringicula. r.S.l\.M. no. 77205. Genus OLIGOPTYCHA Meek Type specie~-Actaevn concinnus Hall and ~leek ( == Cinulia ( Oligoptycha) cvncinna l Hall and ~feek J :\leek). The name Oligoptycha was proposed by ~Ieek4~'3 as one of three subgenera of Cinulia, of which Cinulia s.s. and Avellana were the other two subgenera. Oligo­ptycha differs sufficiently from either Cinulia or Avellana to justify its recog­nition as a separate genus, and has already been so recognized by Stewart.-!~,.i How­eYer, a careful comparison of the Cali­fornia shells in the l\ational l\Iuseum, labelled Cinulia obliqua Gabb, with ma­terial in the :Museum which was studied or figured by :\leek, shows that in the former the siphonal canal lies higher aboYe the anterior terminus of the aperture, and in addition to the strong fold aboYe the canal it has a weaker fold on the lower side of the canal: in the typical Oligoptycha the margin of the shell itself forms the lower margin of the canal. The California shell is doubtfully an Oligopt_rcha~ as Stewart considered it to be. Oligo pt_rdza is particubrly character· ized by one prominent fold at the base of the columella. This fold is so strongly -&:.S\ft't'k. F. B .. R.·pt. l'. S. G1·ul. Sur\·~y Tt•rr.. vol. 9, 1·p. :28.).:28 L rl. 31. fi~~ . 6 bis. :i b c. 1876. S1·t' .,)so: lb!l and \ft-ck. _-\m..-\oJ..\r:s and Sci. ~lcm., r.,>sttlll. \t•l. 5 \ n. ,;t'f. ·1. p. 3()0, pl. 3, fig . .t. 185.t; Coss· IJl;lnll. \I.. [.--.J :s r . .t1,·,1c. Comp .. \Ol. )\, no. l. p. L~l. 1895. " '"'~tt'\•.nt. R,;lp: i. .-\.-;i,), :\~t. Sci. Phi!JJelph:a Proc., ,,.J. 78. p. UtJ. l•l:.;ti. oblique that its outer end ascends instead of descends as is usual with such folds· ' the fold borders the upper side of a nar­row. deep siphonal canal, which also rises at its outer end. Although Meek men. tions onh one columellar fold, the re. moYal o( matrix from within one of the specimens handled by him re\'eals swell. ings on the parietal wall well back in the shell that may be the beginnings of two weak folds. The shells from Texas and Tennessee, described on fallowing pages as Oligo· ptycha am ericana ('\Vade) ~ exhibit such a close similarity to Oligoptycha concinna lHall and Meek) in form and sculpture, and in the character and trend of the basal columellar fold and the siphonal canal, that it seems reasonable to treat them as generically identical. Possible objections to this classification are 2 to 4 small folds on the parietal wall, and crenulations on the inner margin of the outer lip, of the Texas and Tennessee specimens, but in Yiew of the other similar features, the differences mentioned should perhaps he regarded as specific, or perhaps sectional, rather than generic. The genus Eriptycha, to which Wade questionably referred his species ameri­cana~ though similar in form, is quite dif. ferent from Oligoptycha in the character of its columellar folds and its siphonal canal. OLIGOPTYCHA AMERICANA (Wade)? Pl. 73, figs. 10, 11 1926. Eriptyclrn? americana Wade, LS. Geol. Suney Prof. Paper 137, p. 105, pl. 34, figs. 13, 14. Shell wry small, subglobose. Spire low, almost dome-shaped. Protoconch small and apparently coiled less than twice, with axis slightIy tilted. Suture slightly but sharply impressed. \Vhorls ~ or 3, closely appressed, rapidly expand­mg. Body whorl proportionately large, plump, almost semicircular in profile. Body whorl ornamented with about 17 clos~ly spaced, finely punctate spiral grooYes which are subequally spaced. Aperture crescentic~ sharply acute poster· iorly, less so anteriorly; anal canal pro­longed upward on the penultimate whorl; siphonal canal narrow, inclined upward toward its outer terminus. Outer lip Invertebrate Fossils of the Navarro Group thickened, with coarse longitudinal stria­tions, its upper end prolonged upward onto the penultimate whorl; inner margin of outer lip finely crenulated, except at the lower broadly curved margin which is smooth. Inner lip strongly callused at the outer margin, broadly excavated below. Bordering the upper side of the ascending anterior canal is a narrow, prominent fold which is so oblique as to incline down­ward as it passes into the shell; on the parietal wall somewhat back from the outer margin of the inner lip are at least 4 short very oblique fold-like processes which are distinct from each other and are irregularly distributed. Dimensions of the figured specimen: Height 2 mm., diameter, including the outer Iip, 2 mm. The description given is based on one small specimen which seems essentially like Wade's species americana, except that it is only about half as large. Should a large suite of specimens show this dif­ference in size to be constant, the Texas shell should perhaps be classed as a separate species, since it occurs in a higher stratigraphic position. This shell was ac­cidentally broken beyond repair after it was photographed. Types.-Holotype, U.S.N.M. no. 32836; from Coon Creek, McNairy County, Ten­nessee; 1 plesiotype? from Texas, U.S.N.M. no. 77206. Distribution in Texas.-Navarro group, Kemp clay: At a depth of 800 feet in a well 2 miles west of Groesbeck (13124) . Outside distribution.-Tennessee: Coon Creek tongue of Ripley formation. Family SCAPHANDRIDAE Genus ELLIPSOSCAPHA Stephenson, n.gen. Type species.-Cylichna striatella Shumard. Etymology.-Comhination of ellipsis (an ellipse) and scapha (a boat). Should a question be raised in the future as to the correctness of the identification of the shells here under consideration with Shumard's species, the present author ex­pressly specifies that the generic name Ellipsoscapha is based upon the species represented by the specimens here referred to Shumard's species, and described and illustrated in this work. The genotype of Scaphander Montfort is S. lignarius (Linne) , from the Recent seas of Europe; it is a large, convolute, umbilicate shell so openly coiled that one can see practically all of the interior to the apex which, however, is imperforate. The California Eocene shell, Scaphander ( Mirascapha) costatus (Gabb) Stewart, which Stewart455 made the type species of the subgenus M irascapha, is more slender and more closely coiled than the typical Scaphander. The Cretaceous shells to which the name Ellipsoscapha is here given, are similar to Mirascapha, but they approach more nearly an ellipse in vertical profile, are more tightly coiled, producing a nearly straight columella bearing a broad gentle fold, and have a much smaller, apical de­pression. Stewart assigned Scaphander ligniticus Aldrich, from the Eocene of Alabama, to Mirascapha. This shell is sufficiently coiled to form a sinuous columella; it is rather slender in its upper portion, widening to its maximum diameter a little below the midheight; it has a propor­tionately large open apical depression, with a wash of callus covering the bottom and extending part way up the sides. If this shell is correctly referred to Mira­scapha, its characters would seem to justify raising Mirascapha to the rank of genus. Another related shell is A bderos pira from the Chipola Miocene of Florida, which Dall456 described as a subgenus of Bullina, but which Stewart457 raised to the rank of genus. The type species, Bullina ( Abderospira) chipolana Dall, is a small shell having a profile similar to that of Ellipsoscapha, but more broadly ovate, a proportionately larger apical depression which appears to be perforate, a fairly open umbilical fissure and similar spiral sculpture. The species Haminea cylindrica Gard­ner,458 Bulla mortoni Forbes,419 Bulla 4MStcwart, Ralph B., Acad. Nat. Sci. Philadelphia Proc., vol. 78, p. 437, pl. 27, fig. 5, 19~6. 456Dall, Wm. H., U. S. Nat. Mus. Proc., vol. 18, p. 32, 1895. See also Wagner Free Inst. Sci. Trans., vol. 3, pt. 6, pl. 59, fig. 23, 1903. '67Stewart, Ralph B., Acad. Nat. Sci. Philadelphia Proc., vol. 78, p. 439, 1926. 468Gardner, Julia, Maryland Gcol. Survey, Upper Cretace. ous (2 vols.), p. 409, pl. 18, figs. 8, 9, 1916. 458Forbes, Edward, Quart. Jour, Geol. Soc. London, vol. 1, p. 63, text fig. a, 1845. The University of Texas Publication No. 4101 concin na '\VhitfieId,-tno Ifam inea occiden­talis Meek and Hayden, H. subcylindrica Meek and Hayden, and H. minor Meek and Hayden,461 belong in the new genus Ellipsoscapha. Haminea Gray is based on the Recent species, H. hydatis (Linne), which is a broadly subovate, rather openly coiled shell, almost smooth to the naked eye, but covered with closely spaced, finely wavy, submicroscopic spiral lines; it appears to belong to a decidedly different group than that to which Ellipsoscapha belongs. ELLIPSOSCAPHA STRIATELLA (Shumard) Pl. 73, figs. 29, 30 1861. Cylichna striatella Shumard, Boston Soc. Nat. Hist. Proc., vol. 8, p. 194. Shumard described this species as fol­lows: Shell elongate-ovate, rounded at apex, nearly elliptical, length almost double the width; spire umbilicate; aperture narrow, arched, with sub­parallel sides above the middle and gradually enlarging below to near the base, where it i:3 again slightly narrowed; umbilicus closed by the callus of the columella; surface marked with fine lines of growth, and from fifty-six to sixty distinct, revolving striae much narrower than the raised intervening spaces. Length 0.90 inch; width 0.48 inch. Shumard's description may he supple­mented by the following notes: The shell is convolute, the apex being submerged in a moderate! y deep depression about 1 mm. in diameter. In vertical profile the shell is suhelli ptical, the sides being very broadly convex with a very slight flatten­ing centrally. The sculpture consists of numerous sharply incised, obscurely punctate grooves, which are in general much narrower than the intervening flat surfaces, but which show marked uneven­ness in spacing; the spacing is much closer near the apex and on the lower part of the base than elsewhere. The shell is so closely coiled that the columella is nearly straight; and there is a broad, hut very weak fold on the columella. Dimensions of the figured neotype: Height 25 mm., diameter 12 mm.; the ' 00Whitfield, R. P.. V. S. Geol. Survey :\Ion., vol. 18, p. 189, pl. 23, figs. 12, 13, 1892. ••.ll:\feek, F. B .. Rept. U. S. Geo!. Suney Terr., vol. 9, pp. 271-273, 18i6. largest specimen in the collection is 28 mm. high. Ham inea cylirulrica Gardner402 is a closely related species of Ellipsoscapha, but the holotypc is a crushed, imperfectly preserved shell that cannot be satisfactorily compared with E. striatella. Bulla mortoni Forbes463 and B. concinna Whitfield/<>-! from the Upper Cretaceous of New Jersey, probably belong to Ellipso­scapha; the former has a more inflated body than E. striatella, and the latter has its greatest inflation too low for that species. H aminea subc-ylindrica Meek and Hay· den465 is closely analogous to the Texas species, but is proportionately less slender. A close! y related unstudied species sim· ilar to Ellipsoscapha striatella, but less slender, occurs in the Owl Creek formation in Mississippi (U.S.N.M. no. 20453). Types.-Neotype, U.S.N.M. no. 77207; 2 unfigured examples. U.S.N.M. no. 21040. Shumard's type material is believed to be lost. It is recorded as having been found in the so-called Ripley group of Navarro County, Texas. The original description is fairly complete and agrees well with the specimens from Chatfield here referred to Shumard's species. Distribution in Texas.-Navarro group, N acatoch sand: Road 3/5 mile east of Kaufman (14098); road 2 miles southwest of Kaufman (7546) ; vicinity of Chatfield ( 762, neotype, and 2 examples) ; field south of Chatfield (7569); 3/4 mile east of Chatfield (7571) ; 3/5 to 4/5 mile northeast of Chatfield (14117) ; vicinity of Corsicana (763) ; 4 miles north of Corsicana (17366) . Unidentified specimens of ELLIPSOSCAPHA Two imperfect specimens found in the Corsicana marl, on the old Frieze place, 2 3/5 miles north by east of Malta, Bowie County (16159), are similar to Ellipsoscapha striatella (Shumard), but 4G!!Gardner, Julia, Maryland Geol. Survey, Upper Cretaceous (2 vols.), p. 409, pl. 18, fig'!, 8, 9, 1916. 463Forbes, Edward, Quart. Jour. Geol. Soc. London, vol. 1, p. 63, text fig. a, 1845, • tUWbitfield, R. P., U. S. Geol. Survey Mon., vol. 18, p. 189, pl. 23, figs. 12, 13, 1892. 465Meek, F. B., Rept. U. S. Geol. Survey Terr., vol. 9, p. 272, pl. 18, figs. 10 a, b, 1876. Invertebrate Fossils of the Navar.ro Group appear to be proportionately more in­flated. U.S.N.M. no. 77208. A crushed specimen from the same formation on the San Antonio road, 6 miles east of Castroville, in Bexar County (15502), may be the same species as the preceding. U.S.N.M. no. 77209. In the same formation in a westward­facing bluff on Guadalupe River, 1 3/10 miles north of McQueeney, Guadalupe County (7637, U.S.N.M. no. 77210; and 15524, U.S.N.M. no. 77211), 3 imperfect internal molds of a large convolute gastropod, possibly an Ellipsoscapha, were found. The sculpture is weakly im­pressed on the molds and consists of numerous spiral grooves of some­what uneven spacing. The apical depres­sion is quite small, and similar to that of Ellipsoscapha. The most striking feature of the shell is its rotund form. The height of the largest specimen is 37 +mm., and the diameter is estimated to be about 24 mm. Two poorly preserved specimens from the Kemp clay, from a branch % mile south of McLeod school, 6% miles south­west of Currie, Navarro County ( 14139), appear to differ from Ellipsoscapha striatella (Shumard) in having much more sharply punctate spiral grooves. U.S.N.M. no. 77212. Family AKERATIDAE Genus AK.ERA Milller Type species.-Akera bullata Miiller,466 from the Recent seas of Europe. The one internal mold from Texas rep· resenting the genus Akera is remark­ably similar to A. bullata Miiller, but it differs in that the upper part of the shell is noticeably more constricted, the apex is somewhat more sunken, and the shell is proportionate! y a little less slender. A striking similarity exists in the size and position of the protoconchs of the two species. In the Recent species there is no columella other than the sinuous inner edge of the conch, and the Creta­ceous shell appears to correspond to the Recent one in this feature. There can be -i.llller. 0. F., Prodromu1 Zooloeiae Danicae. p. 242, 1776. scarceIy any doubt of the generic identity of the Cretaceous and Recent species. Although the Texas specimen has been referred to Bullo psis cretacea Conrad, as indicated by the accompanying label, Conrad's species belongs to an entirely different group having a columella with 2 strong folds, and differing markedly in other features. AKERA CONSTRICTA Stephenson, n.sp. Pl. 74, figs. 1-3 Shell small, thin. Spire exposed, but depressed, the rim of each successively smaller whorl being slightly lower than the preceding. Protoconch visible as a small, smooth bulb nestled in the center of the spiral depression. Whorls sepa· rated from each other in the spiral de­pression by a deep V-shaped groove, the inner wall of which is broadly convex, and the outer w·all broadly excavated; this groove is hounded on its outer side by a subacute, subangulated ridge which be­comes more round crested toward the aper­ture. The profile of the body whorl from the crest of the ridge above to the anterior extremity is broadly convex. The surface of the shell is nearly smooth, but it ex­hibits very small, narrow, very obscure, widely spaced spiral threads; under the most favorable light exceedingIy fine, closely spaced, very obscure spiral lines can harel y be detected under the micro­scope at several places on the surface. The fine growth lines bend strongly back­ward as they approach the crest of the sutural ridge above. The aperture is almost as long as the height of the shell; it is narrowIy acute at the posterior end, but widens out strongly below, and ends in a rather narrowly rounded anterior extremity. Outer Iip thin and broadly arched; inner lip broadly excavated and forming a thin wash of callus on the parietal wall. There is no columella other than the sinuous inner edge of the loosely coiled shell. Dimensions of the holotype: Height 9 mm., diameter 6.5 mm. The one specimen here described is the only known representative of this genus in the Cretaceous of the Atlantic and Gulf Coastal Plain. The Unil'ersity of Te.ms Publication No. 4101 llulotypc.----L~.">...~I. no. 21080. lhstrihution in Texas.-"'>\a\·arro group, \acatoch sand: Yicinity of Chatfield I -;-():2 I . Genus HAMINEA Gray HAMINEA? SIMPSONENSIS Stephenson, n.sp. Pl. 7~~ fig5. 9, 10 ~hell t)f medium size~ conYolute. loosely coiled. broadly subornte in Yertical pro­file. ~pire stmken and concealed; apical depression small. probably imperforate. The shell material is nearh· all gone from the polished internal mold~ but~the mold Lears the impressions of numerous ex­ternal. fine spiral grooYes which are minutely zigzag in trend; the grooYes on the lower half of the shell are finer and appear to be more obscure than those on the upper half. The aperture is as long as the total hei2:ht. is moderateIy wide open aboYe. wid~n~ out strongly ·below, but becomes rather sharply rounded at the anterior extremitY. The outer lio is • l. broadly co1H"ex abon.", becoming sharply curYed toward the anterior extremity. Inner lip deeply excaYated below the mid­height: parietal wall thinly washed with callus. Dimensions of the holotype: Height 11 mm.~ diameter 8.5 mm. This shell is similar in form to the Hecent Haminea hxdatis ~Linne), the genotype of IIam inea Gray, but the spiral !.?:rooYes are noticeabl,. coarser than the ~~xceedingly delicate~ . finely wa,·y, snb­minoscopic spiral lines of Linne~s species. Hal otype.-C.S.">.. .~I. no. 77213. Distribution in Texas.-"'>\a,·arro group, \al'atoch sand: Field 2 miles southwest of kaufman l. 75-l7~ holotype _1 ; '?-l miles north uf Corsicana l 17366). Genus CYLICHNA Loven4u. Type ~pecit·5. a~ subsequently designated by 1lerrmannsen.-l-6' -Bulla cylindracea Pen­ nant. The Qenus CYlichna differs from Ellipsosc~pha in .its much smaller size, 4 ·~~Ll•\ ;-n. 5.. lndt:>x mullu~.:LHUru LL--a :3canJina\·aiae l•c·ci,!c:i:.:iii.J h.iL:ur::ium. ;:i. 10, 1816. ~Ofras. K. Yetens .\c.:iJ. F~:rh. 5-tuclr.:h c:•lm. ml. 3 ~5), p. 1 -t~. :\foll.) 4 '3'HdrmJnn~.·n. :\. :\., lnJ..x Generum ~lalacozoorum, Su1·1 ·l,·m~·nt .i:d Cu~r i e; ,-nJ.J, p. -1~. 1852. its more slender and more nearly cylindri­cal form. its proportionately larger and more open spiral depression, its narrower aperture. and its weakt=>r and finer spiral sculpture. Each of these genera has a broad. weak fold on the columella, and they seem to be closely related. CYLICHNA SECALINA Shumard Pl. i +, figs. 4--6 1861. c,-/ichna secalina Shumard. Boston Soc. ·l\'at. Hist. Proc., rnl. 8. p. 195. The following is Shumard"s descrip· tion: Shell small. subcYlindrical. rounded at in· ferior extremity~ s.ubtruncate above. length more than double the width; 5pire umbilicate, aperture narrow. widest below. slightly ex· panded aboYe. and prolonged a little abow the summit of the b1.)dY of the sht"'ll: umbilicus cl1)5ed: surface with. very fine striae. of growth, and fine revohing striae. which are more dis· tinct near the extremities than the middle of the shell. spaces between irregular~ but broader than the 5triae. This shell maY be reaned on the wntt>r. The same is true of the Yenter of Eutrephoceras perlatus C\Iorton). Types.-Holotype~ r.S."\.:'.\I. no. 77223; 1 figured paratype~ l"5."\.:'.\I. no. 7722-1-: 1 figured paratype~ CS."\.:'.\I. no. 77225. _Distrib~1tion in Te.ras.-\"ayarro group. \eylandnlle marl: 21 ;2 miles north of Corbet I 1(,1 70. 17365 I : 2~ ~ miles south of Ben Hur (155-l3). "\arnrro group. "\acatoch sand: YieinitY of Kaufman t 76L 1 figured paratype l .: road 3 .5 mile west of Kaufman I 1-1098 l : Yicinity of Chatfield (7(>2. 1 fi~ured para­type I : ~..i mile east of Chatfield t 7571 l : 3 5 to -t--~ mile northeast of Chatfit>ld 11-1-117. loc. of holotype'l: 7 miles north of Chatfield t 17236 l : 21 ~ mile~ north of Corsicana 1)-1-ll-t."l ; north edge of Cor­s1cana (518); YicinitY of Corsicana "\~n-arro group. Corsicana marl: ?4 miles ~outlnrt"'~t of Quinlan (_17385). Outside distribution. - -Tennessee: Coon Creek ton~uf' of Hi pley formation. :Mississippi: ?HiplC'y formation. Unidentified specimens of EUTREPHOCERAS Small. incomplete. or crushed speci· mens of Eutrephoceras from the Corsicana mar1. too poorly preserved for specific identification. some of which may repre· sent l\Iorton·s4 ii p ro Yi s i o n a I species, Eutrephoceras perlatus (Morton), from the Prairie Bluff chalk of Alabama, are re· corded from the following localities: Public road l11.! miles south by east of Oak GroYe, Bowie County (16160, CS.\'.:\I. no. 77226) : from a small " 7 branch~ • H. Moore Suryey~ 100 yards ~outh of l\Iissouri, Kansas & Texas Rail­road. ~..1 mile east of west line of Survey, .S miles east by north of Greem·ille, Hunt County (12924, U.S.N.M. no. 77227) ~ 3 7 10 miles southwest of Campbell (1738-J.. U.S.\'.l\I. no. 77228) ; road ditch 1 t.~ miles N. 20° "r· of Tona siding, in Hunt County (15545, U.S.N.M. no. 77229) : Dallas road on west edO'e of . 0 Kaufman (7548, l1.S.~.~t no. 77230): dug well 7 /20 mile south by west of St. .\fary"s l"nin~rsity, Bexar County (16353, LS."\.:'.\I. no. 77231) ; cut on San An· tonio road~ 6 miles east of Castro\'ille, in Bexar County (15502, U.S.N.M. no. 77232). Order A\I:'.\lONOIDE:\ ~ubonler EXTR:\SIPHON:\TA Family PTYCHOCERATIDAE Genus SOLENOCERAS Conradt7s Type s1wcies.-Hamites annuli/er ~lorton ;4i9 from the ferrug:inous sand [Crosswicks clay] t:'o in the deep cut of the Chesa· peake and Delaware C:rnal, Delaware. °' 77'.\1orton, S. G.. Synop,;;is of the organic rC'mains of the Crl'laccou~ group of the Cnitcc. Proc., vol. 32, p. 580. Shumard described this species as fol­lows: Shell small and fngile, gently convex on the sides, and flattened on the dorsum [venter] ; larger, or body portion, very slightly tapering to the curve behind, and marked with a mod­erately deep gutter on the ventral [dorsal] side. for the reception of the convex inner side of the slender portion, the transverse section of which is broad ovate; surface marked with strong, simple, annular costae, which are slightly oblique, wider than the spaces between, and on the dorsum [venter] each bearing two slightly elongated nodes. This shell differs from Ptychoceras (Hamites) annuli/er of Morton and P. mortoni Meek and Hayden, by its flattened form and larger size. also from the former by its nodose ribs, and from the latter by its simple instead of divided costae. Formation and locality. Cretaceous septariae (Ripley group), near Chatfield Point and Cor­sicana, Navarro County. Shumard's type material is lost, but a neotype is selected from a lot of three individuals ( topotypes) from Chatfield (762), in the collection of the United States National Museum. These were col­lected and identified by Dr. T. W. Stanton in 1890, and were later ( 1894.) studied by '88Meck, F. B., Rcpt. U. S. Geol. Survey Terr., vol. 9, pp. 410-412, 1876. The University of Te.ras Publication No. 4101 Dr. Alpheus Hyatt. Shumanrs (h•scrip­tion ap1wars to be good. though it docs not indicate the rnriation in st rcng:h, width, and spacing of the ribs. the varia­tion in the size and spacing of the nodes. and the usual absence of both ribs and nodes on the earlier parts of the conch, which the species of this genus exhibit. On the neotype (pl. 79, figs. 1. 2) the living chamber is compressed laterally and extends backward nearly around the main flexure which charactei·izes the shells of this genus. On the living chamber the ribs are strong and, on the sides~ are markedly oblique backward from the dorsum. Back of the living chamber on the smaller limb of the shell the ribs are oblique forward from the dorsum instead of backward, and are of unequal development on different individuals; more commonly they are weak and irregular, but on an occasional individual they are strong and regular. The nodes on the venter are slightly elongated in the linear direction of the shell, and vary greatly in strength on the different ribs and on different parts of the shell; on the neotype they are strong on the most advanced part of the incompletel v preserved living chamber, become weak backward, strengthen up again around the main bend, and become weak again back of the living chamber. On another speci­men two marked annular constrictions ap­pear about 8 mm. apart on the small, nearly smooth, early portion of the conch. and it appears that such constrictions may he present at almost any position on the shell, though always widely separatt>d. The adult suture as shown on the neotype con­sists of 6 rather simple loht>s and saddlt>s of onl~· moderate dt>pth. Tht> siphonal lobe is bifid and slightly acentrie, and the two digitations are faintly bifid. rather widely separated, and dirPctt>d obliquely toward the side. Tlw first lateral saddle i~ hifid. rather hroad. and the two sub­saddles an' Pach faintly bifid. The first lateral lohe is similar to the siphonal lobe, but is not quite so broad and tlw sublolws are less oblique. The second lateral saddle resembles the first hut is noticeably broader. The second lateral lobe is much like the first in size and digitation. The dorsal saddles are proportionately very small and each is faintly bifid. The anti­ siphonal lobe is small, shallow and almost simple. A fin<' specimen from the Neylandville marl (pl. 77, figs. ·1., 5), which is regarded as belonging to thi~ species, is long and gently tapering. and has the costae strongly and nt"arly regularly developed on the hody chamber, which also exhibits a prom. inent. regular development of the double row of nodes on the venter; the rest of the shell is nearly smooth with the exception of 4 or 5 well-marked, widely spaced constrictions; the living chamber is more strongly compressed posteriorly than it is toward the aperture, and the remaining slender portion of the shell is broadly subovate in cross section. One fragment in this lot exhibits sutures similar to that of the neotype except that the sutures are slightly more intricate in pattern. The neotype has a maximum dorso· ventral diameter of 1.8 mm., and a lateral diameter of 3.8 mm. In its doubled form the specimen from the Neylandville marl shown in plate 77, figures 4, 5, measures 36 mm. in length; if straightened out the conch would measure 71 +mm.; neither the large nor the small end of the conch is quite complete; the maximum dorso· ventral diameter is 5 mm., and the lateral diameter 5 mm.; farther back the sides become compressed, the corresponding dimensions being 4.5 and 4, mm. The type of Solenoceras annuli/er (Morton), an internal mold of the body chamber only. is obviously specifically distinct from .S. texanum. It is a plump species, lacking the characteristic lateral compression of the latter species, and, according to Whitfield,4~-t has only a weak development of nodes on the venter. .Solenoceras mortoni (Meek and Hay· den) , 485 from the Pierre shale at the Great Bend of Missouri River, in the Western Interior, is a closely related species. Sole· noceras eras.mm (Whitfield) and S. meek· anzun (Whitfield), also from the Pierre shale, are closely related species, but they are larger and more coarsely sculptured at all stages than the Texas species. Types.-Shumard's type material, from Hear Chatfield, Navarro County, is lost. 4$ 1Whitfi<'1d. R. P., U. S. Gcol. Survey Mon., vol. 18, pp. 273·274, 1892. 485".\fcck, F. B., Re-pt. U. S. Geo!. Survey Terr., vol. 9, p. 412, pl. 20, figs. 4a-b, 1876. Invertebrate Fossils of the Navarro Group The specimen shown in plate 79, figures 1, 2, from Chatfield (U.S.N.M. no. 21092a), is chosen as neotype; 1 other incomplete topotype from the same locality is figured, U.S.N..M. no. 21092b; several unfigured topotypes from the same locality, U.S.N.M. no. 21092; 1 typical specimen (pl. 77, figs. 4, 5) figured, U.S.N.M. no. 77237. Dutribution in Texas.-Navarro group, Neylandville marl: 2¥2 miles north of Corbet (16170; 17365; Tex. Bu. 17300); 2% miles south of Ben Hur ( 15543, 1 specimen figured) . Navarro group, Nacatoch sand: Vicinity of Chatfield ( 762, loc. of neotype) ; 3 miles northeast of Corsicana ( 9545) ; 4 miles north of Corsicana ( 17366) ; 2 miles north of Corsicana ( 9555) ; ?3 3 /10 miles west-southwest of Corsicana ( 16163) ; 2112 miles west by south of Corsicana ( 17368) . Range.-Neylandville marl and Naca­toch sand of the Navarro group. SOLENOCERAS REESIDEI Stephenson, n.ap. Pl. 77, figs. 1-3 Shell small, long and slender, and bent back upon itself in the manner charac­teristic of the genus. The two limbs of the shell are closely in contact, the smaller limb resting in a groove in the larger limb. The bend is sharp, leaving the umbilical perforation very small or wanting. Sides of living chamber broadly to plumply rounded; venter evenly rounded, or only slightly flattened. The cross section of the smaller limb is near 1y circular at the small end, becoming broadly ovate in outline transverse to the plane of coiling, with no flattening on the venter. The venter be­comes noticeably flattened around the bend connecting the two limbs. The living chamber is ornamented with strong rather sharp ribs, narrower than the interspaces which, on the holotype, number about 14 to the centimeter; on this limb the ribs slope a little backward from the dorsum. The two ribs nearest the aperture are much stronger than the others and are separated by a deep, relatively broad constriction; a similar feature is exhibited by at least 5 of the available shells and is obviously a mark of senility. The incomplete small limb of the holotype is covered with small, sharp ribs to within 5 mm. of the extrem­ity, where the surface becomes nearly smooth; these ribs number 23 or more to the centimeter; they slope a little forward from the dorsum; the available material shows that the small limb may be smooth for differing distances from the apex on different individuals, up to 15 mm. or more. Widely spaced annular constric­tions are present on the small limb of most individuals. A double row of small nodes is present on the venter around the bend connecting the two limbs and is traceable as far as the orifice on the living chamber of most specimens; on the small limb the nodes are traceable backward from the bend for differing distances on different shells, but they fade out before the apex is reached. The shell is thin at the aperture and there is no recognizable hyponomic sinus. The sutures are not exposed on the type material, but on specimens from the Nacatoch sand near Corsicana (761) the sutures are very much like those of S. texanum (Shumard) ; they are shallow and rather simple, the lateral saddles being broader than the intervening lobes. The length of the holotype, measured as accurately as possible around the bend, is 53 mm.; an undetermined apical portion of the shell is broken away. The length of the large limb is 22.5 mm. and of the small limb 30.5 mm., the latter projecting 7 or 8 mm. beyond the aperture of the former. The diameter of the smallest part of the shell preserved is 2 mm.; the dorso­ventral diameter of the aperture is 4.7 mm., and the transverse diameter 4.2 mm. The ribbing on the type of Solenoceras annuli/er (Morton) is similar to that on S. reesidei, but the latter is more com­pressed and has a proportionately longer dorso-ventral diameter; Morton's species is from an older formation ( Crosswicks clay, New Jersey; Exogyra ponderosa zone). Compared with S. texanum this species has more numerous ribs, the small limb is typically more completely covered with ribs, the ventral nodes are smaller and less prominently developed, and the two limbs are more closely compressed together. None of the described species from the Cretaceous of the Western Interior are apt to be confused with S. reesidei. Types.-Holotype, U.S.N.M. no. 77238; 4 unfigured paratypes, U.S.N.M. no. 77239. The Uniz·ersity of Te.ras Publication No. 4101 "\amPs art> wt>ak and irregular on the small limb but the two rows are traceable for 10 mm. or more backward from the bend. The thin margin of the aperture is partly preserYed. L The length of the incomplete holotype if straird1tened out would be +l mm. The diamet~r of the small broken end is 2 mm. The dorso-wntral diameter of the aperture measures -1-.2 mm. and the trans­Yerse diameter -l.5 mm. The greatest trans\·erse diameter of the liYing chamber just in front of the bend is 5.5 mm. One specimen from near Corsicana I 5181 resembles the holotype except that tlw ribs on the liYing chamber for about 7 mm. back from the aperture are a little coar~er and more widely spaced than on otlwr part!" of the shell. Compared with tlw type of Solenoreras ?nnu!ifer (Mor· ton 'I l == llamites annuli.fer l\forton), S. multicostatum is closeh· related. but its rihs are finn and more closely .crowded ( l-9 YC'rsus 1-l to 1 centimeter).. it is more compressed in the lateral dimension, and is less compressed in the dorso-Yentral dimension. Holotype.-r.S.\'.M. no. 21050. Distribution in Texa.s.-N'aYarro group, :\"acatoch sand: Vicinity of Chatfield (762, type loc.) ; north edge of Corsicana (518); 21 ~ miles west by south of Corsicana (17368). Family HA~UTIDAE Genus HAMITES Parkinson HAMITES? sp. Sewral fragments from the Corsicana marl in a westward-facing bluff on Guada­lupe RiYer. 1 3 ·10 miles north of Mc­Queeney. Guadalupe County (15524), are curYed portions of }i,·ing chambers orna· mented with ribs like those of Hamz~tes. :\"odes are wanting. The specimens are too incomplete for satisfactory identification. CS."\.~I. no. 772-10. Family BACCLITIDAE Genus BACULITES Lamarck The shells of Baculites Lamarck are newr found in a complete state of pres· sen·ation. the reasons being their great length in proportion to their diameter, the fragile nature of the shell material, and the accidents to which they are subject during the processes of burial and fossilization. Because of the fragmentary condition of the material. the species of Baculites are difficult to determine. It is also generally difficult to determine whether or not de· tached fragments of small indidduals are the young stages of the species represented by larger fragments in the same collection, or from elsewhere in the same f onnation. The difficulty of identification is increased bY the Yariation in form and in suture pattern of the indiYiduals within a given species. The remains of Baculites found in the ~aYarro group of Texas present the usual difficulties in identification. Some Invertebrate Fossils of the Navarro Group of the fragments are, however, well pre­served both as to form and the pattern of the suture. As interpreted most of the material belongs to two species, Baculites clavi/ormis and B. undatus. At least four other species are, however, represented by meager material. BACULITES CLAVIFORMIS Stephenson, n.sp. Pl. I ; pl. 77, figs. 6-8; pl. 78, figs. 1-6 Shell of adult large, attaining an esti­mated maximum length of over 170 centi­meters (5.5 + feet). In general the shell tapers rapidly for the genus, but the indi­viduals vary considerably in the degree of tapering. The ovate cross section is modified by a broad flattening of the dorsal surf ace, and noticeable flattening on the sides toward the venter, thus producing a more sharply rounded ventral edge; the dorsal flattening is scarcely noticeable in young stages, but becomes a marked fea­ture as the shell approaches half an inch in diameter, and in the older stages is one of the principal characters separating this species from B. ovatus Say. The shell is smooth in the young stages but at differing distances from the apex on different in­dividuals begins to develop broad, gentle undulations on the sides, and numerous more or less pronounced growtl;t corruga­tions on the venter and on the adjacent slopes. The undulations are a little more than half as long as the dorso-ventral axis, are broadly curved concave toward the aperture, and lie nearest the dorsal side. On typical specimens the undulations do not become prominent until the shell has reached I1;2 or 2 inches in its dorso­ventral diameter. The growth corruga­tions on the venter are closely spaced, ex­tend obliquely backward on the sides parallel to the margin of the aperture, and each corrugation fades out near or a little before reaching the center line of the side; similar, though much fainter, growth cor­rugations ornament the flattened dorsal area of some shells. These corrugations are not equally developed on all individ­uals and may be practically wanting on some. The sutures consist of six finely but not deeply digitate saddles and six similarly digitate lobes. The siphonal lobe is very broad and only moderately deep, and is subdivided by a broad ventral saddle into two tripartite sublobes. The ventral saddle is about two-thirds as high as the ventral lobe is deep, is tripartite, finely digitate, and the two outer subsaddles are higher and much broader than the median sub­saddle; the latter may be single, bipartite or irregularly digitate and in the young stages appears to be consistent!y very small and narrow. The lateral saddles are broad, subequal, bipartite, and finely digi­tate; the sub lobe is narrow and about one­third as deep as the height of the saddle. The first lateral lobe is moderately digi­tate, is much narrower than the saddles and is bipartite; the subsaddle is small and narrow and is about three-tenths as high as the depth of the lobe. The second lateral lobe is broader than the first, is bipartite, and though nearly symmetrical is slightly oblique; the subsaddle is short, proportionately broad, nearly smooth in the young stages, becoming finely digitate in the later stages of large shells. The dorsal saddle is proportionately very broad, but is much shorter than the lateral saddles; it is bifid, the sub lobe being small, narrow, and about one-fourth as deep as the saddle is high. The antisi­phonal lobe is small, narrow, rather finely digitate, and more than half as deep as the adjoining dorsal saddles are high. The incomplete holotype measures: Length 198 +mm.; maximum dorso­ventral diameter 66 mm., maximum trans­verse diameter 4 7 .5 mm. ; at small end dorsal-ventral diameter 49 mm., transverse diameter 32 mm. The large exhibition specimen, described below, measures at large end: Dorso-ventral diameter 180 mm.; transverse diameter 115 mm. The next largest specimen, also from near Kaufman (14099), measures: Dorso-ven­tral diameter 87 mm.; transverse diameter 65 mm. The largest specimens from the Neyland­ville marl, which are referred questionably to B. claviformis, are smaller than the largest specimens from the N acatoch sand, but they do reach a maximum measured dorso-ventral diameter of 65 mm. These larger shells are more slender than those from the Nacatoch, but, as already stated, this feature is of doubtful importance as a specific character. Such minor differences as may be observed in shells from the two The Unirersity of Tc:ras Publication No. 4101 formations are probably within the range of individual variation. The largest known shdl of B. clavi­fonnis, and incidentalh one of the larrre~t shells of the genus ~ver collected i~1y­where. is one from the Nacato\h sand. now on exhibition in the National Mus~um (no. 20953) ; it is labelled B. grand£s Hall and Meek (see frontispiece). This speci­men was collected by Dr. T. '\V. Stanton in 1890 from a large mass of \akareous, concretionary sandstone, in a road cut about 2 miles south-southwest of Kauf­man. The specimen as found was not a complete indiYidual, but was the large end of the shell, including an unde­termined portion of the living chamber: sutures can be seen to within 45 or 50 centimeters of the large end; the specimen on exhibition is in part a restoration made by Dr. Charles Schuchert, at that time a member of the museum staff; parts of other individuals were introduced to com­plete the smaller end and some interven­ing spaces were filled in with plaster of paris. The authentic part of the specimen, measured along the dorsum, is about 88 centimeters long and the large end is incomplete; the dorsum is flattened as in the typical B. clavi/ormis; the dorso­ventral diameter at the large end is about ]80 mm., and the tramwer~e diameter 115 mm. (estimated) ; at the small end the dorso-ventral diameter is about 66 mm. The characteristic broad lateral undula­tions are present and continue with dimin­ishing prominence to the large extremity; these do not show well in the illustration. The authentic part of this indiYidual is followed apically by a section about 20 c<:>ntimet<:>rs long. which bears the cata­logue number 20965, and presumably be­lonfrs to another indiYidual. although .from its state of preservation it might well be­long to the same indi,·idual. The small end of the restored shell has a dorso­Yentral diameter of 19 mm. The total length of the restored specimen, measured along the dorsum, is about 1.5 meters; if the restoration had been made complete to the protoconch 20 or more centimeters would ha,·e had to be added to the lenoth as gfren. In its older stages the specin~en cleparts from the usual straight trend of the ~hell. and describes a broad curve concan"' on the dorsal side, as shown in plate l (frontispiece) ; the curved portion i~ ahoul HO centimeters long. The gentle nirn·s in the reconstructed small end of the specimen, as shown in the illustration cited. gin=.. an incorrect impression of this part of the shell. which should be ap· proximately straight. The three smallest pieces in the reconstructed end are in· correctly mounted, each of them having been turned 180 degrees in the longi· tudinal axis, so that the dorsum and venter occupy the reverse of their proper posi· lions. Specimens from the Neylandville marl at two localities (13835 and 16166), sho\v a compression on the sides similar to that exhibited by Baculites compressus Say, but not as pronounced. On the larger specimens, however, the dorsum is flat· tened as in B. claviformis, and they may represent a varietal form of that species. For the present they are questionably re· ferred to B. clavif ormis. B. claviformis differs from B. ovatus Say mainly in its great size and in the pronounced broad flattening of the dorsal area. Baculites grandis Hall and Meek,486 from "Mauvaises Terres, head of Bear Creek," South Dakota, from beds now known to belong to the uppermost part of the Pierre shale, is closely related to B. c!aviformis, but the types in the American Museum of Natural History (nos. 9545 I 16 ) and 95 indicate a shell having a pro· 1 portionately greater transverse diameter, more eY<:'nly and broadly rounded sides, and more broadly rounded venter. Types.-Holotype, U.S.N.M. no. 77241; 2 figured paratypes (young individuals), U.S.~.l\I. no. 77242; 2 unfigured para· types, U.S.N.M. no. 77243; 3 unfigured paratypes, U.S.N.M. no. 77244. Distribution in Texas.-Navarro group, Neylandville marl: 2 / 5 mile north of Cooper (14063) ; n /:! mile north of 4 :-11Hall, James, nnd or excentric young as in Emperoceras. In the anagerontic substage the whorl bends downwards or orally in two dextral specimens, and in the metageront ic acquires larger tubercles and coarser cos tac, sometimes bifurcated, and bend.., upwards towards the bast" of ephebic volu­t inn, forming the retrov<>rsal living chamber. The last part of this, or the paragerontic substage, is nearly or quite straight, the bifurcations dis­appear, leaving the costae straight, and the tuberdes also gradually disappear. The latest senile substage is also nearly if not quite bilaterally symmetrical and strongly contrasts in this respect with all the stages preceding the metagerontic substage. The return to the symmetrical form of whorl really begins in the metagerontic substage. The living chamber has an aperture in one specimen. This is straight acros..; the venter, has slight crests on the sides, and is straight or with very slight crest on the do rs um. The cotype shown in plate 80, figures 3-5, was regarded by Hyatt as two in­dividuals, as shown by the following pen­cilled note in his handwriting in the tray with the other cotypes. "Variety retroswn has two specimens anchylosed or jammed together, and one large specimen without retroversal chamber." In other words the two cotypes were considered by him to be three individuals. The so-called anchylosed specimen instead of being two individuals is in reality one nearly perfect shell which was mechanically fissured after fossilization, and the fissure was subsequently filled with crystalline calcite, forming a vein I to 7 mm. thick. The trace of this vein, which runs verticallv through the retroversal volution and up­ward through the spire, may be seen in plate 80, figures 3-5. In the retroversal volution, however, the fissure, although it split the shell approximately into halves, did not so divide the internal mold, but merely separated one of the halves of the shell from the mold, permitting the forma­tion of the calcite vein in the space be­tween the shell and the mold. The hcif!ht of the slightly inc om pletc deft cotyµe just described is 71 mm. The measurements ~iven by Hyatt pertain to l he other ('Ot) pe (pl. 80, fig. 2) , which la<"ks tlw rel roversal volution. The umbilical opt>ning of this specimen, which was rn\·en~d with matrix at the time Hyatt cxamine mile northeast of Chatfield (14117, 1 specimen figured); 2 1/10 miles northeast of Chatfield (Tex. Bu. 17302). NOSTOCERAS STANTON! ABERRANS Hyatt Pl. 80, figs. 9, 10 1894. N ostoceras stantoni aberrans Hyatt, Am. Philos. Soc. Proc., vol. 32, p. 572. The original description of this variety is as follows: This variety may have three, four or five dosely coiled whorls and considerable variation in the tuberculations, etc., but when the gerontic stage begins, the aspect is distinct. The anagerontic substage does not bend so abruptly as in retrosum or prematurum; it is more oblique to the axis of the spire and the retroversal meta­gerontic substage, if it be superadded in this variety, would be more oblique than in var. prematurum. One specimen is dextral and the other is sinistral. The meager material available for comparison justifies the recognition of this as a separate variety. The two co­types, though showing individual varia­tion in sculpture, agree in the aberrant form of the gerontic shell. The spires agree rather closeIy with N ostoceras stantoni prematurum, and the possibility should be recognized that these may be pathologic shells of that variety. Types.-1 figured cotype, U.S.N.M. no. 23280a; 1 unfigured cotype, U.S.N.M. no. 23280b. Distribution in Texas.-Navarro group, Nacatoch sand: Vicinity of Chatfield 410 The Unirersity of Te~ras Publication No. 4101 ,·76:2. tqw luc.) : 3 5 to -t. ~ mile north­ea~t of Chat field 1 1-i11 7·1 : 2 1 I 0 miles 1wrtheast uf Chatfield 1.Tex. Bu. 17~~02). NOSTOCERAS HYATTI Stephenson, n.sp. Pl. 81. fig~. 9-12 The earliest sta£es of the shell in this ~pffies haYe not been seen. The spire t ·un~ists of i or 5 Yolutions which rise and draw in rather rapidly toward the apex: the apical angle is about 60 degrees~ but the slopes bdow diYerge to an angle of about 80 degrees. On one of the co­t y pes the conta~t groow seems to. disap­pear at a position such as to indicate a minimum spiral diameter of about 6 mm., and an uncoiled shell in the earliest stage. The final Yolution of the shell, which cor­responds approximately to the liYing d1amber. is retroYersal and is essentially like that of typical .Yostoceras starztoni. The shell is large and the ornamentation is coarser than .__that on stantoni and its Yanet1es. On the spire the ribs are ir­regular in prominence and spacing and are in general rather sharp-crested though sume of the larger ones are round-crested. The ribs may be simple or may bifurcate, in places wry erratically. there being no recognizable s Ystem in this feature; gen­erall\ a node .is the point of bifurcation, hut this is not always so. On the large retron"rsal \ olutions ~f seYeral indiYiduals the ribs are t·onsistently strong and widely ~paced. The two rows of nodes are prom­inl"nth· deYeloped. The nodes Yary in streng.th but in general increase in size in the forward direction until theY become quite large around the main be1~d of the retroYersal whorl. beyond which they be­nrn1e marked!,. weaker. In cross section the shell is st;bcircular in the spiral por­tiun. becomes depressed to broadly ornte in the earh· and middle stages of the retro\ ersal . \·olution. and ~ubcircular again in the straight portion approaching the aperture. In the holotype tpl. 81, fig. 9 the diameter of the umbilical (.peninp-is about 15 nun. The sutures are not full~-unro\'ered on any of the a\ ailable material. but on one medium ~ized shell the siphonal lobe. the first lateral saddle. and the first lateral lobe appear to agree essentially with the cor­responding f ea t u r e s on Sostoceras ....tantoni. The hei mile northeast of Chatfield (7572~ 1-1117); north edge of Corsicana t518, type loc.) ; Yicinity of Corsicana l763) ; 21 ~ miles west by south of Corsicana ( 1 7368) . NOSTOCERAS HELICINUM (Shumard) PI. 80, figs. II, 12 1861. Turrilites helicinus Shumard, Boston Soc. I\at. Hist. Proc., ml. 8, p. 191. 189-t Xostoceras helicinum (Shumard). Hyat~ Am. Philos. Soc. Proc., YOI. 32, p. 573. On part.) The original description by Shumard is as follows: Shell sinistral. depressed conical. composed of about fiye rounded, contiguous rnlutions; spire Yery short ; spiral angle about 80° ; suture ,·e~ deeply impressed; aperture subcircular; umb1l· icus deep, exhibiting the inner rnlutions, not as wide as the last rnlution: surface ornamented with prominent, sharp, annular costae, which, on the last rnlution, pass obliquely backwards from the umbilicus to the suture. The costae are usually simple, but occasionally they bifurcate, and this generally occur:; near the edge of the umbilicus; about forty ribs may be counted on Invertebrate Fossils of the Navarro Group the last volution. The ribs of the last volution, in some specimens, are garnished with a double series of small indistinct nodes, situated on the middle third of the volution. No traces of nodes have been observed on the turns of the spire. This shell resembles in many respects Turrilites utkrianus, D'Orbigny (Palaeont. Franc. T. 1, p. 578, pl. 140, figs. 8-11), from which it may be at once distinguished by the nodes upon the last volution, when they are present. In specimens without nodes, there are no well marked char­acters to separate our shell from the foreign species. It cannot be confounded with any of the known Turrilites from American strata. With the preceding species [Turrilites splen­tlidU$] at Chatfield Point and Corsicana, Navarro County. Two specimens, identified by Dr. T. W. Stanton, furnished the basis for the fol­lowing description of the species by Hyatt: At the diameter of 8 mm. in one of the two specimens before me, there are indications that the young was more loosely coiled, and perhaps more or less excentric in comparison with the later closer-coiled stages. The contact furrow was also obviously absent in these earlier sub­stages. In the other specimen, at diameter of about 9 mm., there are similar indications. Nevenheless, I was by no means sure of what these changes indicated, whether a helicoceran, scaphetoid or hamites-like shell. All that can be said is that they show irregularities in the growth of the young not present in the turril­lireaq volutions of the ephebic stage. The young, probably in the anephebic sub­stage, has single costae, each tuberculated on either side of the venter. These become more or less irregularly bifurcated, and with inter­mediate entire costae without tubercles, usually one, sometimes two, in each interspace in the metephebic substage. The whole is a flat turbinated coil of not more than four or five whorls with prominent tubercles and costations. In the anagerontic substage the volution abandons the spiral, the contact furrow disap­pearing immediately, and the shell grows down­wards and outwards, as in the anagerontic sub­stage of Nostoceras Stantoni, var. aberrans. The single tuberculated costae of the young are similar to those of the later stages of Ancyloceras /ennyi, Whitf., Pal.. Black Hills, and some of the helicoceran forms found else­where; but the young shells were obviously quite dift'erent, being more closely coiled and stouter shells. Specimen in Coll. U.S. Nat. Mus., No. 21103. In the absence of Shumard's types, which are lost, it may never be positively known that the two shells selected by Doctor Stanton, and described by Hyatt, correctly represent the species. The specimen shown in plate 80, figures 11, 12, is selected as neotype. The other specimen is so mark­edly different in ornamentation that it is here classed as a varietal form, N. heli­cinum crassum. It was this varietal speci­men that furnished the basis for Hyatt's description of the gerontic portion of the shell. None of the specimens here referred to the typical helicinum have more than the very beginning of this gerontic por­tion preserved. Shumard's statement that the bifurcations of the costae generally take place near the edge of the umbilicus needs modification, for on the neotype and other specimens some of the costae bif ur­cate at the nodes. None of the specimens in our present collections are en ti rely without nodes on the volutions of the spire, as stated by Shumard, but on some the nodes are very weak; evident! y this is a variable feature, but the nodes on the spire are in general small and do not become prominent until the gerontic stage is ap­proached. On the spire the lower row of nodes may be at the line of contact between the volution and the next one below, or it may be either a little above or a little below this contact. There is considerable difference in the prominence and spacing of the costae on different parts of a given individual, but in general the costae are numerous and closely spaced; the costae become markedly wider apart on the earliest portion of the gerontic stage. The costae bearing nodes may be separated by one, two, or three costae without nodes. The sutures are not well exposed on the specimen studied. The height of the incomplete spire of the neotype is 31 +mm.; the dorso-ventral diameter at the beginning of the gerontic stage is about 15 mm., and the transverse diameter 16.5 mm.; the narrow, ovate umbilical opening is about 10 mm. long and 5 mm. wide. Types.-Shumard's type material is lost; he records the species as from Chatfield and Corsicana, Navarro County, Texas. Neotype: U.S.N.M. no. 21103a. Distribution in Texas.-Navarro group, Nacatoch sand: Vicinity of Kaufman (761) ; vicinity of Chatfield ( 762, type loc.) ; 3 /5 to 4 /5 mile northeast of Chat­field (14117) ; llz mile east of Chatfield (7570); 21h miles north of Corsicana (14114); north edge of Corsicana (518); vicinity of Corsicana ( 763). The Uni-versify of Texas Publication No. 4101 NOSTOCERAS HELICINUM CRASSUM Stephenson, n.var. Pl. 81, figs. 7, 8 One of the l wo shells identified by Dr. T. W. Stanton, as Shumard's Turrilites helicinus, and later described by Alpheus Hyatt as Nostoceras helicinzun lShumard), is much more coarsely ornamented than the other and has a lower spire; it also has a mo;·c open spire at the apex, indicat­ing a longer uncoiled initial stage. At the earliest coiled stage, the costae are equally as fine as on the typical helicinum but the intercostal spaces gradually widen ?ut causing a much coarser ornamentat10n throuahout the remainder of the length of th; conch the maximum separation of the costae i~ the gerontic stage being 5 mm. Except on the smallest volution of the spire the nodes are prominent and are about equally strong in each row; the costae bearirirr nodes are generally sep­arated by either one or two costae which are either nodeless or bear only small, obscure nodal swellings; the nodes become markedIy prominent and coarse in t~e gerontic stage. The shell in the ger~ntic stage becomes uncoiled, expands rapidly, and extends horizontally away with a sliaht twist and a very gentle curve down­wa~d. Nothincr is definitely known of the lenath or forntof. the uncoiled initial stage of fhe shell, but the contact groove i~di­cates that the diameter of the first volut10n is about 10 mm. The holotype as a whole has a maximum length of 57 mm.; the max~mum dorso­ventral diameter of the geront1c part of the shell is 17.5 mm., and the maximum trans­verse diameter 20. 7 mm.; the correspond­ing dimensions at the beginning of the rrerontic staae are 13.5 and 16.8 mm.; the heirrht of the incomplete spire is 23 + nm~; the ovate umbilical opening has a maximum diameter of about 11 mm., and a minimum diameter of 7 mm. A poorly preserved, coarsely sculptured µaratype which accompanies the holotype has the gerontic stage represented by a long, smooth, irregular internal mo~d which has the appearance of a pathologic condition; the shell becomes free from the ~pire at about the same size as in the holo­type, hut it expands and contracts irregu­larly and bends down strongly toward the aperture; it has a maximum diameter of fully 22 mm. Types.-Holotype, U.S.N.M. no. 77261; l unfigurcd paratype, U.S.N.M. no. 77262. Distribution in Texas.-Navarro group, Nacatoch sand: Vicinity of Ch()tfield (762, type loc.) ; field south of Chatfield (7569); 2~ miles north of Corsicana (14114); vicinity of Corsicana (763); north edge of Corsicana (518). NOSTOCERAS HELICINUM HUMILE Stephenson, n.var. Pl. 81, figs. 4-6 Two shells in the collections are similar to the variety crassum, but differ in the following features: The spire is lower and more open at the apex, the first volution of the spire is more slender, and the nodes of the two rows differ markedly in size, those of the upper row being prominent and strong, in contrast to small weak ones in the lower row. The holotype appears to be a young individual for the aperture is partly preserved, and the shell has not reached the uncoiled gerontic stage; the living chamber takes up about two-thirds of the largest volution. The other speci­men, though about the same size, is an incomplete older individual, for a septum is present at the large end. The gerontic stage is unknown. In features other than those mentioned this variety appears to be essentially like the variety crassum. The greatest diameter of the holotype is 29.3 mm., and the height of the spire is 15 mm.; the dorso-ventral diameter at the aperture is about 10 mm., and the trans­verse diameter about the same. The open­ing at the apex has a diameter of about. 8 mm., and the umbilical opening a dia­meter of 12 mm. The smallest diameter of the shell as preserved is about 1.5 mm. Types.-Holotype, U.S.N.M. no. 77263; 1 unfigured paratype, U .S.N .M. no. 77264. Distribution in Texas.-Navarro group, Nacatoch sand: Field 3/5 mile west of Kaufman (14103, holotype) ; vicinity of Kaufman (761, paratype). NOSTOCERAS COLUBRIFORMIS Stephenson, n.sp. Pl. 81, figs. 1-3 The spire is tall and consists of 5 or 6 volutions; the free portion of the conch forms a short, sharply turned retroversal volution. Two or 3 of the apical volutions Invertebrate Fossils of the Navarro Group of the holotype are broken away and the terminus of the retroversal volution is im­perfect. Spiral angle 40 degrees. The conch is broadly subovate in cross section and the diameters of the retroversal volu­tion near its terminus are respective! y 7.5 and 9 mm. The paratypes show that the initial volution may have a diameter of 3 mm. or less, and the smallest diameter of the conch is I mm. or less. The spire of the holotype is sinistral; 2 of the para­types are sinistral and 7 dextral. The total height of the incomplete holotype is 31.4 mm., and the greater diameter of the spire 16 mm. The surface of the shell, with the exception of the earliest volution, seen on one of the paratypes, is ornamented with approximately regular, narrow, subangu­lar ribs which number 12 or more to the centimeter. At widely spaced intervals an intercostal space is markedly wider and deeper than the others, and is bordered on either side by a slightly thicker and higher rib; there is a tendency, manifested on several of the specimens, for these deeper interspaces to align themselves one above the other on successive volutions, but they may occur anywhere on the shell; the ribs become regularly smaller on the succes­sively smaller volutions and the earliest volution is nearly smooth. On the smaller volutions of the spire bifurcation of the ribs is rare, but this feature is more com­mon on the largest whorl and on the retroversal volution. Two rows of small weak to obscure nodes parallel each other 2 mm. or less apart on the ribs low on the sides of the volutions of the spire; these are practically wanting on the smaller whorls of the holotype and of several of the paratypes, but are present on others; the nodes are elongated in the direction of the ribs, and in places mark the point of bifurcation of ribs; nodes are wanting on the retroversal volution. The sutures are not discernible on the available ma­ terial. The fine, closely crowded ribbing and the weak nodes of this species serve to distinguish it from the other species of N ostoceras. Types.-Holotype, U.S.N.M. no. 77265; 9 unfigured paratypes, U.S.N .M. no. 77266. Distribution in Texas.-Navarro group, Nacatoch sand: 21h miles west by south of Corsicana ( 1 7368) . NOSTOCERAS 1 DRACONIS Stephenaon, n.sp. Pl. 82, figs. 5-9 Shell of medium to large size, coiled in the ephebic stage in a very low spiral with, however, the volutions slightly separated, passing in the gerontic stage into a large, well developed retroversal volution. Um­bilicus wide and shallow. Conch sub­circular in outline, increasing rather rapidly in diameter, and becoming broadly subovate in the larger stages. Surface covered with numerous, rather sharp­crested ribs of nearly uniform size, which pass with slight sinuosity entirely around the shell; these number about 5 to the centimeter on the large end of the holo-. type, increasing to 8 or 9 on the smallest part preserved, but showing some varia­tion in the coarseness of the spacing; oc­casional bifurcations appear, generally at the nodes. There are two rows of round or slightly elongated ventral nodes which vary in size on the holotype from very obscure to quite prominent; the coilinµ: is such that on the larger parts of the shell the upper row of nodes lies at the line of near-contact, some of the nodes actually touching the adjacent volution, causing slight indentations, and the lower row is submerged; toward the apex the shell rises a little and becomes more loosely coiled, so that both rows of nodes are in view, though the nodes are weakly developed here; the upper row of nodes becomes very weak and practically disappears toward the large end of the holotype. One large specimen (17365) , which is believed to belong to this species, includes about the last third of the largest whorl of the spire and all of the retroversal whor 1 (pl. 82, figs. 8, 9) ; a contact groove is present on the inner curve of the conch just before the free stage is reached. The conch increases rapidly in size as it sep­arates from the spire, and becomes mark­edly more coarsely ribbed; the ventral nodes also increase in size, both the nodes and the ribs becoming very coarse and irregular in strength and spacing around the main bend of the retroversal whorl; the nodes quickly fade out on the nearly straight terminal limb of this whorl. One small paratype (16170) forms one com­plete volution representing a younger stage than the youngest part of the incomplete The Unitcrsity of Te.ras Publication No. 4101 holotypt:>: it is rt:>ferrt:>d to this spPcies because of similarity of ribbin!! and simi­larity in degree of .coiling and of spiral flattening: the nodes are weakly den•lu1wd but the two rows are distinguishable. The height of the incomplete spire of tlw holotype i.s 30 ~ mm.. and the maximum diameter of the shell as a whole is 60 mm.: the dorso-wntral diameter of the large end of the conch itself is 22.5 mm.. and the trans,·erse diameter is 2-l mm.: the dia­meter of the smallest part of the shell preserYed is 7 mm. The large retroYersal whorl is subcircular in cross section ran!!­ing in diameter from 25 to 28 mm. 01~e large fragment among the paratypes at­tains a maximum diameter in cross section of 32 mm. Types.-Holotype. LS.:\.~I. no. 7726 7: 1 figured paratype. C .S.\" .\I. no. 77268: 6 unfigured paratypes. LS.\".:\I. no. 77269: 2 unfigured paratypes. r.S.\".M. no. 77270. Distribution in Te.ras.-:\aYarro group. \"eylru1dYille marl: 31 ~ miles west-north­west of Corsicana 06166. holotype and 6 paratypes) : -1 miles west by north of Corsicana f17369) : 21 ~ miles north of Corbet 116170. 2 unfigured paratypes: 17365. 1 large figured paratype: Tex. Bu. 17300 I : ~ Smile north of Cooper (1--1062 L NOSTOCERAS sp. :\ large retrowrsal coiI. including the complete Ii Ying chamber I pl. 81. fig. 13) from the \"edandYille marl on the Dallas highway~ 3 7 10 miles west of Kaufman. Kaufman CountY ~ UlOl '1. is like .Yosto­ceras except tha·t Yentral nodes are want­ing: the ribbing is coarse and. aside from the absence of nodes. is practically iden­tical \\·ith that of .Y. hrntti. C.S.\".\I. no. 77271. Genus ANAKLINOCERAS Stephenson, n.ren. Type :;:. pecie'.-Anal:!inoccras reflc:rum Steph·:-n­ :'nn. Etym11ln~y.-ci1ci, up: ,..\(;u..·. :;}ope again~t ~ KEpas, horn. This IH'W genus is related to .Yostroceras but differs in the growth habit of its gerontic. retnwersal whorl: in all speci­mens completely enough presen·ed this whorl is bent back up the side of the spire. and in sewral of the more complete in­di,·iduals rises to a few millimeters aboYe the apex, where it bends back down over tht~ opposite side of the spire, reaching halfw~1Y to it~ hase, thus embracing the ~pirc' i;1 a sort of incomplete archway. A similar hahit is cxhihitt'd hy the Neo· comian specie~. IIetaoceras emerichi (ffOrhi!!nY) .·1 ~~ which difTers. however. in that th; ~scending retroYersal Yolution dot=>s not hug the spire closely. hut sur­mounts it in a fret=>. nearly circular arch. A similar habit is also seei-i in a group of Aptian species from western Georgia. Transcaucasia. described by Rouchadze-1s9 under the generic and subgeneric names Colchidites (lmerites) Djanelidze. In these an early spiral portion of the shell is encircled by a later adult portion that ranges in the different species from open to closely coiled in one plane; in some of them the spire is only 2 or 3 centimeters high. and nestles within a surrounding adult shell that reaches an over-all diam­eter of 10 to 15 centimeters. The spire of Anaklinoceras is proportionateIy higher and more slender than that of any species of .Yostoceras. except N. colubriformi,s. The shell in its earliest observed stage is free and 1 mm. in diameter, but within a few millimeters it assumes a coiled attitude with an umbilical opening 3 mm. more or less in diameter. The shell is transverselv ribbed as in ·r\'ostoceras. the ribs being ~otably rnriable in strength and spacing on different in· diYiduals. The shell averages smaller than any of the known species of Nostoceras. ANAKLINOCERAS REFLEXUM Stephenson, n.sp. Pl. 83, figs. 1-5 Shell small. with a small uncoiled initial stage of undetermined length, a rather high. closely coiled spiral ephebic stage of 4 to 6 volutions, and a gerontic stage in which the shell is reflected back up one side of the spire to a few millimeters beyond the apex. where it bends oYer and ~xtends about halfway down the opposite side of the spire. In one of the paratype.s (pl. 83~ fig. 5) the shell at its smallest '''[)'(hbigny. ~f. ..\lcidt', J our. Conch. (Paris) 1851, P· ::; 1:-. pl. 3. fi~. 1. 1851. '"\>Roududze. J .. Lt's ..\mmonites .\pt.t'nnes de la G;·tir~ i ·: Occidentalt' : Bull. de L "Inst. c~~ol de Georgie, vol. l. fa sc. 3. pp. ~:>7-~66, pis. 1-l-:2~. 1933. ldt'm, vol. 3, fa:•r. ::;. pp. l83-Ia6, pis. 4-6, 1938. Invertebrate Fossils of the Navarro Group preserved portion is about I mm. in diam­eter, and is bent up free from the volution below for a distance of about 3.5 mm. ; the smallest complete volution is about 5.5 mm. in diameter with an umbilical opening about 3 mm. in diameter. In this shell the second volution is only a little larger than the first, but the next two volutions below expand and enlarge rapidly; there is a rapid increase in size in the early part of the gerontic stage. In another shell the smallest volution is only about 4 mm. in diameter. The shells exhibit considerable individual variation in the diameter of the smallest volution, and in the height of the spire; the sides of the spire diverge at an angle of ap­proximately 45 degrees. Among about 32 specimens complete enough to show the di­rection of coiling of the spire 20 are dextral and 12 sinistral. The rest of the material is fragmental. Ribs are numerous, rather sharp­crested, and are present over the whole of the shell as preserved; they are, how­ever, weak on the earliest stage; in general the ribs are narrower than the interspaces. At widely spaced intervals an interspace is wider and deeper than the intervening ones, and each of these is bordered on either side by a higher more prominent rib; this appears to be a characteristic feature of the species. The ribs on the free gerontic stage are wider apart and more irregular in prominence than on the spire; there is a marked individual varia­tion in the coarseness of the ornamenta­tion; an occasional rib may be added by intercalation or bifurcation; ribs thus added are somewhat more common on the early and middle portions of the gerontic stage. The shell is further or­namented by two rows of small nodes on the venter; these are very weak on the earlier volutions, but increase grad­ually in strength until they become prom­inent on the gerontic stage; the nodes may he present on successive ribs, or one or two unnoded ribs may intervene. The umbilical opening in th~ spire varies in size on different individuals but is small, ranging from 2 to 4 mm. in greatest diameter. The sutures are not clearly ex­posed. Dimensions of the holotype: Total height of shell, including the retroversal volution, 38.7 mm.; diameter of largest volution of spire about 15 mm.; dorso­ventral diameter of large end, which is probably near the aperture, about 13 mm.; transverse diameter at the same place 12 +mm. The largest specimen in the collections, a poorly preserved gerontic whorl, has a height over all of 53 mm.; it has a dorso-ventral diameter of 15 mm., and a transverse diameter of 16 mm. Types.-Holotype, U.S.N.M. no. 77272; 1 figured paratype, U.S.N.M. no. 77273; 1 figured paratype, U.S.N.M. no. 77274; 11 unfigured paratypes (and fragments) , U.S.N.M. no. 77275. Distribution in Texas.-Navarro group, Neylandville marl: ~-12 mile north of Cooper (14062); 2/5 mile north of Cooper ( 14063) ; 21h miles north of Corbet (16170, 1 figured and 11 unfigured paratypes; 17365; Tex. Bu. 17300, holo­type and 1 figured paratype) ; 3 miles northeast of Drane ( 16164). Genus TURRILITES Lamarck TURRILITES SPLENDIDUS Shumard Pl. 82, figs. 1-4 1861. Turrilites splendidus Shumard, Boston Soc. Nat. Hist. Proc., vol. 8, p. 191. 1893. Turrilites splendens Shumard (error in spelling of specific na.me). Boyle, U.S. Geol. Survey Bull. 102, p. 293. Shumard described this species as fol­lows: Shell turreted, spire sinistral and dextral, very much elevated; spiral angle 23 °; volutions about ten, strongly rounded, contiguous; suture deeply excavated; umbilicus small, occupying a very small part of the diameter of the last volution; aperture subcircular. A short distance behind the aperture is a prominent ring, anterior to which the diameter becomes suddenly contracted to the margin; surface elegantly ornamented with prominent rounded, simple and bifurcating ribs, which on the body volution commence at the margin of the umbilicus, and pass in an oblique upward and backward curve, until they get near the suture, where they are suddenly bent forwards. The number of ribs on the last volution varies from twenty-four to twenty-eight, and they are here wider apart and not so regular as on the turns of the spire. Ribs bearing each two small elongated tubercles, one situated near the inferior edge and the other near the middle. The University of Te:ras Publication No. 4101 Length. twcnty-orw linf's: diameter of last Ynlution sewn lin{'s. In form and gcnf'ral ap­pearance this heautiful Turrilite is similar to T. mtcnrrtus. D'Orh.. h11t differs in having a small<'r umbilicus. in the diffen"'nt position of the tuber­cle.... and their smaller size. In a later rollection from near Chat­field. Navarro Counts. are 16 more or less incompkte indi,·iduals (U.S.N.M. no. 21091 ) one of which. in lieu of the ~riginal t)yes, 1s designated neotype. fhe~w spec11nens (topotypes) exhibit no­ticeable differences in form and ornamen­tation. which. however, are probably in­dividual variations. Most of the speci­mens are smaller than the one measured by Shumard, but in one fraoment the t:' diameter of the largest volution is 22.5 mm. ( =nearly 11 lines). If the specimen just mentioned is cor­rectly identified, it shows that the or­namentation b e c o m e s proportionate}y coarser in large individuals, the nodes and costae both being more prominent. With the exception of this one large speci­men the costae and nodes are rather small and fine; the two rows of nodes are low down on the side of the volution, and on some specimens the lower row is at the line of contact between the volutions. or may even be slightly concealed. There may be considerable variation on the s~:une individual in the prominence and spacing of the ribs. At widely spaced interval~ an interspace is deeper and wider than the others, and generally one or both of the. inrlosi1~g ribs are larger, forming vances of chfferent degrees of prominence; the prominent "ring'' described by Shumard is one of these varices. Mo~t of the ribs are simple, but an occasional one Is seen to bifurcate, generally at a node. The spire is high~ and the number of nilutions may be as many as 1-l. or more. ThP diameter of the smallest volution prestrved is 2 mJ1L and it bears a contact groon=-nearly. but not quite, to its end~ the diameter of the smallest part of the conch on this specimen i:;; 0.8 mm.; the uncoiled initial stage, if any, must, there­ fore~ ha,·e been very small and short. Although the larger .volutions are more loo~dy coiled than the earlier ones there Is no indication of an uncoiled senile stagf'. The dimc:.nsions of the neotype are: ll<'ight of inrnmplete spire 32 +mm., :-< (. "'-. \. of this species. the smallf'st of which has minimum diameter of 3 mm. Types.-Shumard's original material is lost: it was collected near Chatfield. \ . aYarro CountY. :\eotype st'lected from four specimens in the rnited State$ :\ational :'.\Iuseum. collected ln-Dr. T. \\". ~:tanton ne3r Chatfield. and identified bY hi~n as H elicocera.s naz·arroen se Shumard. L~..\.'1. no. 77282: 1 figured topotype. L~._\.::\I. no. 77233: 2 unfigured topo­t~· JY's. LS..\.:'.\I. no. 21082: 1 ple$iotypf'. LS._\.:\I. no. 7728-1. D..stribution in Texas.--\-~n-arro grnup. :\e~·Lmd,·ille marl: 21 :..: miles south of Ben Hur f 1.55-13 ·1: 21 :.! miles north of Corbe~ t l 7365·1. :\anrro grouo. :\acatoch sand: YicinitY 1. •f Chr. tfi f'!~l ~ 762. t~-pf' loc. ) : 2I ~ mil~s nnrth of Corsicana t l-111-11: 3 3 IO milr5 west-sn~1thwf'st of Corsicana f 161(>3. fig­ured 1 : ;) milt:'~ iwrtlwa~t of :'.\h-Clanah,~n tl737ll. Ran, :·c. --_\c> ylandYi11 e marl and _\a ca­tnd1 S[.nd of .\m-arro group. HELICOCERAS? sp. _.\ ::"ma I l riblwd fragnh~nt with a double rnw of nnl1e~. from tl;e _\p, land,·ille marl un thC' DalL1 s Hip-hway. 2.i ~ miles north­ea~t of Ron·,""' Cit\·. in Cullin Count,­1 1 (d .=) 71. 1~ quc~t-ion~bh-referred t~ Ifelico('t>ras. l-..;. Y \I . --.)n­ -·~.. _' ._ . no. , , -l)u. F3rnily DE~:\IOCER.\TID.\E Genus PARAPACHYDISCUS Hyatt The slwll~ here referred to Parapachy­di5cu s were commonly referred to Pach y­tfigus Zittt:>l prior to the introduction of the former name ln-H,·att in the first Enp-lish editinn of Zittcl's Text-Book of PalenntPln~Y of 1900. Hyatt designated Ammonites ~ollei·ilI en sis D~Orbigny490 t = .-1 m monites le1resiensis D"Orbigny, not ~owcrln) a~ tlw t!e110tqw.·t\)l This species is from. the l'ppcr Chalk (Senonian) of Franee. En~Lrnd. and other countries. PARAPACHYDISCUS ARKANSANUS Stephenson, n.sp. Pl. 8 L pl. 8;). fig~. 1-3: pl. 86, figs. 1-5; pl. 87. fig~. 1-3 ~hell of medium size. strongly involute; sidc>s slightly flattened. di,·erging a little inwardh·: wnter broadh-arched. Umbil­icus d~ep and of ;noderate width; umbilical shoulder rather sharply rounded, descending steeply into the umbilicus. The li,·ing chamber is not presen·ed on the few aYailable spPcimens. A shallow, \ Pntral grooYe 1 to 1.5 mm. wide on the internal'mold reflects the siphuncle which immediateh-underlies the wntral surface. Surface or;rnmented with somewhat rnri· ahle. moderatel,-strong. rounded ribs spaced at interY~lls of -i'-to 13 mm.; the rihs number about -10 on the largest volu­tion of tlw holotypc. The ribs on the Yotm~er stages show a tendency to de­~ elo1; elong~te nodes on the umbilical shoulder. but these nodes become obscure on the larger stages. The ribs curve slid1th backward 0;1 the shoulder, become nP~rh. direct to the middle of the side, nnd finalh· curn•. sli~hth· forward as they pas:"-up .oY~r tht.~ \.en.tn~ indicating a ~li~ht \·f'ntral erf'st. The sutures are de~ply and intricately digitate. The siphonal lobe is deep and narrow with slender lateral branches which increase in sizP and intricacy posteriorly; the Yentral saddle is about two-fifths as high as tht> lohe i~ dN'P: it is proportionately l1road. blunt a11d cauliflower-like. The elaborateh· dendritic laterd saddles and lt)bes dec;.ease in size rapidly toward the lim~ of inYolution: the saddles are pro· portionately broad and the lobes very slPnder and sharply digitate; there are 4 !•.'tYOrLi~ny, Alci1le, PwJrume J ,-Palcontologie, ,·ol. 2, I'· ::;1::;. 18~0. 4\0.:D"Orbigny. :\lei de. P.i lt~on tologic Fn:H;aise, Descrip. d,' s :\nimaux Imcrt.: Terra!in Cretare, tome I, G rhalorc>Jc~. r. 3~6. pl. l et pl. ~. figs. I. ::?, 18H. Invertebrate Fossils of the Navarro Group four lateral saddles, the fourth one fol­lowed by several small saddles which form the outer side of a moderately deep hanging lobe at the line of involution. Maximum diameter of the holotype approximately 183 mm.; maximum radius from the center of the umbilicus to the venter 113 mm.; maximum dorso-ventral diameter 95 mm., and corresponding transverse diameter 75 mm. The description is based on the holotype which is from the Nacatoch sand of Arkansas. The Texas material identified with this species consists of four incom­plete young individuals, the largest and most complete of which has a maximum diameter of 82.3 mm., a maximum radial diameter of 49 mm., a maximum dorso­ventral diameter of 46.7 mm., a cor­responding transverse diameter (measured between the ribs) of 42.8 mm., and a maximum umbilical diameter of 21 mm. In its early stages the conch is plumply rounded, the cross section from one line of involution to the other describing a nearly circular curvature; the flattening of the sides takes place gradually as the older stages are reached. The growth lines are curved backward on the umbilical shoulder, straighten out above, and pass nearly directly up over the venter, with a faint suggestion of a crest in the older stages. The ribs number 37 around the venter, and of these 13 are primaries originating on the umbilical shoulder, and the remaining 24 are secondaries arising on the sides of the shell either indepen­dently in the interspaces between the pri­maries, or by the dividing of the primaries; 9 of the primary ribs hear moderate! y prominent, but unequal, shoulder nodes which are elongated along the crests of the ribs. In the earIy stages the ribs pass from the sides directly upward over the venter, but in the later stages they curve gently forward on the venter. On a less complete Texas specimen, which has a transverse diameter of about 34 mm., the sutures are well exposed, and are essentially like those on the larger holotype. The blunt upper end of the ventral saddle is rendered trifid by two small slender digitations pointing directly backward; the central subsaddle thus produced is divided by a small rela­tively broad, shallow, blunt-ended minor lobe. The antisi phonal lobe is about half as deep as the siphonal lobe; it widens a little downward and is trifid below; be­tween the antisiphonal lobe and the line of involution are three narrow, dorsal saddles which decrease somewhat in size outwardly, and are separated by two slender lobes; the outer side of the third saddle forms the inner side of the hanging lobe on the line of involution. Types.-Holotype, U.S.N.M. no. 77286, Old Military Road, 2 1/8 miles northeast of Washington, Hempstead County, Arkan­sas (7472). Paratypes from Texas, U.S. N.M. nos. 21094, 20962. Distribution in Texas.-Navarro group, Neylandville marl: 3 7/10 miles west of Kaufman (17119). Navarro group, N acatoch sand: Vicinity of Kaufman ( 761, figured) ; field 3/5 mile west of Kaufman ( 14103) ; vicinity of Chatfield (762, figured) ; 3 1/5 miles north of Corsicana (16168). Outside distribution.-Arkansas: Naca­toch sand (includes type loc.) . Range.-Neylandville marl and Naca­toch sand of the Navarro group. P ARAPACHYDISCUS SCOTTI Stephenson, n.sp. Pl. 88 Shell very large, plump, strongly in­volute; sides plumply rounded in the younger stages, becoming slightly flattened in the older stages. Umbilicus deep and wide; shoulder rounding down steep] y into the umbilical depression. The last volu­tion, including the living chamber, is im­perfect, part of it having been broken before fossilization, and a considerable part of the surface having been hadly cor­roded by weathering; the rest of the shell, though considerably broken, is fairly well preserved, with the exception of the very small, early stages. A cross section of the shell (reduced in reproduction), drawn where the diameter is about 39 centimeters, is given in text figure 11. The growth lines trend sharply hack from the line of involu­tion, curve forward to a nearly direct radial direction on the umbilical shoulder, extend with slight sinuosity to the middle of the side, and curve moderately forward as they pass over the venter, forming a noticeable crest. The surface of all but the living chamber is ornamented with low, The University of Te:ras Publication No. 4101 ,,,,,,,,,......------......... , ,, ,/ ,, ,, I I \ ' ' ' \ \ I \ I \ I \ I I \ \ I I \ \ I ,i I \ ' I I ,• I I I I•• I I I I I I I I I I I' I I I I I n thr ugh th cotti rounoeCI rib s of somewhat unequal devel­opment, separated by interspaces 2 to 5 times the width of the ribs; the interspaces increase in width very gradually in the forward direction from a minimum of 3 mm. or less to a maximum of 25 mm. or more; the ribs are approximately parallel to the growth lines. The ribs that originate on the shoulder may be regarded as pri­mariC's, hut m1mrrous secondaries arise on the ~idC's at different distances from the shouldPr. In the early stages up to that at which the transverse diameter is about ,,10 mm. the ribs tend to form elongated nodes just outside the shoulder, the largest nodes being just back of the diameter men­tioned; on all larger stages nodes are ob­scure or vrnnting. The living chamber lacks the small ribs just described, but is ornamented with a few large, low, broad undulations each of which is strongest just outside the shoulder,. gradually diminish­ing in strength outwardly and dying out before reaching the venter. The sutures shown in text figure 12 were drawn from a fragment examined before the specimen was reconstructed; it was necessary to grind off the shell in order to expose the suture lines. The dorso· ventral diameter where the sutures were uncoYered is 87 mm., and the transverse diameter approximately the same. The lobes and saddles are profound and are intricately digitate. The siphonal lobe has a depth of 62 mm. There are 4 lateral saddles between the venter and the line of involution; these are relatively of mod­erate width and decrease rapidly in size inwardly. The saddles are separated by slender, intricately branching, sharply digitate lobes. The inner side of the fourth lateral saddle forms the outer side of a hanging lobe on the line of involution, whose depth is about 14 mm. The ventral saddle is of cauliflower-like pattern and is approximately two-fifths as high as the total depth of the siphonal lobe. The dorsal lobes and saddles are not as well preserved as those outside the line of in­volution; there are three slender saddles which increase in size from the line of involution toward the dorsum; the lobes are slender and the antisiphonal lobe ap· pears to be about 27 mm. deep; the outer side of the outermost dorsal saddle forms the inner side of the hanging lobe on the line of involution. The diameter of the largest part of the last volution that can be accurately measured is 51 + centimeters (several millimeters corroded from venter on one side) . The widest measurable part of the ~ ~ ~ "i C""to ~ O"' "i ~ C""to ~ ~ c ~ ~ ~. C:--.0 ~ c '-... C""to ~ ~ ~ ~ ~ ~ "i c ~ "i c .§ ~ N> ~ The Unii-ersity of Te.tas Publication No. 4101 umbilicus is 17.3 centimeters. The ~realest nwasurable dorso-Yentral diameter ts about 23 centimeters~ and the correspondinp; transwrse diameter is approximately 20 centimeters. This species resembles Parapachydiscus arkansanus in a general way. but the dorso­Yentral and transYerse diameters are ob­Yiously more nearly equaL and this dif­ference continues throughout the largPr stages. The ribbing is similar in the two species and the sutures are alike in all essential features. Holotype.-r.S.:\.lH. no. 77287. Named in honor of the collector, Dr. Gayle Scott. Distribution in Texas.-~aYarro group, :\acatoch sand: :\ear Corsicana U7012). Unidentified specimens of PARAPACHYDISCUS One small internal ammonite mold found in the :\edandYille marl in a road­side ditch 21 :.! ;niles south of Ben Hur, Limestone County l155-13), probably be­longs to an undescribed species, but is too immature and too poorly presen·ed to serYe as a type. The shell is plumply rounded and has a maximum diameter of 6 mm.: the dorso-wntral diameter is less than the transYerse diameter, the dimen5ions being approximately 2.5 and 3 mm. respectiYely. \'o ribs are apparent at thi~ stage. FS."\.l\I. no. 77288. A fragment of a Yotmg stage of Parapachydiscus from the Nacatoch sand on L.S. Highway 75, 4 miles north of the courthouse at Corsicana, l\aYarro County 1 l 7366). is too incomplete and too im­mature for satisfactory identification. It i~ plump and the sutures are well pre­~erYed. LS.:\.:\I. no. 77289. F;.unily COS~IOCER:\TID_.\E Genus AXONOCERAS Stephenson, n.gen. Type ::-pt•cies.--Axunoceras compresswn Stephen­son. Et~ m11l11~y.--ci~·t~·1·. a wheel; t\ipa'>~ a horn. The ammonites included in this new gen us. Axonoceras~ are long slender shells coiled in one plane. with numerous closely spaced rib:' and two rows of Yentral nodes. The initial coil is hoop-like with an umbilical perforation 3 to 5 nun. in diam­der. The shells may be closely coiled, thour-o-h not inYol ute. . but most of them are more or It~ss loose!y and irregularly <'oiled. Partial mH:oiling or humping of the c011ch away from the inclosed volu­tion may take .plal'e in any of the volu. tions and nw\ mTtir al 2 or 3 stages in the growth of an individual; where this uncoiling OlTurs the free part of the conch comes back again to join the in· closed Yolution in less than half a turn. The humping is common in the gerontic stage. where the width of the opening sep­arating the Yolutions may reach 3 mm.; in this case death may prevent the conch from bending in again to meet the in· closed volution. The uncoiling is more conunon and more pronounced among the shells of Axonoceras compresswn than it is among the other species of the genus. This habit of growth is suggestive of that seen in Scaphites and Ancyloceras, but is less constant with respect to the magni­tude of the humping and the part of the shell affected. Axonoceras is similar in form and habit of coiling to the Neocomian genus, Crioceras Leveille, but is consistently more closely coiled in all of the numerous shells here referred to it. Representatives of the genus have been found only in the Neylandville marl in Navarro and Delta counties, Texas. AXONOCERAS COMPRESSUM Stephenson, n.sp. Pl. 89, fig~. 1-5 Shell small, slender, coiled in one plane. The smallest stage of the conch obserYed is less than half a millimeter in diameter and is probably near the proto· conch. The first volution is an open hoop-like coil with an umbilical perfora· tion 3 to 5 mm. in diameter. The first 2 or 3 volutions are generally more or less closely coiled though partial uncoil­ing, or loose coiling may take place at any stage; in the holotype the first in· dication of loose coiling appears in the earliest third of the initial coil and pro· nounced uncoiling affects the latest coil at two places. The most pronounced humping generally takes place in the gerontic stage, as seen in the paratype illustrated in plate 89, figure 4; but in Invertebrate Fossils of the Navarro Group some individuals there is scarcely any humping at any stage, as exemplified in the paratype shown in plate 89, figure 3. The greatest observed gape caused by the partial uncoiling is 3 mm. wide. In the early stages the shell is circular in cross section, but in the later stages, it becomes compressed on the sides, thus producing a subrectangular cross section. In the adult stage the do rs um becomes decided! y flat­tened. The sutures are not well enough exposed for description. The surface is covered with numerous sharply rounded, somewhat variable ribs; on the smallest stage the ribs may number as many as 4 to the millimeter, but they gradually become fewer until on the gerontic stage they may not exceed 8 or 9 to the centi­meter; the ribs become weak where they cross the dorsum, or may even fade out complete! y there; they are nearly as strong on the venter as on the sides. The \'enter bears two rows of nodes which in­crease in prominence toward the aper­ture; the pairs of nodes are present on most of the ribs, but an occasional rib or even two adjacent ribs, may be nodeless, especially on the larger stages; the nodes are circular in cross section. The greatest diameter of the coiled holo­type is about 17 .5 mm.; the small end of the conch, as preserved, is less than half a millimeter in diameter; the large end of the conch is about 5 mm. in its dorso-ventral diameter and 4.5 mm. in its transverse diameter. The dorso-ventral diameter of the largest fragment in the collection is 10. 7 mm. Types.-Hoiotype, U.S.N.M. no. 77290; 1 figured paratype, U.S.N.M. no. 77291; 1 figured paratype, U .S.N .M. no. 77292; 1 figured paratype, U.S.N.M. no. 77293; 1 unfigured paratype, U.S.N.M. no. 77294; 8 unfigured paratypes and numer­ous fragments, U.S.N .M. no. 77295; 5 unfigured paratypes and numerous frag­ments, U.S.N .M. no. 77296.. Distribution in Texas.-Navarro group, Neylandville marl: 21;2 miles north of Corbet (16170, 8 +paratypes, 1 figured; 17365, holotype and 5 + paratypes, 1 fig­ured; Tex. Bu. 17300, 1 figured para· type); cut of Texas Midland Railroad, ¥2 mile north of Cooper ( 14062, 1 unfig· ured paratype). AXONOCERAS PINGUE Stephenson, n.sp. Pl. 89, figs. 6-8 This species is similar to, and is a close ~ela ti ve of, Axonoceras com pressum but is larger, plumper on the sides, and lacks the pronounced humping of the gerontic portion of the shell; in the gerontic stage there is only a slight tendency for the shell to uncoil. On the smallest stage preserved the ribbing is of about the same degree of fineness as on com pressum, and relatively fine ribbing continues to the beginning of the gerontic stage, where the sculpture becomes markedly coarse; on the large end of the conch the ribs may number as few as 5 to the centimeter· on the gerontic portion there is a tend~ncv for the ribs to alternate in size. Th~ ventral nodes are weakly developed on all but the gerontic shell where they become strong and coarse, and with occasional e~ceptions the pairs occupy every other nb; the nodes are circular in cross section. . Dimensions of the holotype: Greatest diameter 27 mm.; maximum dorso-ventral diameter 8.5 mm.; maximum transverse diameter 9. 7 mm.; diameter of the small­est stage preserved 1.2 mm. Types.-Hoiotype, U.S.N.M. no. 77297; 1 figured paratype, U.S.N.M. no. 77298; 25 unfigured, incomplete and fragmentarv paratypes, U.S.N.M. no. 77299. · Distrib~tion in T exas.-Navarro group, Neylandville marl: 27'2 miles north of Corbet ( 16170, paratypes; 17365; Tex. Bu. 17300, holotype and 1 figured para­type). AXONOCERAS MULTICOST.ATUM Stephenson, n.sp. Pl. 89, figs. 9-11 Shell small, slender, coiled in one plane. The smallest stage is an open coil with an umbilical perforation about 2.8 mm. in diameter. The small broken end of the ~one?, which must be near the initial stage, is slightly less than half a millimeter in diameter. The 3 volutions are closely coiled except toward the large end of the conch where the gerontic stage shows a The Uniz·ersity of Te:i~as Publication No. 4101 slight tendency to become humpNl. In the first two Yolutions the> cross section of the shell is nearly circular but the largest Yolution becomes slightly compressed. The surface oYer all but a few millimeters of length at the small end of the shell is coYered with numerous fine~ narrow, sharply round-crested ribs of irregular ~trength and spacing, which cross the wnter without marked change in size; an occasional interspace is noticeably wider than the others; on the venter at the large end the ribs number about 13 to the centi­meter. The venter is flattened and bears two rows of small nodes, the pairs of which may occupy either every rib or every other rib; these nodes are slightly flattened laterally and are smaller and more num­erous than those on Axonoceras com pres­sum, and the rows are proportionately closer together. Dimensions of the holotype: Greatest diameter of the coiled shell 19.5 mm.; maximum dorso-ventral diameter 6.5 mm.; maximum transverse diameter 6 mm. Holot_ype.-U.S.N.1\1. no. 77300; 8 un­figured incomplete and fragmentary para­types, U.S.N.M. no. 77301. Distribution in Texas.-Navarro group, Neylanddlle marl: 21h miles north of Co~bet l Tex. Bu. 1730( holotype; 17365, paratypes) . AXONOCERAS MULTICOSTATUM ROTUNDUM Stephenson, n.var. Pl. 89, figs. 12-U Shell small, slender, coiled in one plane. The early stages are wanting, the smallest diameter of the conch in the available material being 3 mm. Although not seen in a sufficiently complete speci­men. the holotype suggests close coiling of the ,-olutions. A contact groove is present on the dorsum of some fragments. In the earlier stages the cross section of the shell is nearly circular, but becomes slight!y compressed on the sides in the later stages; the venter is broadly rounded except toward the large end where it be­comes slightly flattened, and the dorsum becomes flattened in the later stages. Sur­face covered with numerous, closely spaced~ sharply rounded costae which number 9 or I 0 to the centimeter on the large end of the shell~ and about 20 to the centimeter on the fragment whose smallest diameter is 3 mm. The costae lwrnme weak or disappear on the flattened dorsum. l lere and there a new rib is intC'rcalated low on the side. The venter bears two rows of weak nodes which be­come a little stronger toward the aper­ture. The nodes are slightly elongated laterally and may be present either on successive costae or on alternate costae. The sutures are rather poorly exposed on one medium sized fragment; they include six saddles and six lobes. The ventral lobe is of medium width, rather deep, and is rendered bipartite by a low, broad, saddle whose squarish top is slightly wavy. The first lateral saddle is large, broad, moderateIy digitate, and is divided centrally by a small narrow sublobe; each of the subsaddles thus formed is bipartite. The first lateral lobe is deep and is much narrower than the first lateral saddle; it is moderately digitate. The second lateral saddle is similar in size and outline to the first. The second lateral lobe is similar to the first, but is smaller. The dorsal saddle is small and moderately digitate. The antisiphonal lobe is small, narrow, and only slightly digitate. Dimensions of the holotype: Maximum dorso-ventral diameter, 7.5 mm.; maxi· mum transverse diameter 7.6 mm.; cor· responding dimensions of the small end 4.7 mm. and 4.3 mm. Maximum diameter of the coiled shell 24 mm. This variety differs from the typical species in its greater plumpness, its more rounded venter, and the much weaker development of the \'entral nodes. Types.--Holotype, U.S.N.M. no. 77302; 5 unfigured par at y p es (fragments), U.S.N.M. no. 77303. Distribution in Texas.-Navarro group, Neylandville marl: 2V:.! miles north of Corbet (16170, type loc.) ; 1/2 mile north of Cooper (14062). AXONOCERAS? sp. A small fragment of an ammonite shell questionably representing the young stage of Axonoceras is recorded from the Naca· toch sand in a public road cut east of the Houston & Texas Central R.R. near a Invertebrate Fossils of the Navarro Group section house, 21h miles north of Cor­sicana, Navarro County ( 14114) . The specimen is about 6 mm. long and is nearly circular in cross section, having minimum and maximum diameters of 1.5 and 2 mm. The shell is ornamented with about 15 rather weak, rounded, annular ribs with two marked constrictions about 4 mm. apart. U.S.N.M. no. 77304. Family SCAPHITIDAE Much uncertainty exists as to the family relationships of the Scaphites-like am­monites. Difficulty is experienced in determining criteria that can he relied upon in making the family assignments. Neither differences in form, in suture pat­tern, nor in ornamentation have proved wholly satisfactory as criteria, when the group is considered as a whole. Even Reeside"92 who, as late as 1927, attempted to ref er the known species of the group to one or other of the families Stepheo­ceratidae ( = Stephanoceratidae) , Desmo­ceratidae, and Cosmoceratidae, n o w states498 that he is not satisfied with the classification suggested in the paper cited. In view of the existing unsettled state of knowledge of this group it seems con­venient, for the present at least, to con­tinue grouping the genera under the old family heading Scaphitidae. Cenua SCAPHITES Parkinaon, senau lato The species here included under Scaphites would, according to Reeside's494 1927 classification, he referred to Acanthoscaphites Now a k.495 Nowak's genus is founded on Scaphites tridens Kner, which is characterized by a central row of strong ventral nodes in addition to the two rows of marginal ventral nodes. Assuming that the typical Acanthoscaphites is a valid genus, the total absence of a central row of ventral nodes on the Amer­ican species here under consideration Mlfteeaide, 1. B., U. S. Geol. Survey Prof. Paper 150-B, pp. 21·40, pl1. 9-11, 1927. -Oral communication. *Reeeide, 1. B., U. S. Geol. Survey Prof. Paper 150-B, pp. 21·40, pl1. 9-11, 1927. MINowak, Jan, Unterauchungen uber die Cephalopoden der oberen Kreide in Pol"'n• pt. 2, Die Skaphiten: Acad. IOI. Cracovie Bull. intemat., annee, 1er. B, p. 570, pl. 32, ... ': pl. 33, 611. 27, 29, 1912. would seem to afford reasonable grounds for doubting the correctness of their reference to that genus. For the present they will be retained under Scaphites. SCAPHITES RUGOSUS Stephenson, n.sp. Pl. 89, figs. 15-18 Shell of medium size, plump, with ventrodorsal diameter shorter than the transverse diameter, closely but somewhat irreg?larly involute in the early stages, openmg out moderately in the last volu­tion. The umbilicus in the early involute stage is small and deep. At least 4 Scaphites-like stages are developed in a single individual. The first two stages may be seen in the young specimen shown in plate 89, figure 18, which exhibits two distinct straightening-out and doubling­back stages in its largest volution; in large shells these first two stages are almost completely enveloped by the later stages. The third stage appears in the first half of the last volution of the holotype; the conch shows a distinct subangulation in trend just below the overhanging aperture, beyond which the conch becomes notice­ably straighter. The fourth stage is that represented by the living chamber, which presents the usual Scaphites-like form, with the outer portion of the conch free, but doubling hack again toward the in­closed volution. The living chamber be­comes noticeably constricted near the aperture. The venter is wide and is flat­tened down to a very broad arch. The surface is ornamented with narrow sharply rounded ribs of variable strength, sep­arated by pronounced, much wider, broadly concave inters paces; the ribs curve slightly forward as they cross the venter. Less than half of the ribs are primaries originating within the umbilicus; the secondaries originate either by subdivision on the flanks or at nodes, or independent! y on the flanks within the interspaces. On the early stages the ribs cross the shell nearly directJy though with a slight for­ward curve on the side; toward the aperture of adults they become inclined strongly forward. There are two widely separated rows of marginal ventral nodes which are rather distant! y spaced; the nodes surmount ribs which may be sep­arated by one, two, three or four unnoded ribs; the nodes gradually increase in size becominµ quilt' coarse on the middle of the liYing diamber. beyond which toward the apt:>rture they lwct.>me gradually smaller again. A similar row of nodes surmounts the urnbil ical shoulder: these may or may not show elongation along the crest of the ribs. Only small glimpses can be had of the sutures. The liYing chamber takes up ahout 0. 7 of the length of the last yo}ution. The maximum diameter of the holotype is 7() mm. The outer three-fifths of the li,·in~ chamber is mechanically crushed but the aperture does not app.ear to be serious! y distorted: here the dorso-wntral diameter is about 32 mm. and the cor­responding transYerse diameter about 36 mm. This species is closely related to Scaplzites nodosus Owen;Hrn from the Pierre shale of the ·western Interior. The holotype of Owen s species is lost. Com· pared with his original figure the straightened portion of the liYing chamber of S. rugosus is shorter, the dorso-Yentral diameter is shorter~ the space between the inner row of nodes and the umbilicus is much narrom.~r, and the sculpture is in general coarser and more rugged. Com­pared with Scaplzites nodosus quadran­gularis ~leek and Hayden;rn7 S. rugosus is similar in the degree of coiling but is much thicker in the direction of the trans­n·rse diameter and is much more coarsely sculptured. The type lot includes three adults. all more or less crushed. and two young indiYiduals. , Types.-Holotype~ V.S . .\.:\I. no. 77305; l figured paratype~ U.S . .\.:\I. no. Ti306; 3 unfigured paratypes~ C.S . .\.l\L no. 21113. Distribution in Texas.-_\ayarro group, .\edandYille marl: '?2L~> miles south of Be;1 Hur 1155-13 l : '? 2~ ~ miles north of Corbet t_Tex. Bu. 17300). .\arnrro group~ :\acatoch sand: 4~·~ mile~ east by north of Rosali l1-1-061) ; Yicinity uf Chatfield l 762, type loc.). Ou!side distribution.-Arkansas: N aca­toch sand I a young indiYidual, 7-1-70). Range.-Questionably in the .Neyland­Yille marl of Texas and in the ~acatoch sand of Texas and Arkansas. .titt~...Owt'n, D. D.~ Rt-:.pt. t•. S. GeoL Sur\'ey Iowa, \\ i·con;in. a11J ~linnt'sota. p . 581, tab. 8, fig. -1, 1852. w7~fn-k. F. B .. Rt·pt. l". S. Ge:.11. Suncy Terr., ,-ol. 9, p. 1::8, iii. ~). tig~. 3..1-i:, 1876. SCAPHITES BREVIS Meek Pl. 90, figs. 7, 8 1876. S1·aphitcs 11odos11s var. brci~is l\Ieek, Rept. l ~ .~. Ceol. Survey Terr., vol. 9, p. 426, pl. 25, figs. la--c. 1880. Scaphites rwdosus var. bre11is Meek. Whitfidd, Rept. Black Hills of Dakota, p. 4--13, pl. 13, figs. 8, 9. 1898. Scaphitcs 11odosu.s var. breris. Meek. Logan~ Univ. Geol. Suney Kansas, vol. 4, p. Sll, pl. 108, fig. 3. ?1905. Scaphites nodosus var. brevis Meek. Smith, lour. Geology, vol. 13, no. 7, p. 6-1-0, text fig. 1 on p. 641, nos. 2, 4-7, 9-18; fig. 3 on p. 645, HOS. 1-3, 5, 6, 9. 1910. Scaphites rwdosus var. brevis Meek. Grabau and Shimer, North American Index Fos3ils, vol. 2, p. 177, fig. 1428. One incomplete crushed internal mold from the Nacatoch sand exhibits sculpture which appears to be essentially identical with the shell which Meek described under the name Scaphites nodosus var. brevi.s. The compressed form of Meek's holotype, together with the fineness of its sculpture, amply justifies raising it to the rank of species. The Texas specimen is an adult smaller than Meek's type. It includes all of the living chamber and two of the septal chambers badly crushed. The ribbing is Yery fine and the ventral and umbilical nodes are well developed and essentially like those on the type. Types.-Hoiotype, U.S.N.M. no. 367, from the upper part of the Pierre shale on Yellowstone River, '"150 miles above its mouth" (near Glendive, Montana). Plesio­type from Texas, U.S.N.M. no. 77307. Distribution in Texas.-Navarro group, Nacatoch sand: 4~~ miles east by north of Rosali (14061). Outside distribution.-"restern Interior, upper part of Pierre shale. Range.-Known in Texas only from the one locality in the Nacatoch sand. Com· mon in the upper part of the Pierre shale of the Western Interior. SCAPHITES PUMILUS Stephenson, n.sp. PI. 90, figs. 10-12 Shell small, closely coiled, and plumply rounded in early stages, straightening out and becoming strongI y flattened on the sides and on the venter in the living cham· her; the flattened sides diverge a little inwardly. Umbilicus small and deep, the Invertebrate Fossils of the Navarro Group maximum diameter to the beginning of the free living chamber being 4 mm. Four volutions can be counted back of the liv­ing chamber. The shell is incomplete at the aperture. The sides of the living chamber are flattened, becoming slightly concave in an undulating fashion toward the large end; the venter is almost flat on the living chamber, and makes nearly a right angle with the sides. The living chamber is quadrangular in cross section; it expands rapidly toward the aperture, and the dorsum becomes very broad and flat on the free portion. The surface of the exposed portion of the shell back of the living chamber is covered with low, narrow ribs of only moderate strength, separated by broader interspaces with broadly con­cave bottoms; the ribs run nearly direct Iy up over the venter, with, however, a very gentle curvature toward the front. Of the 37 ribs that can be counted only 7 or 8 originate at the umbilical shoulder as primaries, all the others arising on the sides by forking or by intercalation in the inters paces. A few rather coarse, elon­gated, widely spaced nodes appear on primary ribs at the umbilical shoulder; back of the living chamber ventral nodes are wanting or only feebly developed. A row of 7 or 8 feebly developed nodes appears on the flanks of the larger part of the volution immediately posterior to the living chamber; these nodes fade out both posteriorly and anteriorly; they appear to be too low down on the sides to represent the continuation of the ventral nodes backward from the living chamber. Two rows of strong ventral nodes are present on the living chamber, ornamenting the angles separating the flattened venter from the flattened sides; these are slightly elongated in the linear direction of the shell. Except for the ventral nodes and the nodes on the umbilical shoulder the sur­face of the living chamber is smooth. The suture of the fourth septum back of the living chamber is well exposed on one side from the venter to and slightly over the umbilical shoulder. The ventral lobe is large and broad and is divided below by a broad, blunt ventral saddle which rises about three-tenths as high as the lobe is deep ; there are 4 branches on either side of the ventral lobe, the two lower ones bifid, and the two upper ones short and simple. The first lateral saddle is broad and large, and is divided above by a short, trifid sublobe. The first lateral lobe is much smaller than the ventral lobe and is bifid below, with all digitations rounded on their ends. The second lateral saddle is bifid and is much smaller and simoler than the first. The second lateral lobe is small and trifid. The third lateral saddle is small and simply bifid. Two more lateral lobes and two more saddles are small and quite simple. The greatest diameter of the shell is 31 mm.; the diameter just posterior to the living chamber is 19 mm. The greatest measurable dorso-ventral diameter is 13.5 mm., and the greatest transverse diameter is 15.6 mm. The species appears to be closely related to Scaphites nodusus var. quadrangularis Meek498 from the upper part of the Fort Pierre group in the Western Interior, but the small size, the smooth flat sides diverg­ing inwardly, the smooth flat venter, and the row of obscure lateral nodes, on the Texas specimen, would seem to warrant its recognition as a separate species. There is some reason to suspect that this may be a dwarfed individual of some larger form. Holotype.-V.S.N.M. no. 21041. Distribution in Texas.-Navarro group, N acatoch sand: Vicinity of Chatfield (762). SCAPHITES YORKENSIS Stephenson, n.sp. Pl. 90, fig. 9 This species is based on a single in­complete mold of the exterior. The shell is of medium size and is mechanically flattened on the side in the one available specimen; the undeformed shell was prob­ably moderately stout and, in lateral view, it is broadly subovate in outline. Um­bilical shoulder of straight part of shell slightly concave inward. Aperture con­stricted. Earlier whorls not seen. Back of the living chamber the coiled part of the shell as far as exposed shows irregular umbilical ribs which divide one or more times on the flanks. There are four rows of conical nodes, two appearing on the last half of the last septate whorl, one about one-fourth the way out from the 498Meek, F. B., Rept. U. S. Geol. Survey Terr., vol. 9, p. 428, pl. 25, figs. 2a-c, 3a-c, and 4, 1876. The Univcl'sity of Texas Publication No. 4101 umhilicus and another ahout the middle of the flank: tlw third, which is pres~nt three-fourths of the way out from the um­bilicus. and the fourth on the ventro-lateral margin, arc already present at the begin­ning of the last septate whorl. On the living chamber the nodes of the inner row have moved to the umbilical shoulder and become large, those of the two median lateral rows disappear, and the ventro­lateral row is conspicuous. The living chamber is covered with fine, even, thread­iike ribs. mostly simple, but a few bifur­cated. There appears to have been no swelling of the living chamber. The sutures are unknown. The species is char­acterized by the four rows of nodes on the septate part, and by the two rows of conspicuous nodes and the fine distinct ribs on the living chamber. The estimated dimensions of the shell are: Maximum diameter 65 mm., minimum diameter between 55 and 60 mm. Other dimensions can not be accurate! y measured. Holotype.--U.S.N.M. no. 77308. Distribution in Texas.-Navarro group, Kemp clay: Near York Creek 4 miles southeast of Zorn (10877). SCAPHITES sp. One fragment of the living chamber of a large individual of Scaphites, from Live­oak Creek at the north edge of Corsicana, Navarro County (518), is specifically un­identifiable, but does not appear to belong to any of the species described above. The fragment is characterized by a row of strong, sharp nodes, which appears to be 'rell down on the side below the margin of the venter. U .S.N .M. no. 77309. Genus DISCOSCAPHITES Meek DISCOSCAPHITES ROANENSIS Stephenson, n. sp. PL 90, figs. 1-4 Shell of medium size, involute, strongly compressed on the sides. Umbilicus small and deep. Posterior to the living chamber the coiling is nearly regular; the living chamber straightens out somewhat, ex­pands rapidly in the dorso-ventral dia­meter, is onl)' moderately elonrrated and . 0 ' m the humped portion toward the aperture scarcely rises free from the preceding volution. In the holotype, which is broken across the center, 5 volutions can be counted back of the living chamber. Ven. ter narrow and flattened. The surface is ornamented with numerous low rounded radiating ribs which curve noticeably for. ward on the venter where, however, they become obscure, or may even be entirely wanting; on the anterior portion of the living chamber the ribs become strongly oblique in the forward direction. In the adult only 9 or 10 of the 30 or more ribs originate at the umbilical shoulder as primaries, the others arising on the flanks at different distances from the shoulder, either by forking or by intercalation in the interspaces. On the living chamber the surface tends to smooth out, passing into a series of low, widely spaced, broadly rounded undulations which differ markedly in streng.th on the same and on different individuals. The venter is bordered on each margin by a row of small, closely spaced nodes of fairly uniform size and spacing; although many of these nodes occupy positions corresponding to ribs, many of them are entire! y independent of the ribs, and tend to maintain uniformity of spacing independent! y of the irregulari· ties in rib spacing. These nodes extend well back on the shell but appear to he wanting on the first 2 or 3 volutions. A row of proportionately coarse nodes is present on the umbilical shoulder where they surmount most of the primary ribs, and become coarser· toward the aperture. On the holotype 3 rows of lateral nodes are easily recognized on each side of the shell and a fourth inner row is represented by several very obscure nodes; there is great variation in the strength of development of these lateral nodes on different individ· uals, but in general the row nearest the venter is the most strongly and most regularly developed and other rows be· come progressively weaker inwardly toward the umbilical shoulder; the two inner rows are generally obscure, and may be practically wanting. The external suture includes 6 saddles and 6 lobes. The ventral lobe of the suture is proportionately narrow and only mod· erately deep and moderately digitate; the ventral saddle is broad, blunt-ended and very faintly trifid above. The first lateral saddle is very broad and is rendered asymmetrically trifid by two sublobes, of which the one nearest the venter is small Invertebrate Fossils of the Navarro Group and nearly simple and the other is larger and bifid; the three subsaddles are each bifid. The first lateral lobe is smaller than the ventral lobe and is bifid. The second lateral saddle is bifid and is much smaller and simpler than the first lateral. The third lateral saddle is still smaller but is proportionately broad and is bifid. The third lateral lobe is quite small and simply trifid. The latter is followed by a small broad, simply bifid saddle, a small n~rrow lobe faintly bifid, a small, broad, simple saddle, a very small simple lobe, ~nd a simple saddle which straddles the lme of involution. Any of the simple lobes or saddles may be faintly bifid on other parts of the same shell or on different shells. The inner suture as seen on very small stages consists of an antisiphonal lobe, 2 dorsal saddles and 2 dorsal lobes, the series decreasing in size from the dorsum to the line of involution. The antisiphonal lobe is narrow, about six-tenths as deep as the corresponding siphonal lobe, and is very simply digitate. The dorsal saddles are narrow and simply bifid; the dorsal lobes are narrow and simpler than the anti­siphonal lobe; the outer dorsal lobe is much narrower than the saddle which straddles the line of involution. The holotype, though preserving most of the living chamber, is incomplete at the apertural end. The greatest diameter of the shell as preserved is 45 mm. The greatest measurable dorso-ventral di~m­eter is 23 mm., and the correspondmg transverse diameter is about 17 mm. As shown by the inner broken cross sections the dorso-ventral diameter of the first 2 or 3 volutions is a little shorter than the transverse diameter; the greater length of the former becomes easily noticeable in the fourth volution and increases rapidly toward the living chamber. The regular coiling of the main part of the shell, the compressed sides, the flattened venter, and the multiple rows of lateral nodes ally this species with the group for which Meek09 proposed the name Discoscaphites, naming Scaphites conradi Morton as the type species. Types.-Holotype, U.S.N.M. no. 77310; I figured paratype, U.S.N.M. no. 77311; "'Meek, F. B., Rept. U. S. Geol. Suney Terr., vol. 9, p. 415, 1876. 7 unfigured paratypes, U.S.N.M. no. 77312. Distribution in Texas.-Navarro group, Kemp clay: 31/z miles northwest of Bazette (12922, type loc.); branch 61h miles southwest of Currie (14139, 17377) ; 41;2 miles east-northeast of Cooledge (17374). Range.-Known only from 3 localities in the Kemp clay within 15 or 20 feet of its top. DISCOSCAPHITES ERUCOIDEUS Stephenson, n.sp. Pl. 91, figs. 2-4 Shell small, strongly involute, deeply embracing, compressed laterally through­out the exposed portion. Umbilicus very small and deep. Venter broadly rounded. The shell is probably in a median stage of the growth of the individual, and the living chamber is broken away. The form of the preserved portion suggests that the living chamber, if present, would not be greatly elongated. The conch is considerably expanded in the dorso-ventral direction. The surface is covered with numerous low rounded ribs which cross the venter with undiminished strength; on the one exposed volution these number 57 on the venter and only about 15 on the umbilical shoulder where they become somewhat obscure; the ribs increase in number from the umbilicus outward in part by forking and in part by intercala­tion. The ribs trend noticeably forward on the sides of the shell and cross the ventor with a scarcely perceptible forward curve. On the largest part of the shell 2 rows of nodes of 3 nodes each are present, one on each side of the rounded venter; the nodes occupy about every third rib. A row of very obscure nodes is present on each side above the midline between the umbilicus and the venter on the smaller exposed part of the shell up to a diameter of about 19 mm. There is a tendency for obscure nodes to form at the rib forks. The sutures, though not completely ex­posed, appear to be essentially like those of Discoscaphites nicolleti (Morton) and D. conradi (Morton) , though differing in detail. The ventral lobe is large, deep and provided with digitate prongs; the The University of Texas Publica.tion No. 4101 3 prongs on either side become progres· sively smaller from rear to front, and the posterior one is divided; the ventral saddle is proportionately broad and extends for­ward about one-third the length of the ventral lobe. At a diameter of about 15 mm., the first lateral saddle is large, moderately broad, and slightly asym· metrical; of the 3 terminal subsaddles the two nearest the venter are slightly di­vided and the third more strongly so; the latter is separated from the other two by a proportionately wider and deeper sublobe. The first lateral Jobe is large and terminates posteriorly in 4 widely separated, digitate prongs, all of which are divided; the second lateral saddle is pro­portionately small and bifid; the second Iatera1 lobe is small and appears to terminate in 4 sim pie digitate prongs. The greatest diameter of the shell is 23 mm.; the greatest measurable distance from the umbilicus to the venter is 15 mm.; the greatest dorso-ventral diameter, measured from the venter of the penulti­mate whorl, is 9 mm.; and the maximum width is 10.5 mm. The compressed sides and the presence of nodes, thougl) poorly developed, seem to place this shell in the genus Discoscaphites Meek. It is closely related to Di.scoscaphites nicolleti (Morton). Holotype.-U.S.N.M. no. 77313. Distribution in Te:ras.-Navarro group, Nacatoch sand: 2 l ·'10 miles northeast of Chatfield (Tex. Bu. 17302). Unidentified specimens of DISCOSCAPHITES Fragments of internal molds, probably representing either 5 or 6 species of Discoscaphites, have been collected from the Corsicana marl at six widely separated localities in Texas. Two of the specimens came from a public east-west road, 1 % miles south by east of Oak Grov~, Bowie County (16160). One of these specimens ( U .S.N .M. no. 77314), representing a portion of the shell back of the living chamber (pl. 91, fig. 6), is a strongly compressed form characterized by a narrow venter and by rows of small, closely spaced nodes. The venter bears three rows of nodes of which the central one is much weaker than the others. At least 2 lateral rows of nod• may be seen on each side closely paral.. lelfng the marginal ventral rows; if ad. ditional rows of nodes are present lower on the sides, they are not recognizable on account of corrosion. The maximum dorso-ventral diameter measures 17 + mm., and the corresponding transverse diameter 12.2 mm. The other specimen from this locality (U.S.N.M. no. 77315) is a short fragment back of the living chamber (pl. 90, figs. 5, 6) . The Rat· tened venter is very narrow and the 2 rows of ventral nodes are close together. Moderately strong and rather closely spaced ribs are present, and each side bears 4 rows of nodes between the ventral row and the row on the umbilical shoulder; in each row nodes are present on successive ribs. The dorso-ventral diameter measures 16.5 mm., and the corresponding tr an s v er s e diameter 17.7 mm. A mechanically compressed, small in· ternal mold, incompletely covered with a thin film of original shell substance, was found in a small branch below a public road 21;2 miles north of Tona siding, S miles southwest of Quinlan, in Hunt County (15546). This specimen (pl. 91, fig. 7) exhibits low rounded ribs which become stronger toward the venter. There are 2 rows of marginal ventral nodes; the nodes in the 2 rows form pairs which are joined by 2 small ribs formed by the bifurcation of the lateral ribs at the nodes. The species is closely coiled and the umbilicus is small. Although lateral rows of nodes can not be definitely differen· tiated, the general form and appearance of the shell suggest that it belongs to Discoscaphites. The shell is about 20 mm. in greatest diameter. U.S.N.M. no. 77316. The impression of a mechanically flat· tened Discoscaphites, apparently repre­senting most of the shell back of the living chamber, was obtained in the Corsicana marl on the Mexia road 2 4/5 miles east of Cooledge, Limestone County (13832}. Faint impressions of sutures may he seeD over all the specimen. The shell (pL 91, fig. 8) is closely coiled and expands rapidly. Moderately strong marginal ventral nodes are present; 2 or 3 rows of lateral nodes may be detected, but are weakly developed. The maximum diam­eter of the crushed shell as preserved is about 30 mm; the maximum dorso-ventral diameter measures about 21 mm., but this apparent dimension may be an exaggera­tion caused by mechanical deformation. U.S.N.M. no. 77317. A poorly preserved fragment of a por­tion of a living chamber, from the left bank of San Marcos River, 1;2 mile below Martindale, Caldwell County ( 7621) , rep­resents a medium-sized shell with mod­erately strong nodes including marginal ventral nodes, nodes on the umbilical shoulder, and at least 3 rows of nodes on each side. The ribs are rather ob­scurely developed. U.S.N.M. no. 77318. A fragment of a form with flattened sides, representing a part of the shell back of the living chamber (pl. 91, fig. 5), from a westward-facing bluff on Guada­lupe River, 1 3/10 miles north of Mc­Queeney, Guadalupe County ( 15524), ex­hibits 2 rows of ventral nodes, the pairs of which are linked by small double ribs formed by the bifurcation of the lateral ribs at the nodes. No lateral rows of nodes are recognizable. The maximum dorso-ventral diameter is 10 + mm. and the corresponding transverse diameter is 8.8 mm. This specimen may belong to the same species as the one described from Hunt County (15546), but the me­chanically compressed condition of the latter prevents certain identification. U.S.N.M. no. 77319. A small, badly crushed specimen from a depth of 1045 feet in Redus No. 1 well of the Witherspoon Oil Company, on the G. A. Harper Survey, Medina County (13844), is ornamented with numerous costae, and by at least 2 rows of obscure! y preserved node5 on each side near the venter. U.S.N.M. no. 77320. The Kemp clay has yielded one incom­plete, badly crushed specimen that is specifically unidentifiable, but appears to he a Discoscaphites; it came from Elm Creek at the crossing of the Corsicana road, 2% miles north-northwest of Angus, Navarro County (9550). The part of the shell back of the living chamber is not greatly elongated. Two or 3 rows of lateral nodes appear to be present. A portion of the living chamber just back of the aperture is preserved and shows an irregular development of ribs, finest near the aperture, and 3 prominent nodes appear on the umbilical shoulder. U.S.N.M. no. 77321. The Kemp clay has also yielded a very obscure Discoscaphites from concretions in a field a mile west of Odds, in Falls County (17373). U.S.N.M. no. 77322. Family PLACENTICERATIDAE Genus PLACENTICERAS Meek PLACENTICERAS MEEKI Bohm Pl. 91, fig. 1; pl. 92 1876. Placenticeras placenta (DeKay) . Meek (in part.),. Rept. U.S. Geol. Survey Terr., vol. 9, p. 466, text fig. 65. ?1885. Pl a c e n ti c e r a s placenta (DeKay) . Whiteaves (in part), Geol. and Nat. History Survey Canada, Contributions to Palaeontology, vol. 1, pt. 1, p. 53. ?1889. Place n tic er as placenta (Dekay). Whiteaves On part), Geol. and Nat. History Survey Canada, Contributions to Palaeontology, vol. 1, pt. 2, p. ] 83. 1898. Placenticeras meeki Bohm, Zeitschr.. Deutsch. Geol. Gesell., Band 50, p. 200 (footnote) . 1903. Placenticcras whitfieldi Hyatt, U.S. Geol. Survey Mon., vol. 44, p. 22, pl. 45, figs. 3-16; pl. 46; pl. 47, figs. 1-4. 1910. Placenticeras whitfieldi Hyatt. Grabau and Shimer, North American Index Fossils. p. 218, figs. 1493, 1494. 1926. Placenticeras meeki Bohm. Reesicle, U.S. Geol. Survey Prof. Paper 147-A, pp. 1-5, pl. 1, figs. 1-7, 13; pl. 2, figs. 1-5. ?1927. Placenticeras whitfieldi Hyatt. Bose, Univ. Texas Bull. 2748, p. 276, pl. 1.3, figs. 1-3. 1927. Placenticeras mecki Bohm. Reeside, U.S. Geol. Survey Prof. Paper 151, p. 29, pl. 22, figs. 5-7 ; pls. 23, 24 ; pl. 25, figs. 1, 2. ?1930. Placenticeras meeki Bohm. Williams, Canada Dept. Mines, Nat. Mus. Bull. 63, Geol. Ser. 51, p. 6. ?1931. Placenticeras meeki Bohm. Link and Childerhose, Bull. Amer. Assoc. Pet. Geol., vol. 15, no. 10, pp. 1238, 1241, text figs. 9, 11. Shell of adult very large, compressed, strongly involute, with greatest transverse diameter near the umbilical shoulder. Venter narrow for the genus, flat with sharp marginal angles in all earlier stages, becoming rounded m adults. The Unirersity of Tc.ras Publication No. 4101 rmbi lieus proportionatcly small, with steep sides which do not OYerhang. rmbilical shoulder rounded. Surface smooth at all st3ges obserYed. A cross section at a diameter of about 227 mm. i~ shown in text figure 13. The sutures are characterized by elongated intricately branching saddles and digitate lobes. The siphonal lobe is both deep and wide and may be a little off center. The Yentral sad.dle is fully one-third as high as the lobe is deep: at a medial stage of growth it is subdiYided aboYe into 5 subsaddles, of which the two pairs on either side rise higher than the broad, blunt central one; this saddle becomes more complicated in the later stages. The two main lower branches of the siphonal lobe are deep, trend obliquely away from the venter, and are intricately branching. The first three lateral lobes are narrow and deep, the third one being wider and deeper than the others. The fourth lateral lobe is much shorter and smaller than the third, and the succeeding lobes and saddles be­come successiYely smaller. At the stage where the dorso-ventral diameter is about ]00 nun., the lateral saddles number 10 and the interYening lobes 9, to the line of inYolution; with increase in size lobes and saddles are added from within, and on large individuals may reach a dozen or more of each to the line of inYolution. The inner sutures are not uncovered. The greatest :measurable diameter from Yenter to Yenter, of the largest specimen from Texas. found in a cut of the Dallas highway 3 7 10 miles west of Kaufman, is approximately 530 mm. The body chamber is wanting, so that with this chamber added the shell must haYe been one of the largest recorded examples of the genu5. The greatest measurable radial dimension is about 33-1. mm. At the stage where the diameter of the shell is -1-00 mm. the radial dimension is approxi­mately 2-11 mm., and the corresponding maximum width 105 mm. The best preserved shell from Texas I pl. 92 ,l from the same locality as the preceding one has most of the Ii,·ing cham­lwr broken away: the ~hell measures 171 mm. in greatest on=-r-all diameter, and x7/ 9. Il'\ I \ I \ I \ I ' I \ I \ I \ I \ I \ I \ I \ : I \ \ I \ I \ I ' \\ I \ I \ ,I \\ I \ I \ I \ I \ I \ : I I \ \ I \ \ I I I \ I I I I I ' I I I I I I I I \ \ \ ' ' ' Invertebrate Fossils of the Navarro Group bean sutures to within 40 to 100 mm. of the broken edge of the living chamber. At the same diameter the height of the whorl from the umbilical center to the venter is 294 mm.; the height from the line of involution to the venter is 270 mm., and the maximum width is 145 mm.; the diameter of the umbilicus at the greatest over-all diameter, measured at the umbili­ cal suture, is 45 mm. The shells ref erred to this species are characterized by their large size, compressed sides, narrow venter, and narrow, greatly elongated sad­ dles and lobes. The measurements given abO'Ve can only he approximately correct owing to the imperfections of the speci­ mens and the mechanical deformations to which they have been subjected. It is estimated that if the living chamber (half a volution) were added to the largest shell measured, and if the shell maintained the same rate of increase in size, the maximum diameter would he not less than 780 mm. ( -approximately 2 ft. 7 in.). Type1.-Holotype, U .S.N .M. no. 3680. From North Red River, Minnesota. Two plesiotypes from Texas, U.S.N.M. nos. 77323, 77324. Diatribution in Texas.-Navarro group, Neylandville marl: lh mile north of Cooper (7509, 14062) ; ? 5 miles south­west of Caddo Mills (14091); ?2% miles northeast of Royce City (13834); 3 7 /10 miles west of Kaufman (14101, 1 speci­men figured; 17119, 1 figured specimen); ?2 7/10 miles northwest of Cooledge (16169). Ouuide dutribution.-Western Interior: Pierre shale and formations of equivalent age. Canada: The species has been re­ported from the Bear paw shale (Pierre age) at numerous localities in western Canada. Range.-Known in Texas only from the Neylandville marl of the Navarro group. Reported as ranging throughout the Pierre aliale and formations of Pierre age in the W11tern Interior and western Canada. PLACENTICERAS INTERCALARE Meek (variety) Pl. 94, figs. 3, 4 Shell small, stout for the genus, strongly involute, with flattened flanks diverging inwardly. Umbilicus small and deep with steep slopes. Umbilical shoulder rather broadly rounded. Venter at early stage narrow and flat or slightly concave; in later stages the venter is flat and widens more rapidly than on the holotype of the species which, though much larger, possesses a narrower venter at its largest stage; width of venter at largest s tage on this specimen about 5 mm. A row of coarse, strong nodes is present on the umbilical shoulder, and a second row not quite so coarse on the flank about two-thirds the distance from the first row to the venter. The venter hears two marginal rows of nodes which are rather small and closely spaced, but which are stouter and much less elongated in the direction of the venter than the corresponding nodes on the holotype. The suture is essentially like that of P. inter­calare. The siphonal lobe is broad with a broad, low ventral saddle and widely diverging lower branches. The first lateral saddle is moderately broad above, becoming very slender and irregular be­low. The succeeding lobes and saddles to the third lateral lobe are proportion­ately narrow and increase slightly in size away from the venter. The remainder of the external saddles and lobes are small and decrease in size toward the line of involution. At the maximum dorso­ventral diameter there are five interior saddles with four intervening lobes. The maximum dorso-ventral diameter on the figured specimen is 38 mm. and the corresponding width measured on the tips of prominent nodes is about 30 mm. (estimated) ; measured between the nodes the width would he about 24 mm. The description is based on one small septate specimen found embedded in a hard black phosphate nodule at the base of the Neylandville marl. The specimen may or may not have been reworked from the underlying Taylor marl. All the The University of Te:i:as Publication No. 4101 nodes are stouter than those of the typical P. intercala.re, the venter is noticeably wider and the ventral nodes are smaller and more closely spaced. 'When more maturf' specimens are discovered it may be found desirable to give this form a separate varietal, or perhaps a separate sprcific, name. Types.-Holotype, U.S.N.M. no. 369; from the upper part of the Pierre shale nt the junction of Sage Creek with Cheyenne River in the southwestern part of South Dakota. Plesiotype? from Texas, U.S.N.M. no. 77325. Dist.ribution in Texas.-Navarro group, base of Neylandville marl: 5 miles west of Kaufman (14102). Outside distribution.-Western Interior, Pierre shale (upper part). Range.-This variety is known only from the one locality cited in Texas. Meek's species is common in the upper part of the Pierre shale in the Western Interior. Family ENGONOCERATID.AE Genus SPHENODISCUS Meek The original description of Spheno­discus500 is as follows: In the same way, Ammonites lobatus of Tuom!'y may be regarded as the type of another group. differing from Placenticeras in having the periphery sharply cuneate all around, and the sinuses or saddles between its numerous lateral lobes (which agree in number and proportional size with those in Placenticeras, presenting Yery curious obtusely-lobed or uniform outlines. For this type I would propose the name Sphcnodiscus, in allusion to its sharply-cuneate periphery. In 1876, Meek501 gave a fuller descrip­tion of Splzenodiscus, treating it as a sub­genus of Placenticeras. In this paper Ammonites lvbatus Tuomey is placed in the s y n o n y m y under Placenticeras ( S plzenodiscus) lenticulare (Owen), but 500.\ledc, F. B.. Preliminary Report of :he United States Geological Survey cf Wyoming and portions of contiguoua terr:tories (being a Eecond annual report of progrese), pt. -1, p. ~98 (footnote), 1871. [Actually this is a fourth annual report; another identii::al edition bears the date 1872.] 601 .\fl'C'k, F. B.. Rept. U. S. Geol. Sun·ey Terr., '·ol. 9, p. 463, 476, 1876. Hyau,:>o:? in 1903, regarded the two species as distinct. Tuomey's description of Ammoni.les lobatus i~ as follows: ~hell discoid, smooth, thin towards the cir· rnmference; dorsal [ventral] lobe finely senate; lateral lobes [saddles] terminating in large bilobed cells. This fossil, of which I have only a fragmen~ resembles A. placenta, but is distinguished from it by the remarkable cel1s that terminate the lateral lobes [saddles]. Locality, Noxuhie County, Mississippi. Tuomey's description is inadequate and he did not figure the type, which is be­lieved to be lost. Hyatt figured two specimens under Tuomey's name, one large one (U.S.N.M. no. 2403) from Pontotoc County, Missis. sippi, and one small abnormal one (U.S. N.M. no. 20577) from Landers Mill (Rip· ley formation) in Tippah County, Mississippi. It may never be possible to prove that either one of these two speci· mens belongs to Tuomey's species, but if the name is to be accepted as valid if will be necessary to select one of them as neotype; since Meek states that he saw the large specimen from Pontotoc County, it would seem appropriate to choose that one. This procedure would necessitate a loose construction of the rule governing the selection of neotypes, namely, that the new type should come from the same lo· cality and horizon as the lost type. Since, however, the upper beds of the Upper Cretaceous are exposed in both Noxubee and Pontotoc counties, there is a reason· able possibility that the Pontotoc specimen does belong to Tuomey's species. In view of the general acceptance of the name, and the designation of the species as the geno­type of Sphenodiscus, less confusion would result from fixing the name on this selected neotype than would follow the attempted invalidation of the name. The whole subject of the proper basis for subdividing the genus Sphenodis~ into species and varieties needs reco~s1d· eration, with more material for comparison than is now available. Suture patterns alone do not seem to be dependable char· acters on which to base a subdivision of 602Hyatt, Alpheus, U. S. Geol. Survey Mon., •ol. 44. n. M lOO!t Invertebrate Fossils the genus and it would seem necessary therefore to look for consistent differences in form and ornamentation in large suites of specimens. SPHENODISCUS TIRENSIS Stephenson. n.sp. PI. 93, figs. 1-3; pl. 94, figs. 1, 2 Adult shell large, smooth, lenticular in cross section, strongly involute, umbilicus small, flanks slightly flattened on the inner half; outer half presenting a series of faint, widely spaced, broad, low radial swells. Umbilicus small and deep, with broadly rounded shoulder. Venter sharp­edged in young stages, with angle 60 de­grees or less, becoming wider and acutely rounded in adults. Septa not unduly crowded. Sutures variable on the same and on different individuals. At a radial dimension of 125 mm. the lobes and saddles number 15 each between the venter and the line of involu­tion. Ventral lobe very broad and of only moderate depth, with the two lower branches diverging strongly; ventral saddle very broad and low, with serrate upper margin, finest in center, ending at each outer corner in a small rounded sub­saddle. The first four lateral saddles are in general narrow and only moderately high, but become progressively higher in the larger stages; they are bilobate with the lobate parts either simple or partly subdivided by one or more shallow inden­tations; the fifth and sixth saddles may be either simple or bilobate and the rest of the saddles to the line of involution are generally simple and broadly lobate, though saddles may be divided as far as the ninth. The lateral lobes increase in size to the third which is quite large; the fourth lobe is much smaller than the third, and the succeeding lobes become progres­sively smaller and simpler to the line of involution. The large lateral lobes are divided into 3 or 4 thick-stemmed branches, each of which ends in 4 or more dull­pointed digitations. A group of internal saddles and lobes at a young stage is shown in plate 94, figure 2. A maximum of 10 simple saddles and 9 lobes appears in the longest suture. The individual variation in the sutures and the unsymmetrical development of the sutures on the two sides of given individ­uals are striking features of this species. of the Navarro Group 435 It is not uncommon for 4 or 5 of the larger saddles on one side to be divided and 6 on the other. On one specimen from the Chapman farm the first lateral saddle is much broader and lower than is typical; on one side of this specimen the first four lateral saddles are divided, the fifth and sixth are simple, the seventh is divided, the eighth simple, and the ninth divided; on the other side of the same specimen the first six saddles are divided, the seventh is simple, and the eighth and ninth slightly divided. The largest radial dimension of the holotype is about 125 mm., and the cor­responding width is 49 +mm. (this speci­men is slightly crushed laterally). The largest specimen in the collection from the Kemp clay has a radial dimension of 165 mm. S phenodiscus lenticular is (Owen) , no 3 from the Fox Hills sandstone of the Western Interior is based on a very im­mature shell which, as figured, does not show the sutures, and is inadequate for specific description. The shell (U.S.N.M. no. 411) described and figured by Meek501 under that name appears to be more thinly lenticular in cross section than the species under consideration, and the septa are more closely crowded throughout; the specimen is a young stage, the maximum radial dimension of which is 60 mm. The specimen from the Monmouth formation of Maryland described by Gardner under the name Sphenodiscus lobatus (Tuomey) is a young shell the sutures of which are similar to those of the shells commonly referred to S. lenticularis. The same may be said of the young speci­men from the Peedee formation of South Carolina described under the name Sphenodiscus lobatus var. a.llisonensis Stephenson.505 Types.-Holotype, U.S.N.M. no. 77326; 1 figured paratype, U.S.N.M. no. 77327; 2 unfigured paratypes, U.S.N.M. no. 77328; 1 figured example, U.S.N.M. no. 77329. 0030wcn, D. D., Rept. U. S. Geo). Survey Iowa, Wisconsin, and Minnesota, p. 579, tab. 8, fig. 5, 1852. 604Meck, F. B., Rcpt. U. S. Geo]. Survey Terr., vol. 9, p. 473, pl. 34, figs. la-c, 1876. 5()6Stephenson, L. W., i'i'orth Carolina Geo!. and Econ. Survey, vol. 5, p. 397, pl. 99, figs. l, 2, 1923. The University of Texas Publication No. 4101 Distribution in Texas.-Navarro p;roup, Corsicana marl: ?11/i miles south by east of Oak Grove (16160); l 9 '10 miles northea~l of Quinlan (1692 l) : '? l 4/5 miles N. 20° W. of Tona siding (155.JS) ; ?fuller's earth pit 14 miles west of San Antonio (1562·1) : well on G. A. Harper Survey. Medina County (l 38U, at depth of l 015 feet). Navarro group, Kemp clay: P~ miles sm1theast of Tira (12930. type loc.) ; 2 miles south of Tira (12865) ; 3 miles ~·outheast of Corsicana (17367) : branch 6% miles southwest of Currie (l-H39, 1 figured example) ; 1 mile east of Kimbro store (Tex. Bu. 903) ; ?3 miles southeast of Manor (16141); near Webberville (I 642) ; ?4~--~ miles northwest of Lock­hart (16151); south of McQueeney (7638, ]5525). Range.-Corsicana marl and Kemp clay. SPHENODISCUS PLEURISEPTA (Conrad) Pl. 95, figs. 1-4 1857. Ammonites pleuriscpta Conrad, 0.S. and Mex. Bound. Survey, vol. 1, pt. 2, p. 159, pl. 15, figs. la-c. 1861. Ammonites pedemalis Binckhorst (in part), :Mon. Gast. et Ceph. Craie Super. du Limbourg; Class Cephalopodes, p. 21. pl. Sal, fig. la, b (only). ?1898. Sr:henodiscus pleurisepta (Conrad). Bohm. Zeitschr. Deutsch. geol. Gesell., ,·ol. 50, pp. 193-197, pl. 7, figs. 1, la, lh. 1903. Sph<'nodiscus pleurisepta (Conrad). Hyatt, 11.s. Geol. Survey 1\fon., vol. 44, p. 59, pl. 3, figs. 7-15; pl. 4; pl. 5, figs. 1-3; pl. 6, fig. 6. ?190--t. Sphenodiscus pleurisepta (Conrad). Lasswitz. Geol. and Paleont. Abhandl.. n.~.. Bd. 6. Heft 4, p. 11 (231), pl. 2 (14) ' fig. 3. 192-l. Spl:enodisrus pleurisepta (Conrad). Deus­"l n. l 1.S. Geol. Survey Prof. Paper 126, pl. 12 (opp. p. 36), figs. 3, 3a. (Figures only.) 1927. Sphcnodisrns pleurisepta (Conrad). Bose, l 'ni,-. Texn~ Bull. 27-1-8, p. 304, pl. 17, fif!!'. 2 s. Adult shell medium to large, thinly len­ticular in cross section, stronaly involute. L mbil icus wry small and e deep with broadh· rounded shoulder roundinrr . ' b steeply down within and overhanging in lower part of each volution. Greatest width of conch about midway of the flank; inner half of flank flat to slightly concave, sloping gently to the umbilical shoulder; outer half rounding broadly to the venter. V Pnter sharply acute in the younger stages, with angle of 60 to 70 degrees, becoming sharp1y rounded in middle and older stage~. Th(> surfacc> is smooth with the excq>tion of two rows of nodes on the flanb: on the holotype one row midway of the flank consists of 11 exposed, dis· tinct. but not prominent, nodes somewhat irregularly spaced 7 to 15 mm. apart; the other row lies a little more than mid. way between the first row and the venter, and consists of more widely spaced, non· prominent nodes which in the earlier stages are round, but in later stages become radially elongated and in adults become broad, widely spaced undulations; 14 of these nodes and undulations are exposed on the holotype. Septa rather evenly dis· tributed and not closely crowded on the holotype, which has a maximum diameter of 93 mm. Ventral lobe broad and shal· low with short, widely diverµ:ent, quadri· partile lower branches; ventral saddle very low and broad with a serrate upper margin. On the holotype the lateral saddles number I4 to the line of involution. At a radial dimension of 53.5 mm. the first lateral saddle is broadly lobate and undivided above, becoming slightly divided on the sides below; the next 3 lateral saddles on one side are bilobate, and the remain· ing l 0 to the line of involution are single; on the other side the next 3 lateral saddles after the first simple one are bilobate, the fourth is slightly divided, and the 9 re· rnaining ones are single. The lateral lobes are moderately broad and are bluntly digitale, thf'y increase in size to the third, the fourth is much smaller than the third, and the remainder decrease progressively in size and complexity to the line of in· Yolution. The inner sutures are not fully exposed on the available material, although it can be seen from plate 95, figure 1, that there are at least 9 saddles and 9 lobes on the largest stage of that specimen. -When the different specimens, which have been referred to this species, mainly on the basis of form and sculpture, are compared, their suture patterns at the same stage are found to cliff er considerably on different individuals in width, height, and complexity of division; for example, on some the first lateral saddle is simply lobate, and on the others bilobate, or even Invertebrate Fossils of the Navarro Group quadrilohate; similar differences are pre­sented by the other larger saddles. It is apparent, therefore, that suture patterns can not he depended upon as criteria for the differentiation of species. Dimensions of the holotype: Greatest diameter of shell 93 mm.; greatest radial diameter 53.5 mm.; greatest width 20.4 mm.; maximum umbilical diameter 6 mm.; the largest shell in the collections now under consideration has a diameter of 115 mm., hut specimens in the Escondido formation not yet critically studied, which appear to belong to this species, attain diameters of 230 mm. or more. Types.-Holotype, U.S.N.M. no. 9888; this specimen is recorded as having come from "Jacun, 3 miles below Laredo," Webb County; this is obviously an error because beds of Cretaceous age do not crop out within the borders of this county. The specimen is believed to have actually come from the Escondido formation in Maverick County, which adjoins Webb County on the northwest. Plesiotypes from Texas, U.S.N.M. nos. 77330, 77331. Distribution in Texas.-Navarro group, Corsicana marl: About 5 miles east by north of Greenville (12924) ; ?2 miles south of Cliff (16719). Navarro group, Kemp clay: l lh miles southeast of Tira (12930, 2 figured speci­mens) ; 31h miles northwest of Bazette (12922, 1 figured specimen) ; branch 61/2 miles southwest of Currie (14139); we::;t of Zuehl (7720) . Navarro group, Escondido formation: The species is common in this formation. Outside distribution.-Mississippi, Owl Creek formation. Mexico: Escondido formation. Range.-Upper part of Navarro group of Texas in Corsicana marl, Kemp clay and Escondido formation; OwI Creek formation of Mississippi. Unidentified specimens of SPHENODISCUS Specimens of Sphenodiscus too poorly preserved for specific identification have been collected as indicated below. One lot from the N acatoch sand near Kaufman, Kaufman County (761, U.S. N.M. no. 20975), consists of two speci­mens, one a badly corroded, thinly lenti­cular shell about 252 mm. in greatest diameter, and the other the living cham­ber of a smooth lenticular shell having a maximum diameter of about 133 mm. Another very small fragmentary specimen was found along the Dallas highway 3/5 mile west of Kaufman (14098, U.S.N.M. no. 77332). Although poorly and incom­pletely preserved these specimens demon­strate the presence of S phenodiscus in the N acatoch sand. A fragment of a venter of a S pheno­discus was obtained from the Corsicana marl in the pit of the Corsicana Brick Company, 2 miles south of Corsicana, Navarro County (16167). U.S.N.M. no. 77333. A fragment of a young individual from the Corsicana marl in a public road 4 miles southwest of Quinlan, Hunt County ( 17385) , has an unusually short and broad first lateral saddle. U.S.N.M. no. 77334. The Kemp clay has yielded compressed fragments of a specimen of S phenodiscus of medium size from a concretion in a field a mile west of Odds, in Falls County ( 17373), which has sutures possibly re­lating it to S. tirensis. U.S.N.M. no. 77335. Subclass DIBRANCHIATA Order BELEMNOIDEA Family BELEMNITIDAE Genus BELEMNITELLA D'Orbigny BELEMNITELLA AMERICANA (Morton) Pl. 95, figs. 5-8 1828. Belemnites subconicus Lamarck. Morton, Acad. Nat. Sci. Philadelphia Jour., lst ser., vol. 6, p. 91, pl. 5, fig. 7. 1830. Belemnites americanus Morton, Am. Jour. Sci., vol. 17, p. 281; vol. 18, pl. I, figs. 1-3. 1830. Belemnites americanus Morton, Acad. Nat. Sci. Philadelphia Jour., 1st ser., vol. 6, p. 190, pl. 8, figs. 1-3. 1834. Belemnites americanus Morton, Synopsis of the organic remains of the Cretaceous group of the United States, p. 34, pl. l, figs. l-3a; pl. 17, fig. 2?. 1850. Belemnitella mucronata D'Orbigny (in part), Prodrome de Paleontologie, vol. 2, p. 211. (Not B. mucronata Schlot­heim.) 1858. Belemnitella americana (Morton). Em­mon~ North Carolina Geol. Survey Rept., Agriculture of the eastern coun­ties, Raleigh, p. 246, text fig. 102. 1861. Belemnitella mucronata (Morton). Gabb, Synopsis of the Mollusca of the Creta­ceous formations, p. 22. (Also Am. Philos. Soc. Proc., vol. 8, p. 78, 1861.) The Uniz:ersity of Texas Publication No. 4101 186-1.. Bt'lcmnitella paxillosa (Lamarck). Meek. Check list of the invertebrate fossils of North America. Cretaceous and Jurassic: Smithsonian l\lisc. Coll., vol. 7, no. 177, p. 26. 1868. Bdemnitdla mucronata D'Orbigny. Con· rad. Geol. Suney New Jersey (Geology of New Jersey, by G. H. Co~k), p. 375, text fig. 1892. Belcmnitt:lla americana Olorton). Whit­field, C.S. Geol. Survey l\lon., vol. 18, p. 280, pl. 47, figs. 1-11. (Geol. Sur­vey New Jersey, Paleontology, ml. 2, p. 280, pl. 47, figs. 1-11, 1892). 1905. Belt!mnitella americana (l\lorton). John­son, .Acad. Nat. Sci. Philadelphia Proc., rnl. 57, p. 28. 1907. Belemnitdla americana (Morton). Weller, Geol. Suney New Jersey, Paleontology, vol. 4, p. 839, pl. 109, figs. 1-4. 1911. Bt>lemni.ulla americana (Morton). l\Iiller, Maryland Geol. Survey, Prince Georges County, p. 96, pl. 5, fig. 2. (Figure only.) l 916. Belemnitclla amcricana (l\lorton). Gard­ner, l\laryland Geol. Survey, Upper Cre­taceous (2 vok), p. 394, pl. 12, figs. 4 -6. 1923. Bt>lemnitella am er i can a (.Morton). Stephenson, North Carolina Geo!. and Econ. Suney, rnl. 5, p. 398, pl. 99, figs. 3-7; pl. 100, figs. 1-3. 1926. Belcmnitella a 1n er i can a (~lorton). Stephenson, Geol. Survey of Alabama Special Rept. No. 14, p. 2-t.s, pl. 91, fig. 12. (Figure only.) 1929. Belemnitella americana (:Morton). Dane, Arkansas Geol. Survey Bull. 1, p. 136, pl. 2-1, figs. 5, 6. (Figures only.) This species is represented in the col­lections by guards from only five Navarro locaties in central and northeastern Texas, and the specimens are more or less fragmentary and incomplete. The two lots from the Corsicana marl were collected bv Mr. and Mrs. D. A. Saunders, who d~nated them to the United States Geo­logical Survey. The available material indicates elongated, tapering guards typical of the species. The inner end of the slender conical cavity occupied by the alveolus is preserved on several of the specimens, and the lower tip of the ventral furrow may be seen on two of them. The dorso-lateral grooves and the vascular im­pressions are preserved on several speci­mens. The largest fragment has a maxi­mum diameter of 12.5 mm. Compared with Belemnitella mucronata (Schlotheim) from the Senonian (upper Campanian and Maestrichtian of Europe the American species is more slender and tapers less abruptly to the papillary tip. Types.-Morton's types, including the one large typical guard, and the two smaller so-called varieties A and B, which appear to be only individual variants, are preserved in the collection of the Academy of Natural Sciences of Phila· delphia;· they are recorded as having come "From the calcareous strata of New Jersev especially on Timber Creek, Glouceste~ County." Three plesiotypes from Texas, U.S.N.M. no. 77336. Distribution in Texas.-Navarro group, Nacatoch sand: About 2 miles northeast of Quinlan (16930) ; ?north edge of Corsicana (518). Navarro group, Corsicana marl: 1 4/5 miles northeast of Quinlan (11248, plesio· types) ; Salado Creek, below St. Hedwig road, Bexar County (16670). l\avarro group, Kemp clay: 12 miles southeast of Greenville (11247). Outside distribution.-Arkansas: Sara­toga chalk and Nacatoch sand. Mississippi: Ripley formation, upper part of Selma chalk (including Exogyra cancellata zone), and Prairie Bluff chalk. Alabama (central and west-central part) : Prairie Bluff chalk. Chattahoochee region (Alabama): Up· per part of Ripley formation. North Carolina: Peedee formation. Maryland: Monmouth formation. Delaware: Mount Laurel sand. New Jersey: Mount Laurel sand and Navesink marl. Range.-In Texas the species has been recorded from the Nacatoch sand, the Corsicana marl, and the Kemp clay. In the Atlantic and Gulf Coastal Plain in general the range is through the Exogyra costata zone. The University of Texas Publication No. 4101 PLATE 3 PAGE Cliona microtuberum, n.sp.____ ---------__ ---_______ --____ ----------------------------------------------------------------------------------------54 1. Holotype (U.S.G.S. coll. 11250; U.S.N.M. No. 76266). Phosphatic casts of borings in shell of Exogyra costata, from the Corsicana marl, east side of Cedar Creek, 7 miles south, 3 miles east of Greenville, Hunt County. 2. Enlarged view (x6) of a selected portion of the holotype. 3. A paratype (U.S.G.S. coll. 13568; U.S.N.M. no. 76268). Phosphatic casts (x3) in shell of Exogyra costata, from the Corsicana marl, east-west public road, 1% miles south by east of Oak Grove, Bowie County; shows turnip-shaped easts aligned in rows. 4, 5. Views of casts of this species, which preserve the form of Crassatella vadosa Morton, in whoet shell the organism bored (U.S.G.S. coll. 6793; U.S.N.M. no. 76270) ; from the Prairie Bluff chalk, Prairie Bluff, Alabama River, Wilcox County, Alabama. CLiona, sp. __________________________________________________________ · ----------------------------------______________________________________ ---------------55 6. Casts of borings (x3) in a shell fragment from the Kemp clay, Webberville, Travis County (U.S.G.S. coll. 7601; U.S.N.M. no. 76269). Lingula aff. L. subspatulata Hall and Meek________________________________________,_______________________________________________ 70 7-9. Three valves (x4) from the Kemp clay, 3% miles northwest of Bazette, Navarro County. (U.S.G.S. coll. 12922; U.S.N.M. no. 76286.) Terebratulina noackensis, n.sp..________________ __ ____ _--------------------------------_________________________ -------------------------· 70 10-12. Holotype (U.S.G.S. coll. 17370; U.S.N.M. no. 76287). Dorsal, ventral, and edge views; from the Lase of the Kemp clay in branch of Mustang Creek, 3 miles south, 30 degrees west of Thrall, Williamson County. The Unlver•lty of Texas Publlcatlon 4101 Plate 3 The University of Texas Publication No. 4101 PLATE 4 PAGI Serpula cretacea (Conrad) --------------------.-------------------------------------------------------------------------------------------56 1, 2. Views of a colony of tubes from the Nacatoch sand near Kaufman, Kaufman County. (U.S.G.S. coll. 761; U.S.N.M. no. 21001.) 3. Operculum (xlO) in a tube in the same collection. (U.S.N.M. no. 76294.) Serpula? lineata (Weller) -------------------------------------------------------------------------------------------------------------------57 4-6. Fragments of tubes (x 1%) from the Nacatoch sand on Postoak Creek at north edge of Corsicana, Navarro County. (U.S.G.S. coll. 518; U.S.N.M. no. 20891.) Serpula bowiensis, n.sp. --·--·----_ __ ____ _ _ ___ __ __ -----------------------------------------------------------------------------------58 7. Holotype (U.S.G.S. coll. 16160; U.S.N.M. no. 76271). Tube (xl%) attached to a shell fragment from the Corsicana marl in public road, 114 miles south by east of Oak Grove, Bowie County. IIamulus onyx Morton ------------------------------------------·------------------------------------------------------------------------------------58 8. Tube (x2) from the Corsicana marl near oil-test well of Morgan Oil Company, 2 3/5 miles north Ly east of Malta, Bowie County. (U.S.G.S. coll. 16159; U.S.N.M. no. 76273.) 9. Operculum (x6) in tube from the Nacatoch sand in field, 3/5 mile west of Kauf­man, Kaufman County. (U.S.G.S. coll. 14103; U.S.N.M. no. 76272.) Hamulus squamosus Gabb ____ .__________________ __ ___________ ----------------------------------------------------------------------------------60 IO. Tube (x2) from the Corsicana marl near oil-test well of Morgan Oil Company, 2 3/5 miles north by east of Malta, Bowie County. (U.S.G.S. coll. 16159; U.S.N.M. no. 76274.) Hamulus? huntensis, n.sp. ------------------___ _ -·----___ -----------------------------------------------------------------------------------61 11--14. Views of cotypes (U.S.G.S. coll. 12925; U.S.N.M. no. 76275) from the Nacatoch sand on the Guthrie place, 11/2 miles west of Campbell, Hunt County. 15. Cross section (x3) of one of the cotypes. 16. Longitudinal section (x2) of one of the cotypes. The University of Texas Publication 4101 Plate 4 The University of Texas Publication No. 4101 PLATE 5 PAGE Cliona microtuberum, n.sp. -------------------------·----------------------------------------·-------------------------------------------------54 1. Enlarged view (x3) of selected part of the holotype (U.S.G.S. coll. 11250; U.S.N.M. no. 76266.) 2. Casts of this species (x2), which preserve the form of a shell of Turritella sp., in which the organism bored (U.S.G.S. coll. 11247; U.S.N.M. no. 76267); from the Kemp clay (reworked in base of Kincaid formation), 12 miles southeast of Green· ville, Hunt County. Spine of cidarid echinoid __ __ ___ __ __ __ _ _-----··---_ -------------··-----------------------------------------------------------------------62 3. Spine (x2~) of a cidarid from the Nacatoch sand near Lewis Ferry on Red River, 8 miles north of New Boston, Bowie County. (U.S.G.S. coll. 12935; U.S.N.M. no. 76278.) Cardiaster leonensis, n.sp. ----------------------------______ -------------------------·--------------------------------------------------------62 4-6. Views (x3) of the holotype (U.S.G.S. coll. 15522; U.S.N.M. no. 76279), from the Corsicana marl in an abandoned earth tank, north of Castroville road, 1 1/5 miles west of Leon Creek, Bexar County; note associated spines on base in figure 6. 7. Apical system and adjacent ambulacral and inter-ambulacral plates (x41h) ; pre· pared from figure 6 on plate 6, which is a photograph of the holotype taken under water. The University of Texas Publlcatlon 4101 Plate 5 The University of Texas Publication No. 4101 PLATE 6 PACE H emiaster dalli Clark ___________ ---------------------____ ------------------------------------------------------------------------------------------63 1-4. Views ( x2) of a specimen from the Corsicana marl on the San Antonio road, 6 miles east of Castroville, in Bexar County. (U.S.G.S. coll. 15502; U.S.N.M. no. 76280.) Cardiaster leonensis, n.sp. ----------------------------------------------------------------------------------------------------------------·-----62 5. Top view (x3) of the holotype rnal. molJ. with some shell matter adhering, of a paratype (U.S.G.S. coll. 161: LS.N.\I. no. 76518 I from the Nacatoch sand near Kaufman, Kaufman Countv. 23. Dorsal ,~iew (x:2) of a specimen from the same locality. Liopistha fvrmvsa. n.sp. ___ --·-----------______ -----·--· ---------------------------------·----------------------------------------------------­ 2.i. Holotype (x11 ~), a right rnhe (U.S.G.S. coll. 763: U.S.N.M. no. 20897), from the :\acatoch sand near Corsicana, Navarro County. 25, 26. Yiews f xl % ) of a paratype (ll.S.G.S. coll. 762: U.S.N.M. no. 21062) from the l\acatoch sand near Chatfield, Navarro County. Liopistha prott'xta (Conrad) _____.. _.. ___ ___ ______------------------------------------------------------·------------------------­ 27. Left rnh-e of a spe('imen from the Nacatoch sand on Postoak Creek at north edge of Corsicana. ~arnrro County. (U.S.G.S. coll. 518; U.S.N.M. no. 76513.) 28. 29. Enlarged views (x2) of the same :::1pecimen. 30. Right rnh-e (x2 l from the Owl Creek formation on Owl Creek, Tippah County, :\lississippi. ~ l'.S.G.S. l'oll. 707; U.S.N.M. no. 76514.) Cuspidaria grandis~ n.sp. ___ __ ____ _____ _________ ------------------------------------------------------------------------------------------­ 31. Holotype, a left rnh-e (LS.G.S. coll. 7637; U.S.N.M. no. 76519), from the Corsi­cana marl in a bluff on Gua of the Cor~icana marl, 4 miles southwest of Corsicana, Navarro County. Cusp1 dar1a sp. __ _ __ ____ _ ___________ ._.____ .___ ..__________-----------------------------------------------------------------------------------------­ 33. .-\ left rnhe (x2~ Gl from the Nacatoch sand on public road 21h miles north of Corsicana. NaYarro County. (U.S.G.S. coll. 14114; U.S.N.M. no. 76521.) ('uspidaria? sp. ______ ________ ___ _ ___ ____________ __ ____ ______-----------------------------------------------------------------------------------------­3+. .-\ ri~ht Yahe from the ~aeatoch sand on the Stevens place, 1 4/5 miles northeast . . . of Quinlan, Hunt County. ( U.S.G.S. coll. 16162; U.S.N.M. no. 76522.) (,US pu/(J Tl ll ~Jl. __ .._. __ ---· -----------------..._-----___________________----- ------------------------------------------------------------------------------­ 35. .-\ right rnh·e (x6 l from the Corsicana marl on the Mexia road 2 4/5 miles east of Cooledge, Limestone County. (U.S.G.S. coll. 14137; U.S.N.M. no. 76523.) PACE 181 181 175 174 183 172 172 170 165 164 162 166 167 167 167 168 The University of Texas Publlcatlon 4101 Plate 26 The University of Texas Publication No. 4101 PLATE 27 PAGE Astartemya Jeritressensis, n.sp. ---------------------------------------------------------------------------------------------------173 I. Squeeze from external mold of the holotype, a right valve (U.S.G.S. coll. 16149; U.S.N.M. no. 76536), from the Kemp clay in field, 3 1/5 miles northwest of Fentres.g, Caldwell County. 2. Squeeze from internal mold of the holotype. 3. Squeeze from internal mold of a paratype, a left valve (U.S.G.S. coll. 16151; U.S.N.M. no. 76537), from the Kemp clay in public road, 4% miles north· west of Lockhart, Caldwell County. Astarte sulcata De Costa -------------------------------------------------------------------------------------------------------------------------173 4, 5. Interior views of a typical Astarte inhabiting the waters of Loch Gare, Scotland; inserted for comparison with the hinge of Astartemya fentressensis. J'eniella conradi (Morton) ________ _ ____ _______ _____ ----------------------------------------------------------------------------------------· 168 6. A specimen from the Kemp clay near a public road, 2 miles north-n011hwest of Deatsville, Travis County. (U.S.G.S. coll. 14128; U.S.N.M. no. 76525.) 7. A right valve from the Nacatoch sand in public road, 21h miles north of Corsicana, Navarro County. (U.S.G.S. coll. 14114; U.S.N.M. no. 76526.) 8. A large left valve from the Kemp clay in field, 314 miles east by north of Manor, Travis County. (U.S.G.S. coll. 13861; U.S.N.M. no. 76524.) Crassatella quinlanensis, n.sp. ---------------------------------------------------------------------------------------------------------------179 9. Holotype, a right valve (U.S.G.S. coll. 16162; U.S.N.M. no. 76553), from the Nacatoch sand on the Stevens place, 1 4/5 miles northeast of Quinlan. Hunt County. 10. A smaller left valve, a paratype (U.S.N.M. no. 76554), from the same locality. 11. Enlarged view (xl%) of a young left valve, a paratype, from the same locality, showing the uncorroded sculpture near the beak. Crassatella vadosa cedarensis, n.var. --------------------------------------------------------------------------------· 178 12. Holotype, a left valve (U.S.G.S. coll. 16170; U.S.N.M. no. 76551), from the Ney· landville marl in the Corsicana road, 2% miles north of Corbet, Navarro County. The University of Texas Publication No. 4101 PLATE 28 Slab of roquina-like calcareous sandstone (reduced as indicated by scale), from the Nacatoch sand on the E. A. Stevens place, 1 4/5 miles northeast of Quinlan, Hunt County. The species listed below are recognizable on the surface shown; on opposite side of slab. This specimen was collected and (U.S.G.S. coll. 16171; U.S.N.M. no. 76344.) 1. N ucula sp. 2. Nemodon eufaulensis Gabb? 3. Breviarca plummeri, n.sp. 4. Crassatella quinlanensis, n.sp. *5. Lucina mattiformis, n.sp. 6. Lucina sp. number marked with asterisk is donated by Mr. F. B. Plummer. 7. Cardium (Trachycardium) eufaulense huntanum, n.var. 8. Cyprimeria depressa Conrad. 9. Tellina munda, n.sp. 10. Cymbophora sp. 11. Corbula rockensis?, n.sp. 12. Creonella triplicata Wade. 13. Turritella trilira Conrad. 14. Anchura caddoensis, n.sp. 15. Unidentified gastropod. 16. Paladmete corbuliformis, n.sp. 17. Ringicula pulchella Shumard. nlverelty of Texas Publlcatlon 4101 Plate 28 The Uni-versity of Texas Publication No. 4101 PLATE 29 PAGB Crassatella vadosa bexarensis, n.var. ------------------------------------------------------------------------------------178 l, 2. Views of the holotype (U.S.G.S. coll. 7721; U.S.N.M. no. 76548) from the Kemp clay on Cibolo Creek, 1112 miles west of Zuehl, in Bexar County. 3-5. Views of three paratypes (U.S.N.M. no. 76549) from the same locality. Crassatella vadosa manorensis, n.var. --------------------------------------------------------------------------------------------177 6, 7. Views of the holotype (U.S.G.S. no. 13861; U.S.N.M. no. 76544) from the Kemp clay in a field 31,4 miles east Ly north of Manor, Travis County. 8, 9. Views of a paratype (U.S.G.S. coll. 14139; U.S.N.M. no. 76545) from the Kemp clay in a branch, 1h mile south of McLeod School, 61h miles southwest of Currie, Navarro County. Crassatella vadosa chatfieldensis, n.var. ---------------------------------------------------------------------------------------------178 10, 11. Views of the holotype (U.S.G.S. coll. 14117; U.S.N.M. no. 76547) from the Naca· toch sand near public road 3/5 to 4/5 mile north-northeast of Chatfield, Navarro County. Crassatella sp.b. _________ __ ----- -----------------------··-----------------------------------·- ---------------------------------------------180 12. A left valve (xl1h) from the Corsicana marl on San Marcos River, 1h mile below Martindale, Caldwell County. (U.S.G.S. coll. 15527; U.S.N.M. no. 76561.) Crassatella sp.a. ___________________________________·----·---------·----------------------------------------------------------------------------------180 13. A left valve (xl1h) from the Corsicana marl on San Marcos River, 1h mile below Martindale, Caldwell County. (U.S.G.S. coll. 7621; U.S.N.M. no. 76558.) The Unlver•lty of Texa• Publlcatlon 4101 Plate 29 The University of Texas Publication No. 4101 PLATE 30 P1n Titanosarcoli tes oddsensis Stephenson ____ _____ _. ____ ------------------------------------------------------------------------------------l~ Antero-ventral view (about x2/3) of holotype (U.S.G.S. coll. 17373; U.S.N.M. no. 75979), from the Kemp day in a field, 1 mile west by south of Odds (Lime­stone County), in Falls County. •• Unlveralty of Texaa Publlcatlon 4101 Plate 30 The University of Texas Publication No. 4101 PLATE 31 PACE Titanosareolites oddsensis Stephenson ------------------------------------------------------------------------------------------------185 Larger, up-facing cut and polished surface of holotype (about x4/5) : be, body cavity, le, longitudinal canals; lt, longitudinal tubes; ma, anterior myaphore; br, areas to left of irregular black line show broken surfaces of shell not in· eluded in polished surface. The Unlveralty of Texas Publlcatlon 4101 Plate 31 The University of Texas Publication No. 4101 PLATE 32 PAGE Titanosarcoli tes oddsen sis Step hen son _________________ -----------------------------------------------------------------------------185 I. Smaller up-facing cut and polished surface of holotype (about x6/7) : be, body cavity; s, fragments of septa in body cavity; le, longitudinal canals; ma, anterior myaphore with "stretched" canals; mp, posterior myaphore with stretched canals, badly crushed; it, longitudinal tubes. T itanosa rcoUtes ? sp. ________________ ---------------------------------------------------------------------------------------------------· 186 2. Incomplete specimen showing incurved beak and broken, distal ends of longitudinal canals. (U.S.G.S. coll. 518; U.S.N.M. no. 20903.) 3. Opposite side of the same specimen showing body cavity and longitudinal canals. 4. Gutta-percha squeeze of body cavity shown in figure 3. The University of Texas Publication 4101 Plate 32 1 The University of Texas Publication No. 4101 PLATE 33 PACE Sauvage sia? hilli, n .sp. --------------------------·----------------------------------------------------------------------------------------------------187 I. Top view of the holotype (U.S.G.S. coll. 16671; U.S.N.M. no. 76575) from the Corsicana marl on Salado Creek at east edge of San Antonio, Bexar County. Lucina pa rvil ineata Shum a rd _______________________________________________________________________ -----------------------------------------------189 2,3. Views (xl%) of the neotype (U.S.G.S. coll. 763~ U.S.N.M. no. 76577) from the Nacatoch sand near Corsicana, Navarro County. 4, 5. Views (xl% ) of a specimen (U.S.N.M. no. 76578) from the same locality. 6. A left valve (xl % ) from the Nar.atoch sand on Postoak Creek at north edge of Corsicana, Navarro County. (U.S.G.S. coll. 518; U.S.N.M. no. 76579.) Lucina mattiform is, n. sp. ____________---------------------------------------------------------------------------------------------------------------190 7. Holotype (xl % ) , a left valve (U.S.G.S. coll. 14103; U.S.N.M. no. 76580), from the Nacatoch sand on the Dallas road, 3/5 mile west of Kaufman, Kaufman County. Lucina linearia, n.sp. -----------------------------------------------------------------------------------------------------------------------------------190 8. Holotype (x6), a left valve (U.S.G.S. coll. 7601; U.S.N.M. no. 76582), from the Kemp clay on Colorado River at Webberville, Travis County. 9. Interior (x3) of a paratype (U.S.N.M. no. 76583) from the same locality. Titanosarcolites? sp. ----------------------------------------··--------------·-----·-----·-------------------------------------------------------------186 10. A large fragment from the Nacatoch gand on the Dallas highway, 3/5 mile west of Kaufman, Kaufman County. (U.S.G.S. coll. 14098; U.S.N.M. no. 75891.) The University of Texas Publication No. 4101 PLATE 34 PACE Lucina seminalis, n.sp. ------------------------------------------------------------------------------------------------------------------------191 1, 2. Views (x3) of the holotype (U.S.G.S. coll. 17366; U.S.N.M. no. 76588) from the Nacatoch sand near U. S. Highway 75, 4 miles north of Corsicana, Navarro County. Lucina oleodorsum, n.sp. ------------------------------___---------------------------------------------------------------------------·-·······-192 3. Holotype (x3), a right valve (U.S.G.S. coll. 17366; U.S.N.M. no. 76589), from the Nacatoch sand near U. S. Highway 75, 4 miles north of Corsicana, Navarro County. Lucina chatfieldana, n.sp. --------------------·---------------------------------------------------------------------·-----·-·-··--···-········-··· 191 4. Holotype (x2), a left valve (U.S.G.S. coll. 7569; U.S.N.M. no. 76585), from the Nacatoch sand in a field south of Chatfield, Navarro County. 5. A paratype (x2), a right valve (U.S.N.M. no. 76586), from the same locality. Unicardiuni? sp. ___ -------------------------------___ --. ..-----------··----------------------------------------------------------------------------·--······ 192 6, 7. Views of a right valve from the Corsicana marl in a bluff on Guadalupe River, 1 3/10 miles north of McQueeney. (U.S.G.S. coll. 15524; U.S.N.M. no. 76593.) Scintilla? ramoni, n.sp. --------------------------------------------------------------·------------------------------------·-·-·--···----··········· 193 8. Right valve of holotype (U.S.G.S. coll. 761; U.S.N.M. no. 76594) from the Naca· toch sand near Kaufman, Kaufman County. Sauvagesia? hilli, n.sp. --------------------------------------------·--------------------------------------------------------------------------····-187 9. View of holotype (U.S.G.S. coll. 16671; U.S.N.M. no. 76575) on side to right of the siphonal bands, from the Corsicana marl on Salado Creek at east edge of San Antonio, Bexar County. Cardium (Granocardium) bowenae, n.sp. --------------------------·-----------------------------------------····-·-·-··-------------198 10. Squeeze of external mold (xl1h) of holotype, a left valve (U.S.G.S. coll. 12923; U.S.N.M. no. 76608), from the Nacatoch sand on the Dallas highway, 3/5 mile west of Kaufman, Kaufman County. 11. Posterior view (xl1h) of the same squeeze. 12. Internal mold of the holotype. Cardium (Ethmocardium) we/Leri, n.sp. ----------------------------------------------------··------------------·-·--------------195 13. Holotype (xl%), a right valve (U.S.G.S. coll. 763; U.S.N.M. no. 76600), from the Nacatoch sand near Corsicana, Navarro County. 14, 15. Views (xl1h) of a paratype (U.S.G.S. coll. 518; U.S.N.M. no. 76602a), from the Nacatoch sand on Postoak Creek at north edge of Corsicana. 16. Interior (xl%) of a paratype (U.S.N.M. no. 76602b) from the same locality. 17. Internal mold (xl1h) of a paratype (U.S.G.S. coll. 763; U.S.N.M. no. 76601), from the Nacatoch sand near Corsicana. Plate 34 The University of Texa Publlcatlon 4101 The University of Texas Publication No. 4101 PLATE 35 PACE Cardium ( G ranocardi um) deltanu m, n.sp. ----------------------------------------------------------------------------------·-·· 196 1-3. Views (x2) of the external surface of the holotype (U.S.G.S. coll. 14062; U.S.N.M. no. 76604) from the Neylandville marl on Texas Midland R.R., ¥.z mile north of Cooper, Delta County. 4. Internal mold of right valve of holotype. Brevicardium tenue, n.sp. ------------------------------------------------------------------------------------------------------------------·-205 5. Holotype (x5), a right valve (U.S.G.S. coll. 16170; U.S.N.M. no. 76647), from the Neylandville marl on the Corsicana road, 2¥.z miles no11h of Corbet, Navarro County. Brevicardium marcosense, n.sp. -------------------------------------------------------------------------------------------------------· 206 6. Holotype (x5), a left valve (U.S.G.S. coll. 15527; U.S.N.M. no. 76650) from the Corsicana marl on San Marcos River, % mile below Martindale, Caldwell County. Brevicardium guadalupense, n.sp. -------------------------------------------------------------------------------------205 7, 8. Views (x3) of the holotype (U.S.G.S. coll. 16668; U.S.N.M. no. 76649) from the Kemp clay near public road, 2 miles south-southeast of Schumannsville, Guadalupe County. Sau t'age sia? hilli, n.sp. __________-----------------------------------------------------------------------------------------------------------187 9. Holotype (U.S.G.S. coll. 16671; U.S.N.~L no. 76575) on side showing the supposed siphonal bands (E and S), from the Corsicana marl on Salado Creek at east edge of San Antonio, Bexar County. The Unlveralty of Texaa Publlcatlon 4101 Plate 35 4 The University of Texas Publication No. 4101 PLATE 36 PACE Cardium ( G ranocardium) rossae, n.sp. ------------------------------------------------------------------------------197 1, 2. Views (xl1h) of the holotype, a right valve (Tex. Bu. 17300; U.S.N.M. no. 76606), from the Neylandville marl on the Corsicana road, 2% miles north of Corbet, Navarro County. Cardium ( G ranocardium) tholi, n.sp. -----------------------------------------------------------------------------------------------199 3. Holotype, a right valve (U.S.G.S. coll. 762; U.S.N.M. no. 76609), from the Nacatoch sand near Chatfield, Navarro County. Cardium (Trac h ycardium) e u faul e nse hun tanum, n. var. --------------------------------------------------------------200 4. Holotype, a right valve (U.S.G.S. coll. 12925; U.S.N.M. no. 76632), from the Nacatoch sand on the Guthrie place, I% miles west of Campbell, Hunt County. B revicardium fragile, n.sp. -------------------------------------------------------------------------· ----------------------------------204 5. Holotype (x6), a left valve (U.S.G.S. coll. 7f1l; U.S.N.M. no. 76644), photographed with coating, from the Owl Creek formation on Owl Creek, Tippah County, Mississippi. 6. The same photographed without coating. 7. Interior (x3) of the holotype. 8. Drawing of hinge (x6) of a left valve from Owl Creek. Sauvagesia? hilli, n.sp. --------------------------------------------------------------------------------------------------------------------187 9. Holotype (U.S.G.S. coll. 16671; U.S.N.M. no. 76575) on side to left of siphonal bands ( E and S) , from the Corsicana marl on Salado Creek at east edge of San Antonio, Bexar County. Plate 36 The University of Texas Publication 4101 508 The University of Texas Publication No. 4101 PLATE 37 PAGE Isocardia shumardi, n.sp. ___ ____------------------------____ -----------------------------------------------------------------------------------207 I. Holotype, a left valve (U.S.G.S. coll. 763; U.S.N.M. no. 20905), from the Nacatoch sand near Corsicana, Navarro County. 2, 3. Views of a paratype, a right valve (U.S.G.S. coll. 16168; U.S.N.M. no. 76659), from the Nacatoch sand on U.S. Highway 75, 3 1/5 miles north of Corsicana, Navarro County. Isocardia bulbosa, n.sp. _____________ ____________.___________ .__ -----------------------------------------------------------------------------------206 4, 5. Views (x2) of the holotype (U.S.G.S. coll. 762; U.S.N.M. no. 76653) from the Nacatoch sand ntar Chatfield, Navarro County. Jsocardia irelandi, n.sp. _________ ____ _________________ _ ___-----------------------------------------------------------------------------------------207 6. Holotype (xl%), a left valve (U.S.G.S. coll. 16170; U.S.N.M. no. 76657), from the Neylandville marl on the Corsicana road, 21h miles north of Corbet, Navarro County. Isocardia hendersoni, n.sp. ________________-------------------_ ___--------------------------·-------------------------------------------------------207 7, 8. Views (xl1h) of the holotype (U.S.G.S. coll. 763; U.S.N.M. no. 76655) from the Nacatoch sand near Corsicana, Navarro County. Cardium ( Granocardium) tippanum (Conrad) -----------------------------------------------------------------------------·· 199 9-11. Views of the neotypc (U.S.G.S. coll. 707; U.S.N.M. no. 76611) from the Owl Creek formation on Owl Creek, Tippah County, Mississippi. 12. A left valve from the Corsicana marl on the San Antonio road, 6 miles east of Castroville, in Bexar County. (U.S.G.S. coll. 16156; U.S.N.M. no. 76614.) Durania? sp. _____ ______ __ -------------·-_____ .________------------------------------------------------------------------------------------------------------· 188 13. View of a lower valve on side to left of the siphonal hands, from the Neylandville marl in a field, 3% miles west-northwest of Corsicana, Navarro County. (U.S.G.S. coll. 16166; U.S.N.1\1. no. 76576.) Plate 37 The University of Texas Publication No. 4101 PLATE 38 PAGE Cardium ( Pachycardiu.m) wadei, n.sp. ---·---------------·------------------------------------------------------------194 l, 2. Views of a para type, a left Yalve ( U.S.G.S. coll. 763; U.S.N.:M. no. 76596), from the Nacatoch sand near Corsicana, Navarro County. Cardium ( Granocardium) sp. -------------------------·-----------------------------------------------------------------·--201 3. Squeeze (xl1h) of part of the external mold of a right valve from the Neyland· ville marl on the Corsicana road, 2% miles north of Corbet, Navarro County. (U.S.G.S. roll. 16170; U.S.N.1\1. no. 76643.) 4. Internal mold of the same specimen. Aphrodina? navarroa.na, n.sp. -----------------·---------------------------------------------------------------------210 5. Holotype {x2), a left valve (U.S.G.S. coll. 16170; U.S.N.M. no. 76662), from the Neylandville marl on the Corsicana road, 21h miles north of Corbet, Navarro County. 6. Hinge (x3) of the holotype. Durania? sp. ----------------------------------------------------------------------------188 7. View of a lower valve on the side of the siphonal bands, from the Neylandville marl in a field, 31h miles west-northwest of Corsicana, Navarro County. (U.S.G.S. coll. 16166; U.S.N.M. no. 76576.) Plate 38 The University of Texas Publlcatlon 4101 The University of Texas Publication No. 4101 PLATE 39 PAGI A phrodina tippana Conrad -----------------------------------------------------------------------------------------------------------------------208 1. Hinge of a left valve from the Naratoch sand near Kaufman, Kaufman County. (U.S.G.S. roll. 761; U.S.N.1\L 76661.) 2, 3. Right and left valves from the same locality. Cardium (Pachycard i um) wad ei, n.sp. -------------------------------------------------------------------------------194 4, 5. Views of the holotype, a right valve (U.S.G.S. coll. 763; U.S.N.M. no. 76595), from the Nacatoch sand near Corsicana, Navarro County. 6. Drawing of a small left valve from the same locality. C yclorisma? pum i la, n.sp. ______________________ ----------------------------------------------------------------------------------------218 7, 8. Views (x2) of the holotype (U.S.G.S. coll. 762; U.S.N.M. no. 76673) from the Nacatoch sand near Chatfield, Navarro County. The University of Texas Publication No. 4101 PLATE 40 PAGE Cy prim.eria alta Conrad ------------------------------------------------------------------------------------------------------------· 212 1. A topotype, a left valve (U.S.G.S. coll. 707; U.S.N.M. no. 76694), from the Owl Creek formation on Owl Creek, 21h miles northeast of Ripley, Tippah County, Mississippi. 2. Dorsal view of a large specimen from the Kemp clay near a public road about 2 2/5 miles southeast of Manor, Travis County. (U.S.G.S. coll. 18196; U.S.N.M. no. 76665.) Cyprimer:ia de pressa Conrad __ _____ __ __ ------------------------------------------------------------------------------------------------------211 3. A left valve from the Nacatoch sand on the Guthrie place, 1% miles west of Campbell, Hunt County. (U.S.G.S. coll. 12925; U.S.N.M. no. 76663.) Cy primeria coonensis, n.sp. ---------------------------------------------------------------------------------------------------------------------214 4. A right valve from the Nacatoch sand near Kaufman, Kaufman County. (U.S.G.S. coll. 761; U.S.N.M. no. 76666.) A phrodina tippana Conrad ___________ __ -----------------------_______________ -----------------------------------------------------------------208 5, 6. Views of a right valve from the Nacatoch sand near Kaufman, Kaufman County. (U.S.G.S. coll. 761; U.S.N.M. no. 76661.) Linearia pectinis, n.sp. ________________________________________________________________ -------------------------------------------------------------222 7. Holotype, a right valve (U.S.G.S. coll. 7637; U.S.N.M. no. 76696), from the Corsi· cana marl in a bluff on Guadalupe River, 1 3/10 miles north of McQueeney, Guadalupe County. Linearia wieserae, n.sp. -----------------------------------------------------------------------------------------------------------------------------222 8. Holotype, a left valve (U.S.G.S. coll. 763; U.S.N.M. no. 76695), from the Nacatoch sand near Corsicana, Navarro County. The University of Texas Publication 4101 Plate 40 The University of Texas Publication No. 4101 PLATE 41 PACE Cyprimeria alta Conrad --------------------------------------------------------------------------------------------------------------------------212 1, 2. Views of the neotype, a right valve (U.S.G.S. coll. 707; U.S.N.M. no. 76664), from the Owl Creek formation on Owl Creek, 2% miles northeast of Ripley, Mississippi. 3. Interior of a left vah-e from the same locality. 4. Left vah-e of a large specimen from the Kemp clay near a public road 2 2/5 miles southeast of 1\Ianor, Travis County. (U.S.G.S. coll. 18196; U.S.N.M. no. 76665). TelIin a? m areas ensis: n.sp. ________________ -------------------------------____-------------------------------------------------------------------220 5, 6. Squeeze (xl and :x~) of the external mold of the holotype, a ri~ht valve (U.S.G.S. coll. 7621; U.S.N.1\1. no. 76682), from the Corsicana marl on San Marcos River, ~2 mile below Martindale, Caldwell County. TelIina? pat ul a, n.sp. -------------------------------------------------------------------------------------------------------------------------------220 7. Holotype ( x I~·~), the internal mold of a right valve with some shell material adher· ing (U.S.G.S. roll. 16170: U.S.N.1\L no. 76683), from the Neylandville marl on the Corsicana road, 21,~ miles north of Corbet, Navarro County. 8. Internal mold ( xE~) of the left valve of a paratype ( U.S.G.S. coll. 16164; U.S.N.M. no. 76684) from the Neylandville marl on the Drane road, 5 miles west-southwest of Corsicana, Narnrro County. I..inearia sp. ------------------------------------------------------------------------------------------------------------------------·------------------------224 9. Fragment of left rnh-e (xl % ) from the Nacatoch sand on Postoak Creek at north edAe of Corsicana, Navarro County. ( U.S.G.S. coll. 518; U.S.N.M. no. 20949.) Plate 41 Th• Unlveralty of Texaa Publlcatlon 4101 518 The University of Texas Publication No. 4101 PLATE 42 Tellina munda, n.sp. ______________________-----------------------------------------------------------------------------------------------------------­1-3. Views (xl112) of the holotype (U.S.G.S. coll. 762; U.S.N.l\t no. 76678) from the Nacatoch sand near Chatfield, Navarro County. 4. Internal mold (x2) of the right side of a paratype (U.S.N.M. no. 76679) from the same locality. 5. A paratype (x4), a right valve (U.S.G.S. coll. 7573; U.S.N.M. no. 76680), from the Nacatoch sand near a public road, 5 miles south-southwest of Corsicana, Navarro County. Linearia navarroana, n.sp. ------------------------------------------------------------------------------------------------------------­ 6. Holotype, internal mold of right valve with some shell adhering (U.S.G.S. coll. 7570; U.S.N.M. no. 76699), from the Nacatoch sand in public road, 1h mile east of Chatfield, Navarro County. 7. Left valve of a paratype (U.S.G.S. coll. 7571; U.S.N.1\1. no. 76700) from the Nacatoch sand in a public road, % mile east of Corsicana, Navarro County. Linearia cribelli, n.sp. _________ . __________-----------_------------------------------------------------------·-------------------------------------­ 8. Holotype (x3), a right valve (U.S.G.S. coll. 7621; U.S.N.M. no. 76698), from the Corsicana marl on San l\farcos River, % mile below Martindale, Caldwell County. Tenea parilis Conrad _____________________________________ ____ -------------------------------------------------------------------------------_ ______ 9. Left valve (x2) from the Nacatoch sand on Postoak Creek at north edge of Corsi­cana, Navarro County. (U.S.G.S. coll. 518; U.S.N.M. no. 76672.) 10. Internal mold of right valve from the same locality. 11. Hinge (x2) of a right valve from the Owl Creek formation on Owl Creek, 21h miles northeast of Ripley, Tippah County, Mississippi. (U.S.G.S. coll. 707; U.S.N.M. no. 76671.) 12. Hinge (x2) of a left valve from the Ripley formation at Bullocks old mill near Dumas, Tippah County, Mississippi. (U.S.G.S. coll. 708; U.S.N.M. no. 20752.) Legumen ellipticum Conrad --------------------------------------------------------------------------------------------------------------------­ 13. Left valve of a topotype from the Owl Creek formation on Owl Creek, Tippah County, Mississippi. (U.S.G.S. coll. 594; U.S.N.M. no. 76668.) 14, 15. Hinges (xl %) of left and right valves of topotypes from the same locality. (U.S.G.S. coll. 707; U.S.N.l\L no. 76667.) 16. Left valve of a specimen from the Nacatoch sand on the Dallas highway, 3/5 mile west of Kaufman, Kaufman County. (U.S.G.S. coll. 14103; U.S.N.M. no. 76669.) 17. Dorsal view (x1%) of the same specimen. 18. A right rnh-e from the same locality. 19. Part of internal mold (xl ~~) of a right valve from the Nacatoch sand near Chat· field, Navarro County. (U.S.G.S. coll. 762, U.S.N.M. no. 76670.) PACE 219 223 223 217 215 The University of Texas Publication 4101 Plate42 PLATE 43 PAGE Leptosolen? quadrilaterus, n.sp. ----------------------------··--------------------------··-------__ ---------·-------------------------------· 228 1. Holotype (x2), a right valve (U.S.G.S. coll. 761; U.S.N.M. no. 76709), from the Nacatoch sand near Kaufman, Kaufman County. Leptosolen ? Levis, n.sp. ----------------------------------------______---------------------------_ _ ------__________ ----------------------------·-· 228 2. Holotype (xl1;2), a right valve (U.S.G.S. coll. 14117; U.S.N.M. no. 76711), from the Nacatoch sand near public road, 3/5 to 4/5 mile northeast of Chatfield, Navarro County. Leptosolen? linguliformis, n.sp. ----------------------_ __ _ ____________-------------------------------------------------------------------·-··· 228 3. Squeeze (xl%) of the holotype, an external mold of a right valve (U.S.G.S. coll. 13832; U.S.N.M. no. 76710), from the Corsicana marl on the Mexia road, 2 4/5 miles east of Cooledge, Limestone County. Leptosolen biplicatus Conrad -----------------------------------------------------------------------------------------------------------------226 4, 5. Left valves from the Nacatoch sand near Corsicana, Navarro County. (U.S.G.S. coll. 763; U.S.N.M. no. 76708.) Solym.a gardnerae, n.sp. --------------------------------····-----------------------------------------· --------------------------------------------·---·· 225 6. Left valve of the holotype (U.S.G.S. coll. 762; U.S.N.M. no. 21048) from the Nacatoch sand near Chatfield, Navarro County. 7. Dorsal view (x l 1h) of the holotype. Cymbophora scabellum, n.sp. -------------------------------------------------------------------------------------------------------------------· 229 8. Holotype, a left valve ( U.S.G.S. coll. 14103; U.S.N.M. no. 76713), from the Naca­toch sand in a field, 3/5 mile west of Kaufman, Kaufman County. 9. Internal mold of a paratype (U.S.N.l\t no. 76714), a right valve from the same locality. Cymbophora berryi Gardner ------------------------------------------------------------------------------------------------------------------· 232 10. Holotype (xl%), a right valve (U.S.G.S. coll. 761; U.S.N.M. no. 76721), from the Nacatoch sand near Kaufman, Kaufman County. Cymbophora subtilis, n.sp. __ _______________ _________ __ ____ ·-----------------------------------------------------------------------------------------230 11. Left valve (xl%) of the holotype (U.S.G.S. coll. 761; U.S.N.M. no. 76715) from the Nacatoch sand near Kaufman, Kaufman County. Cymbophora? simpsonensis, n.sp. _________ ________________________ ____ ----------------------------------------------------------------------233 12. Holotype, a left valve (U.S.G.S. coll. 7546; U.S.N.M. no. 76723), from the Naca· toch sand on public road, 2 miles southwest of Kaufman, Kaufman County. Cyrnbophora cancellosa, n.sp. ___________.____ __ _---------------------------------------------------------------------------------------------231 13, 14. Views (xl1h) of the holotype, a left valve (U.S.G.S. coll. 518; U.S.N.M. no. 76718), from the Nacatoch sand on Postoak Creek at north edge of Corsicana, Navarro County. 15. A paratype, a left valve (U.S.G.S. coll. 763; U.S.N.M. no. 76719), from near Corsicana. Cymbophora infiata, n.sp. ______________ _______---------------------------------------------------------------------------------------------------232 16, 17. Views of squeeze of external mold of holotype (U.S.G.S. coll. 16162; U.S.N.M. no. 76722), a left valve from the Nacatoch sand on the Stevens place, 1 4/5 miles northeast of Quinlan, Hunt County. Solyma? parva, n.sp. ----------------------------------------------------------------------------------------------------------------------226 18. Left valve (x2) of the holotype (U.S.G.S. coll. 762; U.S.N.M. no. 76706) from the Nacatoch sand near Chatfield, Navarro County. 19. Dorsal view (x4) of the holotype. The University of Texas Publlcatlon 4101 Plate 43 6 7 9 4 The University of Texas Publfoation No. 4101 PLATE 44 PACE X ylophage!la whitn eyi, n.sp. ----------------------------------------------------------------------------------------------------------------248 1-3. Views (x3) of the holotype (U.S.G.S. coll. 763; U.S.N.M. no. 76759) from the Nacatoch sand near Corsicana, Navarro County. Ph oladidea ragsdalensis, n.sp. ---------------------------------------------------------------------------------------------------246 4, 5. Views (x3) of the holotype (U.S.G.S. coll. 12925; U.S.N.M. no. 76756) from the Nacatoch sand on the Guthrie place, 1% miles west of Campbell, Hunt County. Corbula u:oodi, n.sp. ----------------------------------------------------------------------------------------------------------239 6, 7. Views (x3) of the holotype (U.S.G.S. coll. 763; U.S.N.M. no. 76740), from the Nacatoch sand near Corsicana, Navarro County. l'orbu.la sp. _____________________ ------________ --------________________ ------------------------------------------------------------------------240 8. A left valve (x3) from the Nacatoch sand near Kaufman, Kaufman County. (U.S.G.S. coll. 761; U.S.N.l\I. no. 21033.) Corbu!a in fiat a, n.sp. -----------------------------------------------------------------------------------------------------------------------239 9, 10. Views (x4) of the holotype (U.S.G.S. coll. 761; U.S.N.M. no. 76742) from the Nacatoch sand near Kaufman, Kaufman County. Corbula linteroidea, n.sp. __________________________________ -------------------------------------------------------------------------------------238 11-13. Views (x-1) of the holotype (U.S.G.S. coll. 763; U.S.N.:M. no. 76738) from the Nacatoch sand near Corsicana, Navarro County. Corbula U'illiardi Wade __ ------------------------------------------------------------------------------------------------------------------235 14. A right valve (x4) from the Nacatoch sand near Kaufman, Kaufman County. (U.S.G.S. coll. 761; U.S.N.l\I. no. 76731.) Cor bula roekensis, n.sp. ______________ ------------------------------------------------------------------------------------------237 15. Holotype (x3), a right valve (U.S.G.S. coll. 9545; U.S.N.M. no. 76733), from the Nacatoch sand on Walton lease of Houston Oil Company, 3 miles northeast of Corsicana, Navarro County. Corbula crassiplica Gabb --------------------------------------------------------------------------------------------------234 16. A right valve (x4) from the Nacatoch sand on the Dallas highway, 3/5 mile west of Kaufman, Kaufman County. (U.S.G.S. coll. 14098; U.S.N.M. no. 76730.) 17. Specimens of this species (x2), marked with arrows, on a piece of rock from the same locality. Corbu!a torta, n.sp. _________________________________ __ __________ ----------------------------------------------------------------------236 18-20. Views (x3) of the holotype, a right valve (Tex. Bu. 17300; U.S.N.M. no. 76732), from the Neylandville marl on the Corsicana road, 2% miles north of Corbet, Navarro County. Corbula su bradiata texana, n. var. ---------------------------------------------------------------------------------------237 21. Holotype (x6), a right valve (U.S.G.S. coll. 7573; U.S.N.M. no. 76735), from the Nacatoch sand near a public road, 5 miles south-southwest of Corsicana, Navarro County. 22. Right valve (x5), a paratype (U.S.G.S. coll. 9545; U.S.N.M. no. 76736), from the Nacatoch sand on Walton lease of Houston Oil Company, 3 miles northeast of Corsicana, Navarro County. The Unlveralty of Texas Publlcatlon 4101 Plate 44 The University of Texas Publication No. 4101 PLATE 45 PACE Pholas? pectorosa Conrad ----------------------------------------------------------------------------------------------------------------------251 I, 2. Views (xl%) of a specimen from the Corsicana marl near a second-class road, 1 9/10 miles northeast of Quinlan, Hunt County. (U.S.G.S. coll. 17381; U.S.N.M. no. 76764.) Panope subplicata Shumard ____ ___ ____ -----------·______ __ __ -------------------------------------------------------------------------------241 3. Incomplete left valve of the neotype ( U.S.G.S. coll. 762; U.S.N.M. no. 76750) from the Nacatoch sand near Chatfield, Navarro County. 4. An incomplete left valve from the same locality. (U.S.N.M. no. 21095.) 5, 6. Views of a specimen from the Nacatoch sand near Corsicana, Navarro County. (U.S.G.S. coll. 763; U.S.N.M. no. 76751.) Ramsetia whitfieldi, n.sp. ___________---------------____ __ _ _______·-----------------------------------------------------------------------251 7. Holotype, a left valve (U.S.G.S. coll. 761; U.S.N.M. no. 76762), from the Naca· toch sand near Kaufman, Kaufman County. 8, 9. Views of a paratype (U.S.N.M. no. 76763) from the same locality. Plate 45 The University of Texas Publlcatlon 4101 7 9 The University of Texas Publication No. 4101 PLATE 46 PAGE Goniochasma seaphoides, n.sp. ______________________ -----------------------------------------------------------------------------------------249 I. Left valve (x2) of the holotype (U.S.G.S. coll. 763; U.S.N.M. no. 76760) from the Nacatoch sand near Corsicana, Navarro County. 2. Enlargement (xlO) of a selected part of the surface of the holotype. 3. The holotype (xl) in boring in fossil wood. 4. Dorsal view (x2) of a paratype (U.S.N.M. no. 76761) from the same locality. Castrochaena ripleyana, n.sp. ---------------------------------------------------------------------------------------------------------------244 5, 6. Views (xl1h) of the holotype (U.S.G.S. coll. 707; U.S.N.M. no. 76752) from the Owl Creek formation, 2% miles northeast of Ripley, Tippah County, Mississippi. 7. Front end view (x3) of the holotype. 8-11. Tubes with a shell in place in one of them, from the same locality. (U.S.G.S. coll. 75; U.S.N.M. no. 76753.) 12. A tube from the Naratoch sand near Kaufman, Kaufman County. (U.S.G.S. coll. 761; U.S.N.M. no. 20967.) 13. A specimen (xl1h) from the Corsicana marl in a public road, 114, miles south by east of Oak Grove, Bowie County. (U.S.G.S. coll. 13568; U.S.N.M. no. 76755.) 14. Front end view (x3) of the same ~pecimen. Dentalium vaughani, n.sp. --------------------------------------------------------------------------------------------------------------------------252 15. Side view (x3) of holotype (U.S.G.S. coll. 16170; U.S.N.M. no. 76765) from the Neylandville marl on the Corsicana road, 21h miles north of Corbet, Navarro County. Dentalium navarroi, n.sp. ------------------------------------------------------------------------------------------------------------------------2.53 16. Side view (x3) of holotype (U.S.G.S. coll. 762; U.S.N.M. no. 76767) from the Nacatoch sand near Chatfield, Navarro County. 17. Fragment (x3), a paratype (U.S.N.M. no. 76768), from the same locality. Dentalium leve Stephenson --------------------------------------------------------------------------------------------------------------------253 18, 19. Views (x3) of a specimen from the Kemp clay on the Thompson place, 4% miles northeast of Roane, Navarro County. (U.S.G.S. coll. 12922; U.S.N.M. no. 76700.) Dentalium paupereulum Meek and Hayden ____ ____________________ -----------------------------------------------------------------254 20, 21. Views (x3) of a specimen from the Neylandville marl on the Corsicana road, 21h miles north of Corbet, Navarro County. (U.S.G.S. coll. 16170; U.S.N.M. no. 76771.) Cadulus obnutus (Conrad) -------------------------------------------------------------------------------------------------------------------255 22. A specimen (x6) from the Nacatoch sand on the Stevens place, 1 4/5 miles north· east of Quinlan, Hunt County. (U.S.G.S. coll. 16162; U.S.N.M. no. 76783.) Cadulus coonensis, n.sp. ________________ _ ____________________ -----------------------------------------------------------------------------------256 23. A specimen (x6) from the Nacatoch sand on the Watkins place, 3 miles north of Corsicana, Navarro County. (U.S.G.S. coll. 9552; U.S.N.M. no. 76785.) The University of Texas Publication 4101 Plate46 The University of Texas Publication No. 4101 PLATE 47 PACE Acmaea? occidentalis (Hall and Meek) ? -----------------------------------------------------------------------------------------------256 l. A specimen from the Kemp clay on Cibolo Creek, l 1h miles west of Zuehl, in Bexar County. (U.S.G.S. rnll. 7721; U.S.N.M. no. 76786.) Weeksia lubbocki, n.sp. --------------------------------------------------------------------------------------------------------------------------------258 2-4. Views (x2) of the holotype (U.S.G.S. coll.• 763; U.S.N.M. no. 20908) from near Corsicana, Navarro County. Pseudomalaxis? patens, n.sp. ----------------------------------------------------------------------------------------------------------------258 5-7. Views (x2) of the holotype (U.S.G.S. coll. 763; U.S.N.M. no. 76787) from the Nacatoch sand near Corsicana, Navarro County. Calliomphalus bellulus, n.sp. ________ _ __ ______ _____ ____-------------------------------------------------------------------------------------259 8, 9. Views (x3) of the holotype (lJ.S.G.S. rnll. 16170; U.S.N.M. no. 76791) from the Neylandville marl on the Corsicana road, 2% miles north of Corbet, Navarro County. Calliom phalu.s microcancelli, n.sp. ______________ __ __ __ __ _____________ --------------------------------------------------------------------260 10, 11. Views (x4) of the holotype (U.S.G.S. coll. 16353; U.S.N.M. no. 76793) from the Corsicana marl in a dug well, 7/20 mile south by west of St. Mary's University, Bexar County. 12. Squeeze (x4) of the external mol rn.S.G.S. roll. 155.37: U.S.N.M. no. 76953) from the hase of the Kemp clay on a branch. .3 mile~ south, 30° wrst of Thrall, William· son County. 3, 4. Views (x2) of a paratype (U.S.N.\L no. 76954) from the same locality. Drepanorhilus? martird, n.sp. ··----____ ____.. ___ __ _ __ ___ -----------------------·------·---------------------------------------------306 5. View (x2) of the holotyp<> (li.S.G.S. roll. 762: U.S.N.M. no. 76956) from the Nacatoch sand near Chatfield. Navarro County. Drepanochilus? corbetensis, n.sp. __ ___ 6, 7. Views (x3) of the holotype Nevlandville marl on the County. --··--___ __ --·---------------------------------------------------------------------------------307 (U.S.G.S. coll. 16170: U.S.N.M. no. 76960) from the Corsicana road, 2~~ .miles north of Corbet, Navarro 8. View (x3) of a paratype (U.S.NJ\I. no. 76961) from the same locality. Drepanochilus triliratus~ n.sp. _________ ___________ __ ________________ ..___ _ ___ _ __ ___ ------· -----------------·----------------------------308 9, 10. Views (x2) of the holotype (U.S.G.S. coll. 17368; U.S.N.M. no. 76963) from the Nacatoch sand on State Hip:hway 22~ 2% miles west hy south of Corsicana, Navarro County. Drepanochilus sp. _____ __ _ ____ __ ____..___ _______________ ____ ... -----------------------·----------------------------------------------------------308 11, 12. Yiews (x3) of a specimen from the Neylandville marl on the Corsicana road, 211'2 miles north of Corbet, Navarro County. (U.S.G.S. coll. 16170; U.S.N.M. no. 76964.) Drepanochilus? davisi. n.sp. __ __ __ -----------------------------------------------·--------------------------·----------------------------------307 13. View (x2) of the holotype (U.S.G.S. coll. 763: U.S.N.M. no. 76958) from the Nacatoch sand near Corsicana, Navarro County. 14. Enlargement (x5) of part of the holotype. Drepanochilus? sp. -------------------________________________________________________ -----------------------------------------------------------------309 15. A specimen (x3) from the Neylandville marl on the Corsicana road, 21h miles north of Corbet, Navarro County. (U.S.G.S. coll. 16170; U.S.N.M. no. 76967.) Anchura? sp. ________ _______________ __ -----·· _ ____ ___ __________ ______________ _ ______ ------------------------------------------------------------3M 16. A specimen from the Corsicana marl in a pit ] 4 miles west of San Antonio, Bexar County. (U.S.G.S. coll. 15520; U.S.N.1\I. no. 76939.) Anchura sp. __ __ __ _---------------·-----------· ______ ______ _______________________ ·--------------_ __----------------------·----------------------------304 17. A specimen from the Corsicana marl on the San Antonio road, 6 miles east of Castroville, in Bexar County. (U.S.G.S. coll. 15502; U.S.N.M. no. 76938.) Anchura? hoggi, n.sp. ___ __ ______________-------------------------------------------------·-----------------------·------------------------------303 18, 19. YiPws (xl1h) of the holotype (lJ.S.G.S. coll. 7721; U.S.N.M. no. 76928) from the Kemp clay on Cibolo Creek, l 1h miles west of Zuehl, in Bexar County. 20. Back view (xl ~~) of a paratype (U.S.N.1\L no. 76929) from the same locality. Anchura? sp. _______ ._____________________ ____ _______________·----------------------------------------------------------------------------------------304 21. Back view (xP~) of a specimen from the Corsicana marl in a bluff on Guadalupe River, 1 3/10 miles north of 1\lcQueeney, Guadalupe County. (U.S.G.S. coll. 15524; U.S.N.l\I. no. 76937.) Anchura sp. ------------------------____ _________ _____ ----------------------------_______-----------------------------------------------------------------305 22. A pathologic specimen (xl%) from the Corsicana marl at the preceding locality. (U.S.N.l\L no. 76947.) Th• Unlveralty of Texas Publlcatlon 4101 Plate 57 The University of Texas Publication No. 4101 PLATE 58 PACE Pugnellus robustus, n.sp. -------------------------------------------------------------------------------------------------------------------------312 1. A paratype (U.S.G.S. coll. 7546; U.S.N.M. no. 76977) from the Nacatoch sand in a public road, 2 miles southwest of Kaufman, Kaufman County. 2. A paratype (U.S.G.S. coll. 7547; U.S.N.M. no. 76976) from the Nacatoch sand in a field just north of the preceding. 3, 4. Views of the holotype (U.S.G.S. roll. 761; U.S.N.M. no. 76975) from the Nacatoch sand near Kaufman, Kaufman County. Pugnellus densatus nacatoc hanus, n.var. ------------_----------------------------------------------------------·----------------------310 5, 6. Views of the holotype ( U.S.G.S. coll. 762; U.S.N.M. no. 76971) from the Nacatoch sand near Chatfield, Navarro County. 7. A young shell lacking callus, a paratype (U.S.G.S. coll. 518; U.S.N.M. no. 76973), from the Nacatoch sand on Postoak Creek at north edge of Corsicana, Navarro County. 8. Apical part (x2) of a young shell, a paratype (U.S.N.M. no. 76974), from the same locality. Pteroce re lla poinse ttiform is, n.sp. -------------------------------------------------------------------------------------------------------309 9. Holotype (U.S.G.S. coll. 761; U.S.N.M. no. 76969) from the Nacatoch sand near Kaufman, Kaufman County. 10. Front view of a specimen (U.S.N.M. no. 20994) from the same locality. 11. Back view (xl1h) of a young shell, paratype (Tex. Bu. 17302; U.S.N.M. no. 76970), from the Nacatoch sand, 2 1/10 miles northeast of Chatfield, Navarro County. 12. Back view of a paratype (U.S.G.S. coll. 762; U.S.N.M. no. 21061) from the Naca· toch sand near Chatfield, Navarro County. The University of Texas Publication No. 4101 PLATE 59 PACE Turzdora tuberculata, n.sp. -----------------------------------------------------------------------------------------------------------------------313 1, 2. Views (x3) of the holotype (Tex. Bu. 17300; U.S.N.M. no. 76984) from the Ney­landville marl on the Corsicana road, 2% miles north of Corbet, Navarro County. 3, 4. Views (x3) of a paratype (U.S.N.l\L no. 76985) from the same locality. /1/apulus sp. _____________ _ ___ -----------------------------·__ _ _________ _ ________ ·--------------------------------------------------------------------320 5. Back view (xl 1h) of a specimen from the Corsicana marl on the Mexia road, 2 4/5 miles east of Cooledge, Limestone County. (U.S.G.S. coll. 13832; U.S.N.M. no. 77006.) '!'trapulus sp. -------------------------------------------------------------------------------------------------------------------------------------------------320 6. Back view (xl1h) of a specimen from the Corsicana marl on a public road, 1 4/5 miles north of Tona siding, in Hunt County. (U.S.G.S. coll. 15545; U.S.N.M. no. 77002.) !\.apulus sp. __ __ ___ _ ____________ __ ____________ _ _______ ------------____________________________________________ __ _______ ------------------------__________ 320 7. Cypraea 8, 9. 10. 11. Back view (xl1h) of a specimen from the Corsicana marl in a bluff on Guadalupe River, 1 3/10 miles north of l\IcQueeney, Guadalupe County. (U.S.G.S. coll. 15524; U.S.N.M. no. 77003.) nuciform is, n.sp. _________________________________________ -------------------------------------------------------------------------------314 Views (xl1h) of the holotype (U.S.G.S. coll. 761; U.S.N.M. no. 76988) from the Nacatoch sand near Kaufman, Kaufman County. Back view (xl %) of a paratype (U.S.N.M. no. 21007) from the same locality. Front view (xl1h) of a paratype (U.S.N.M. no. 21007) from the same locality. Cypraea gracilis, n.sp. --------------------------------------------------------------------------------------------------------------------------------314 12, 13. Views (x2) of the holotype (U.S.G.S. coll. 518; U.S.N.M. no. 20894) from the Nacatoch sand on Postoak Creek at north edge of Corsicana, Navarro County. Pyropsis lanhami, n.sp. -----------------------------------------------------------------------------------------------------------------------------315 14-16. Views (xl1h) of the holotype (U.S.G.S. coll. 7721; U.S.N.M. no. 76989) from the Kemp clay on Cibolo Creek, l % miles west of Zuehl, in Bexar County. Pyropsis sp. ____________________________________________________ __________ _ ---------------------------------------------------------------------------316 17. A specimen from the Corsicana marl on the Corsicana road, 6 miles east of Castro­ville, in Bexar County. (U.S.G.S. coll. 15502; U.S.N.M. no. 76991.) Pyro psis sp. -----------------------------------------__ ___________ --------------------------------------------------------______ _ --------------------------316 18. A fragment (x2) from the Corsicana marl in a bluff on Guadalupe River, 1 3/10 miles north of 1\kQueeney, Guadalupe County. (U.S.G.S. coll. 15524; U.S.N.M. no. 76992.) Pyro psis sp. __________________ __ _______________________________________ ______-------------------------------------________________________ --------------316 19, 20. Views (xl1h) of a specimen from the Neylandville marl in a field, 3% miles west· northwest of Corsicana, Navarro County. (U.S.G.S. coll. 16166; U.S.N.M. no. 76990.) Plate 59 The Unlveralty of Texaa Publication 4101 4 3 1 2 5 6 17 12 8 7 11 13 x ~ 18 The University of Texas Publication No. 4101 PLATE 60 PAGE Pinella reticulata, n.sp. -----------------------------------------------------------------------------------------------------------------------324 1, 2. Views (x3) of the holotype (U.S.G.S. 'coll. 7721; U.S.N.M. no. 77020) from the Kemp clay on Cibolo Creek, l % miles west of Zuehl, in Bexar County. Napulus tubereulatus, n.sp. --------------------------------------------------------------------------------------------------------------319 3, 4. Views (x2) of the holotype (U.S.G.S. coll. 763; U.S.N.M. no. 76998) from the Nacatoch sand near Corsicana, Navarro County. 5, 6. Views (x2) of a paratype (U.S.N.M. no. 20911) from the same locality. N apulus octoliratus (Conrad) ? ----------------------------------------------------------------------------------------------------------------320 7, 8. Views (xl1/2) of a specimen .from the Kemp clay in a branch, 1h mile south of McLeod School, 6% miles southwest of Currie, Navarro County. (U.S.G.S. coll. 14139; U.S.N.M. no. 76999.) M edionapus elongatus, n.sp. -----------------------------------------------------------------------------------------------·-----------------·-317 9-11. Views of the holotype (U.S.G.S. coll. 763; U.S.N.M. no. 20945) from the Nacatoch sand near Corsicana, Navarro County. M ediona pus ? sp. ---------------------------------------------------------------------------------------------------------------------·----317 12, 13. Views of a specimen (x3) from the Nacatoch sand on Walton lease of Houston Oil Company, 3 miles northeast of Corsicana, Navarro County. (U.S.G.S. coll. 9545; U.S.N.M. no. 76996.) M edionapus? sp. ----------------------------------------------------------------------------------------------------------------------------------------318 14. Squeeze of external mold of a specimen from base of Corsicana marl near oil-test well of Morgan Oil Company, 2 3/5 miles north by east of Malta, Bowie County. (U.S.G.S. coll. 16159; U.S.N.M. no. 76997.) Sar gana stantoni (Weller) -----------------------------------------------------------------------------------------------------------------· 325 15-17. Views (xl%) of the holotype (U.S.G.S. coll. 762; U.S.N.M. no. 21070) from the Nacatoch sand near Chatfield, Navarro County. Plate 60 The Unlveralty of Texaa Publlcatlon 4101 2 11 8 10 12 13 The University of Texas Publication No. 4101 PLATE 61 PAGE Morea marylandica bella, n.var. ------··------·-------------------------------------------------------------------------------------------------327 l, 2. Views (x2) of the holotype (U.S.G.S. coll. 518; U.S.N.M. no. 77025) from the Nacatoch sand on Postoak Creek at north edge of Corsicana, Navarro County. Morea ma~ylandica languida, n.var. --------------------------------------------------------------------------------------------------------328 3, 4. Views (x2) of the holotype (U.S.G.S. coll. 17366; U.S.N.M. no. 77027) from the Nacatoch sand near U.S. highway 75, 4 miles north of Corsicana. Morea cancellaria crassa, n.var. ------------------------------------------------------------------------------------------------------·------327 5, 6. Views of the holotype (U.S.G.S. coll. 14114; U.S.N.M. no. 77024) from the Naca­toch sand in public road, 2% miles north of Corsicana. Morea caneellaria corsicanensis, n.var. -----------------------------------------------·-----------------------------------------------------326 7, 8. Views of the holotype (U.S.G.S. coll. 518; U.S.N.M. no. 77022) from the Nacatoch sand on Postoak Creek at north edge of Corsicana. 9. Back view of a paratype (U.S.N.M. no. 77023) from the same locality. Hercorhyncus malleiforme, n.sp. -----------------------------------------------------------------··--------------------------------------------321 10, 11. Views of the holotype (U.S.G.S. coll. 7721; U.S.N.M. no. 77008) from the Kemp clay on Cibolo Creek, l % miles west of Zuehl, in Bexar County. Hercorhyncus coronale, n.sp. ________________ --------------------------------------------------------------------·------------------------------323 12, 13. Views (xl1h) of the holotype (U.S.G.S. coll. 17368; U.S.N.M. no. 77014) from the Nacatoch sand on State Highway 22, 21h miles west by south of Corsicana, Navarro County. JIercorhyncus nodosum, n.sp. --------------------------------------------------------------------------------------------------------------------322 14, 15. Views (xl1;2) of the holotype (Tex. Bu. 17300; U.S.N.M. no. 77011) from the Neylandville marl on the Corsicana road, 2% miles north of Corbet, Navarro County. Hercorhyncus mundum, n.sp. ----------------------------------------------------------------------__ ·--------------------------·---------------322 16, 17. Views (xl%) of the holotype (Tex. Bu. 17300; U.S.N.M. no. 77012) from the Neylandville marl on the Corsicana road, 21h miles north of Corbet. IIereorhyncus vadosum, n.sp. __ _----------------------------------------------------------------------------------------------------------322 18, 19. Views of the holotype (U.S.G.S. no. 761; U.S.N.M. no. 77009) from the Nacatoch sand near Kaufman, Kaufman County. 20. Back view of a paratype (U.S.N.M. no. 77010) from the same locality. The University of Texas Publlcatlon 4101 Plate 61 10 14 The University of Texas Publication No. 4101 PLATE 62 PACE Deussenia corbis, n.sp. _____________________________._________ -------------------------------------------------------------------------------------334 1, 2. Views of the holotype (U.S.G.S. coll. 14128; U.S.N.M. no. 77040) from the Kemp clay near a public road, 2 miles north-northwest of Deatsville, Travis County. Deussenia multilirae, n.sp. ----------------------·-----------------------------·---------------------------------------------------------------333 3, 4. Views of the holotype (U.S.G.S. coll. 764; U.S.N.M. no. 77038) from the Kemp clay near Deatsville, Travis County. 5. Back view of a young paratype ( U.S.N.M. no. 77039) from the same locality. Seminola? sp. ---------------------_______________________ -·_____ ----·-------------------------------------------------------------------------------· 330 6, 7. Views (x3) of a small specimen from the Neylandville marl on the Corsicana road, 2% miles north of Corbet, Navarro County. (U.S.G.S. coll. 16170; U.S.N.M. no. 77030.) Tryonia valida, n.sp. -------------------------------------------·---------------------------------------------------------------------------------------332 8, 9. Views of the holotype (U.S.G.S. coll. 763; U.S.N.M. no. 20890) from the Nacatoch sand near Corsicana, Navarro County. Busycon? sp. ____ ___ __ ____ .______.____________________________.. __ .. ___________ ------------------------------------------------------------------------324 10. A squeeze of an external mold of a specimen from the Nacatoch sand on the Stevens place, 1 4/5 miles northeast of Quinlan, Hunt County. (U.S.G.S. coll. 16162; U.S.N.M. no. 77070.) The Unlveralty of Texas Publlcatlon 4101 Plate 62 7 6 2 3 4 The University of Texas Publication No. 4101 PLATE 63 PACE Seminola crassa Wade ------------------------------------------------------------------------------------------------------------------------------329 1. Back view of a specimen from the Nacatoch sand near Chatfield, Navarro County. (U.S.G.S. coll. 762; U.S.N.M. no. 77029.) 2. Front view of a specimen from the same locality. 3, 4. Views of a young individual from the same locality. Deussenia travisana, n.sp. --------------------------------------------------------------------------------------------------------------------------333 5, 6. Views of the holotype (U.S.G.S. coll. 14126; U.S.N.M. no. 77037) from the Kemp clay in a public road, 1~~ miles north-northwest of Deatsville, Travis County. 7, 8. Views (xl 112) of a young specimen, a paratype (U.S.G.S. coll. 14128; U.S.N.M. no. 77035), from the Kemp clay near a public road, 2 miles north-northwest of Deatsville, Travis County. II ydro tri b ul us asper, n.sp. -----------------------------------------------------------------------------------------------------------------------330 9, 10. Views of the holotype (U.S.G.S. coll. 14139; U.S.N.M. no. 77032) from the Kemp clay in a branch % mile south of McLeod School, 6% miles southwest of Currie, Navarro County. The Unlveralty of Texas Publlcatlon 4101 Plate 63 The University of Texas Publication No. 4101 PLATE 64 PACE Be!Ufusus? coronatus, n.sp. __ ________ ____ __ __ ___ -----------------------------------------------------------------------------·--------338 I, 2. Views (xl1).d of the holotypc (Tex. Bu. 17300: U.S.N.M. no. 77055) from the Neylandville marl on the Corsicana road, 21;2 miles north of Corbet, Navarro County. 3. View (x4) of a young individual showing the characters of the apex,, from the same locality. (U.S.G.S. coll. 17.'365 ; U.S.N.M. no. 77056.) BelliJusus? sp. _______ _ __ ________________________ __ .. ____ _ __________________________ ----------------------------------------------------------------·····-341 4. View (x.)) of an inrnmplcte spef'imen from the Neylandville marl at the preceding locality. (U.S.G.S. f'oll. 17365; U.S.N.M. no. 77066.) Anomalofusus bellulus, n.sp. ______________________ __ __ ._ _________ _ ______-----------------------------___ --------------------------------335 5. Back view (x2) of the holotype (lJ.S.G.S. coll. 762; U.S.N.M. no. 77044) from the Nacatoch sand near Chatfield, Navarro County. 6, 7. Views (x2) cf a paratype (U.S.N.M. no. 77045) from the same locality. Aliofusus reaganz'., n.sp. ____ -------------------------------------_________ __------------------------------------------------------------------· 336 8, 9. Views (x2) of the holotype (U.S.G.S. coll. 761; U.S.N.M. no. 77050) from the Nacatoch sand near Kaufman, Kaufman County. Aliofusus reagani tumidus, n.var. ----------------------------------------------------------------------------------------------------------337 10. View (xl1h) of the holotype (U.S.G.S. coll. 761; U.S.N.M. no. 77052) from the Nacatoch sand near Kaufman, Kanfman County. ALinfusus reagani subti!is, n.var. -----------------------------------------------------------------------------------------------------------337 11. View (xl1;2) of the holotype (U.S.G.S. rnll. 761; U.S.N.M. no. 77051) from1 the Nacatoch sand near Kaufman. 12. Back view of the holotype enlarged (x2) to show details of sculpture. DeLLssenia ciboloensis, n.sp. ____________ --------------------------------------------------------------------------------------------------·-·----332 I.'3, 14. Views of the holotype (U.S.G.S. coll. 7721: U.S.N.M. no. 77036) from the Kemp day on Cibolo Creek, 11;2 miles west of Zuehl, in Bexar County. Fusus? robertsi, n.sp. ___._____ ____ __ _____ ______ ____ _ __ ____ ___________ _ __ ---------------------- --------------------------------------------------334 1.5, 16. Views (xl1h) of the holotype (U.S.G.S. coll. 14103: U.S.N.M. no. 77041) from the Nacatoch sand in a field, 3/5 mile west of Kaufman, Kaufman County. Plate 64 The University of Texas Publication 4101 The University of Texas Publication No. 4101 PLATE 65 PAGE R emcra dccora, n.sp. ______________ ·---------------·---------_. -------------------------------------------------------------------------------------345 1, 2. Views (x3) of the holotype rn.S.G.S. coll. 17.165: U.S.N.M. nc 77084) from the Neylandville marl on the Corsicana road, 21h miles north of Corbet, Navarro County. Reniera microstriata, n.sp. ________________________________ _ .__________________________-----------------------------------------------------------344 3,4. Views (x2) of the holotype (Tex. Bu. 17300; U.S.N.M. no. 77082) from the Neylandville marl at the preceding lornlity. Belli/usus? crassicostatus, n.sp. _______ __ __ ___ _____--·---------·----__ _________-----------------------------------------------------340 5, 6. Views of the holotype , Limestone County. (U.S.G.S. <'Oll. 138:~2; U.S.N.M. no. 77317.) The University of Tex a Public tlon 4101 Pl t 91 The University of Texas Publication No. 4101 PLATE 92 PAGE Placenticeras meeki Bohm 431 A large specimen (reduced as shown by scale in inches) from the Neylandville marl on the Dallas highway, 3 7 /10 miles west of Kaufman, Kaufman County. (U.S.G.S. coll. 17119; U.S.N.M. no. 77324.) The University of Texas Publlcatlon 4101 Plate 92 Scale in inches 2 3 4 5 6 7 8 9 10 11 12 0 The University of Texas Publication No. 4101 PLATE 93 ]>A(;E Sphenodiscus tirensis, n.sp. -------------------------·-----------------------------------------------------------------------_______... 435 1. Side view of a paratype (U.S.G.S. coll. 12930; lJ.S.N.l\L no. 77:-tn) from the Kemp clay on the G. W. Chapman farm, 11/~ miles southeast of Tira, Hopkins County. 2. Cross section at large end of the same specimen. 3. Cross section of inner volutions of the holotype (U.S.N.M. no. 77326) from the same locality. The University of Texa Public tlon 4101 Plate 93 The University of Texas Publication No. 4101 PLATE 94 PAGE Sphcnodiscus tirc11sis, n.sp. .. _____ __ ______ ____ ·-----______ ____---__ ____ -----------------_____----_ ___ ----·· ... _ ----------435 1. Holotype (U.S.N.l\L no. 12930; U.S.N.M. no. 77326) from the Kemp rlay on the G. W. Chupmnn farm, 1% miles southeast of Tira, Hopkins County. 2. View (x2) of inner sutures at a younp; stage in a fragment from the Kemp clay in a branch, 1/:.? miles sollth of McLeod School, 61h miles southwest of Currie, Navarro County. ( U.S.G.S. coll. 14139; U.S.N.M. no. 77329.) Placenticeras intercalare Meek (variety) _ __ --------------------------------------------------------------------·--------------------433 3, 4. Views of a specimen from the base of the Neylandville marl on the Dallas highway, 5 miles west of Kaufman, Kaufman County. (U.S.G.S. coll. 14102; U.S.N.M. no. 77325.) The University of Texas Publication No. 4101 PLATE 95 PAGE S phenodiscus pleurise pta (Conrad) ----------------------------------------------------------------------------------------------·--···--·· 436 1, 2. Views of a specimen from the Kemp clay on the G. W. Chapman farm, 11h miles southeast of Tira, Hopkins County. ( U.S.G.S. coll. 12930; U.S.N.M. no. 77330.) 3. Side view of a specimen from the same locality. 4. Side view (xl % ) of a specimen from the Kemp clay on the John A. Thompson estate, 4 miles northeast of Roane, Navarro County. ( U.S.G.S. coll. 12922; U.S.N.M. no. 77331.) B ele mnitella am e ricana (Morton ) ____________________ --------------------------------------------------------------------------------------437 5-7. Views of three incomplete guards from the Corsicana marl on the old Greenville road, 1 4/5 miles northeast of Quinlan, Hunt County. (U.S.G.S. coll. 11248; U.S.N.M. no. 77336.) 8. Cross section of the specimen shown in plate 6, which is split in half, revealing structural features. The Unlveralty of Tex a Publlcatlon 4101 Plate 95 INDEX Figures in blackface refer to pages where genera and species are described. Aachen district: 40 abbottii (Gyrodes): 281 Abdero1pira: 391 cbipolana: 391 aberran1 (Nostoceras): 21, 409-410, 594 Abe1inai group: 44 abrupt& (Anchura): 296, 297 aby11inu1 (Gyrodes): 45, 281 Academy of Natural Sciences of Philadelphia: 6 Acanthoscaphites: 426 acervulinoidea (Planoglobulina): 42 Aclr1a cerithlformis: 268 Acmaea : 256-257 occidentalis: 18, 30, 256-257, 528 Actaeon concinnus: 390 sabbana: 383 Acteon: 380-381 nitidu1: 38()-.381, 578 sub1triatus: 381 throckmortoni: 380, 578 Acteonina orientalis: 382 Actfnoceramus: 99 acuta (Cancellaria) : 363 (Caveola): 18, 19, 163-364, 574 acutata (Linter): 21. 85-86, 454 acutllineata texana (Lima): 145, 147, 480 acutimargo (Gyrodes): 284 acutirostris (Ostrea) : 11 O acutoco1tata (Sauvagesia): 188 acutodorsatus (lndoceras): 43 (Sphenodiscus): 43 acutula CEoancilla) : 28, 361-362, 572 Adams, H. and A. : 3 7 3 Henry: 243 adansonli (Pulvlnltes) : 161 adhaerens (BIradlolites) : 3 6 Adkins, W. S.: 5, 6, 71, 188 adkln1I (Nemodon): 82-83, 452 aequlco1tatus (Pecten): 136 aequlvalvl1 (Liopistha): 162 Africa: 35. 39. 42, 44. 45 AcaHll, M. M. L.: 63,. 68 Akera: 393-394 bullata: 393 constrict&: 393-394, 582 Alabama: 19, 22, 25, 26, 28, 29 alabamen1e (Cardium): 197. 201 (Granocardfum): 197. 201 alabamensi1 (ldonearca) : 9 4 Alberta: 35 Alblan: 34 Aldrich, T. H.: 318 Alcerfa: 42 Allofueus: 336-338 reaganl: 336-337, 562 1ubtfli1: 337, 562 tumidus: 337, 562 all11onensf1 (SphenodiHcus) : 435 Alpee-Maritimes: 40 alta (Cyprimeria): 25. 26, 212-214, 514, 516 (Paladmete): 367, 869, 576 alternata (Tuba) : 269 altlspira (Gyrodes) : 278 (Lunatia) = 278 alveata (Gyrodes) : 2 8 4 (Natlca): 284 Amauropsis: 278-279, 534 Jirata: 279 American Museum of Natural History: 6 amerlcana (Belemnitella): 30, 35, 39, 437-438, 624 (Gastrochaena) : 244 (01i&'OPtycha): 83, 390-391, 580 CProscala): 21. 267-2'68, 530 (Ro1tellaria) : 306 amerlcanus (Calliomphalus): 260. 261 (:Micraster) : 25, 26, 69-70, 448 (Plesiaster) : 25, 26, 69-70, 448 amica (Beretra): 376 (Nucula): 74 (Surcula): 876 (Turricula): 375 Ammonitea l'Ollevillensis: 418 Iewesien1is : 418 Jobatus: '34 1iva: 43 ampla (Ancilla) : 861 (Voluta): 861 amplificata (Pseudomalaxis): 257 (Weeksia): 257, 258 Amuletum: 369-372 hoylei: 370, 371, 576 curvocostatum: 370-371, 576 mcnairyensis: 370. ~71 venustum: 371, 576 Amuri Bluff: 45 Amusium: 137-138 danei: 137-138, 478 AnaklinoceraR: 414-415 reflexum: 18, 414-415, 600 Anatimya: 161-162 anteradiata texana: 161-162, 484 Anatina elliptica: 225 Anchura: 295-305, 548 abrupta: 295, 297 bexarensis: 297-298, 544 caddoensis: 302-303, 490, 546 campbelli: 303, 546 ciboloensis: 300, 305, 546 cooki: 301-302, 805, 546 elegans: 299-300, 546 hoggi: 303. 548 johnsoni: 302 lamari : 296-297, 544 lobata: 21, 40, 45, 298-299, 300, 546 media: 299. 300, 544 lynnensis: 301, 546 noackensis: 295-296, 544 pergracilis: 345 plenocosta: 299, 546 rostrata: 300 substriata: 296, 297 Ancilla ampla: 361 Ancyloceras: 422 Anderson, F. M.: 34 anfractolineata (Ringicula) : 389, 580 Angola: 44 Anisomyon: 395-397 borealis: 21, 23, 30, 33, 397, 582 haydeni: 21, 22, 30, 33, 396, 582 patelliformis: 30, 396 wieseri: 257, 396 annulifer (Hamites) : 398 (Solenoceras): 400, 401. 402 anomalocostata (Turricula) : 379 Anomalofusus: 335-336 bellulus: 335-336, 56Z substriatus: 336 Anomia: 147-151 ari:r:entaria: 148-151, 482 tellinoides: 17, 18, 19, 147-148, 150, 482 anteradiata (Anatimya): 161 texana: 161-162, 484 Anthonya: 182 cnltiformis: 182 Antillocaprina: 30, 37, 184 Antrim: 39 antrosa (Idonearca): 91 Aphrodina: 44, 208-211 navarroana: 21~211, 510 tippana: 208-210, 512, 514 Aporrhaia (Arrhoges) pelecyphora: 40 (Cultrigera) propinqua: 40 appre~sa R!'per (Haculites): 42 ( Hydrotribulus) : 330-331, 560 Astarte: 173. 174-175 crenalirata: 175 culehrensis: 174-175, 486 sukata: 173. 488 Astartemya: 173-174 fentressensis: 2~. 173-174, 488 At.a vus (Sc hizaster) : 6f) Atlantic Coastal Plain: 1~. 24. 2S. 2!"1. :rn. 3:~. 34, 3fi, 3!\, 41, 42. 4fi attenuata (PsC'udoliva): 372, 373 a11cella (Gryphaea): l lR Austin chalk: 21. 2fi, :n. :~ ·1 austinenRis (NC'ithl'a): 1:n (Peeten) : 1:l i nustini (Turritella): 291-292, 542 australis ( Dakoticanc<'r) : 17 H\"<'rillii (VolutodC'rma): 3fi7 Av('ry, vicinity of: 4R Axonoe<'ras: IR. 422-425 compr('sirnm: 422-423, 424. 612 multicostatum: 423-424, 612 rotundum: 424, 612 pilll!'\H': 423, 612 Raculites: :n. 402-407 arg<'nticus: 3 R asper: 42 earinntus: 407 claviformiR: 1~. 20, 21, 23. :rn. 33, 3~. 403-504, 588, 590 columnn: 2fi. 2fi, 405-406, 586 compr<'ssus: 404 grandis: :rn. 3:l, 404 ovatus : 4 0 .1 undat11s: 403, 405, 592 bail vi ( Dicroloma) : 4fi, 2!\~ (Perissoptera): 4fi, 2!l~ Raltic region: 3~ Baluchistan: 43 Banis: 279 siniform is: 279, 534 hl\rabini (lnoceramus): !l~ hnrhata (Serpula) : fi~ Barbatia saffordi: ~~ HarrPttia: 30, :rn. 37 limeston<': 2!\ monilifera: 3fi hartoni (Laternu]a): 161, 484 Bartsch. Paul: fi. 263 Hass<'. Elaine: 4!) Rasi;es-Alpes: 4 0 Bastrop County: 1 7 nautte. vicinity of: f) 3. !) 4 B<'lemnitella: 437-438 americana: 30. 3fi. 3!l. 437-438, 624 bulhosa: 30 lanceolata: 3f>. 41 mucronata: 3Fi. 3!"1. 40. 41. lOfi, t3R RC'lgium: :l~. 40 bC'llR (C~·mella): 1fi3. 1fi!) (Morea) : 327-328, 556 texana (CymE'lla): 21. :rn. 165-166, 486 (TornatellaC'a): ~~5. ~~6 lwlli (Gryphaea) : 25, 26, 2~. 1 lfi. 117-118, 470 Hellifus11s: 338-342 h11fTalot'nsis: 341. 564 coronat11s: 338-339, 562 crassicostnt11s: 340, ~41, 561 c11 r\" it•ostat11~ : ~ :rn. :H 1 rlcnts,·ill<'nsis: 340, 564 m11lticostnt11s: 340. 564 rPh11stus: 339, ~.10. 564 tcnuistriatus : 339-340, 564 Hdliscala: 268-269 crid<'ri: 269, 532 forsheyi: 21. 268-269, 532 rock<'nsis: 268, 532 tellisculpt11s (('amptonect<'R): 4fi. 1~2 (Pt.•cten): 4.'1. t:\2 belluluH ( Anomalofusus): 335-336, 562 (Calliomphalus): 40, 259-260, 528 Ben ArnoIcl. v fr in it ~· of : 4i Jh•n Hur, vicinity of: ·17 hrnhurenl'i!-. (Hemiastcr): 1~. 20, 67, 448 Publication No. 4101 B<'rdra: 375-378 n m it' ll : :\ i tl l'ontr1t1•ta: 376, 578 1·longata: 377-378, 578 lirmn: 375-376, :ii7, 578 orn11t11ln: 377, 578 ripl1•y1u111: :Vi f1 Htrinta: 376-377, 578 lwrryi ICymhophorn): 22, 232, 520 lh,xnr County: !l, lli. 17, :l7. llO, fit, ll2, 113 lwxarC'ns1• ( 14;pitonium) : 266, 21l7, 530 hl'xart•nsis ( Anchurn) : 297-298, 544 (Crassatt'lla): 178, 2fi4. 492 (Ndtht>a): 136-137, 478 ( l't•l'tt.'n) : 136-137, 478 lwxari (Ht.'mia-.ter): 24, 26, 4~. 65-67, 446, 448 biacuminatn ( Hemnita): 21. 379-380, 578 lln): 2R. 2!l. 2R7, 288-289, 11~~ Hilix (Solemya): 21, 2:l, :rn, :J:l, 71-72, 450 Hinekhorst, J. T.: 40 hinckhorsti (SphC'nodiHcus): ~!i. 40 hinodosa ( Eucyl'!os<"nln) : 261, 528 (Srnlaria) : 2fl 1 hinodosus (Troeh11H) : 261. 528 hilix (Solt.'myn): 21, 2:\, :rn, :\3, 71-72, 450 Hira1liolites: :rn. :\7 ndhat'l"C'llH: :\fi hi~hopi (TnmpHin): 2!l Hl11ek Bl11fT. dt'inity of: rl:l l~l11nford. H.F.: 4:\ B1~ggiltl. 0. B.: 1flfi Hiihm.•I.: 40 Holi\'inn inernsHntn: 42 Boltt'n.•I. F.: I :Vi hort•:dis (Anisomyon): 21. 2:\, :rn, :\:\, 397, 582 Hornholm: ·11 Hiis1•. Emilio: :rn. 12fl HourJ'!'l1t'tiel"inida1': 61-62 ho11rn<'i ( Notosc<'l<'s) : 17 Hournonia: :rn. :n HoWl'll. N('JI L.: 6. howC'nae (Canlium): 22. 198-199, 502 (Granoeardium) : 22. 198-199, 502 Htl\vit' County: !l. 10. 4~. 4!l. flO howiei ( Nemodon): 81-82, 452 hnwicnsi" (SC'rJHiln): 58, 4t2 Hoyle. ('. B.: fi hoylei (Amuletum): 370, 371. 576 nramlettP. w. A.: () Brazil: 3~ hrazilit'nsis (Sph<'nociiRcus): ~~ hrf'\'P ( Liopep]um) : 351, 568 Hreviarl"a: 86-89 haddon fiellemnit<'llR): 30 f lsol"ardia): 206-207, 508 Hulin <'oncinna: :rnt-3!l2 c\'lindract•a: :rn4 n~ortoni: 3!ll, 3!12 hullata (AkC'ra): 39;~ Hullina ( Ab: 36 coraloidea (Caprinella): 184. 186 cnr-anguinum. ( Micrast<'r): ;~4 (Spatangus): 68 Corbet, vicinity of: 47 corhetensis ( Drepanochilus) : 307-308, 30!"1, 548 (Nuculana): 77-78, 450 corhis ( D<>ussenia) : 334, 558 Corhula: 234-240 crnssiplica: 42, 234-235, 236, 522 navarroana: 236 inflata: 239-240, 522 Jinteroidea: 238-239, 522 paracrassa: 4 2 perhrevis : 2 3 6 rockensis: 237, 239, 490, 522 subradiata: 238, 23!"1 texana: 237-238, 23!"1, 522 torta : ?36-237, 522 wiIliard i : 2 1• 235-236, 2:n. 522 woodi : 239, 522 corhuliformi!'I (Paladmd<'): 366. 367, 3fi!l, 490, 576 corn11tus au, ,J.: 4 !) Cottr<'a•1. M. G.: fl!) CO\'E>nsis (Lima) : 14 2 Cox, L. R. : fl~. 1 !lfi Cranlla: 4!l . 176-180 hexarensis: 178, 2!l4, 492 cedarE>nsis: 178-179, 488 chatfieldensis: 178. 492 manorensis: 177-178, 492 pteropsis: 176. 179 011inlanensis: 1i6, 179, 488, 490 ripleyana: 177 yadMa: 4!'l. 171), 178. lRO bexar~nsis: 178, 254, 492 elm t fit'ldensis: 178, 492 manort•nsis: 177-178, 492 WHril111t11) : 352-353, :Hd, 568 lo1wn ( llrillutn) : 353 crnssil'ost11t11s (B<'llifusus): 340, !\·11, 564 ( l'u).!1\t'llus) : 4:\ Crassi1wlln: 1~;\ erassiplicn (Corhuln) : 4 2. 234-235, 2:rn, 522 na\'arronna (Corbula): 2:rn cras~um (Nostol'C'ras): 411. 412, 596 (Pt ~·c h1wt'ras) : :rnn (Solt'llt-262, 528 crt'trnlirata (Astarte): 17fi (Vt't<'rirnrdia): 17fi crennta (Gyrodt's): 27!1, 280 (Natica): 27!l C rt'tll'Ila : 153-155 t'k~rnn tula: 1fi4-1 5fi sc~il'n: 24. 26. 2!l, 153-154, 484 Creonella: 263-265 ci<'llS~H'lli: 265, 530 triplicata: 1H. 21. 263, 264-265, 490, 530 whitt>i: 263-264, 265, 530 cretacpa appressn (Tornnt<>llnea): 3R!l, 386, 580 ( I:ullopsis) : :rn:l (Cliona) : fii) ( Diplo-llS correlntion chart: 7 Cr<'tac<'o11s-T1'rtinry uneonformity: :i2 erl'tac<'llm (Busyron): 324 ( l'rotohusycon): :{24 cn,tn1·ica (Clionn): rir) crilwlli ( Lin<'nrin): 223, 518 Crickmn:v. C. H.: 127 cridt>ri ( Jh,lliscnln) : 269, 532 Crim<.>an region: 41 Criocnrdi11m du mos um: I !l6. 1 fl7. 201 Criras: 422 CruciJ.r<'ra formo!rn: 61 <'ru~taceans: 15 Crvs ta) Lake, vicinity of: 4 8 C11.ha: 2\l, 37 C11culla<'a cnpax: R9, 90 tippanR: R!l, !l2, 93, !H v11lgaris: 90, !)~ wai!C'i: \12, n:l c11llwrsoni (Rinl{k11ln) : 388-389, 580 <'till'hr1'nsis (A~t.nrt<>): 174-175, 486 cultriformis ( Anthonyn): 1~2 ('11ltri~Pr11 propinq1111: ·10 c·11neiformi~ ((~11i-;trorhaPn11): 2•\2. 211 r111wifrons (N11c11la): 7·1 C111wol11s: 156-158 tippnna: 2fi. 157-158, 481 C11rri1'. vicinity of: ri:\ n1rt11s (Cardinskr): f.3 1·11nat11s (Camptont'ct<.>~): 132 ( P<•cten) : 1 :l2 c11n·icostatus ( H<>llifus11s) : :~:Hl, :~41 (Odontofusus): :l:l~ cun·irostris (Ostn'n): 110 c11n·oco-:tat11m (Am 11h't um) : 370-371, 576 C11Hhman. JoHPPh A.: 2:~ Cuspidaria: 166-168 grann. 167 morea1wnsis: 167 Yf'ntrico~a: 167 c11thnnd<'n~is (Cap11)11s): 22, 274, 275, 534 C11\'ier. G.: 63, 242 ct1\'i1•ri (lnocC'ram11s): 98 Cvclorisma: 217, 218-219 . pumila: 218-219, 512 Cvlichna: 394-395 . incisa: 395, 582 reda: 395 secalina: 21. 394-395, 582 striatella: ~!ll cvlin-117, 468 veaicularia: U, 48, 116, 118 vc:>mer: 106 Gryphaeostrea: 11&-120 canalieulata: 119 vomer: 18, 81, 89, 106, 118-120, 470 Guadalupe County: 14, 15, 16, 24, 49, 50, 52, 54 suadalupen1e (Brevicardium) : 205-208, 504 suadalupen1ia (Lima): 144, 480 Guarlco, State of: 8 7 Guaeare formation: 87 Guatemala: 80, 86, 37 Gulf Coastal Plain: 18, 24, 25, 30, 33, 34, 35, 39, 41, 42, 46 Gulf realon, eastern: 24, 25, 28, 29 Gllmbellna: 87 GOmbelltria: 37 Gyrodea : 279-284 abbottii: 281 aby11inus: 46, 281 acutimareo: 284 altlapira: 2 7 8 alveata: 284 crenata: 279, 280 major: 280, 281 obtu1ivolva: 278 petroaua : 282-283, 538 rotundus: 26, 281-282, 538 1pillmani: 283, 284, 538 1ubcarinatus: 25, 282, 283-284, 538 1upraplicatus: SO, 280-281, 538 tenellus: 4 5 Gyroidina : 4 2 Habana formation: 29 haddonfteldenais (Breviarea) : 86, 8 7 Hadyzhenaky re1ion: 41 Haiti: 87 hakobutenais (Yoldia): 44 Hakobutl sandstone: 44 Han, James: 133, 184, 253, 404 halli (Pecten) : 183, 135 (Pollnicea) : 2 7 6 (Syncyclonema) : 135 Haminea: 394 cyllndrica: 891, 892 hydati1: 892 minor: 892 occidentalis: 392 9'mp1onen1la : 394, 582 1ubcyllndriea: 892 Hamitea: 402 annullfer: 898 hamula (Glycymeris): 85 Hamulu1: 24, 58-81 huntenafs: 20, 61, 442 onyx: 58-60, 442 1quamo1us: 28, 6o-61, 442 walkerenafa: 61 Hanover Province: 40 Haplovoluta: 321 Harbison, Anne: 6 Barpaso tippana: 809 Haus, Emile: 89 haushtonf (Palaeomorea) : 45 Haute-Garonne: 40 Haute1-Alpe1: 40 Hayden, F. V.: 896 haydenl (Anlaomyon): 21, 22, 30, SS, 398, 582 Bawkin1, H. L. : 86, 8 7 Hebert, M.: 41 hebes (Tornatellaea): 388, 580 Hedberg, H. D.: 87, 38 Heinz, Rudolf: 99 Helcion nechayi: 27 4 patelliformis: 396 helieinum crassum (Nostocerns) : 411, 412, 596 humile (Nostoeeras): 412, 596 (Nostoceras): 21, 4lo-411, 412, 594 helicinus (Turrilites) : 412 Helic:>coceras: 417-418 navarroense: 18, 21, 417-418, 600 Hemiaster: 28, 83-87 benhurensis: 18, 20, 67, 448 bexari: 24, 26, 43, 65-67, 446 448 dalli : 83-65, 446 ' delawarensis: 67 gauthieri: 67 (Inte1raster) slocumi: 66 lacunosus: 66, 67 madagasearensis: 45 maestriehtensis: 67 oldhami: 43 sloeumi: 24, 26, 45, 66 Hemipneustes striato-radiatus: 40 Hemiptyehoeeras: 399 Henbest, Lloyd G.: 6 hendersoni (lsoeardia): 206, 207, 508 Hennig, A.: 110 Hercorhyncus: 321-324 coronale : 323, 556 malleiforme: 321-322, 323, 556 mundum: 322-323, 556 nodosum: 322, 823, 556 tennesseense: 321 tippanum: 321 vadosum: 821, 322, 558 Herrmannsen, A. N.: 394 Heteroceras emerichi: 414 Hetonai group: 4 4 hetonniensis (Cymbophora): 44 (Spisula): 44 hilgardi oecidentalis (Micrabacia) : 14 Hill, Robert T.: 7, 188 hillana (Protoeardia) : 2 0 4 hilli (Sauvagesia): 187-188, 500, 502, 504, 506 Hindesastraea diseoidea: 15 Hippocampoides : 259, 528 hippoerepis (Scaphites): 34 Hippuritella syriaca: 43 Hippurites: 184 (Hippuritella) syriaca: 43 hoggf (Anehura): 303, 548 Hokkaido: 44 Holland: 38, 40 Holland, T. H.: 43 Holzapfel, Eduard: 214, 261, 275, 284, 298, 357 Homomya: 159 thrasheri: 158, 484 Hopkins County: 10, 27, 48, 49, 53 houstoni (Nuculana): 77, 450 (Turritella) : 292, 542 Howell, B. F.: 6 hubbardi (Lutema): 373-374, 576 humile (Nostoceras) : 412, 596 Hunt County: 9, 11, 14, 17, 23, 27, 46, 47, 48, 49, 50, 51, 52, 53, 54 huntanum (Cardium) : 202-203, 490, 506 (Trachyeardium) : 202-203, 490, 506 huntensis (Hamulus): 20, 61, 442 Hyatt, Alpheus: 40, 44, 343, 397, 400, 407 hyatti (Nostoceras): 410, 596 hydatis (Haminea) : 892 Hypotrema: 151 Hydrotribulus: 330-331, 332 asper: 330-331, 560 nodosus: 831 Iehthyosareolites: 184 eornutus: 184 Idonearea: 89-96 alabamensis: 94 antrosa: 91 capax: 25, 26, 92-94, 95, 456, 458 deatsvillensis: 94-95, 446 kingsensis: 91-92, 454 m urrayi : 95, 458 powerai: 90-91, 92, 454 vulgaris: 89 Imerites : 414 inaequalis (Paladmete): 388, 576 incisa (Cyliehna): 395, 582 inerassata (Bolivina) : 42 incurva (Ostrea) : 39, 110 The Uufrcrsity of Tc.ms Publication No. 4101 index map: ~ India: 4:{, 1:2:{ Indoeeras acutndorsatus: .1:l in fla ta (Corbula) : 239-240, 522 (Cymlwphora): 232-233, ~:i.1. 520 (Liopistha): llil Inoceramus: 98-101 barahini: !l~ beds: 4·1 eu\'ieri: !l~ divt>rsus: :l.t involutus: \t~ proximw;: !l!I rt>gularis: 4:2, 4·1, .1;, schmidti: ;{.1 undulatoplicat us: :l.l vanuxemi: I~. :21, :lO, :l:l, ·1:2, ·lf1, 90-100, 101, 460 inornatum ( Dt.1 ntalium): 2f1·l insignis ( Linthia): li7 insolita (Limn) : 2 li, l ·l li intercalar<> (Plaeentin1 ras) : 1~. :lO, 433-434, 62:l Integrastl>r: li7 slocumi: 6li intcrrupta (Strt.1 p::;idura): :l:Hi invag-inata ( Dalliconcha) : !lli in\'olutus ( lnoeernmus) : !l~ lrt.1 dalt.>, Tom: 24·1 Irt.•land: :rn irelandi ( lsocardia) : 207, 508 irregularis (TPredo): 247 Isocardia: 206-208 bulbosa: 206-207, 508 (Cardium) : 202 diffwoodt>nsis: 20li, 207 ht.•ndersoni: :20ti, 207, 508 irelandi: 207, 508 shumardi: 207-208, 508 tintonensis: 20~ truneata: 20~ Jamaica: 2!l, :rn. :l7 Japan: 44 ja\'ana (Murt>x): :Vi:l krseyensis (Cuspidaria): lliti, lli7 Johnson, C. W . : ~ 1 . 2:i 2 , 2li l , 2 7 0 , :l :l ~. :l 4 4 johnsoni (A nc hura) : :rn2 Jones. J. H . : 2 4 :l jonPsi (Turritella) : 290-291, 540 jouanneti (Laiwirousia) : 4:l jsmai.'li ( Libycoeeras) : 4 2 Kadonosawa formation: ·14 kaffraria (Can111tont>ctt.'s): 4:i (Peden) : ·l :i Kane, William G.: :lf1 Karahuto: 4.1 Kaufman County: 12, lfi, 17, ·lti, ·17 ..\'(, ·l!l, fill, !) 1 vicinity of: 4C, ·17, ·lK, •l\l, fill ka u fma 1wnsis (('am pto1wd('S) : 133, 476 ( Clycynwris) : 84-85, 452 ( l't.•1·t t.'11) : 133, 476 Kau11l:ow1•n, F.: ·l O Kl'llt>r, Alt.,xandr.·: .\:l KPllt·r, H. M.: 11 Kemp 1· lay : f1, 7. !t, 1"' ~I . 2 :l, 2 l. 2 .-, :: l. :L~. :\:I, :l f1, :l 7 ana!ysis of fa1llla of: ~'( corr~·lat ion of: ~ !l dt•fi nit ion of: 2 7 fossil,; from: ;,2 :d Kii: ·1·1 Killian, W.: ;\'( Kimhro. \'i(·inity of: r.ti. fi:!. ;,.1 kimhro!•nsis (1.ima): 145-146, 480 Kin<"aid formati11n: ;{:! kin~Yj (i'Pdt'!l): 135, 474 (S~·nn·1·l1111t'ma \ : 135, 474 Kin~~s ('rt't.•k \'allp~·. \'i!·inity of: ·17. -1-< kin~!S('nsis nudiscus): :l:i Kiipinge: 4 1 Kossmat. Franz: 4:l Kotkh formation: 41. 42 Krt.•n k ('I. Erie h : 4 ~ Krumbt.>ck. L.: 4~ kiimnwli (Cardium): l!lH, l~Hl ((;ranocardium): l\lH, l!l!l (T11r1111s): :!·l7, :!4!1 Kt1111m,•lia: :!·l·l l\.11z.11h11tn s1111dstonl' nnd 1·onglon1t.•ratt1 : •l·l lact.'rtosn ((;Jyn·m,•riH): ~r, lact1nosus (llt1 mi11stpr): lili, Iii (Sp11t11ng11s) : lif1 )ap\·igata ( E11lim11): 21if1 Lamarck, .J. IL: 2·l:l lamari (Anchura): 296-297, 544 Lamht•rt. M. J.: :n. li:{. lif1, lili, lii, liH Lanct.• formation: lH, 21, :rn lanceolata ( Ht'lt•mnitt>lla) : :l:i, 41 lanceolatus ( Mytilus) : 156 LandC's: 40 lanl{tlida (Mort.1 a): 328, 556 lnnhami (Pyropsis): 315-316, 552 Lapeirousia: :rn. :n j o u a n n eti : 4 :l syriaca: 4:{ l:qii~losa ( Delphinula) : 25H Lara, State of: ;{ i larva (Ostn1a): 112 Laternula: 159-161 bartoni: 161-484 robusta: 4 4. 160-161, 484 suble\'is: 160, 484 sulcatina: 21, 159-160, 484 Lawrt.>nl'l', \'icinitv of: -l 7 Leda protc1 xta: 7~l l,pgunwn: 215-216 apprt.1 ssum: 21fi eoIH't.•ntricum: 21 fi, 21 G t.•llipticum: 215-216, 518 planulatum: 2lli leioderma brevt> ( Lio1w11!11m): 351, 568 (Liopeplum): :l51, :H12 longum (Liopeplum): 350, :lfil, 568 tahulat um ( Lio1wplum): 22. 351, 352, 568 ll'nolensis ( Pyropsis) : :n !I kns ( l't.1 cll'n) : 1:l1 lenticulare ( Placentict.'ras): .t:l4 (Sphl'ntHliscus): :rn. 4:l4, 4:lf1 Leon Cr1..1 t.1 k vallt1 y, vicinity of: G:\ leonensis (Cardiaster): 62-63, 444, 446 leoni (Turritella) : 291, 540 leprosa ( Xenophora) : 284-286, 538 Leptosolt.•n: 226-229 billlicatus: 226-228, 520 elongata: 22H levis: 228-229, 520 ling-uliformis: 228, 520 quadrilatt'rus: 228, 520 lt•\'t' ( nC'ntalium) : :rn. 253-254, 526 ),•vi..; ( Lt>ptosoh1 n): 228-229, 520 ( l'it'Slo<'hiJUH): 350, 568 L1•wt'": :l!l h'wt.•si1•nsis ( Ammonitc•H): ·11 K Ll'wis Fl•rry, vicinity of: ·IK I .t'\'lllt'riastl'I': ti7 l.il~van Dl'Sl'l't: ·12 I.ih)·co1•t'ras .ism:tt'li: ·I :l li,...:nari11-; (Scaphandl'I'): :l!ll Lima: 142-147 a1·11tilin1•ata tt•xa11:1: 145. 1·17, 480 ('Okt•i: 143-144, 14j, 482 tlt•:itsvilltonsis: 143, 1·1·1, 1·17, 480 ('O l\t•i : 1 ,, 7 l!l'ronimot•nsis: 1 ·12, 1 ·l:~. 144, 480 ~~t1adal11pt.•nsis: 144, 480 in s o Iit n : 2 G • 1·111 kimhrot•nsis: 145-146, 480 ( ()st l't.'H ) : l ·1 2 o:xyplt.•ura: 142 pi>la)liea: 1·12 t' o v C' nsis : 14 2 \\'oolst•yi: 142-143, J.lfi, 1-ti, 480 l'l'lic11lata: 14i sa~·rc.>i: 146-147, 480 sPllar1lsi: 142, 14·1, 482 sq ua rosa : 1 4:l tt'xnna: 145, 147, 480 woo)seyi: 142-143, 14G, l·ti, 480 limhata (Rt.'ussia): 42 Limbourg, Holland: 40 Limestone County: 18, 1 i. 27, 4i, GO, 5:~. 54 Limonsis: fl6 meeki: 21, 96, 454 Linearia: 221-224, 516 earolinensis: 45, 224 eribelli: 223, 518 (Lucina) : 190-191, 500 Index 633 metaatriata: 221, 222, 228, 22' navarroana: 223-224, 518 pectlnia: 222-223, 514 wleaerae: 222, 224, 514 lineata (Serpula) : 28, 57-58, 442 (Venlella): 21, 170-171, 486 lineatua (Nemodon): 83-84, 452 Uneolatus (Solyma) : 2 2 5 linl'ua (Litbophaga): 156 linguaeformis (Pteria): 21, 23, 30, 102-103, 458 Llngula: 21, 70 subspatulata: 21, 28, 30, 70, 440 llnguiformis (Gastrochaena): 246 linl'uliformis (Leptosolen) : 228, 520 Llnn6, C.: 242 Untea (Cymbophora): 231 Linter acutata: 21, 8&-86, 454 llnteroldea (Corbula) : 238-239, 522 Llnthla: 28, 67-68 lnsienla : 6 7 variabllia: 24, 25, 26, 88, 450 Liopeplum : 350-352 breve: 351, 588 canalia: 362 leioderma: 851, 352 breve: 351, 588 longum : 350, 851, 568 tabulatum: 22, 351-352, 568 Liopiatha: 182-164 aequivalvia: 162 formosa: 21, 164, 488 lnftata: lU protexta : '3, 182-184, 486 Liothyria: 22' Liotia macroatoma: 261 Lirata (Amauropsis): 279 Liroaoma cretacea : 8 4 8 Ll1podeathe1 achlotheimi: 298 Littfg, vicinity of: 5 2 Jtttlel (Perviaonota) : 7 9 (Pholadomya): 21, 158-159, 468 Lithophaga: 155-158 carolinenais: 80, 155-156, 478 lingua: 166 rlpleyana: 156, 156 lobata (Anchura): 21, 40, 45, 298-299, 300, 546 media (Anchura): 299, 800, 544 lobatua allfsonensis (Sphenodiscus): 435 (Ammonites): 434 (Sphenodiscus): 26, 435 Lockhart, viclnitv of: 53, 54 Lomfroaa: 348-350 cretacea : 21, 34&-349, 568 Londonderrv : 3 9 Joni'& (Drilluta) : 353 Longchaeus mazatlantica: 263 longi (Turritella): 291, 540 longifrons (Nuculana): 44, 78, 450 Lon1oconcha: 357-359 dalll : 359, 574 navarroenais : 21, 357, 572 lonaum (Liopeplum): 350, 351, 568 Loriol, P.: 67 Lov•n. S.: 394 lubbocki (Weeksia): 258, 528 Lublin-Lemberger: 41 lucerna (Cardium) : 48 Lucina: 189-192 chatfteldana: 191, 502 elebula: 190 linearia: 190-191, 500 mattiformia: 190, 490, 500 oleodorsum: 192, 502 parva: 191 P&rvilineata: 18, 189, 500 pfnguis: 217 ripleyana : 191 seminalis : 191-192, 502 lunata (Ostrea): 89, 119 Lunatla altfspira : 2 7 8 Lf1neburg: 40 Lupira: ~1 majcr: 861 pyriformis: 36C>-361, 572 variabilia: 361, 572 lusitanicus (Sphaerulites) : 187 Lutema: 37s-375 aeniculata: 374-375, 576 hubbardl: 373"-374, 578 munda: 374, 578 almpaonenRfa: 373, 874, 578 L:vcettla: 167 bnnen1l1 (Anchura) : 301, 546 Mac Gilavry, Henry James: 36, 87, 184 MacNeil, F. Stearns: 6, 80, 81, 85 macrostoma (Liotia): 261 Madagascar: 45 madagascarensis (Hemiaster) : 45 Maestricht, Holland: 40 maestrichtensis (Hemiaster): 67 (Micraster) : 70 Maestrichtian: 34, 35, 36, 37, 38, 39, 40, 42, 43, 44, 45, 46 Magdalena Valley: 88 Maiz, Mexico: 20 major (Cyprimeria): 26, 218 (Gyrodes): 280, 281 (Lupira): 361 malleiforme (Hercorhyncus) : 321-322, 323, 556 Malmo: 41 Manor, vicinity of: 50, 58, 54 manorensis (Crassatella): 177-178, 492 (Steriphonotrochus) : 15 Mansfield, W. C.: 6 manzaneti (Tuba) : 269-270, 530 Maracaibo Basin: 37 marocosense (Brevicardium): 206, 504 marcosensis (Tellina) : 220, 516 Margaritella: 272 ftexistriata: 272 pumila: 272, 582 Mari Hills: 43 marine equivalents of Navarro: 83-46 Marion, vicinity of: 50, 52 Marlbrook marl: 19 Maliere, Rene: 4o Marsupites testudinarius: 34 Martindale, vicinity of: 49 martindalensis (Nemodon): 83, 452 martini (Drepanochilus) : 306-307, 309, 548 Maryland: 19, 22, 25, 26, 31 marylandica bella (Morea): 327-328, 556 (Cardiaster): 63 languida (Morea) : 328, 556 Mataxa: 36~366 elegans: 365 s ubteres : 366, 574 valida: 365-366, 574 multilira: 366, 574 Matheron, M. Philippe: 125 Mathilda: 270-271 cedarensis: 270-271, 530 ripleyana : 2 7 0 matsoni (Cancellaria) : 362-363, 572 mattiformis (Lucina): 190, 490, 500 Maury, Carlotta: 38 Maverick County: 9, 17, 27, 41 maxeyi (Ornopsis): 343, 566 maximum (Pecten): 130 mazatlantica (Longchaeus) : 2 6 3 (Pyramidella) : 263 McClanahan, vicinity of: 46, 49 McLeod School, vicinity of: 53 McNairy sand member: 22 n1cnairyensis (Amuletum) : 370, 371 (Turricula) : 369 (Turritella) : 292 McQueeney, vicinity of: 49, 50, 52 media (Anchura): 299, 300, 544 Medina County: 16, 23, 24, 35, 50, 51, 62 Medio Creek valley, vicinity of: 51 Medionapus: 316-318 elongatus: 316, 317, 318, 554 Mediterranean basin: 39 region: 33, 35 sea: 45 Meek, F. B.: 98, 133, 162, 155, 163, 167, 184, 203, 211, 247, 249, 253, 254, 272, 273, 305, 309, 350, 390, 392, 395, 396, 899, 400, 404, 426, 427, 434, 435 meekanum (Solenoceras) : 400 meeki (Limopsis): 21, 96, 454 (Placenticeras): 17, 18, 30, 33, 431-433, 616, 618 Mendez shale: 29, 35, 36, 37, 40, 41 Meretrix eufaulensis: 210 mesenterica (Ostrea): 112, 113-114, 466 Mesocrinus: 25, 26, 62 Mesorhytis obscura: 346 Metaptychoceras: 399 metastriata (Linearia): 221, 222, 223, 224 Mexico: 20, 23, 29, 30, 35, 36, 37, 40 Miakura beds: 44 Micrabacia hilgardi occidentalis: 14 mineolensis: 14 navarroensis: 15, 270 The Uni11crsity of Te.rns Puhlication No..4101 Micrn~ter: 68-70 americanus: 2fi, 26, 69-70, 448 cor-anguinum, zone of: ;q maestrichtensis: 70 peinei: 6~ (Plesiaster) amerkanus: 2fi. 21i. 69-70, 448 microcancelli (Calliomphalus) : 4 0. 260-261, 528 microstriatu (Nucula): 22, 74, 450 (Remera) : 344-345, 564 microstriatus (Capulus) : 275, 2 7 Ii, 534 microtuberum (Cliona): 2·l, 2~. 54-56, 440, 444 Midway group: 2~. ;{ 1, :~2. :J:{ Milam County: 14. 17. 20, -1ti, 47, fill, ;d mineuh•nsis (Micrabacia): l·l minor (Hamint.•a) : ;{!12 ( Plt•urotoma) : :no MiraiH·apha eoslntus: 3!11 Mi~:er, H. D.: 2f1ti Mississippi: 1 !I, 22, 24, 2fi, 21i, 2!1, :~4. ;{~1 missi~siµµiensis ( Pel'tt>n): 138-139, 478 (Radiopt.•ctt•n): 138-139, 478 MitoJuan formation: :n. 3~ Mcberg, J. C.: 41 modiolus ( Mytilus) : 152 Monagas, State of: :J 7 monilif<.~ra ( Harrdtia) : ati Monmouth formation: l!I, 22, 2!"1, 2ti monmouthensis (l'ano\w): 2 ·11, 2.12 ( Pseudonwlanin) : 2tifi (Pyrifusus): :~:Hi Monodonta: 262-263 cancellosa: 262-263, 528 Mons Basin: 40 Moore's crossing, vicinity of : fi2 nwort.•i (Trigonia): 129-130, 474 Morea: 326-328 beIla: 327-328, 556 cancellariu: :J2ti, :{27, 328 corsicarwnsis: 326-327, 556 crassa: 327, 556 marylantlica bt>lla: 327-328, 556 languida: 328, 556 reticulata: :{27 moreauer1sis (Cuspidariu) : l li 7 Morocco: 4 2 Morton, S. G.: Ii. fi~. ~!I, Dl, \1:~. !I~. 112. l lti, 176, 2 1 1 , 2 ti 6 , :~ !I ~ mortoni (HuIla): :~!ll, ;{!12 (Cyµrnea): 314 (Ostr~a): 105 (Solenocera::1): 30, 400 Mortoniceras: 4 4 delawuren::1e: 45 strungeri: 4fi texanum: :{4 Mount Laurt>l sand: 1!I, 2;{ mureonata (Helt•mnitella): :~ri, :rn. 40. 41, 10;>, 4:{~ Muellerried, F. K. G.: :rn Muir, John M.: :{Ii, 41 MUiler, Joseph: 15li 0. F.: 24:J, ;{\1:3 mullicaensis (Plil'atula): 2!">, 2(i, 140-141, 478 mulliensis (Vt.•niellu): 171 multicostata ( Gra11hitlula): 347, 566 multicostatum ( Axonoct•ras) : 423-424, 612 rotundum (Axunol'eras): 424, 612 (Solenoeeras) : 402, 586 multicostatus ( Bellifus11s): 340, 564 multilira ( Mutaxa) : 366, 574 multilirae ( Dt.>ussenia) : 333-334, 558 multiliratum ( Doliopsis): :~ 1!I (Dolium): :~l!I mumia (Fistulana): 244 (Gastroehat•rnd: 242, 24:{, 24 -1 munda ( Lult•ma) : 374, 576 (Tellina): 219, 220, 221, 490, 518 mundum ( Hercorhpwus) : 322-323, 556 Munier-Chalnws, M.: l liH munitus (Spondylus): 139-140, 482 MiinHter, Gt'or~e Graf Zu: 21i 1 mutnbilis (Gryphat,a): 24, 0, 115-117, 468 ( PaleopHephaea) : 4!l (Voluton10rpha): 3fiti Murex javana: :Vi3 m urrayi (Idonenrca) : 95, 458 Mysia gibbosa: 21 7 paralis: 216 Mytilus laneeolatus: l !"16 modiolus: 15~ polymorphuH: l 5G tegullatus: 156 Nacatoch sand: r;, H. lH, 24, 25, 2C. 27. 2~. :itl analysis of fauna uf: 20-22 correlntion of: 22 definition of: 20 frn~sils from: 47-49 llH<'Htllus): 310-312, 550 Nndn sand,..torw: 4 4 Nngno, T.: 4 4 Napulus: 318-321, 552 oetoliratus: 2~. ill !I, 320, 554 tubl:'l'l'ttlatus: 319, :{20, 554 whitfieldi: ;{ l ~l nasuta (Ostrt•a) : 112 Natal: 44 Natica (Gyrodt•s) nlvt•ntn: 2~4 crennta: 27!1 Nautilus dt'knyi: ;{!l7 Nnv11rro dimntt•: :{2 ('o u n t y : 1 1 . 12. 1 :I, 14. 1 fi, 17. 2 4. 2 H, 4 li, 4 7, 48, 4!1, fill, fil, fi2, f1:1. f>4 R"roup: :lH analysis of fnunn of: :Hl-:!:~ elassificntion of: ti fossil loealiti<.•s in: 46-54 ~·t•Jlt'ral featurt.•s of: ~ historv of name of: fi, 7 mnps, · Bowie, Red River, Franklin, Hopkin::1, Delta counties: 10 Guadalupe, lh-:xnr, Mt•tlina counties: 1li Hunt, Collin, Horkwnll countit•s: 11 Milam and Williamson t•ountit>s: 1 ·l Nn varro, Linwst.one, Fulls 1·011ntit•s: 1~ Travis, Cnltlw1•ll, n11adnl111w 1•11u11ti1•s: 1 fi maritw t>q11ivnlt•nls of: ;{:~-,1ti subdivisions of: !I na vnrron nu (A phrodinn) : 210-211, 510 (Corbuln): 2:rn ( Linenria): 223-224, 518 na vnrroan us ( Nemudon) : 81, 452 H11varr1wnse (llt•Jiol'eras): 1~. 21, 417-418, 600 na varroensis ( Longol'onl'ha) : 21, 357-359, 572 (Micrahnl'ia): lfi, 270 (Volutilitht•s): :H17 (Volutodt•rma): 21, 357-359, 572 nuvarroi ( Dentalium) : 253, 526 Navesink marl: 2:L 21i nt>chavi (Fissun•Jla): 274 (Helcion): 274 Nt•ithea: 136-137 austinensis: 1:Vi bt' Xart>nsis: 136-137, 478 <'aStt.>eJi: 40 q11inquecostutus: :rn Nemocardium: 20:l Nl'modon: 81-84 adkinsi: 82-83, 452 howiei: 81-82, 452 conradi: Ht t.•nfnulensis: Hl, H:L H·l, 490 lineatus: 83-84, 452 grandis: ~1 navarroanus: 81, 452 rnarlindalt•nsis: 83, 452 stantoni: H1 lll'Ub<.>rgil'us ( Paraparhydisl'us): :{G, 40 rwust•ns<' (Unintrdium): 1!13 New Jt.'rst>y: 1!l. 2:1, 2ti, :n Statl' Museum: ti N PW Zt.'nlnnd : 4fi Neylandville marl: Ci, 9, 20, 21, 22, 24, 2f>, 26, 27, . 2~. ;{:J, :{fi analy:,;is of fnunn of: 17-19 l'orrelation of: 1 9 detlnition of: 17 fossils from: 4ti-4 7 Neylundville, vil'inity of: 47 nkaisei (Racliolites): 1H7 n il'olleti (Discoscaphitt>s) : 4 2 ~l. 4:rn Nilsson, S.: 110 Niobrara limestorw: 30 nitidus (Aeteon) : 380--381, 578 (Garrnmitt>s): 262 nonekens is ( Anchura) : 295-296, 544 ('l't•rehrntulina): 2~. 70--71, 440 nodift>ra ( Pleurotoma) : :Vi 3 nod ulosa (Trigonia) : 1 2 7 nodosum (Hercorhyncus): 322, 323, 556 nodosus ( Hyclrotribulus) : 3:~ 1 quadrangularis (Scaµhit<.•s): 426, 427 (ScaphitC>s): :rn. 426 N oetling, Fritz: 4 3 nolani ( Breviarca) : 87-88, 89, 452 Index Nonacteonlna: 382-385 defte:u: 383-384, 580 arapboides: 382, 383, 580 ten1a: 384, 385, 580 tritlcea: 384, 580 North Carolina: 19, 25, 28 Norwich: 39 Nostoeeras: 407-414 aberrans: 21, 409-410, 594 colubriformis: 412-413, 414, 596 draconis: 411, 412, 413-414, 596, 598 heliclnum: 21, 41o-411, 412, 594 cra11um: U 1, 412, 596 bumile : 412, 596 hyattl: 410, 596 1tantonl: 21, 407-409, 410, 594 prematurum: 21, 409, 594 Notoscele1 bournei: 17 novemco1tata (Drlllia): S78 Nowak, Jan: 425 nuclforml1 (Cypraea) : 314, 31 5. 552 Nucula: 72-75 amlca: 7' cbatfleldensis : 73, 450 clboloenala: 72-73, 450 cunelfron1 : 7 4 eufaulensl1: 72 mlcro1trlata: 22, 74, 450 nacatocbana: 74-75, 450 percra11a : 7 S perequalis: 21, 72, 450 1lacklana: 73 1tantonl: 73 waltonen1is: 74, 450 Nuculana coloradoensis : 76, 450 ~orbetenals: 77-78, 450 coraicana: 75-78, 450 bou1tonl: 77, 450 lonaifrons: 44, 78, 450 plnnaforma : 7 6 pittensls: 79 travlaana: 76-77, 80, 450 whltfleldl: 76 Nudlva1ru1 : 294-295 cooperensis : 294-295, 542 1lmpliclu1: 295 Nuevo Leon: 35 Oak Grove, vicinity of: 50 Oatatoor aroup: 123 obllqua (Cinulia) : 390 obllquata (Polinices) : SO, 376 obnutu1 (Cadulus): 18, SO, 255-256, 526 ob1cura (Graphidula): S47 (Meaorphytis) : S 4 6 obtuelvolva (Gyrodes) : 2 7 8 ocalana (Fistulana) : 244 occldentalis (Acmaea): 18, 30, 256-257, 528 (Hamlnea): S92 (Mlcrabacia): 14 octollrata (Ficus) : 818, 319 octollratua (Napulus) : 28, 319, 320, 554 Odontofu1us: 888 curvlcoatatus: 338 typlcus: 388 Oddi, vicinity of: 58, 64 odden1l1 (Tltanosarcolites): 28, 80, 37, 184, 185­ 188, 494, 496, 498 Odum, Hilmar: 41 oldhaml (Hemlaster) : '3 (Parapachydiscu1): 85, S9, 41 oleodorsum (Lucina): 192, 502 Ollaoptycba: 390-391 americana: 88, 390-391, 580 Olivia dama: 861 purpurata: 861 etamlnea: 861 onyx (Hamulus): 58-60, 442 Ootatoor: 4 8 Ophthalmoplax stephensonl: 1 7 orlentall1 (Acteonina): S82 ornatula (Beretra): 377, 578 Ornop1l1: 342-.344 dl&Te11a: SU alennl: 8'2 maxeyl: 343, 588 pulcbra : 342, 8'8, 566 1oll1tella: 819, 343, 844, 566 Oatrea: 103-114 acutlro1trl1: 11O canallculata: 39 conseata: 80, 104, 105-107, 108, 480 conve:u : 116 curvirostris: 110 falcata: 111-113, 114, 482 mesenterica: 112 nasuta: 112 incurva: 39, 110 larva: 112 lima: 142 Junata: 39, 119 rnesenterica: 113-114 466 rnortoni: 105 ' owenana: 20, 21, 22, 103-104, 464, 466 panda: 39, 104-105, 464 plumosa: 19, 30, 39, 104 106 108-111 466 saltillensis: 108 ' ' ' ~emiplana: 39, 105 subspatulata: 104 tecticosta: 107-108, 462 triangularis: 110 vesicularis: 114, 115 Otatume, K.: 44 ovatus (Baculites) : 404 overana australis (Dakoticancer) : 1 7 overwegi (Exogyra) : 42 Owen, D. D.: 426, 435 owenana (Ostrea): 20, 21, 22, 103-104, 464, 466 Owl Creek formation: 22, 24, 25, 26, 28 Oxybeloceras: 399 oxypleura (Lima): 142 Oyau beds: 44 Pachycardium: 193-195 spillmani: 194 wadei: 194-195, 510, 512 Pachydiscus colligatus: 41 quiriquinae: 38 Paladmete: 366-369 alta: 367, 369, 576 cancellaria : 3 6 7 corbuliformis: 366, 367, 369, 490, 576 elegans : 368-369, 576 gardnerae: 368 inaequalis: 368, 576 Paleega williamsonensis: 17 Paleocene: 18, 27, 28, 29, 31, 32, 37, 38, 41 Palaeomorea haughtoni: 4 5 Paleosephaea : 355 mutabilis: 45 scalaris : 4 5 Palestine: 42 Palmer, Robert H.: 36, 37 Palmer Land: 38 panda (Ostren): 39, 104-105, 464 Panope: 241-242 decisa: 241, 242 elliptica: 242 monmouthensis: 241, 242 subplicata: 21, 241-242', 524 papillata (Thecidea) : 4 0 parabella (Tuba) : 269, 270 paracrassa (Corbula) : 4 2 Parafusus: 359, 572 callilateris: 359 coloratus: 359 parahillanum (Brevicardium): 203, 205 Parahyba do Norte, Brazil: 38 parahybensis (Sphenodiscus) : 38 Parapachydiscus: 33, 38, 418-422 arkansanus: 18, 21, 38, 39, 418-419, 422, 602, 604, 606, 608 colligatus: 35, 40 gollevillensis: 35, 37, 38, 39, 40, 43, 45 neubergicus: 35, 40 oldhami: 35, 39, 41 scotti: 419-422, 610 stallauensis: 37 parilis (Mysia) : 216 (Tenea): 216, 217-218, 518 Paris Basin: 40 parva (Lucina): 191 (Solyma) : 226, 520 parvilineata (Lucina): 18, 189, 500 Parvivoluta: 359-360, 572, 574 concinna: 859 parvus (Pecten) : 136 patelliformis (Anisornyon) : 80, 396 (Helcion): 395 patens (Pseudornalaxis): 258-259, 528 patula (Tellina): 220, 516 paucicostata (Drilluta): 353, 568 pauciplicatus (Pugnellus) : 311 pauperculurn (Dentaliurn): 18, 30, 254, 526 peasei (Etea): 172-173, 486 Pecan Gap chalk : 81 The Untl'ersity of Te:ras Publication No. 4101 Pecten: 130-139 aequicostatus: l :~Ii (Amusium) danl'i: 137-138, 478 archeri: 134-135, 1:~1i, 474 (Camptonectes) nrgillensis: 1:{2 bellisculptus: 4f>, 1 :~2 bubonis: 25. 131-133, 476 curvatus: 1 az halli : 1:~ ;{, 1:{ f> katfraria: 4f> kaufmanensis: 133, 476 lens: 1;{1 maximum : l :rn (Neithea) austitH•nsis: D7 bPXUl"l'llHiH: 136-137, 478 quinqueco::;tatus: ;{\I pnrvus: l :Hi (Pecten) v1...nustus: 130-131, 478 p)euroncl'lt>s: I :n quinquenarius: 1 :H~. l :~!I (H.adiopecten) mississippie11si::;: 138-139, 478 weeksi: l:{H ri1dda: 1 :~ :L 1:rn simplicius: 133-134, l :Hi, 1 :Hi, 474 (Syncyclonema) archeri: 134-135, l:lli, 474 halli: 1af> kingi: 135, 474 simplicius: 133-134, 474 travisanus: 135-136, 478 venustus: 2f> virgatus: I ;{2 pectiniformis ('frigonosemus): 40 pectinis ( Linearia) : 222-223, 514 pectorosa (Pholas): 25. 26, 251-252, 524 Peedee formation: 1 !), 22, 25, 26, 2H peinei ( Micraster) : liH pe)agicu covensis (Lima) : 14 2 woolseyi (Lima): 142-143, Hti, 147, 480 pelecyphora (Aporrhais): 40 perbrevis (Corbuln) : 2:rn percompressa (Pteria): 10:~ percra~rna (Nucula): 7a perequalis (Nucula): 21, 72,450 pergracilis (Anchura): a45 Periploma : 162 edward::ii: 162, 484 elliptica: 4 4 perimpressa (Troostella): :~~n. :~H2 Perissolax: :~ 1 H whitfieldi: :~IR. :nn. a2o Perissoptera bailyi: 45. 2!lH perlata (Pyropsis): :3rn-:n6 perlatus (Eutrephoc(•ras) : ;{ !IH Peron, M. A.: fii perovalis ( Breviarca) : Hti (Trigonarca) : Hli perplana (Scamhula): 1H2, 183, 486 Perriioonota littl(•i: i \J protexta : 7!l perryi (Spironema) : 272-273, 532 Persia: 4:{ Pervinquiere. L.: 42 petrosa ( Pteria) : 102. 1 0 :~ petrosus (Gyrodes) : 282-283, 526 Pettibone station: 4 7 Philadc>lphia, Acad(•my of Naturnl Scil'IH'C"• of: G PholadidPa: 246-247 fragilis: 247 ragsdall'nsis: 246-247, 522 Pholaclomya: 158-159 Iittlei: 21. 158-159, 468 Pholas: 251-252 pectorosa: 2f>, 26, 251-252, 524 Phyllochilus: :rn\1 Picard, Leo: 4 2 Pierre shah~: 1~. l~l. 21, 2:{, 27, 2K, 30, 3:3, lK·l Piestochilus: 350 cancellatus: :{ 4G levis: 350, 568 Pilsbry, H. A.: 6. K9 Pinella: 324-325 reticulata: 2~. 324-325, 554 pingue ( Axonocnas) : 423, 612 pinguis (Lucina) : 21 7 pinnaforma (Nuculana): 76 Pironaea syriaca: 4:{ pittensis (Nuculana) : 79 Placenticeras: 27. 431-434 intercalare: 1 ~. 30, 433-434, 622 meeki: 17, 11'1, ao. :rn. 431-433, 616, 618 (Sphenodiscus) lenticulare: :rn. 0 4, .t :l 5 Planoglobulina acervulinoideH: 42 planov£'nter ( Eutrephoreras): 2fl, 397-398, 584. 586 planulatum (Legumen): 216 plcnol•osta ( An!'hurn) : 299 546 pll'llllH (Turnus): 247 ' l'lesinst(•r: 68-70 Hllll'l'i('llllllS: :!f1, :rn, 69-70, 448 Plt.•urisPpta (Splwnodhu·us): 2r1, 436-437, 624 Pleurotoma minor: :Vio nodift>ra: :Vi:~ pleuront:'t'tt's ( P(•den) : 1:n l'licatula: 140-142 clarki: 141 mullicaensis: 2!i, 26, 140-141, 478 tetriea: 141, 478 urti('osa: 140 l'lummer. F. B.: 5, G, 4\lO Mrs. F. H.: 5 plummeri ( Breviar('a): 87, HH, 452, 490 plumosa (Ostrea): Ul, ao, :rn, 10·1, IOii, 108-111, 466 poinsettiformis ( PtNOl'Nellu) : 40, 309-310, 550 Poland: ;{\l, 41 Polinict'S: 276-278 coneinna: 277 halli: 276 obliquata: 30, 276 reetilabrum: :n. ao. :rn. 276-277, 534 l<'xanus: 277-278, 534 ~teph(•nsoni: 21, 278, 534 polymorphus ( M yt ilus) : l 5ti 1'o nwI. N. A . : 6 H ponderosa (J<;xog-yra): l!l, :rn, 121, 12G pondi (Epitonium): :!!i, 266-267, 530 l'ondil'ht'rry: 4:{ Pondoland: 44 Portloek, J. K: !if> Powell, vicinity of: fi2 POW(•rsi (IdonearC'a) : 90-91, H2, 454 Prat>harrPt t ia : :rn. :n Prairie Bluff ehnlk: 22. 24, 25, 2ti, :!H, :lf1, f>6 Prt•maturum (Nostoct'l'as): 21, 409, 594 producta (Ca Vl'oln) : 364-365, 574 propinqua ( Aporrhais) : 4 0 (Cultrig('l'a) : 4 0 Prorast('l': 6:~ Proscala: 267-268 americana: 21, 267-268, 530 protexta (Leda) : 7 !I (Liopistha): 4:l, 162-164, 486 ( Perrisonota) : 7!l Protohusvcon cretaet.'llm: :{24 Protocar. 2fi, 29 1•roxima (Pyropsi::;): :ne (Srnla): 4:l (Turris) : :Vi H proximus ( Inm'(•ran111s): !)\) l'spudoliva ath•nuatn: :n:!, :17:~ ]'seudomalnxis: 258-2'59 nmplifleata : 2!i7 patt•n,.;: 258-259, 528 riµlt>vana: 2!i7, 2f>~) zanclaea: 2f>!) Ps('tlllomelania: 265 rnonmouthensis: 21if> runnelsi: 2!i5, fi:lO Pseudomorea: il2H Pseudotextularia vnrians: 41, 42 Pt<>ria: 101-103 linguadormis: 21, 2a. ao. 102-103, 458 percompressa: l O:l petrosa: 102, IO:l Pterocerella: 309-310 poinsc>ttiformis: 40, 309-310, 550 tippana: 31 0 pteropsis (Crassatc>lla): 17(), 179 PtychocPras erassum: 3HH Puerto Rico: :17 Pug-n e 11 us : 4 5, 4 6 , 31 0-313 crassicostatus: 4:l d(•nsatus: 4a, :nl, 312 nacatochanus: 310-312, 550 pauciplicatus: a11 robustus: 312, 550 pulchella (Ringicula): 21, 387-388, 389, 490, 580 pulchra (Ornopsis): 342, 34:J, 566 Pulvinites: 151-152 adansonii: 151 argenteus: 151-152, 482 Index 637 pumila (Cyclorisma): 218-219, 512 (.Margaritella) : 272, 532 pumilis (Scaphites): 426-427, 614 Purpura: 326 purpurata (Olivia): 361 Pycnodonte radiata: 114, 115 vesicularis : 4 2 Pyramidella dolatrata: 263 (Longchaeus) mazatlantica: 263 pyriformis (Lupira): 36~361, 572 Pyrifusus granosus: 319 monmouthensis: 336 subdensatus: 336 Pyropsis: 315-316, 552 geversi: 45, 325 lanhami: 315-316, 552 lenolensis: 319 perlata: 315-316 proxima : 31 6 whitfieldi: 318, 319 Pyrula trochiformis : 316 Quaas, A.: 42 quadrangularis (Scaphites) : 4 2 6, 4 2 7 quadrilaterus (Leptosolen) : 228, 520 quadrilira (Turritella): 29, 287 quadriliratus ( Drepanochilus) : 308, 309 Quinlan, vicinity of: 49, 50, 51, 52 quinlanensis (Crassatella) : 176, 179, 488, 490 quinquescostatus (Neithea) : 39 (Pecten): 39 quinquenarius (Peeten) : 138, 139 Quiriquina beds: 38 Island: 88 quiriquinae (Pachydiscus) : 38 radiata (Pycnodonte): 114, 115 Radiolites nicaisei: 187 Radiopecten: 138-139 mississippiensis: 138-139, 478 weeksi: 138 Raftnesque, C. S.: 89 ragsdalensie (Pholadidea) : 246-247, 522 ramoni (Scintilla): 193, 502 Ramsetia: 250-251 whitfteldi: 250, 251, 524 Rapa supraplicata: 280 Rathbun, Mary J.: 15 Reboul, P.: 38 rea8'ani (Aliofusus) : 336-337, 562 1ubtilis (Aliofusus): 337, 562 tumidus (Aliofusus) : 337, 562 recta (Cylfchna): 395 rectilabrum (Polinices): 30, 33, 276-277, 534 texanus (PoJinices) : 21, 277-278, 534 Red Bank sand: 23, 26 Red River County: 10, 4 8 Redus Well No. 1: 50 Redwood, vicinity of: 4 9 Reeside, J.B., Jr.: 6, 34, 111, 125, 184, 417, 425, reesidei (Dasmosmilia): 15 (Solenocerae) : 401-402, 588 reftexum (Anaklinoceras): 18. 414-415, 600 regularis (lnoceramus): 42, 44, 45 Rehder, Harald A.: 6 Remera : 344-345 decora: 345, 564 microstrlata: 344-345, 564 Remnita: 379-380 biacuminata: 21, 379-380, 578 Rennie, John V. L.: 44, 29R, ::425 Research Institute, Univer~ity of Texas: 5 reticulata (Lima): 147 (Morea): 327 (Pinella): 28, 324-325, 554 (Tuba): 261, 270 retifer (Fusus) : ::\ 19 (VoJutomorpha): 21, 355-356, 570 ReuHia limbata: 42 riddelli (Solidula) : 3 81 rhrlda (Pecten) : 133, 13!) Rio de Oro formation : 3 7 Rio Grande region: 29 rimosus (Turbo): 40 Rin8'icula: 387-390 anfractolineata: 389, 580 culbersoni: 388-389, 580 pulchella: 21, 387-388, 389, 490, 580 sufftata: 389-390, 580 Ripley formation : 18, 19, 21, 22, 25, 26 ripleyana (Beretra) : 3 7 5 (CrauatelJa): 177 (Exilia) : 870 (Ga•trochaena): 25, 244-246, 528 (Lithophaga): 155, 156 (Lucinn): 191 (Mathilda) : 270 ( Pseudomala:x:is) : 257, 259 (Turricula): 375, 376 (Turris): 375 ripleyanum (Dentalium): 252, 253, 254 Roane, vicinity of: 53 roanensis (Discoscaphites) : 30, 428-429, 614 robertsi (Fusus) : 334, 562 robusta (Laternula): 44, 16~161, 484 robustus ( Bellifusus) : 339, 340, 564 (1'.,usimilis) : 378-379, 578 ( Pugnellus) : 312, 550 Roca formation : 3 8 Rocellaria : 2 44 rockf'nsis (Belliscala) : 268, 532 (Corbula): 237, 239, 490, 522 Rockwall County: 11, 4 6 Roemer, F.: 162 Rosali, vicinity of: 4R Ross, Gene: 5 rossae (Cardium): 197-198, 506 (Granocardium): 197-198, 506 Rostellaria americanl': 305 rostrata: 298 Rostellites texana: 3 rostrata (Anchura) ~ JOO (Rostellaria): 298 Rouss~lia: 184 rotundata (Glycymeris) : SIS kaufmanensis (Glycymcris) : 84-85, 452 rotundum (Axonoceras): 424, 612 rotundus (Gyrodes) : 25, 281-282, 536 Rouchadz~. J.: 414 Roudaireia undata: 42 rugatum (Glyptoxoceras): 37 rugosus (Scaphites): 18, 21, 30, 425-426, 612 runnelsi (Pseudomelania): 265, 530 Russia: 39, 41 rutoti (Sphenodiscus): 35, 40 saffordi (Barbatia): 88 (Breviarca): 86 (Trigonarca): 86 Saghalien: 44 Saint-Aignan: 40 salinaensis (Protocardia) : 203 saltillensis (Ostrea): 108 Samac: 36 San Antonio, vicinity of: 50, 51, 52 San Diego: 36 sandstone, fossiliferous: 6, 490 San Gabriel River: 53 San Luis Potosi, Mexico: 20, 23, 29, 36 San Miguel formation: 21, 28 Santa Anita formation: 38 Santonian: 34. 44 Saratoga chalk: 19, 22 Sargana: 325-326 stantoni: 18, 21, 45, 325-326, 554 Saskatchewan: 35 Sass, L. C.: 37 Raundersorum (Turrilites) : 416-417, 600 Sauvagesia: 187-188 acutocostata: 188 coloradoensis: 188 hilli : 187-188, 500, 502, 504, 506 Say, Thoma~: 116 sayrei (Lima): 146-147, 480 Rcabellum (Cymbophora) : 229-230, 232, 233, 520 ~cabra (Trigonia): 127 Scabrotrigonia: 127 Scala binodosa: 261 calamistrata: 42 proxima: 43 sillimani: 267 scalaris (Paleosephaea) : 4 5 Scambula perpJana: 182, 183, 486 Scaphander: 391 lhrnarius: 391 (Mirascapha) costatus: 391 Scaphites : 425-428 brevis: 23, 30, 33, 427, 614 conradi: 429 hippocrepis : 3 4 nodosus: 30, 426 quadrangularis: 426, 427 pumilus: 426-427, 614 rugosus: 18, 21, 30, 425-426, 612 yorkensis: 427-428, 614 scaphoides (Goniochasma) : 249-250, 526 scarboroughi (Fusus) : 350 scatesi (Tornatellaea) : 385, 580 Schizaster atavus: 65 The Unl'.-uersify of Tc;ras Publication No. 4101 Schizodesma apprf's!"a: 2:l0 SchJoenbachia: 4 4 schlotht-imi (Lispode!"thcs): 2!l8 Schluter, ClemC'nts: 67 schmidti (lnoceramus): 34 Schuchcrt, Charles: :~2. 404 Schumacher, Cri>tien Fre~l sexsulcata: 5!l Seymour, island of: 38 Shumard. Il. F.: 7. 20~. :rnr;, :l 1!1, :l 70. :l~ 1 shumardi (lsocardia): 207-208, 508 Shupe, N. W.: 6 Siderastrea cretacea: 14 Sikotan formation: 44 sillimani ( Epitonium) : 42, 261l (Scala): 267 simplicius (Nudivagus) : 2!1fi (Pecten) : 133-134, 13fi, 136. 474 (Syncyrlonema): 133-134, 474 Simpson's Hill. vicinitv of: 4 R 1.:dmpsonense (Cerithiu~1): 294, 542 simpsonensis (Cym bophora) : 233, 520 (Hamin<'a): 394, 582 minola): :~2!l Solid11la riddelli: 3Rl soJiRt<'IIa (Ornopsi!'): 3lfl, 343, 344. 566 Solyma: 224-226 Jrardnerac>: 225, 520 lineolat11s: 22fi parva: 226, 520 Sopockinie: 41 South America: 37. 4 4 Sowerby, James: 58, 9~ l'pang)eri (Capulus) : 21, 23, 30. 3 3. 273-274, 532 Spatangus bufo: 63 coranguinnm: 6R ]acunol'US: 6fi Spath. L. F.: 37. 44. 3!1!1 spathi (Sphenodiscus) : 42 speciosum (Cardium) : 1!:15 S1wnJZ"ler, Lorentz: 242, 243 Sphal'rttlit<'s lusitanicus: 187 Sphf'nodiscus: 20, 2:{, 24, 26, 27, 29, 33, 35, 37, 42, 4:l, 434-437 IH'lltodorsatus: 4!\ 1tllisonensis: 4:Hi hinl'khorsti: :{Ii, 40 brazili<•rn;;is: 38 konicki: 3fi IC'ntil'ulare: 434 kntic11laris: :rn. 4:14, 435 Iobatus: 26, 431) allisonensis: 43fi parahybensis: 38 pleuriseptn: 25, 436-437, 624 rutoti: 35, 40 spathi: 4 2 stantoni: 42 tirensis: 2!l, 30, 435-436, 437, 620, 622 uhagshi: 3fi, 40 Spillman, W.: 286 spillmani (Cardium) : 1 !l:l, 1!H (Gyrodt's): 2Ra. 284, 538 ( rachycardium) : 1!l4 spinifera ( Exogyra) : 125-126, 476 spinosus (Trochifusus): 317 Spironema : 272-273 perryi: 272-273, 532 h>nuilinPata: 273 Spis11ln (Cymhophora) C'ZOC'nsis \'Rr. hetonniensi": 44 sph·ndidus (Turrilite!-1): 21, 415-416, 598 Spond:dus: 139--140 grl'galis: 140 minitus: 139--140, 482 Spring<'r. Frank: :14 sq11amos11s ( HamnhtR): 2R. 60-61, 442 sq11amulos11s (Turbo): 2fi\I squnrosa (Lima): 14:l stalla11c•nsis ( rarapal'hydisc11s): :n stnminPa (Oliv11ln): :mt Stanton. T. W.: Ii, 34, 111, 2Rfl. 3!l!l, 404 Stanton<'lla: :l:l~ stantoni aberrans (Nostoccrns): 21, 409-410, 594 (Cardium): l!l4 (N<'modon): 81 (Nostoc<'ras): 21, 407-409, 410, 594 (Nncula): 73 ( Pachycarn, J. A.: 181 uddeni (Volsella) : 152-153, 484 Uddenia: 180-182 conradi: lRO, 181, 1R2 te.xana: 181, 486 Ulricelunlla): 4fl. 17'1. 178. l>l-0 manorE'nsis (('rassat<-lla): 177-178, 492 wacl<'i (C'rassatPJla): 177 vanustus (Peden) : 2fl, 130--131, 478 Vermunt. L. W .•J.: :rn. :n vc>rsus (Capulus): 27fi V('rtehroisi (Turritc>lln): 290-291, 540 leoni (Turritella): 291, 540 longi (Turritella): 291, 540 t<'nuispira (Turritella): 290, 2!'11, 548 (Turritella): 290, 2!H, 2!l3 vesicularis (GryphaNl) : 41, 4 3, 116, 11 R ( ()Stl"('R ) : 114, 1 11) ( Pycnodontt>) : 4 2 Vctcricardia: 174, 175-176 <'renaliratn: 17fi gregaria : 176 suhangulatn: 176 l"ulwireula: 17fi wehhervillensis: 175-176, 486 virgatus ( P<'<'ten) : 1a2 Volsella: 152-153 uddc>ni: 152-153, 484 Voluta ampln: 361 tornatilis: :~RO Volutilithc>s navnrro<'nsis: 3fi7 Volutorg<': :rn. 40, 41 voragiformiH ( Architc>ctonica) : 271, 530 Vr0nver, C. F..: :lR W chher ville, vicinity of: 52, fi4 W(•hlH'rvill<>nsis ( BrPviarca) : ~8-89, 452 (VetPricnrdia): 175-176, 486 We<'kPrl:v. C. A.: 6 W e<'ks, Da vc: 2fi7 weeksi ( Pecten) : 1 :H~ (Radiopectc>n): 1:-JH We<>ksia: 257-258 amplificata: 2fi7, 25R lubbocki: 258, 528 Welln, Stuart: fl, !:13, 112, 127, 154, 210. 211, 225, 229, 2:30, 242, 246, 247, 250, 278, 383 Index 641 welleri (Cardium): 195-198, 502 (Ethmocardlum): 195-198, 802 Welle, John W •.: 11, 98 wellei (Gervillia): 97-98, 454 wenonah (Cardium): 196 Weat Coast: 88 West Indian islands: 29 resion: 83, 86 West Indies: 86 Western Interior: 18, 19, 21, 23, 26, 27, 28, 29, 80, 83, 86 Weetpbalian Basin: 40 Wetherill, Samuel R.: 124 Wheeler, 0. C.: 38 White Chalk: U White, Charles A. : 6 whltel (Cardlum): 196, 196 (Creonella): 283-264, 266, 530 (Ethmocardium): 196, 196 whlteleyensie (Glycymeris): 86 "\V'bitee Chapel, vicinity of: 49 Whitfield, R. P.: 6, 87, 136, 183, 225, 242, 250, 278, 318, 888, 892, 400 whitfteldl (Gastrochaena): 246 (Napulue): 819 (Nuculana): 76 (PeriBBolax): 230, 818, 319 (Pyropaia): 818, 819 (Ramaetia): 260, 251, 624 whltneyl Xylopbagella): 247, 248-249, 250, 522 Wieser, Frances: 6 wleserae (Llnearfa) : 222. 224, 514 wteaerl (Ani0 omyon): 267, 396 Wllckene, Otto: 46 Williamson Count:v: 14, 23, 63 wfllfam1onen1fq (Palaega) : 17 williardi (Corbula): 21, 235-236, 237, 522 winchelli (Turritella): 21, 289, 540 Wolfe City sand : 31 Woodbine sand: 31 woodi (Corbula): 239, 522 Woodring, W. P.: 6, 37, 86, 183, 244 Woods, Henry: 39, 44, 45, 105, 110, 116, 119, 132, 156, 204 Woodward, Samuel: 110 woolmani (Trochocyathus) : 11 woolseyi (Lima): 142-143, 146, 147, 480 Xancus variabilis: 360 Xenophora: 284-286 conchyliophora: 285 leprosa: 284-286, 538 Xylophagn elegantula: 247 stimpsoni: 249 Xylophagella: 247-249 elegantula: 247, 248 whitneyi: 247, 24&-249, 250, 522 Yabe, H.: 44 Yoldia: 78 hakobutenqis: 44 yorkensis Scaphites) : 427-428, 614 zanclaea (Pseudomalaxis): 259 Z'lria fignrii: 42 Zeltberg: 40 zitteliana (Crassatel1a): 45 zone of Exogyra cancellata: 19, 22 of Exogyra costata: 19 of Exogyra ponderosa : 1 9 of Micraster co-anguinum: 34 Zorn, vicinity of: 52 Zuehl, vicinity of: 52 Zululand: 44