publications of the INSTITUTE of MARINE SCIENCE Volume 9 I December, 1963 Published by the Institute of Marine Science The University of Texas Port Aransas, Texas publications of the INSTITUTE of MARINE SCIENCE Volume 9 I December, 1963 Published by the Institute of Marine Science The University of Texas Port Aransas, Texas ERRATA FOR PUBLICATIONS OF THE INSTITUTE OF MARINE SCIENCE, VOL. 8 Page 6, Table 2, Column 4. Read "Total fishes" instead of "Other fishes." Page 6, Paragraph 2, Line 3. Read "July 17" instead of "July 7." Page 163, Paragraph 2, Line 10. Read " 17.4%0 " and "31.2%0 " instead of "17.4%" and "31.2% ." Page 98, Line 17. Delete one "and Pachygrapsus." Page 98, Materials and Methods. Definition of 100% SW omitted. Oceanic SW of [Cl]= 540mM/ L was used as 100% SW. Page 101, Line 18. mgrn. S04, instead of MgSO •. Page 103, Figs. 2 & 3, 4 & 5. Graphs and legends interchanged, note labels on ordinates. Page 104, Fig. 7. Legend-delete "from Table 7." Page 104, Figs. 8 & 9. Legends and graphs interchanged. Page 105, Figs. 10 & 11. Legends and graphs interchanged. Page 109, List of conclusions. #'s 1 & 2, "hypo-tonic" instead of "hypo-osmotic." Page 109, 3rd from bottom . . "Blood osmotic concentration" instead of "blood pressure." Page 117, 26 from bottom. "Table 12" instead of Table 5." Page 121, 21 from bottom. Substitute "from the Laguna" for "from Austwell." Page 123, Summary, #1. Substitute "Blood and-" for "Blood of-." PUBLICATIONS OF THE INSTITUTE OF MARINE SCIENCE Staff for Volume 9 Mrs. Anne Wilkey, Ediitor; Bill Gillespie, Art Editor; Howard T. Odum, Scientific Editor. The Publications of the Institute of Marine Science is printed by The University of Texas and includes papers of basic or regional importance by Gulf workers or on Gulf waters, in the fields of Bacteriology, Botany, Chemistry, Geology, Meteorology, Physics, Zoology, and other marine sciences. Papers are read by three referees; papers by the editors are processed by the Chairman of the Budget Council. Authors should submit manuscripts to the Director, Institute of Marine Science, Port Aransas, Texas. In most respects the Style Manual for Biological Journals of the American Institute of Bio­logical Science is used (2000 P St., NW, Washington 6, D.C.). Bibliographic abbre,-iations follow World List of Scientific Periodicals. EDITORIAL ADVISORY COMMITTEE OF THE PUBLICATIONS W. Frank Blair, Department of Zoology, The University of Texas, Austin, Texas. Harold C. Bold, Department of Botany, The University of Texas, Austin, Texas. Albert Collier, A. and M. College of Texas, College Station, Texas. R. L. Folk, Department of Biology, The University of Texas, Austin, Texas. Marcus A. Hanna, Gulf Oil Corporation, Houston, Texas. Willis G. Hewatt, Department of Biology and Geology, Texas Christian University, Fort Worth, Texas. Donald W. Hood, Department of Oceanography, A. and M_ College of Texas, College Station, Texas. Sewell H. Hopkins, Department of Biology, A. and M. College of Texas, College Station. Texas. Clark Hubbs, Department of Zoology, The University of Texas, Austin, Texas. Edward Jonas, Department of Geology, The University of Texas, Austin, Texas. R. J. LeBlanc, Shell Oil Company, Houston, Texas. Howard T. Lee, Texas Game and Fish Commission, Austin, Texas. W. Armstrong Price, Wilson Building, Corpus Christi, Texas. Cecil Reid, Sportsman Club of Texas, Austin, Texas. Robert 0. Reid, Department of Oceanography, A. and 1\1. College of Texas, College Station, Texas. AVAILABLE IS5CES (For a listing of contents, refer to Volume 7, page 315) Volume Number Year Pages tList Price I 1 1945 190 1out of print) I 2 1950 194 I out of print) II 1 1951 212 $2.15 II 2 1952 215 $2.40 III 1 1953 224 $2.15 III 2 1954 131 1out of print) IV 1 1955 302 $2.65 IV 2 1957 341 1out of print) 5 * 1958 492 $4.40 6 * 1959 403 $4.15 7 * 1961 319 S4.15 8 * 1962 410 $4.15 9 * 1963 (this issue) $4.15 *Standing orders for subscriptions may be placed at $4.15 per year. Please make che k h · · f T s· c or pure ase order payable to The Umverslty o exas. mce 1958 one volume has been printed _ ( issue) . per year one t Prices include postage. Please add 2o/o sales tax. INSTITUTE OF MARINE SCIENCE, THE UNIVERSITY OF TEXAS PORT ARANSAS, TEXAS 1962 The Institute of Marine Science with laboratories at Port Aransas, Texas is a research division of The University of Texas related to the Departments of Microbiology, Botany, Chemistry, Geology, Physics, Zoology, Civil Engineering and the Meteorology Division of Aerospace Engineering at the Main University at Austin. An integrated teaching program in graduate marine science is made up of the course offerings from the several departments and from the Institute. Staff and Students for 1962 INSTITUTE OF MARINE SCIENCE Howard T. Odum, Ph.D., Director, Graduate Advisor, Lecturer in Zoology, Research Scientist. Budget Council: S. P. Ellison, Jr., Chairman; Jack Myers, Harold Bold; tH. T. Odum. ECOLOGY PROGRAM tRobert J. Beyers, Ph.D., National Science Foundation Postdoctoral Fellow, Research Scientist Associate III *Clyde A. Allbaugh, Research Scientist Associate I. +*Ronald Wilson, M.S., Research Scientist Assistant II. +*Neal Armstrong, B.S., Computer Programmer I. Bill Gillespie, A.A., Laboratory Research Assistant I. Cathy Smith, Laboratory Research Assistant I. *John Landolt, Laboratory Attendant. *Tommy Brayshaw, Laboratory Attendant. GEOLOGY PROGRAM tE. William Behrens, Ph.D., Research Scientist Associate III (Marine Geology), Lecturer in Geology. :!:*Cader Shelby, M.S., Research Scientist Assistant I. MICROBIOLOGY PROGRAM tChase Van Baalen, Ph.D., Research Scientist Associate IV (Marine Microbiology), Lecturer in Botany. James Earl Marler, B.S., Research Scientist Assistant I. *Mrs. Mildred Stewart, B.S., Laboratory Research Assistant II. Phyllis Sims, Laboratory Research Assistant I. *Douglas Hoese, Laboratory Research Assistant I. ICHTHYOLOGY PROGRAM John C. Briggs, Ph.D., Research Scientist (Marine Ichthyology), Lecturer in Zo(}logy. :t:*Frank J. Little, M.A., Research Scientist Associate I. +*Robert S. Jones, B.S., Research Scientist Associate II. *Henry Compton, B.A., Research Scientist Assistant I. *Ronnie Scharlock, Laboratory Attendant. CHEMISTRY PROGRAM *Patrick L. Parker, Ph.D., Consultant, Carnegie Geophysical Laboratory. Ann Gibbs, Research Scientist Assistant I. MARINE RESOURCES PROGRAM tBilly Joe Copeland, M.S., Research Scientist Associate III. *William B. Ogletree, P.E., Research Engineer Associate II. Robert S. Jones, B.S., Research Scientist Associate II. *Donald B. Wilson, B.S., Technical Staff Assistant III. *Wayne Flenniken, Laboratory Research Assistant I. AIJMINISTRA TIVE STAFF tJohn Thompson, B.B.A., Administrative Assistant. Mrs. Anne Wilkey, Technical Reports Editor. Mrs. Helen Brown, Senior Secretary. Mrs. Gen Southern, Secretary. *Betty Jo Armstrong, Clerical Assistant *Mrs. Johnnie Morgan, Clerk-Typist. *Mrs. Sharon Cobb, Clerk-Typist. Herman Moore, Motorboat Operator. *Don Franklin Nutt, Motorboat Operator. Jesse Esparza, Maintenance Man. Carrol Lee Martin, Maintenance Man. Jesse Dickerson, Building Attendant. Minor Hendricks, Building Attendant. *Reece Brown, Laborer. *Mrs. Lois Rosencran, Cook II. *Winfred Siverand, Food Service Worker. VISITING PROGltAM lN 196:! Visiting Investigators' Research Programs Robert Folk, Ph.D., Associate Professor, Department of Geology, The University of Texas. :!:*Miles Hayes, Research Scientist Assistant II. Calvin MacMillan, Ph.D., Associate Professor, Department of Botany, The University of Texas. t*James Pipkin, Research Scientist Assistant I. E. F. 'Gloyna, Ph.D., Professor, Department of Civil Engineering, The University of Texas. t*Albert Story, U.S. Public Health Service, Assigned for training. Clark Hubbs, Ph.D., Associate Professor, Department of Zoology, The University of Texas. t *Hinton D. 'Hoese, Research Scientist Assistant II. Meredith L. Jones, Ph.D., Assistant Curator, Department of Living Invertebrates, The American Museum of Natural History, New York, New York. Visiting Lecturer, NSF Institute. Robert Z. Brown, Sc.D., Professor of Zoology, Department of Zoology, Colorado College. Exalton A. Delco, Jr., Ph.D., Associate Professor of 'Biology, Huston-Tillotson College, Austin, Texas. Visiting Classes Del Mar Junior College Science Club, South Texas College Biology Society, University of Texas Geology Classes, University of Texas Zoology Classes, University of Illinois Botany Class, Arlington State College Class, University of Houston Class, Summer Science Training Program for High­ability Secondary School Students Class of The University of Texas, Texas A & I Biology Club, East Texas State College Biology Class, and Del Mar College Biology Class. NATIONAL SCIENCE FOUNDATION SUMMER STIPENDS FOR ADVANCED STUDY IN MARINE SCIENCE David Flyr, Richard Tubb, Wayne Hadley, Neal Armstrong, C. Kurt Lamber, Johanne Windle, Clyde A. Allbaugh, Mrs. Marjorie Putz, Reavis Lindsey, Hinton D. Hoese. t Student for a graduate degree. * Summer, or intermittent. t Resident Advisory Council. Table of Contents Institute of Marine Science, Staff and Students for 1962 ........................................... . III Helicopter Borne Purse Net for Population Sampling of Shallow Marine Bays. Robert S. ]ones, William B. Ogletree, John H. Thompson, fr., and Cdr. Wm. Klenniken, USN --------------------------------------------------------------------------------------------············ 1 Buried Pleistocene River Valleys in Aransas and Baffin Bays, Texas. E. William Behrens · · -----------------------------------------------------~------------------------------------------7 A Characteristic Diurnal Metabolic Pattern in Balanced Microcosms. Robe rt J. Beyers ------------------------------------------------------------------------------------------------·.... . . . 19 Cobalt, Iron, and Manganese in a Texas Bay. Patrick L. Parker, Ann Gibbs, and Robert Lawler --------------------------------------------------28 Radioactive Fallout in Sargassum Drift on Texas Gulf Coast Beaches. Cadar A. Shelby ----------------------------------------------------------------------------------------------------···· 33 Seasonality of Larger Animals in a Texas Turtle Grass Community. H. D. Hoese and R. S. ]ones --------------------------------------------------------------------------------------37 Productivity Measurements in Texas Turtle Grass and the Effects of Dredging an lntracoastal Channel. Howard T. Odum ------------------------------------------------------------------48 Amino Acids in Redfish Bay, Texas. Kilho Park, W. T. Williams,]. M. Prescott and D. W. Hood ----------------------------------59 Organic Carbon Levels in Some Aquatic Ecosystems. Ronald F. Wilson ------------------------------------------------------------------·---------------------------··· 64 Seasonal Plankton Productivity in the Surfzone of a South Texas Beach. William N. McFarland ----------------------------------------------------------------------------------------------77 Seasonal Change in the Number and the Biomass of Fishes from the Surf at Mustang Island, Texas. William N. McFarland ------------------------------------------------------91 Growth and Decay of Penicillus capitatus Lamarck in the Lower Laguna Madre of Texas. Lazern 0. Sorensen ---------------------------------------------------·--------------------------------106 Notes on the Fringed Pipefish, Micrognathus crinigerus, from the West Coast of Florida. Charlie R. Powell and Kirk Strawn ---------------------------·----------------------------112 Cell-Diameter Frequency Distributions of the Planktonic Diatom Rhizosolenia al,ata. Robert A. Woodmansee --------------------------------------------------------------------------------------------117 Distribution of the Zooplankton in the Salt Marshes of Southeastern Louisiana. Rene P. Cuzon du Rest ----------------------------------------------·-----------------------------------------------132 Oxygen Metabolism of Four Oklahoma Farm Ponds. B. !. Copeland and W.R. Whitworth ---------·--------------------------------------------------------------156 New Additions to the Bryozoan Fauna of the Gulf of Mexico. Robert Lagaaij_____ __ ____ 162 A Study of the Diatom Flora of Fresh Sediments of the South Texas Bays and Adjacent Waters. E. !. Ferguson Wood --------------------------------------------------------------------237 Shallow Marine Sediments Offshore from the Brazos River, Texas. ! ames H. Nienaber ---------------------------------------------------------------------------------------·--------. 311 Experiments With Engineering of Marine Ecosystems. . Howard T. Odum, Walter L. Siler, Robert]. Beyers, and N eal Armstorng 373 Diurnal Metabolism, Total Phosphorus, Ohle Anomaly, and Zooplankton Diversity of Abnormal Marine Ecosystems of Texas. Howard T. Odum, Rene P. Cuzon du Rest, Robert !. Beyers, and Clyde Allbaugh ------------------------------------------------------------404 Directions for the Determination of Changes in Carbon Dioxide Concentration from Changes in pH. Robert !. Beyers, lames L. Larimer, Howard T. Odum, Richard B. Parker, and Neal, E. Armstrong --·---------------------------------------------------------454 Chronological Record of Contributions from the Institute of Marine Science 1961-1962 -------------------------·--------------------------------------------------------------------------490 Helicopter Borne Purse Net for Population Sampling of Shallow Marine Bays1 ROBERT s. }ONES, WILLIAM B. OGLETREE,2 JOHN H. THOMPSON, JR., AND WM. FLENNIKEN, USN3 Institute of Marine Science, The University of Texas, Port Aransas, Texas Abstract A new technique has been developed for sampling animal populations in marine bays. A helicopter­borne net is utilized to trap an area of about l/40th of an acre (100.4 sq. m.). The net shape is maintained by a light weight, circular, aluminum frame 50 feet in diameter. The net is released in the drop zone by means of an electro-magnetic suspension system, and pursed by boat. Data taken in Corpus Christi Bay (Texas) showed an average biomass of fishes to be 107.7 lbs per acre, ranging from 44.8 to 165.6 lbs per acre (wet weight). Introduction The difficulty of estimating aquatic animal populations on a per unit area basis is well known (Hellier, 1962). For the past five years the University of Texas Institute of Marine Science has attempted to estimate stocks in the marine waters of the Texas Coast. Hellier (1959, 1962) contributed the first method in his study with the Drop Net Quadrat for sampling of the shallow areas of Laguna Madre. His device was suspended from pilings and thus had the disadvantage of being limited to shallow water. In addi­tion, Hoese and Jones ( 1963) in a later study of Redfish Bay, a shallow turtle grass community, found that after the net was dropped the necessity of removing animals from the quadrat by seining destroyed the habitat and was impractical for capture of more agile species. Next, the stocks of the beach zone were sampled for a year with a special beach seine by a team led by W. N. McFarland (1963) . These methods were not suitable for the deeper bays and a new method was needed where waters were four to fourteen feet deep. After considerable trial and error, a method involving helicopters was finally evolved. Methods Descrip~ion. There is a semi-rigid frame for maintaining the horizontal shape of the net (Fig. 1). This frame forms a circle of 50 foot diameter and is constructed of thin­ 1 This study was supported by an inter-agency contract between the Institute of Marine Science and the Texas Game and Fish Commission (Contract No. 4413--578), Dr. H. T. Odum principal investigator. 2 Consulting Engineer, Corpus Christi, Texas. 3 Flying Safety Officer, U.S. Naval Air Station. Helicopter Borne Purse Net =""4_:ll--· -.­ ~------· J --·-.. _____ _.. .. ..-..--. --~~~~/-- Frc. L Complete device, airborne and ready to deliver, with the various parts and lines noted. walled aluminum tubing braced in the horizontal plane by 3/ 32 inch stainless steel cable rigging. A second series of similar cables form a conical hoisting bridle. From this structure is suspended a right circular cylindrical nylon net of 3/ 4 inch stretch mesh. The cylinder is 15 feet deep, is weighted with 5/ 16 inch galvanized chain, and has a Helicopter Borne Purse Net standard net float line. Upper and lower pursing lines of 1/ 2 inch nylon are rove through galvanized steel rings sewn into the mesh. The net is suspended from the frame by a series of small electro-magnets. Flexible connections are used to fasten magnets to the frame and magnet keepers to the net float line. The power supply is a 15 volt, high amperage, dry cell unit to serve the primary series circuit of magnets. A 4.5 volt reverse polarity dry cell unit is used to overcome residual magnetism for rapid uniform release of the net. The trigger device, mounted in a pistol grip, has a three position switch. The first position closes the primary circuit through the magnets; the intermediate position is off, and the remaining position is a spring loaded momentary switch to put the depolarizing unit into the circuit. Total dry weight of the device is 540 lbs. The delivery aircraft used thus far is a Navy HRS-3 helicopter (manufactured by Sikorsky Aircraft). It has a lift capacity of 800 lbs with a limited fuel load. The crew for these drops consists of the pilot and one air crewman. Operating Procedure. The electrical circuit is energized and keepers are positioned to complete the magnetic circuit. The device is then attached to the helicopter cargo sling via a 50 foot length of 1/ 2 inch manila line and the hoisting bridle. Power supply and trigger are now placed aboard the aircraft. A jettison release on the cargo sling enables the pilot to drop the entire device should an inflight emergency develop. The aircraft rises vertically with the air crewman tending the slack rigging until it becomes taut and the stretched skirt of the net is lifted clear of the ground. At this time the pilot "transi­tions" from vertical to horizontal flight and is dispatched by radio to the drop area while maintaining a gradual climb to an altitude of 500 feet (Fig. 2). Optimum airspeed fo1 this operation has been about 30 knots. Once in the drop area, forward speed is reduced to zero and the net is permitted to stabilize as the aircraft makes a vertical descent until the chain line is approximately 50 feet above the water. At this time the signal is given to release the net. The trigger is moved from full power position to the momentary depolarizing position and the net is dropped into the water in a uniform circular pattern with the chain line sinking rapidly to the bottom. The still airborne frame is returned to the beach by the helicopter. For pursing, (Fig. 3), the tending vessel moves into a position upwind of the net and drops anchor. The anchor line is veered until the stern of the vessel is within 20 feet of the float line. A strain is taken on the lower pursing line parallel to the bottom by a hauling line. To keep it parallel, the hauling line is pulled through a ring on a deadman (Tom) positioned on the bay bottom. The bottom of the net is effectively drawn into a tight purse against the deadman. On previous test drops we have found that our pursing operation has been efficient enough to capture several tongue fish, Symphurus plagiusa (Linnaeus). The top pursing line is retrieved and the top of the net is easily pursed by hand. The closed bag is hoisted aboard and transported back to the laboratory where the specimens are removed for processing. Biological Aspects Calculation of sample size is made on a pounds per acre and g/m2 basis with the area of the device equalling about 1/ 40th of one acre ( 100.4 sq. m.). Table 1 shows the order of magnitude and species taken for the first series of drops made in Corpus Christi Bay. This device has the advantage of deep water sampling, unlimited mobility for unbiased sampling, and the complete and rapid isolation of a known sample area from an air­ Helicopter Borne Purse Net ~·· FIG. 2. Device airborne and enroute to drop area. borne vantage point. We have found the area to be somewhat variable in that there is a natural tendency for the net to constrict somewhat after release. The geometric shape remains reasonably constant but the 50 foot diameter is reduced to an average of 37 feet. In the drop position (chain line 50 feet above water), the helicopter is at an altitude of approximately 140 feet and the disturbance it may cause over the habitat by noise, downdraft, etc., is negligible. Unless the sun is directly overhead, all shadows are cast Helicopter Borne Purse Net Frc. 3a. :\let delivered, hauling line attached to bottom pursing line, and deadman ready to put o,·erboa rel. Frc. 3b. Pursing the bottom of !he net. NET-PURSED, TOP a BOTTOM, READY TO HAUL : ~---~--~~~. ...,,,.,..,.,,,,,.,,,,,,~~~="',__..,.,-,.-,,,......,,,. . =,...,,.,.,.,.,.;::, ,.::::,,.::::,... --•.-, .. -......,.,,.,.­ ABQ,A~Pc . .. ,.. ,,.,,,,...,c-.,,::.,.::::.,.,:;:,,:.,.....· .. ,.~,...-= Fie. 3c. Top and bottom of net pursed, deadman returned to the boat and net ready to haul aboard. well out of the drop zone. Normal wind action and the mirroring effect of the sun on the water surface renders the entire device invisible to subsurface organisms. The device is now considered operational and is being used to conduct a £tudy of Corpus Christi Bay. With modifications future applications may include: population sampling in the shallow Gulf up to 10 fathoms, and harvesting tightly schooling fishes like the menhaden and mullet. Aircraft observation of other schooling species is shown by Squire (1961) . One British organization is known to be considering helicopters to pull fishing trawls but they are not directly concerned with population sampling (Anon. 1962). Completely independent operation by a surface vessel towing a lighter than air delivery vehicle could be developed replacing the more expensive helicopter operation. Helicopter Borne Purse Net TABLE 1 Yield of fishes from the air delivery purse net by preserved weight per unit acre g/m' Sept. 41 Oct. 101 Dec. 19 Jan. 4 Feb. 19 Mar. 6 Leiostomus xanthurus 0.66 3.26 2.33 0.65 Micropogon undulatus Cynoscion arenarius Cynoscion nebulosus M ugil cephalus Brevoortia patronus Galeichthys felis Chloroscombrus chrysurus Anchoa hepsetus 4.01 0.39 0.72 6.57 0.09 11.4 12.65 6.07 0.34 16.'19 7.69 O.Ql Catch in g TOTALS g per m2 lbs per acre 509.0 5.07 44.8 1067.0 10.6 94.0 1378.0 13.7 121.6 1879.0 18.7 165.6 1725.0 17.2 152.0 771.8 7.7 68.0 1 These drops were made before the magnet suspension system was developed; frame was also dropped into water. Acknowledgments This study was made possible through the interest and cooperation of Rear Admiral L. J. Kirn, USN, the past Chief of the Air Advanced Training Command at Corpus Christi, Texas, and his successor Rear Admiral F. A. Brandley, USN. Participating heli­copter pilots were LCDR Jim Hamburg, USN; LCDR 0. E. Gercken, USN (also our present liaison officer) ; Lt. W. I. S. Easton, USNR; Lt. J. E. Woolum, USN; and Capt. Robert Bray, USA. During the initial development and subsequent drops, Wayne Flen­niken, Emilio Guerra, Reece Brown, Don Wilson, and Ray McKnight served as research assistants. We are also indebted to Herman Moore, Captain of the M/ V Lorene, and to Dr. B. J. Copeland for his unbiased observations and criticism of the drops. Literature Cited Anonymous. 1962. British suggest using helicopter for ocean trawling. Comm. Fish. Rev. 24(9): 109. Hellier, T. R. 1959. The drop-net quadrat, a new population sampling device. Puhl. Inst. Mar. Sci. Univ. Tex. 5(1958): 165-168. Hellier, T. R. 1962. Fish production and biomass studies in relation to photosynthesis in the Laguna Madre of Texas. Pub!. Inst. Mar. Sci. Univ. Tex. 8: 1-22. Hoese, H. D., and R. S. Jones. 1963. Seasonality of larger animals in a Texas turtle grass com­munity. Puhl. Inst. Mar. Sci. Univ. Tex. 9: 37-47. McFarland, W. N. 1963. Seasonal change in the number and biomass of fishes from an open coastal beach. Pub!. Inst. Mar. Sci. Univ. Tex. 9: 91-112. Squire, J. L., Jr. 1961. Aerial fish spotting. U.S. Comm. Fish. Rev. 23 (12): 1-7. Buried Pleistocene River Valleys in Aransas and Baffin Bays, Texas E. WILLIAM BEHRENS Institute of Marine Science, The University of Texas Port Aransas, Texas Abstract A sub-bottom echo-sounding survey with a sonoprobe showed the extent of buried Pleistocene valleys in Aransas and Baffin Bays. The form of Baffin Bay follows the buried valley more closely than do the forms of other estuarine bays. This might be explained by the particular set of hydro­graphic forces operating in Baffin Bay. However, similarly reflecting beds at different depths in different bays suggest that differential subsidence could also explain this observation. A single core in Aransas Bay combined with the sonoprobe data suggests a depositional history that is similar to the history of San Antonio Bay except for a period of river sedimentation in Aransas Bay. This event might also be explained by differential subsidence or, alternatively, by past changes in the drainage basins emptying into Aransas Bay and its tributaries. Introduction The form of the coastline of Texas is a result of present day processes acting upon physiography inherited from the Pleistocene. Perhaps the most notable of the inherited physical features are the river valleys which were eroded during periods of extensive continental glaciation and consequent low stands of sea level. This report is concerned with the relationship between two of these river valleys and the bays (Aransas Bay and Baffin Bay) which now occupy them (Fig. 1). Procedure The channels of the Pleistocene rivers that have been located in a few of the Texas hays were discovered chiefly by coring (e.g., Parker, 1959; Fagg, 1957). In the present study all subsurface data were collected with a sonoprobe on loan to the Institute of Marine Science from the Texas Game and Fish Commission. This instrument gives a continuous recording of echo-sounding reflections from subsurface horizons of contrast­ing density. For further description of this instrument see McClure, Nelson, and Huckabay (1958). The sonoprobe's chief advantage is that with it the time and effort involved in delineating a particular subsurface feature is about two orders of magnitude less than would be required by coring. The sonoprobe has two disadvantages: first, it gives no information on the composition of the sediment (this is not quite true; litho­logically different beds produce different types of reflections; but, as yet, there are in­sufficient data to allow interpretation of sedimentary parameters from echograms); sec­ond, the recording portion of the instrument must be calibrated to a single assumed speed of the emitted sound impulses. This assumed speed is the speed of sound in water -approximately 4800 feet per second. Insofar as the speed of sound increases when the impulses enter the sediment the sonoprobe results are inaccurate. Although no measure­ments of acoustic properties of the sediment involved were made, such measurements on Buried Pleistocene River Valleys in Aransas and Baffin Bays, Texas N s ca I e 0 I 0 20 30 40 ~0 WEST BA-:y nauti cal miles 1 Trnpolocios Boy BAY MEXICO FIG. 1. Index map of the Texas coast. similar, Recent, unconsolidated sediments indicate that the speed of sound in them gen­erally ranges from 4900 to 6000 feet per second (Shumway, 1958; Moore and Shumway, 1959). As a first approximation a correction to 5040 feet per second (1.536 km/sec) was made in the present study. Results Figs. 2 and 3 show the locations of the sonoprobe traverses in Baffin Bay and Aransas Bay respectively. Figs. 4, 5, and 9 are reproductions of the sonoprobe recordings along some of these traverses with the depths corrected as noted above. Buried Pleistocene River Valleys in Aransas and Baffin Bays, Texas FrG. 2. Baffin Bay, Texas. Light dashed lines show locations of sonoprobe traverses; shaded area shows extent of buried Pleistocene valleys; heavy dashed lines show probable axes of tr:butary streams. Discussion General. Texas bays are basically of two types. The first type is characteristically elongated parallel to the coast, and the form bears no apparent relationship to present­day river systems. Bays of this type are referred to herein as lagoons. Major lagoons of the Texas coast include Laguna Madre, Redfish Bay, Espiritu Santo Bay, lower Mata­gorda Bay, and West Bay. Some of the forms of the second type of bay reflect dendritic river patterns, and major streams usually enter the bay heads. The long axes of the>:e bays are generally perpendicular to the coast, although some are oblique or parallel to it. Major bays of this type include Nueces-Corpus Christi Bays, San Antonio Bay, Lavaca-Tres Palacios-central Matagorda Bays, and Trinity-Galveston Bays. Bays of this type are referred to herein as estuarine bays. Lagoons are considered to have originated simply as water impounded behind Recent barrier islands (Price, 1947; LeBlanc and Hodgson, 1959). Estuarine bays originated as river valleys deeply eroded during periods of continental glaciation and consequent lowered sea level and were subsequently flooded as the glaciers melted and sea level rose (Price, 193S, 1954) . Pleistocene river valleys alsr, may be buried beneath parts of some lagoons (Fisk, 1959), but the lagoons do not ewe their existence to these valleys as do the estuarine bays. Baffin Bay. Baffin Bay (including Alazan Bay, Cayo del Grullu, and Laguna Salada) has all the characteristics of an estuarine bay except that the associated streams are small and often dry. The form of Baffin Bay is actually closer to a river valley system than is the form of any of the other large estuarine bays; and the sonoprobe results show that this form parallels closely the underlying, buried valleys (Fig. 2) _The question arises, why has the form of this bay remained so close to that of the buried river valleys in which it originated? Three hypotheses are considered. Hypothesis L Baffin Bay is a relatively shallow basin which was invaded by the sea 10 Buried Pleistocene River VaUeys in Aransas and Baffin Bays, Texas Fie. 3. Aransas Bay, Texas. Light dashed lines show locations of sonoprobe traverses; shaded area shows extent of buried Pleistocene valley; heavy dashed lines show probable axes of tributary streams. later than were other estuarine bays. Thus waves and tidal currents have not had time to modify the shape of the basin. The sonoprobe records show that the valleys in Laguna Salada and Cayo de! Grullo are approximately 55 feet deep. (All depths are given in feet below sea level.) Therefore in lower Baffin Bay the valley bottom probably lies 60 to 80 feet below sea level. In San Antonio and Matagorda Bays valley depths of 83 feet and less than 80 feet, respectively, have been determined by coring (Shepard and Moore, Buried Pleistocene River Valleys in Aransas and Baffin Bays, Texas FIG. 4. Reproduction of echogram from Baffin Bay; see Figure 2 for location of the section. c' F':"""'------------------~seo level ·..................... "'1!!!!11!1!""!!~:1111111~11..~.... IQ depth in 20 feet 30 40 50 0 horizonlal scol• X 1000 ful D o' 10 20 30 40 50 FIG. 5. Reproduction of echograms from Baffin Bay; see Figure 2 for location of the sections. 1955; Fagg, 1957). This evidence suggests that the differences in valley depths are in­sufficient to account for differences in bay forms. Hypothesis 2. The interior forces which modify a bay's form are less effective in Baffin Bay than in other estaurine bays. Price (1947) has pointed out that the forms of tidal basins along the Texas coast appear to be in dynamic equilibrium with normal or interior forces such as tidal currents, waves, wind driven currents, gravitational settling of sediments, chemical precipitation, growth of bottom dwelling organisms, and the ef­fect of rainfall and wind on the immediate basin margins which extend above water level. There is little apparent difference between celestial tides in Baffin Bay and those measured at Corpus Christi and Rockport (Breuer, 1957; Collier and Hedgpeth, 1950). Tide data are scarce, however, and measurements of tidal currents, or indeed of any bot­tom currents, are nil. Sedimentation in hypersaline Baffin Bay certainly differs from sedimentation in the generally brackish-water estuarine bays to the north. However, Breuer (1957) cites evi­dence (e.g., oyster bearing middens at Indian camp sites) suggesting that until very recently conditions in Baffin Bay were quite similar to those in presently brackish es­tuarine bays. In fact, a pass to the Gulf may have been open until very recently in Baf­fin Bay's history (Price in Breuer 1957, p. 138-139). Buried Pleistocene River Valleys in Aransas and Baffin Bays, Texas Wave action is, perhaps, the most important interior force affecting bay shorelines. The writer is indebted to Dr. W. Armstrong Price for pointing out several aspects of wave action discussed in this section. It is well known that wave fronts are perpendicular to wind direction. It is also well known to coastal residents that the strongest winds com­monly blow from either the southeast or the northeast. The predominance of the south­east wind is apparent from weather bureau statistics (Fig. 6) . The effectiveness of these winds is apparent in the straightness of several northeast trending shorelines (Figs. 1, 2, and 3) . Strong northeast winds are not brought out in the wind rose probably because they are of relatively short duration usually accompanying cold fronts in the winter months. The air associated with these winds is cold, heavy, and usually wet, and the winds are often of gale force. Several northeast facing bay shores attest to the effective­ness of waves generated by these winds to straighten shorelines (Fig. 1). Fig. 7 shows that the fetches of these two dominant winds are generally less in Baffin Bay than in other Texas bays. Insofar as bays are enlarged as well as their shorelines straightened by this wave action the different orientation of Baffin Bay contributes to its relative lack of enlargement. In addition, the shores of Baffin Bay may be relatively difficult to erode. For example, the shore sediments have been cemented into beach rock at several places in Baffin Bay (personal communications from Dr. W. Armstrong Price of Corpus Christi and Mr. Donald W. Dalrymple of Rice Cniversity). Concerning the north shore of lower Baffin Bay Rusnak (1960, p. 167) states"... the relative wave strength is reduced by shoal water above a shallow platform consisting of dense, brown Pleistocene beach rock front· ing the shoreline." A similar ledge of this beach rock capped by serpulid reefs has prob­ably formed an effective hydrographic barrier across most of the mouth of Baffin Bay (personal communications from Dr. W. Armstrong Price of Corpus Christi and Mr. Donald W. Dalrymple of Rice University). Numerous rocky shoals within Baffin Bay (e.g., across the mouth of Alazan Bay) probably also serve to break up the fetch of winds and thus to diminish wave effectiveness. However, these rocky shoals might have had no N 14 8 3 13 15 46 FIG. 6. "Wind strength . . . at Corpus Christi. Data from United States Weather Bureau. Relative strength of wind (in percentage of all winds) derived from products of squares of average hourly Yelocities (1923-30 period) multiplied by average duration for each wind in percentage of time (1923-31) period," as developed by Price. (Price, 1933, Fig. 9, p. 933.) Buried Pleistocene River Valleys in Aransas and Baffin Bays, Texas GALVESTON ­TRINITY BAYS MATAGORDA BAY z SAN ANTONIO BAY 0 :0 .... :c ARANSAS BAY "'l> Cll .... COPANO BAY .., "' CORPUS BAY .... CHRISTI n :c c=~_____,I mo xi mum BAFFIN BAY -average ' I ' ' N 0 (J1 (J1 N miles 0 (J1 0 I I ' I GALVESTON ­TRINITY BAYS MATAGORDA BAY Cll SAN ANTONIO BAY 0 .... :c c: c=i ARANSAS BAY "'l> Cll .... c=i COPANO BAY .., "'-< CORPUS CHRISTI BAY n :c maximum BAFFIN BAY era 9 e Frc. 7. Maximum fetch lengths for northeast and southeast winds in major Texas bays. The maxi­mum fetch extends over a broad area in most bays and is thus nearly equal to the average; however in Baffin Bay maximum fetch lengths are located in long narrow arms of the bay, and average fetch lengths are considerably less. more effect than oyster reefs in the brackish estaurine bays to the north. For example, the southwest shore of Copano Bay shows considerable straightening normal to the north­east winds. However, three oyster reefs segment the bay by cutting directly across the fetch of this wind. In the absence of more detailed hydrographic information this hypothesis probably should be neither accepted nor rejected at this time. Hypothesis 3. Baffin Bay has remained essentially stable whereas other major estaurine bays have subsided to some extent since they were initially flooded. Subsidence of the coast of the northwest Gulf of Mexico has been noted by several workers (e.g., Russell and Howe, 1935; Price, 1947; Marmer, 1952) . Concerning the Mississippi delta region since the last glacial maximum Fisk and McFarlan ( 1954, p. 279) state "The continental margin has subsided during deposition, forming a trough-like depression which is lo­calized to the depositional area. This trough has been downwarped more than 350 feet near the present shoreline and more than 500 feet offshore on the continental shelf." This subsidence accounts for roughly 50% of the total section to the base of the Mis­sissippi trench. The sonoprobe records for Baffin Bay commonly show one or two strongly reflecting horizons at 24 to 32 feet (Figs. 4 and 5). Similar strongly reflecting beds in Aransas Buried Pleistocene River Valleys in Aransas and Baffin Bays, Texas Bay occur at depths of 47 and 54 feet, and in Corpus Christi Bay at depths of 60 to 61 feet. The similarity of their reflections suggests that these beds may represent a common event. If subsidence also accounts for about 50% of the sections in Aransas and Corpus Christi Bays but was essentially nil in Baffin Bay, then all of these beds would have been deposited at about the same depth (24-32 feet). This same subsidence could then ac­count for more widespread flooding and expansion of estaurine bays whose forms do not follow buried river channels so closely as does the form of Baffin Bay (Fig. 8). FrG. 8. Hypothetical development of estuarine bays. A-A': Pleistocene valley is filled with sedi­ment as sea level rises; wave erosion expands bay slightly beyond original valley walls; no subsi­dence. B-B': same history as in the A-A' sequence except subsidence has depressed valley walls resulting in a wider bay. Aransas Bay. Although Aransas Bay looks like a lagoon several small rivers feed it through Copano Bay and an estuarine bay (St. Charles Bay) enters it at the north end. Thus one might suspect that Aransas Bay actually had a compound origin, and a Pleis­tocene valley lies buried beneath it. The sonoprobe results show that this is, indeed, the case. Fig. 3 shows the areal extent of this buried valley and Fig. 9 shows a cross section of it. x x 10 20 30 40 >O 60 70 10 20 30 ~ 40 ::: •o 00 00 ~ 60 ,o ft . horizontal scale 70 Frc. 9. Reproduction of echogram from Aransas Bay; see Figure 3 for location of section. See text for descriptions of the samples numbered in the core. Shepard and Moore ( 1955, p. 1561-1562) describe a core from Aransas Bay which when correlated with the cross section shown in Fig. 9 suggests some of the detailed de­positional history of this bay. Shepard's and Moore's descriptions and interpretations of the samples numbered in Fig. 9 are summarized below. 1. " ... the high percentage of Foraminifera in the coarse fraction indicates the 'bay Buried Pleistocene River Valleys in Aransas and Baffin Bays, Texas no special influence' environment which is found also in the surface samples" (op. cit., p. 1561) . 2. Foraminifera and shells become scarce; gla~conite high, no echinoids; Forami· nifera and macro-organisms suggest bay environment but unlike present bays. 3. Sand down to 11.6%, silt up to 50.4%, Gulf Foraminifera, bay macro-organisms, both_ scarce; an enigma. 4. Foraminifera and shells abundant; "The presence of aggregates suggests the pos­sibility that the sediment is a land deposit" (op. cit., p. 1562). 5. Same as sample 4. 6. Same as samples 4 and 5 except slightly more sand. 7. Same as samples 4, 5, and 6 except slightly more aggregates. 8. Shells abundant, coarse fraction up to 69%, Foraminifera common; inlet en­vironment. 9. Coarse fraction up to 85.6%, Foraminifera scarce, grains rounded slightly less than in dune sand; barrier island flat. 10. Sand down to 3751c , abundant shells and Foraminifera of open Gulf and lower bay type, glauconite and echinoids suggest a connection with the Gulf. 11. Mixed Gulf and lower bay fauna, coarse fraction 36%, glauconite and echinoids scarce, relatively protected bay. In Fig. 10 the depositional history interpreted from these data is depicted and can be compared with the history of San Antonio Bay (Fig. 11) as interpreted by Parker (1959). River influenced estuarine sediments were encountered immediately above the Pleistocene in the ancient San Antonio river channel. These are overlain by sediments presumably deposited in a bay enclosed by a pre-existing high which acted as a barrier island and was located beneath the present barrier island (Parker, 1959). The base of the core in Aransas Bay appears to have penetrated to an equivalent horizon of en­closed bay sediments. Thus a pre-existing barrier ridge presumably also underlies St. Joseph Island. As sea level rose above this ridge open bay or sound conditions existed in both bays. These conditions prevailed in San Antonio Bay until the Recent barrier island grew and slowly created the enclosed bay and river influenced environments that exist there today (Parker, 1959). However, in Aransas Bay the open bay deposits are overlain by two strongly reflecting horizons which Shepard and Moore ( 1955) interpret as barrier flat and inlet deposits respectively. As such, these beds suggest a very near-by shoreline. The position of the 10 zo 30 40 ~ 00 ~ 00 .o 60 "­ llorho11t ol 1co l1 70 eo ~river influenced D barrier-inlet complex D ope n bo y inltt-influenced CJ enclosed boy inter-reef ~open boy or sound FIG. 10. Interpretation of depositional history of Aransas Bay. Buried Pleistocene River Valleys in Aransas and Baffin Bays, Texas 10 20 30 40 !50 60 ~ 70 80 90 FIG. 11. "Generalized interpretation of depositional history of Mesquite Bay and lower San An­tonio Bay, based on macro-fauna) evidence." Parker 0959, p. 2155, Fig. 3lb). Vertical lines represent cores. superjacent silty section relative to the river channel shown in the sonoprobe cross sec­tion (Fig. 9) clearly indicates that the silt represents flood plain deposits. Apparently the sea regressed relative to Aransas Bay at this time. Above the flood plain silts open bay deposits succeeded by the closed bay deposits which form the present bay bottom suggest flooding and subsequent enclosement of the bay hy a growing barrier island just as occurred in San Antonio Bay. If these interpretations are correct, the enigmatic sample (number 3) would represent a reworked flood plain deposit with Gulf and bay organisms mixed in by the transgressing sea. The question, what caused the sea to regress briefly from Aransas Bay while San An­tonio Bay remained open to the Gulf, invites speculation. If, as previously suggested, dif­ferential subsidence is indeed an affective agent, the different histories of the two bays could be explained by assuming that San Antonio Bay subsided below sea level at the time that Aransas Bay was receiYing fluvial sediments. Alternatively, a period of in­creased river discharge and consequent sedimentation in Aransas Bay might produce the same effect. Although there are insufficient geomorphic data to evaluate this hypothesis well, two facts suggesting its plausibility should be pointed out. First, the San Antonio River runs perilously close to the northern limit of the area which drains into Copano and Aransas Bays (Fig. 12). Second, St. Charles Bay is a fairly large, apparently es­tuarine bay with almost no drainage basin. The size of this bay may be due to the fact that it occupies part of a Pleistocene lake or lagoon which lay immediately behind the Live Oak bar or to erosion of a Pleistocene valley by a much larger river than now flows into the bay. Although there is no apparent abandoned interconnecting valley, the San Antonio River i;:, at present, prevented from draining into St. Charles Bay only by a very low drainage divide. Finally it should be mentioned that these two hypotheses are not mutually exclusive; that is, differential subsidence could have played a major or minor role in addition to fluctuation in river derived sediment. F1G. 12. Drainage basin of Copano, Aransas, and St. Charles Bays. Total drainage area lined; St. Charles Bay drainage area cross-hatched. Conclusions The amount of information obtained from a relatively small survey with a sub-bottom echo-sounder, the sonoprobe, shows that this instrument is a most efficient tool for study­ing the third dimension (depth) and thus the fourth dimension (time) of sedimentary units. This is especially true when sonoprobe results are combined with a small quantity of core data. Although the ob.:ervations made in this study have several possible explanations a single process, differential subsidence, may account for similar reflecting horizons oc­curring at different levels in various bays, different amounts of widening of estuarine bays and different details in the depositional histories of the bays. Literature Cited Breuer, J. P. 1957. An ecological survey of Baffin and Alazan Bays, Texas. Puhl. Inst. Mar. Sci. Univ. Tex. 4(2): 134-155. Collier, A., and J. W. Hedgpeth. 1950. An introduction to the hydrography of tidal waters of Texas. Puhl. Inst. Mar. Sci. Univ. Tex. 1(2): 121-194. Fagg, D. B. 1957. The Recent marine sediments and Pleistocene surface of Matagorda Bay, Texas. Trans. Gulf. Coast Assn. Geo!. Soc. 7: 119-133. Fisk, H. N. 1959. Padre Island and the Laguna Madre flats, coastal south Texas. Second Coastal Geog. Cong. Coastal Studies Inst. La. St. Univ. p. 103-151. Fisk, H. N., and E. McFarlan, 1r. 1955. Late quarternary deltaic deposits of the Mississippi River. Geo!. Soc. Amer. Spec. Pap. 62, p. 279-302. LeBlanc, R. J., and W. D. Hodgson. 1959. Origin and development of the Texas shoreline. Second Coastal Geog. Conf. Coastal Studies Inst. La. St. Univ. p. 57-101. Buried Pleistocene River Valleys in Aransas and Baffin Bays, Texas Marmer, H. A. 1952. Changes in sea level determined from tide observations. Proc. Second Conf. Coastal Eng., Engineering Foundation, Univ. of Calif., chapt. 6, p. 62--07. McClure, C. D., H. F. Nelson, and W. B. Huckabay. 1958. Marine sonoprobe system, new tool for geologic mapping. Bull. Amer. Assn. Petrol. Geo!. 42(4): 701-716. Moore, D. G., and G. Shumway. 1959. Sediment thickness and Physical properties, Pigeon Point Shelf, California. J. geophys. Res. 64(3): 367-374. Parker, R. H. 1959. Macro-invertebrate assemblages of Central Texas Coastal Bays and Laguna Madre. Bull. Amer. Assn. Petrol. Geo!. 43(9): 2100-2166. Price, W. A. 1933. Role of diastrophism in topography of Corpus Christi area. South Texas. Bull. Amer. Assn. Petrol. Geo!. 17(8): 907-962. Price, W. A. 1947. Equilibrium of form and forces in tidal basins of coast of Texas and Louisiana. Bull. Amer. Assn. Petrol. Geo!. 31(9): 1619-1663. Price, W. A. 1954. Shorelines and coasts of the Gulf of Mexico, p. 39-65, in Gulf of Mexico, Its Origin, Waters, and Marine Life. Fish Bull. U.S. 55(89): 39-65. Rusnak, G. A. 1960. Sediments of Laguna Madre, Texas, p. 153-196. In Recent Sediments North­west Gulf of Mexico. Amer. Assn. Petrol. Geo!. Symposium. Russell, R. J., and H. V. Howe. 1935. Cheniers of southwest Louisiana. Geogr. Rev. 25(3) : -149-461. Shepard, F. P., and D. G. Moore. 1955. Central Texas coast sedimentation: characteristics of sedi­mentary environment, recent history, and diagenesis. Bull. Amer. Assn. Petrol. Geo!. 39(8): 1463-1593. Shumway, George. 1958. Acoustic, geologic, and physical properties of a suite of arctic slope sedi­ments. (Abstr.) Trans. Amer. Geophys. Un. 39(3): 542-543. A Characteristic Diurnal Metabolic Pattern in Balanced Microcosms1 ROBERT J. BEYERS Institute of Marine Science, The University of Texas Port Aransas, Texas Abstract Data are presented on the diurnal pattern of metabolic rates of nine kinds of balanced aquatic microcosms including an oyster reef pond, two coral heads, balanced freshwater aquaria, a blue-green algal mat system, a brine microcosm, a microcosm at 51 degrees centigrade, a temporary pond system, and a green hydra. Net photosynthesis was maximal in the first half of the light period and nighttime respiration was maximal in the first half of the dark period. Similar patterns were noted in nature. Introduction The small size laboratory' ecosystem is rapidly becoming a fundamental tool in the development of comparative ecology. These artificial ecosystems have been termed microcosms (Odum and Hoskin, 1957), aquarium microcosms (Whittaker, 1961), microecosystems {Beyers, 1962a), experimental ecosystems (Beyers, 1962b) , carboy microcosms (McConnell, 1962), or laboratory-scale models (Pipes, 1962) . However, regardless of the name, such small systems can be used to compare ecosystems as to metabolic patterns, species composition, successional stages, and other theoretical con­cerns without the difficulties of replication, size, and ease of application of experimental techniques presented by natural ecosystems. For a number of years, Dr. Howard T. Odum, several co-workers, and the author have been using the microcosm approach for basic ecological studies carried on at the Insti­tute of Marine Science. In one seriea of studies (Beyers, 1962a), the author noted that the carbon dioxide rate of change curves from twelve freshwater benthic microcosms showed a fairly regular pattern. The nighttime respiration was at a maximum in the early evening after the lights were extinguished. The respiratory rate then dropped until the lights came on again the next morning. The net photosynthesis showed a similar pattern with production at a maximum immediately after the lights were turned on and with decreasing photosynthesis during the rest of the day. Fig. 1 shows an average of 100 carbon dioxide diurnal rate of change curves in the benthic systems and demonstrates a characteristic shape. To investigate the generality of the pattern, metabolic measure­ments were made on eight different kinds of microcosms. Materials and Methods The diurnal course of metabolism in all the artificial ecosystems was followed using the 1 From a symposium "Space Biology: Ecological Aspects" at the 1962 meeting of the American Institute of Biological Sciences, Corvallis, Oregon. These studies were aided by the National Science Foundation through grant NSF G-13160 on Ecological Microcosms and NSF G-8902 on the Bio­geology of Reefs. (See Am. Biol. Teacher. Vol. 25 No. 6 and 7. 1%3) . diurnal rate of change concept of Odum, 1956 and Odum and Hoskin, 1958. The advan­tage of this free water method, as opposed to any of the more conventional bottle meth­ods, such as light and dark bottles or the carbon fourteen method, is that the data are presented in such a way that hour by hour changes in the rate of community photo­synthesis or respiration are readily apparent. Total community metabolism during either the light or dark period can easily be computed for comparison with the older methods. The method used was that of Beyers, 1962a, in which changes in concentration of total carbon dioxide were measured using the relationship between dissolved carbon dioxide and pH (Beyers and Odum, 1959, 1960; Beyers et al., 1963). This method in­volves the use of recording pH meters to determine the diurnal variation in the pH of the microcosm water. A sample of water from the ecosystem is bubbled with nitrogen or any other inert, carbon dioxide-free gas to raise the pH. The sample is then titrated with distilled water saturated with carbon dioxide under approximately one atmosphere pres­sure using a tonometer burette. This procedure is essentially a titration with gaseous carbon dioxide using distilled water as a carrier, and it establishes the relationship be­tween pH and total carbon dioxide. If this relationship is known, any change in pH can be translated into change in concentration of total carbon dioxide. The titration curve and the diurnal pH changes are the data from which the diurnal rate of change curve is constructed. The accuracy of this method varies with the chemical composition of the water but is generally± 0.01 millimole carbon dioxide per liter per twelve hours (Beyers, l 962a; Beyers, et al. 1963) . The microcosms were under two different light and temperature regimes. Six differ­ent types of systems were in a constant temperature room under controlled temperature and a twelve hour photoperiod with constant artificial light (Fig. 1-3) . These six systems were: 1) The tweh-e freshwater benthic systems investigated by Beyers, 1962a and b. 2) A marine algal mat containing Lyngbya, Oscillatoria, Desulfovibrio, and purple sulfur bacteria. This work was done by Mr. Neal Armstrong of the Institute of Marine Science. 3) A microcosm taken from the Mimbres Hot Springs, Mimbres, New Mexico, by Dr. Austin Phelps of the University of Texas, and kept in a constant temperature bath at 51 ° C. This community contained Phormidium, Oscillawria, and Anabaena. 4) A temporary pond type microcosm containing material from the vernal ponds on top of Enchanted Rock, Llano, Texas, and measured midway between filling and dry­ ing. The principal organisms in this system were cladocera, ostracoda, and small green flagellates. 5) A brine microcosm taken from the Salina Fortuna salt evaporating ponds near La Parguera, Puerto Rico, and containing Artemia and Dunaliella. 6) Twenty Chlorohydra of the strain of Eakin, 1961, in 0.6 ml of artificial medium. The other three systems (Fig. 4) were under natural light and varying temperatures in yarious outdoor situations. These three systems were: 1) A concrete pond containing an artificial oyster reef. The principal members of this community were Crassostrea, Brachidontes, Menippe, gammarids and a small green flagellate. This microcosm was initially seeded from Aransas and Capano Bays, Texas. 2) A small isolated coral head (Millepora) placed in a transparent chamber and cooled with running sea water. 3) Two small isolated coral heads (Po rites) under similar circumstances. In these latter two cases, the coral heads were taken from the fringing reef around Magueyes Island, Puerto Rico. This work was done at the Institute of Marine Biology, University of Puerto Rico, La Parguera, P. R. In the coral heads as well as in the Chlorohydra, the community consisted of the coelenterates and their symbiotic algae. Table 1 gives a summary of the light, temperature and salinity conditions under which the various experiments were carried out. The volumes of the microcosms and a partial community composition are also shown in the table. Results and Discussion Metabolic Parameters. In considering the overall metabolism of a closed ecosystem, two similar but opposite processes are of importance. They are total respiration and gross photosynthesis. Total respiration is the entire heterotrophic activity of all the or­ganisms, both animals and plants, in the system while gross photosynthesis is the entire autotrophic effort of all the primary producers in the community. Neither of these quan­tities are measurable in the light because they are essentially the same net chemical change proceeding simultaneously in both directions. During the day only the excess of gross photosynthesis over daytime respiration can be measured. This excess is termed net photosynthesis ( P n) . In the dark only respiration takes place. Therefore, it is possible to measure it. How­ever, on a twenty-four hour basis the nighttime respiration (Rni) is not the total respira­tion of the system. The respiration which takes place during the light period does not figure in the nighttime respiration. Hence we are left with two measurable quantities, net photosynthesis and nighttime respiration. The values for these two quantities for the nine different types of microecosystem studies are shown in Table l. The figures are ex­pressed as millimoles carbon dioxide ( ± 0.01) absorbed or liberated per liter of micro­cosm water per twelve hour light or dark period. In a balanced steady state system, if no export or import occurs, the ratio of net pro­duction to nighttime respiration ( P n/ Rn i) must be unity. This situation is necessitated by the fact that net photosynthesis, which is the excess of daytime photosynthesis over daytime respiration must account for the organic matter and oxygen consumed by night­time respiration. If some temporary happening should disturb this ratio in such a man­ner that it becomes greater or lesser than unity an increase or reduction of the system's biomass through growth or s~arvation will take place and the ratio will tend to return to unity. The net photosynthesis to nighttime respiration ratios in these microcosms were close to one (Table 1), the average being around 1.1. It can therefore be assumed that these systems were very close to being balanced. Metabolic Pattern. In an attempt to determine whether the metabolic pattern shown by the benthic systems (Fig. 1) was of a general nature, several other microcosms of various types were measured under similar conditions. They were the algal mat com­munity, hot spring community, the temporary pond community and the brine commu­nity. Representative curves of these four microcosms are given in Fig. 2. The same type of metabolism is shown by all four systems. The most extreme cases are in the hot spring ::i:.. TABLE 1 ~ Resume of conditions and total rates of net photosynthesis and nighttime respiration for eight types of aquatic microcosms ~ ;::... ..., ~ (') Ncl Nighttime photosynthesis respiration ib" ..., Parli ul mMC02/ L mMC02/L i;:· Type of Light in Tempera lure community Salinity Volume in per 12 hr. per 12hr. ""' microcosm foot candles ·c composition in %o liters (± 0.01) (± 0.01) P./ Rnl i:; · .... ~ . Algal mat microcosm 1000 constant 14 Desulfovibrio, Lyngbya, ;:: Oscillatoria, purple ..., sulfur bacteria 34 0.166 0.80 0.69 1.16 l 51° microcosm 784 constant 51 Phormidium, Oscillatoria, a::: Anabaena 0 4.020 0.28 0.28 LOO "' ~ 0­ Temporary pond microcosm 850 constant 22 Cladocera, ostracoda, small ~ ..... green flagellates 0 4.000 0.17 0.11 l.47 (') '"ti ~ Brine microcosm 467 constant 23 Artemia, Dunaliella 188 2.030 0.29 0.26 l.12 ::: Mean of benthic systems 1000 constant 23 Valli.meria, Oedogonium, ;;"' Sutroa, Physa 0 3.000 0.20 0.17 l.18 ;:;· Green hydra 1000 constant 23 Chlorohydra and symbiotic algae 0 0.0006 1.12 l.14 0.98 O:l ~ ...... Oyster pond 0-8200 30-35 Oyster reef fauna and small ~ ~ green flagellates 18 5930.000 0.19 0.13 l.46 (') "' ~ Coral (Millepora) 0-8300 26-29 M illepora and symbionts 32 0.400 0.44 0.42 1.03 a::: ~· Coral (Po rites) ..., # 1 0-8300 26-29 Porites and symbionts 34 0.385 0.49 0.38 l.28 c #2 0-8300 26-29 Porites and symbionts 32 0.305 0.31 0.37 0.87 8 "' s "' 19 7 13 19 TIME Fie. 1. Diurnal rates of carbon dioxide uptake and release during net photosynthesis and night­time respiration in twelve benthic freshwater microcosms. This curve is the mean of one hundred curves. (Redrawn from Beyers, 1962a.) (51° C. microcosm) and brine microcosms which are also the simplest communities. However, the algal mat and the temporary pond also show decreasing metabolism as either the day or night progresses. These latter two microcosms are much more complex systems in terms of species variety than the hot spring or brine microcosms. Among the simplest of ecosystems is the one represented by the green hydra (Chloro­hydra). It consists of the hydra and its symbiotic algae. When measurements of Chloro­hydra metabolism are treated in the same way as metabolic measurements of other eco­systems the same pattern becomes evident (Fig. 3) . However, in this case the maximum photosynthesis occurs within two hours after lights on or lights off. Fig. 4 demonstrates the shape of the carbon dioxide diurnal rate of change curves under a natural bell-shaped light curve. All of the curves in Figs. 1-3 were taken under a square-shaped curve of artificial light. In these outdoor systems, the same type of res­piratory pattern is indicated. However, the photosynthetic pattern is affected by the changing light. Maximum net photosynthesis usually occurs in the morning even though the light reaches its maximum around noon. There is also an excess of respiration over photosynthesis in the late afternoon, resulting in a negative rate of net photosynthesis. The photosynthetic pattern under constant illumination corresponds closely to the re­sults of Doty and Oguri, 1957; Yentsch and Ryther, 1957; and McAllister, 1963 for ma­rine planktonic systems. The pattern under natural illumination is corroborated by Ver­duin, 1957, for the planktonic systems in Western Lake Erie, by Copeland, Butler, and Shelton, 1961, for Theta Pond, Oklahoma, and by Copeland and Dorris, 1962, for oil re­ A Characteristic Diurnal, Meabolic Pattern in Bdanced Microcosms 8 14 20 8 8 14 20 2 8 ' 0 "' u ~ LIGHTS ON LIGHTS OFF LIGHTS ON LIGHTS OFF + E+ TEMPORARY POND 0.12 0.12 0.12 0.12 9 9 9 3 9 TIM E FIG. 2. Diurnal rates of carbon dioxide uptake and release during net photosynthesis and night­time respiration in a marine algal mat microcosm, a hot spring microcosm, a temporary pond microcosm, and brine microcosm. finery effluent holding ponds. The decreasing nighttime respiratory rate in natural aquatic systems is demonstrated by Jackson and McFadden, 1954, for Sanctuary Lake and by Park, Hood and Odum, 1958, in four out of seven of their carbon dioxide diurnal rate of change curves for several Texas bays. It must be remembered when considering the photosynthetic pattern that these curves (Fig. 1-3) represent net photosynthesis. That is, they are graphs of the difference be­tween gross photosynthesis and daytime respiration. Several hypotheses may be postu­lated to explain the shape of these curves. First, gross photosynthesis may be constant under constant illumination while daytime respiration increases during the day. In fact, + LIGHTS ON 8 HYDRA 4 0: I ' <[ 0: Cl >­ I ' I '° 0 x C\J 0 4 u :::? E 8 12 19 7 TIME FIG. 3. Diurnal rates of carbon dioxide uptake and release during net photosynthesis and night­time respiration in Chlorohydra; based on twenty specimens in 0.6 ml of water, results expressed as metabolism per hydra. daytime respiration could increase to a level almost equalling gross photosynthesis and thus account for curves of the shape of the brine microcosm or the 51° microcosm (Fig. 2) or it could exceed gross photosynthesis in the late afternoon, accounting for the shapes of the curves in Fig. 4. Second, the gross photosynthesis may decrease during the day while the daytime respiration remains constant, or third, the daytime respiration may increase while the gross photosynthesis decreases during the course of the light period. Since gross photosynthesis and daytime respiration occur simultaneously, it is not possible at present to test these three hypotheses to determine which is correct. How­ 13 19 A Characteristic Diurnal Meabolic Pattern in Balanced Microcosms FIG. 4. Diurnal rates of carbon dioxide uptake and release during net photosynthesis and night· time respiration in an oyster pond microcosm and in three small, isolated coral heads. ever, it can be demonstrated that nighttime respiration does not remain constant ( Fig. 1-4) and since nighttime respiration is not static there is no reason to assume that day­time respiration stays constant. This situation casts doubt on the validity of the second hypothesis mentioned above. Further discussion regarding the shape of these curves in relation to labile fuel and oxygen, increasing carbon dioxide concentration, and inherent metabolic rhythms may be found elsewhere (Beyers, 1962a). The similarity between microcosm metabolism curves under artificial light and electrical analogue circuits set up as theoretical models relating metabolic rates to storage accumulations has been pointed out by Odum, Beyers, and Armstrong, 1963. The data obtained in the present study are reported here because A Characteristic Diurnal Meabolic Pattern in Balanced Microcosms they extend the earlier observations on the changing metabolic rates in larger aquatic ecosystems. Acknowledgments I would like to thank Dr. Juan A. Rivero and Dr. John Randall for research facilities at the Institute of Marine Biology, University of Puerto Rico, Mayaguez. Some of the data used in this study were obtained by Mr. Neal Armstrong and Mr. Bill Gillespie. Dr. Austin Phelps of the University of Texas collected the material for the hot spring micro­cosm. Drawings by Mr. Bill Gillespie. Literature Cited Beyers, Robert J. 1962a. The metabolism of twelve aquatic laboratory microecosystems. Ph.D. Thesis. Univ. of Texas (Order No. 62-2533) 190 p. Univ. Microfilms. Ann Arbor, Mich. (Dissertation Abstr. 23: 359.) Beyers, Robert J. 1962b. Relationship between temperature and the metabolism of experimental ecosystems. Science 136: 980--982. Beyers, Robert J., and Howard T. Odum. 1959. The use of carbon dioxide to construct pH curves for the measurement of productivity. Limnol. & Oceanogr. 4: 499-502. Beyers, Robert J., and Howard T. Odum. 1960. Differential titration with strong acids or bases vs. C02 water for productivity studies. Limnol. & Oceanogr. 5: 228-230. Beyers, Robert J., James L. Larimer, Howard T. Odum, Richard B. Parker, and Neal E. Armstrong. 1963. Directions for the determination of changes in carbon dioxide concentration from changes in pH. Puhl. Inst. Mar. Sci. Univ. Tex. 9: 454489. Copeland, B. J ., John L. Butler, and William L. Shelton. 1961. Photosynthetic productivity in a small pond. Proc. Okla. Acad. Sci. 42 : 22-26. Copeland, B. J., and Troy C. Dorris. 1962. Photosynthetic productivity in oil refinery effluent holding-ponds. J. Water Pollution Contr. Fed. 34: 1104--1111. Doty, J\laxwell S., and Mikihiko Oguri. 1957. Evidence for a photosynthetic daily periodicity. Limnol. & Oceanogr. 2: 37--40. Eakin, Robert E. 1961. Studies on chemical inhibition of regeneration in hydra. In Lenhoff, Howard M. and W. Farnsworth Loomis, The biology of the hydra and of some other coelenterates, liniv. of Miami Press, Coral Gables, Fla. Jackson, Daniel F., and James McFadden. 1954. Phytoplankton photosynthesis in Sanctuary Lake, Pymatuning Reservoir. Ecology 35: 1--4. McAllister, C. D. 1963. Measurements of diurnal variation in producti,·ity at ocean station '·P." Limnol. & Oceanogr. 8: 289-291. :\lcConnel, William J. 1962. Productivity relations in carboy microcosms. Limnol. & Oceanogr. 7: 335-343. Odum, Howard T. 1956. Primary production in flowing waters. Limnol & Oceanogr. l: 102-117. Odum, Howard T., and Charles :'\L Hoskin. 1957. Metabolism of a laboratory stream microcosm. Puhl. Inst. :'\lar. Sci. Univ. Tex. 4: 115-133. Odum, Howard T., and Charles M. Hoskin. 1958. Comparative studies of the metabolism of marine water. Puhl. Inst. Mar. Sci. Univ. Tex. 5: 16--46. Odum, Howard T., Robert ]. Beyers, and Neal E. ·Armstrong. 1963. Consequences of small storage capacity in nanoplankton pertinent to measurement of primary production in tropical waters. ]. :'liar. Res. 21: 191-198. Park, Kilho, Donald W. Hood, and Howard T. Odum. 1958. Diurnal pH rnriation in Texas Bays, and its application to primary production estimation. Puhl. Inst. Mar. Sci. Univ. Tex. 5: 47-64. Pipes, Wesley 0. 1962. pH variation and BOD removal in stabilization ponds. ]. Water Pollution Contr. Fed. 34: 1140--1150. Verduin, ]. 1951. Daytime variations in phytoplankton photosynthesis. Limnol. & Oceanogr. 2: 333-336. Whittaker, R. H. 1961. Experiments with radiophosphorus tracer in aquarium microcosms. Ecol. Monogr. 31: 151-188. Yentsch, C. S., and J. H. Ryther. 1957. Short term variations in phytoplankton chlorophyll and their significance. Limnol. & Oceanogr. 2: 140--142. Cobalt, Iron, and Manganese in a Texas Bay1 PATRICK L. PARKER, ANN GIBBS, AND ROBERT LAWLER Institute of Marine Science, The University of Texas Port Aransas, Texas Abstract The concentrations of cobalt, iron and manganese were determined in the water, sediments, under­water plants and animals predominating in the grass flats of Redfish Bay, a shallow marine estuary near Port Aransas, Texas. All three elements were greatly concentrated in sediment and organisms with respect to sea water. The concentrations were multiplied by estimates of dry weight of the principal components per square meter of bay to obtain an inventory of the grass flat. The plant Diplanthera wrightii is outstanding in that it accounts for much of the inventory of all three ele­ments in the community (2.3 mg/m2 Co, 627 mg/m2 Mn and 422 /mgm2 Fe). All chemical deter­minations were spectrophotometric. An appropriate gamma emitting radioisotope of each element w~s used to check the chemical procedure and to correct for chemical yield. A new method for the removal of manganese and cobalt from sea water by lanthanum hydroxide precipitation was developed. veloped. Introduction The concentration of zinc in sea water, sediment and a variety of marine organisms as well as the zinc inventory for Redfish Bay were reported by Parker (1962). The pres­ent work extends this study of trace elements to include cobalt, iron and maganese. All four elements are of biological importance in the sea yet are present in only trace quan­tities. Since the organisms living in the bay require several thousand times more trace ele­ments than is contained in the water column, some mechanism must be available to return the trace element removed by dead organisms to the system. It is very probable that the concentration of some trace metals in the bay water and perhaps in the sediment are a function of the rate of removal by the organisms and rates of return from the dead organ­isms, especially' since sea water is undersaturated with respect to insoluble compounds of several trace metals (for example zinc and cobalt) that might form from the ions nor­mally present in aerated sea water (Krauskopf, 1956). It was felt that knowledge of the distribution of these trace elements in the various phases of a typical marine estuary would, besides pointing up some interesting facts in the comparative biochemistry of the elements studied, serve as a base for further studies of the rate of removal and return of trace elements. In the course of this work it has been possible to apply known methods of chemical analysis to marine samples and to develop some new methods. Experimental Methods The methods of determination for all trace elements are essentially those described by Sandell (1959) and are based on spectrophotometry. For this reason only a very brief outline will be given. Where improvements have been made, as in the use of lanthanum hydroxide to concentrate cobalt and manganese from large volumes of sea water and 1 Supported by the United States Atomic Energy Commission through Contract No. AT(4~1) 2580. the use of radioactive tracers for keeping up with the chemical yield, more detail is given. All biological materials were decomposed by ashing in a porcelain crucible at 500° C. All water samples were collected and filtered ( 0.45 micron) just before analysis. Cobalt. Water rnmples necessarily had to be large; 4.5 liters were taken for each de­termination. After millipore-filtering a known quantity of Co60 was added to check the procedure and correct for losses. One hundred milligrams of LaCl3 and enough ammonia gas to cause lanthanum hydroxide to precipitate were added-the La (OH) 3 precipitation was repeated if the yield was less than 70%. The cobalt carried by the lanthanum was purified by the following procedure prior to determination. The hydroxide was dis­solved in a minimum of 1 :3 nitric acid and evaporated to near dryness on a steam bath. Nitric acid was added until the solution was clear. Sodium citrate ( 50% ) was added to give a pH of 3-4, using methyl orange as an indicator. Five ml of a 1 % w / v solution of l-nitroso-2-naphthol were added and the solution was allowed to stand for 15-20 minutes with occasional shaking. The cobalt complex was extracted into chloroform and washed with 1 :99 HCI. The chloroform extracts were evaporated to dryness on a steam bath and 1:1 HN0.3 and sodium sulfate were added to oxidize organic matter. Nitric acid was added until the sample was colorless. The cobalt was then determined in this material by the nitroso-R-salt described by Sandell (1959), using citrate-phosphate-borate buffer. The optical density was measured at 530 millimicrons using a Beckman Model B spec­trophotometer. Biological samples were ashed and the ash taken up in 1:1 nitric acid. After evapora­tion to dryness on a steam bath 25 ml of 1 :49 H3P04 was added if the sample was tissue or 25 ml of H20 if the sample contained bone. Sodium citrate was then added and the purification procedure and determination carried out as in the sea water samples. Sediment samples were digested in concentrated nitric acid containing a few ml of perchloric acid at boiling temperature for several hours. The acids were fumed off and the residue leached with 0.1 N HCI. Sodium citrate was added to the solution and the purification-determination procedure described above followed. Cobalt is ve;-y low in most samples so that care must be taken and blanks run with each series of determinations. Iron. Iron determinations were carried out using bathophenanthroline (4,7-diphenyl­1,10-phenantholine) following the procedure given by Sandell ( 1959). Iron in sea water samples was measured directly without further concentration (Lewis and Goldberg, 1954). Biological and sediment samples were decomposed with nitric-perchloric acid mixtures. Manganese. The permaganate color method was used to determine manganese (San­dell, 1959). Since it is not a very sensitive method, it was difficult to apply to sea water analysis. Nevertheless, since manganese was present in a high concentration in the or­ganisms, the results were satisfactory. Manganese with added Mn-54 tracer was concen­trated from several liters of sea water by lanthanum hydroxide precipitation as described for cobalt. Biological samples were ashed prior to determination. Results and Discussion Samples collected mostly from the turtle grass beds of Redfish Bay located near the Institute of Marine Science were analyzed for cobalt, iron, and maganese using the meth­ods described. Results for the biological and sediment samples are reported on a dry weight (110° CJ basis. These results are given in Table 1. The sea water values may be compared to data in the literature. Thus the range of values found for Co in the bay and beach waters around the Institute, 0.34 to 0.9, are similar to those reported by Ishibashi (1953), 0.38 to 0.67, and Black and Mitchell (1952), 0.3, where all values are in µ.g/liter. The bays around the Institute are much richer in both soluble (mean 30) and particulate (mean 200) iron (as defined by 0.45 micron millipore filtration), than are the w~ters of the North Pacific for which Lewis and Goldberg (1954) report a mean of 3.4 for soluble and 4.5 for particulate; all values in µ.g/liter. This is probably due to run­off and to stirring of the sediments by the wind. Manganese in Redfish Bay ranged be­tween 5 and 15 µ.g/ liter, which compares well with the values of 4.5 and 6.2 determined by activation analysis (Rona, Hood, Muse, and Buglio, 1962). The three elements did not show a relation between trace element concentration and salinity. From this it is concluded that processes other than evaporation and rainfall control the concentration of these elements in the bays. TABLE 1 Summary of chemical analyses Sample Co ppm Fe ppm Mo ppm Local bay watersl Redfish Bay sediment (5) 0.34-.9 0.4 (15) 5-78 1000 (3) 5-15 92 Grass, T halassia testudinum root 0.5 366 14 blade 0.34 279 173 Grass, Diplanthera wrightii Mullet, Mugil cephalus Pinfish, Lagodon rhomboides 4.0 0.5 0.6 735 178 48 llOO 18 24 Fish, M enidia sp. 0.6 160 20 Brown shrimp, Penaeus aztecus Grass shrimp, Palemonetes sp. 0.4 2. 75 285 10 26 Crab, Callinectes sapidus 0.3 166 42 Jellyfish, Physalia 1. 1 The waler concentrations are in parts per billion. The number in parenthesis gives the number of samples between the ranges given. Table 1 shows that all the organisms are greatly enriched in all three of the trace metals compared to sea water. This is the usual observation for trace elements in marine organisms (Fukai and Meinke, 1959). The exact significance of such concentration fac­to1:s is not known. The amount of trace metal in a given organism must be related ·to specific biochemical needs of the organism. But to understand the requirements of even one organism for one metal is a major problem which is beyond the scope of this paper. The value of data such as Table 1 is to point out the comparative behavior of different organisms toward different elements. For example, it is interesting that the plant Dip­lanthera wrightii contains more Co, Fe and Mn than any other organism studied. The relatively high cobalt content of the grass shrimp, Palemonetes sp., suggests that this easily grown and very abundant animal deserves further study. The inventory of Co, Fe and Mn given in Table 2 was the main reason for the present study. Quantitative knowledge of the distribution of these representative trace metals gives some insight into the behavior of these elements in a bay. Similar data has been published for zinc (Parker, 1962). Table 2 indicates that the amount of trace element held in the water column is negligible compared to that held in the organisms. Thus, for TABLE 2 Cobalt, iron and manganese inventory for a grass flat Dry weight1 Co Fe Mn Sample Description g/m' mg/m2 mg/m2 mg/m2 Bay water Sediment 1 m depth per cm depth 1 x 106 1 x 104 0.5 4.0 30 1 x 104 5 920 Thalassia roots summer crop 2800 1.4 1 x 103 39 blades 200 0.o7 74 34 Diplanthera summer crop 568 2.3 422 627 Mullet max biomass 2.3 1 x 10-3 0.4 4 min biomass 0.06 3 x 10-5 1 x 10-2 1 x 10-3 Pinfish avg biomass avg biomass 0.6 0.'18 3 x 10­4 1 x l0­4 1 x 10-1 9 x 10-3 1 x 10­2 4 x 10-3 Crab max biomass LS 5 x 10-4 3 x 10-1 6 x 10-2 Brown shrimp max biomass 0.07 3 x 10-5 5 x 10-3 7 x 10-4 1 Dry weight ,·alues for animals were taken from Hellier (1962), others were measured. this system the function of water must be one of transport, not of supply. The inventory shows that the amount of metal in the biosphere (plants and animals) is almost the same as that in the top cm2 of the sediment for Zn, Co, Fe and Mn. This suggests that the cen­tral problem in the biogeochemistry of these elements in this bay is the rate of movement from sediment to biosphere. It is especially important to have some estimate as to how much of the sediment, measured from the water sediment interface down, is involved in the cycle. A few measurements of the rate of movement of radioactive tracer into the sediment were made to get some feeling for this. Small cores of sediment with overlying water column were brought to the laboratory, tracer added, and the water stirred slightly by a bubble tube. There was a smooth loss of tracer from the water in all cases, with a half­time of a few hours. However, when the cores were frozen and sliced, it was found that the tracer had only penetrated the sediment 0.5 to 1.5 cm in 10 days. These preliminary results suggest that only the top few cm are important in the day-to-day cycle of these elements. It appears that a fine balance of these four elements is maintained between the plants and animals of the grass flat and the sediment. Since the turnover of carbon in the sys­tem is known to be large (Odum and Wilrnn, 1962) it is probable that there is a fairly rapid turnover of these elements. Since the amount of trace metal used by the system appears to be about the same as that available to it, depletion in trace metal cannot be ruled out as a factor in the productivity of the grass flat. Literature Cited Black, W. A. P., and R. L. Mitchell. 1952. Trace elements in the common brown algae and in sea water. J. Mar. Biol. Assn. U. K. 30: 575-584. Fukai, R., and W. W Meinke 1959. Trace analysis of marine organisms: a comparison of activation analysis and conventional methods. Limnol. & Oceanogr. 4: 398-408. Hellier, T. R. 1962. Fish production and biomass studies in relation to photosynthesis in the Laguna Madre of Texas. Puhl. Inst. Mar. Sci. Univ. Tex. 8: 1-22. Ishibashi, M. 1953. Studies on minute elements in sea-water. Rec. Oceanogr. wks. Jap. 1(1): 88-92. Krauskopf, K. B. 1956. Factors controlling the concentrations of thirteen rare metals in sea-water. Geochim. et cosmoch. Acta 9: 1-32. Lewis, G. J., and E. D. Goldberg. 1954. Iron in marine waters. J. Mar. Res. 13: 183-lSi. Odum, H. T., and R. F. Wilson. 1962. Further studies on reaeration and metabolism of Texas Bays, 1958-1960. Puhl. Inst. Mar. Sci. Univ. Tex. 8: 23-55. Parker, P. L. 1962. Zinc in a Texas Bay. Puhl. Inst. Mar. Sci. Univ. Tex. 8: 75-79. Rona, E., Donald H. Hood, Lowell Muse, and Benjamin Buglio. 1962. Activation analysis of manganese and zinc in seawater. Limnol. & Ocean-100 2 TOTAL CATCH -o­ 100 SEA LEVEL --• ·­ 50 " .'" ~ u ~ w " > I w ~ d w ~ FrG. 2. Total biomass (excluding larger species) correlated with bay water level at time of sample. 100 gms = 0.85 gms/m2 in all graphs. in the total biomass curves (Fig. 2) because they were inadequately sampled. Annual totals for both Opsanus beta and Mugil cephalus were 0.22 gm/m2 • One of these, 0. beta, actively sought the bases of the quadrat piling. Results The results of the annual cycle of sampling are given in the biomass graphs of Figs. 2-8 and in Table 1. Total catch, without the forementioned exceptions, is compared with bay water level at time of sampling (Fig. 2). The components of this catch are discussed in the following paragraphs. FrG. 3. Correlation of biomass of two species with temperatures at time of sample. JF MAM JJASO ND FrG. 4. Catch of pink shrimp, Penaeus duo­ rarum. 300 200 30 100 10 Seasonality of Larger Animals in a Texas Turtle Grass Community PINK SHRIMP Penaeus duorarum was the characteristic large Redfish Bay invertebrate. It was the only penaeid shrimp taken from the bay. This is amazing habitat specificity in view of the abundance of related P. aztecus in adjacent bays (Gunter, 1950, and others). A pop· ulation peak was reached on May 4, after the sudden appearance of large numbers of small shrimp in late March (Figs. 4, 9). Large juveniles and sub·adults disappeared in June, which is when large numbers of migrating pink shrimp have been caught in the inlet at Port Aransas in some years. During the hot summer months few shrimp were taken, but in October and November catches rose somewhat. Shrimp were scarce in winter but very small juveniles were taken as late as December 27. Smallest individuals (20--30 mm) were in the catch by early March, and continued to appear through mid-May. Except for a small amount in July, little or no recruitment occurred from early June until well into August. A second wave of young entered in late August through late November. The large peak reached in May £eems to be from growth of the largest influx of young in early April. Emigration of this group in late May and June left a smaller population from the small May recruitment. By June, recruitment stopped and nearly all shrimp soon reached emigration size (over 60 mm) leaving few to remain during the severe summer. The immigration of post-larval pinfish similarly stopped long before severe conditions began in July. Some mechanism seems to stop recruitment early preventing high densities when severe conditions begin. Since P. duorarum recruitment was constant, tracing size groups was difficult but ap­parently shrimp under 30 mm in March reached 65-75 mm by early May, and those under 30 mm in late August reached the same size by mid-October. These data suggest a growth rate close to 1 mm a day, below that Williams (1955) reported for North Caro­lina P. duorarum. Two-thirds of the Texas pink shrimp production comes from the Gulf opposite Redfish Bay (Gunter, 1962), one of the largest Thalassia communities on the Texas coast. Other small Thalassia communities occur in Aransas, Corpus Christi, and West Bays, and in the Lower Laguna Madre. Other areas of Redfish Bay were seined in 1962 without ob­taining any species but pink shrimp. While shrimp biologists often point out the importance of inshore nursery grounds to maintenance of pink shrimp stocks, we are not aware of emphasis on linking inshore nursery areas to grass communities as Hildebrand (1955) has stated. Perhaps this is taken for granted but Eldred et al. (1961) do not mention this and suggest that spawning temperature is most important. Hoese has collected pink shrimp in Zostera marina in Chesapeake Bay (see also Williams, 1955) where temperatures are lower than in Texas, a region where pink shrimp are also uncommon. A sizable fishery for pink shrimp exists in North Carolina (Williams, 1955) but they are rare in South Carolina and Georgia (Power, 1959; and several annual reports of Bears Bluff Laboratories, Wadma· law Island, S. C.), where we have found no record of large expanses of spermatophyte communities. Williams (1955) did emphasize importance of cover for penaeid shrimp in general, but did not associate P. duorarum and grass in contrast to other species. Wil­liams (1958) also found that it chose a bottom type different from two other species of Penaeus. PINFISH The pinfish, Lagodon rlwmboides, was the most abundant fish species with the largest biomass. A very large May-June peak was followed by a July-August low and a smaller August-September peak (Figs. 8, 10) . Except for the summer absence this pattern cor­responds closely with Hellier's (1962) collections. Hellier (1962) sampled a slightly older and larger population from somewhat deeper waters. Apparently post-larval pinfish entered the bay at a size of about 15 mm between Feb­ruary and May with largest numbers in April. SEASONA'L PATTERNS OF OTHER ANIMALS The summer data on snapping shrimp, Alpheus heterochaelis, were inaccurate due to their burrowing habits. None were taken in the trap during the hot summer months, but specimens were found by digging in the bottom where temperatures were up to 7° C cooler. For a short time in late winter and early spring, grass shrimp, Palaeomonetes pugio, were extremely abundant (Fig. 5). Weights and counts were below actual values since very small shrimp passed through the nets. Rapid decline of the population began in March and by May they were rare. It is possible that other species occur in Redfish Bay, but specimens in the February peak were identified as P. pugio. Blue crabs, Callinectes sapidus, reached a peak in March and April but rapidly disap­peared and remained scarce throughout the study (Fig. 6). This late winter-early spring abundance and subsequent emigration has been shown by Daugherty ( 1952) in other bays. Neopanope texana was the dominant mud crab in the bay. It was most abundant dur­ FIG. 5. Catch of grass shrimp, Palaem.onetes FIG. 6. Catch of blue crabs, Callinectes sapi­pugio. dus. ing the hottest periods in June and July (Fig. 3) in contrast with most other species. Lucania parva was widespread in the samples, but became abundant in July and Au­gust when other species were disappearing (Fig. 3). Large schools of mullet, Mugil cephalus, occurred next to spoil banks, but did not inhabit the grassy areas in numbers until late summer and fall. Juveniles were taken only once (January 22). Adults were wary and difficult to catch even if caught in the trap. Silversides, Menidia beryllina, were sporadic in occurrence until June. A sharp popu­lation increase occurred in late September and early October, after which they became scarce. A mojarra, Gerres cinereus, was apparently another species characteristic of the com­munity. Young appeared in June and reached a small population peak in August and September. Tabb and Manning (1961) reported this to be the most abundant mojarra in Florida Bay, which has grass flats. Two population peaks of spot, Leiostomus xanthurus, occurred, one in spring and a smaller one in fall, with summer and winter absences in between (Fig. 7). Very small juveniles (20-30 mm) were taken only in spring. A goby, Gobiosoma robustum, is another "indicator" species of grass flats (Springer and McErlean, 1961). It was taken in largest quantities in winter months, but since gobies are secretive, they may have been missed at other times. A few other species were taken less commonly. These include Anchoa hepsetus, Strongylura marina, Syngnathus scovelli, Hippocampus zosterae, Orthopristis chrysop­terus, Archosargus probatocephalus, Gobionellus boleosoma, Sciaenops ocellata, Bairdi­ella chrysura, and Paralichthys lethostigmus of the fishes. Several other invertebrates were inadequately sampled, even though occasionally taken in the trap. One of these was Callinectes danae, which appeared in April after Logodon rhomboides 300 Leiostomus xonthur us 60 200 40 "' tosynthesis in the Laguna Madre of Texas. Pub!. Inst. Mar. Sci. Univ. Tex. 8: 212-215. Hildebrand, H. H. 1954. A study <>f the fauna of the brown shrimp (Penaeus aztecus Ives) grounds in the western Gulf of Mexico. Puhl. Inst. Mar. Sci. Univ. Tex. 3(2): 1-366. Hildebrand, H. H. 1955. A study of the fauna of the pink shrimp (Penaeus duorarum Burkenroad) grounds in the Gulf of Campeche. Pub!. Inst. Mar. Sci. Univ. Tex. 4(1): 169-232. Ladd, H. S. 1951. Brackish-water and marine assemblages of the Texas coast with special reference to mollusks. Pub!. Inst. Mar. Sci. Univ. Tex. 2(1): 129-162. Marmer, H. A. 1954. Tides and sea level in the Gulf of Mexico, p. 108-118. In Gulf of Mexico, its origin, waters, and marine life. Fish. Bull. U.S. 89. Odum, H. T., and R. F. Wilson. 1962. Further studies on reaeration and metabolism of Texas bays. 1958-1960. Pub!. Inst. Mar. Sci. Univ. Tex. 8: 23-55. Odum, H. T. 1963. Productivity measurements in Texas turtle grass and the effects of dredging an intracoastal channel. Puhl. Inst. Mar. Sci. Univ. Tex. 9: 45-58. Power, E. A. 1959. Fishery statistics of the United States. U. S. Bur. Comm. Fish Stat. Digest (51): 1-457. Reid, G. K., Jr. 1954. An ecological study of the Gulf of Mexico fishes, in the vicinity of Cedar Key, Florida. Bull. Mar. Sci. Gulf Caribb. 4(1): 1-94. Springer, Stewart, and H. R. Bullis. 1954. Exploratory shrimp fishing in the Gulf of Mexico, sum­mary report for 1952-1954. Comm. Fish. Rev. 16(10): 1-16. Springer, V. G., and A. J. McErlean. 1961. Spawning seasons and growth of the code goby, Gobio­soma robustum (Pisces, Gobiidae) in the Tampa Bay area. Tulane Stud. Zoo!. 9(2): 87-98. Springer, V. G., and K. D. Woodburn. 1960. An ecological study of the fishes of the Tampa Bay area. Fla. St. Bd. Consv. Prof. Pap. ( 1) : 1-104. Tabb, D. C., and R. B. Manning. 1961. A checklist of the flora and fauna of Northern Florida Bay and adjacent brackish waters of the Florida mainland collected during the period July, 1957, through September, 1960. Bull. Mar. Sci. Gulf Caribb. 11 (4) : 552-649. Volkmann, C. M., and C. H. Oppenheimer. 1962. The microbial decomposition of organic carbon in surface and sediments of marine bays of the central Texas Gulf coast. Puhl. Inst. Mar. Sci. Univ. Tex. 8: 80-96. Williams, A. B. 1955. A contribution to the life history of the commercial shrimp (Penaeidae) in North Carolina. Bull. Mar. Sci. Gulf Caribb. 5 (2): 116-146. Williams, A. B. 1958. Substrates as a factor in shrimp distribution. Limnol. & Oceanogr. 3(3): 283-290. TABLE 1 Most abundant animals taken in quadrat. First figure is average per month in gms/m2; second figure (in parentheses) is the average number taken per sample. Jan . Feb. Mar. Apr. May Jun . Jul. Aug. Sep. Oct. Nov. Dec. Lucania parva 0.008 (4) 0.007 (3) 0.004 (1) 0.017 (4) 0.008 (4) 0.004 (2) 0.1 (39) 0.24 (160) 0.1 (68) 0.12 (83) 0.283 (183) 0.2 (131) Cyprinodon variegatus x (1) x (1) x (1) 0.18 (11) Menidia beryllina 0.023 (1) 0.008 (12) 0.002 (3) 0.18 (30) 0.05 (11) 0.07 (8) 0.8 (87) 0.9 (105) 0.13 (4) Gerres cinereus 0.008 (10) 0.004 (4) O.Q7 (23) O.Q75 (10) 0.02 (6) 0.02 (8) Leiostomus xanthurus 0.004 (5) 0.04 (23) 0.52 (96) 0.189 (15) 0.03 (2) 0.15 (4) 0.07 (2) 0.03 (1) Lagodon rhomboides 0.001 (1) 0.15 (66) 0.49 (95) 1.3 (295) 2.14 (252) 1.52 (94) 0.3 (23) 0.6 (32) 0.98 (47) 0.3 (17) 0.072 (5) Gobiosoma robustum 0.008 (3) 0.016 (2) 0.022 (6) 0.033 (1) 0.016 (4) 0.001 (1) 0.003 (15) x (1) 0.006 (5) 0.04 (19) Total fishl 0.02 (8) 0.32 (76) 0.58 (126) 1.89 (408) 2.36 (278) 1.58 (139) 0.45 (92) 0.98 (224) 2.10 (217) 1.40 (215) 0.59 (213) 0.40 (154) Penaeus duorarum Palaemonetes pugio Alpheus heterochaelis Neopanope texana Callinectes sapidus 0.034 (25) 0.010 (4) 0.051 (7) 0.325 (26) 0.08 1.8 0.06 0.02 1.4 (6) (828) (10) (2) (59) 0.'18 0.75 0.006 0.069 1.2 (32) (313) (2) (17) (45) 0.5 0.63 0.113 0.9 (208) (302) (25) (43) 2.1 0.031 0.01 0.036 0.228 (234) 0.96 (15) 0.001 (1) 0.009 (6) 0.085 (21) 0.002 (92) (2) (1) (16) (1) 0.35 0.08 0.4 (41) (11) (75) 0.06 0.001 0.19 (12) (1) (31) 0.17 0.004 0.005 0.13 0.007 (17) (2) (1) (13) (1) 0.55 0.02 (53) (4) 0.89 0.03 0.06 (93) (2) (21) 0.02 0.20 0.12 (4) (249) (12) Total invertebrates2 0.73 (62) 3.36 (905) 2.20 (409) 2.14 (578) 2.40 (277) 'l.06 (112) 0.83 (127) 0.45 (44) 0.32 (34) 0.57 (57) 0.99 (116) 0.34 (265) TOTAL1·2 0.74 (70) 3.68 (981) 2.78 (535) 4.02 (986) 4.76 (555) 2.37 (251) 1.29 ( 219) l.43 (268) 2.42 (251) l.97 (272) 1.58 (329) 0.74 (419) 1 Less Mugil cephalus and Opsanus beta. 2 Less Libinia dubia. 3 X indicates weight of a single individual less than 0.1 g. Productivity Measurements in Texas Turtle Grass and the Effects of Dredging an lntracoastal Channel HOWARD T. 0DUM1 Institute of Marine Science, The University of Texas Port Aransas, Texas Abstract Measurements of benthic chlorophyll "A" and diurnal oxygen productivity were made in turtle grass beds containing Thala.ssia testudinum and Diplanthera wrightii in Redfish Bay, Texas, before and after the dredging of an intracoastal canal. Moderate values of photosynthesis 2 to 8 g 0 2/m2 per day were observed in the spring of 1959 following a period of shading by turbid dredge-waters, but exceptionally high values 12 to 38 g/m2 per day were recorded the following spring in those areas not smothered with silt. Chlorophyll "A" in 1959 averaged 0.0338 g/m2 but increased to 0.68 g/m2 the following summer. Introduction The high productivity of turtle grass ecosystems in Texas, Florida, and Puerto Rico has already been established by previous measurements of diurnal properties. Oxygen production values, for example, have been found up to 40 g/m2 per day (Odum, 1957; Odum and Hoskin, 1958; Odum, Burkholder, and Rivero, 1959; Odum and Wilson, 1962). Bottle studies compared with free water measurements (Odum and Hoskin, 1958) indicated the minor role of plankton production as compared with benthic pro­duction in these flats. High densities of juvenile animal populations in these shallow sys­tems have been established in an annual study in Texas flats with the drop net by Hoese and Jones (1963), and by studies of Springer and Woodburn (1960). High values of Chlorophyll "A" in the benthic plants were given by Odum, McConnell, and Abbott (1958). These indices support the concept that is widely held in the Gulf Coastal region that the grassy shallows are food production nurseries, at least during the warmer sea­sons. Schultz (1961) discusses the distribution of juvenile fish and shrimp in the study area. In 1959 an intracoastal channel 12 ft deep and 125 ft wide was dredged through Redfish Bay, Aransas Pass, Texas, an area of fertile grass previously studied as cited above. Data on this bay· were obtained relative to the dredging operation by several persons. Kornicker, Oppenheimer, and Conover (1959) described some mud-balls re­sultings from the dredging. Hellier and Kornicker ( 1962) described the stations and the sedimentological effects in which there was heavy sediment accumulation associated with a spoil island extending about 0.2 mile. Ronald Schultz (personal communication) reported some variable animal collections from push net and shovel-sieve sampling at the same stations. Lucina pectinata and Chione cancellata were predominant. This report 1 Present address: Puerto Rico Nudear Center, Rio Piedras, P.R. Productivity Measurements in Texas Turtle Grass concerns two indices of productivity, diurnal oxygen curves and chlorophyll "A" during this period. Area and Sequence of Events Redfish Bay is pictured in the map in Fig. 1. Fig. 2 has aerial photographs of the study area facing east from the spoil bank along the transect line of 5 stations set up at about 0.25 mile intervals. Prior to dredging the water was deepest at station 1 where Thalassia beds were maximal (about 0.5 m at ordinary tide levels), shoaling gradually to 0.30 m at station 5 with increasing percentages of Diplanthera. Station distances given in Hellier and Kornicker (1962) were apparently too large. Some measurements of productivity were made in similar grass in the area of Ransom Island south of the Port Aransas Causeway in 1957. The transect of station poles was set up north of the causeway in November 1958. The dredge began to affect the area in the last of February 1959 with clouds of drifting silt obscuring the grass on many days Gu lf of 2 miles FIG. 1. :\Iap of Redfish Bay near Aransas Pass, Texas, indicating the study area, the 5 stations, the intracoastal channel, and the Ransom Island 'Station. Productivity Measurements in Texas Turtle Grass FIG. 2A. Aerial photographs: above, March 21, 1961, with a view facing east across the new spoil island along the transect of 5 stations. Note the outline of the uncovered grass between stations 2 and 3. Below, new channel and spoil islands. around March 1, 1959. Then dredging was stopped when rock was reached so that by March 13 the dredge had been removed and the water again was clear. No spoil island had been deposited at this time in the transect area. Final dredging began again in November 1959 with the deposition of the spoil island and silt on top of the grass as far as station 2 as seen in Fig. 2. Thereafter measurements of productivity were made in the vicinity of station 3, which received a few centimeters of silt only. Methods, Replications Within the Bay System Measurements of productivity with the diurnal method were made as described in detail in a previous paper (Odum and Hoskin, 1958). Fig. 3 is a representative diurnal graph with computations as used for estimating gross production and total community respiration. Following the earlier studies on this and other similar shallow bays in which the aeration coefficient on a volume basis was observed to be relatively conservative Productivity Measurements in Texas Turtle Grass FIG. 2B. Aerial view of turtle grass beds (dark areas) prior to dredging of the intracoastal chan­nel. Photograph was taken March 20, 1950 by the U.S. Production and Marketing Administration (DIX-6G-49). (Odum and Wilson, 1962), a constant reaeration constant (k) was used in this paper as 1g02/m3 per hr for 100% deficit gradient across the water-air interface. In the preceding paper some duplicate stations were studied in Redfish Bay along with some measurements within a fiber glass enclosure, Similarly, in the data taken in 1961, 2 to 5 duplicate stations were measured in order to indicate homogeneity and heterogeneity of the circulating waters. Some representative curves reproduced in Fig. 4 indicated a general similarity in metabolic patterns at the main stations in the waters over the grass flats of Redfish Bay. Each curve was based on sample pairs taken at each time of measurement. The moving water averaged the production over sizeable areas. Thus, samples taken at different stations as shown in Fig. 4 were sub-samples. When the productivity for each curve was computed separately, station differences were greater (Fig. 5) because the station depths were different. The general similarity of the graphs in Fig. 4 may justify computations which were made when data from only one of these stations was obtained. The approximation of constant daytime and nighttime respiration often used in pro­ductivity studies for lack of better information was continued in this paper throughout for purposes of uniformity although it was recognized that this approximation may be far from accurate. In considering the ratio of P (gross photosynthesis) to R (total system Productivity Measurements in Texas Turtle Grass respiration) any error m drawing the base line for daytime respiration affects both P and R. In Fig. 6 is reported one graph in which the diurnal oxygen and diurnal carbon metabolic rates are both plotted. The carbon-dioxide metabolism was computed with the pH-C02 titration method (Beyers and Odum, 1959). pH was taken with a Beckman PEDFISl-4 BAY RANSOM ISLAND BRIDGE (DEPTH 75CM) JUNE 21,1960 ONE VEAR AFTER DREDGI NG 9.0~--------------, 0 0 '0 >.0"---~---~---~------0 l 0 O.< "' " "' 5 z "' 0.0 ~ -o• ... "' ;i 0600 100 % i{ZJ 80 LIGHT TRANSMISSION FIG. 3. Diurnal curve from a station near Ran­som Island, June 21, 1960, the summer following the dredging. Vertical transmission of white light with a selenium photometer and frosted glass is provided in the lower graph. Summer graphs like this one show a post-sunset bulge and artifact due to the strong evening sea breeze providing in­creased aeration not allowed for in the difftission correction. -....1"--:-:-:i .,. !'Id :ncrease; 02 18 mg /l 12 '8 HOURS FIG. 4. Oxygen curves taken at more than one station at the same time. Metabolic figures based on these curves were computed separately and included as points in Fig. 6. Productivity Measurements in Texas Turtle Grass Model W industrial meter operating in the field from a generator. The quotient of carbon to oxygen metabolism was 1.3 for gross photosynthesis and 1.25 for respiration. Since the carbon-metabolism data do not involve a diffusion correction and since the quotients are not greatly off from the range expected in ordinary metabolism of single organisms in aerobic processes, some additional confidence may be derived concerning the interpre­tation of the figures for P and R. The kind of abnormal respiratory quotients found in some polluted systems, anaerobic marine bays, and bottle studies, were apparently not involved in the aerobic grass flats. Three other examples were studied in grass flats of the Lower Laguna Madre (Table 2). Chlorophyll "A" was measured in the benthic plants as described in Odum, McCon­nell, and Abbott (1958). Conover's stove pipe sampling procedure was used to collect the plants which were washed, ground, aliquoted, and extracted in acetone. Whereas the freewater diurnal values represented larger expanses of the bay averaged, chlorophyll measurements of benthic plants served as an index of localized fertility. Results Fig. 3 is a typical diurnal record of oxygen with graphic computations for estimating gross photosynthesis and total community respiration. Fig. 6 is a record of the diurnal curve measurements in Redfish Bay grass flats from 1957 through 1961, each pair of points representing one diurnal record like that in Fig. 3. A record of salinities, the times of dredging, and other events, are also noted. The strongly seasonal pulse of productivity like that previously found in the Laguna Madre in a 4 year series is recognizable with winter minimum. Chlorophyll "A" contents of the benthic plants in 1959 and 1960 are reported in Table 1 with very large differences observed. The relatively sparse grass during 1959 was followed by thick growths in 1960 as indicated in the chlorophyll "A" figures. The dry weights of benthic plants per m2 for July 26 samples (stations 3, 4, and 5) were 470, 322, 464, 427; 634, 409, 418, 516; 232, 192, 181, 217. The weights per area were less than turtle grass weights in Puerto Rico measured by Burkholder (1959) reflecting in part the smaller proportionate weight of the rhizome systems in the Texas beds. The Redfish Bay beds during the sparse condition of summer 1959 were apparently similar in density to those of Boca Ciega Bay, as reported by Pomeroy (1960) with 0.054 g/m2 of benthic chlorophyll and 81 g/m2 dry plant matter. The productivity and chlorophyll "A" data indicate diminished fertility during the year 1959 when there was some disturbance and shading in the spring. Values of photo­synthesis and chlorophyll were less than in previous years. In contrast, 1960, the year immediately after dredging, had unusually heavy growths and higher values of photo­synthesis and chlorophyll than observed previously, except in stations 1 and 2 where the benthic communities had been smothered with soft silt. On February 7, 1961, after the annual winter decline, chlorophyll "A" values were as high as those in the summer of the dredging. Winter values in winter of 1958 before dredging ranged 0.04-0.48 g/ m2 • Station 2 was examined further during the fall of 1962 and still had no growths other than microscopic algae and a few diminutive blades of Ruppia. There was an algal crust but the silt below was little consolidated. In previous studies an excess of respiration over photosynthesis was noted when salinity was falling in Texas bays associated with river-borne organic matter, but photo­ Productivity Measurements in Texas Turtle Grass pH and C02 water Titrations 9 .0 pH 8.5 0.1 0.2 0.3 0.4 0.5 0.6 C02 change millimoles/I 9.0 pH 8 .5 HOURS 0 .1-----------------------­ · I I I I I I ::::> ._ I I 0 .c. I ...... : I ...... (/) Q) o E ,,'' / E ,'----­ , l._ ________ 0.1"------L-----L----...1...-----J 06 12 18 24 HOURS Frc. 5. Diurnal oxygen and pH curves for Redfish Bay, station 2, Aug. 15-16, 1961. The rate of change graphs for both oxygen and carbon are plotted together below on a millimole per hour basis. The carbon curve is reversed with increasing values plotted downward. 14 24 Productivity Measurements in Texas Turtle Grass REDFISH BAY JFMAMJ JASOND JFMAMJ JASOND JFMAMJ J ASOND 1959 1960 1961 Frc. 6. Record of salinity, gross photosynthesis, and total respiration 1957-1961. Data represented by crosses (x) were taken near Ransom Island (Fig. 1) whereas the other data were taken between stations 2 and 3 in the transect. synthesis and respiration in high salinity waters of Redfish Bay were usually similar. The 1959 data were distinctive with a greater imbalance with excess respiration over photosynthesis. Much higher R than P was found in the fall of 1960 at a time when excessive benthic growths of the previous year were decaying and salinities were diminishing. Diurnal productivity data from the grass beds near Port Isabel, Texas are included in Table 2. The values were comoarable with those in the Redfish Bay area. Productivity Measurements in Texas Turtle Grass TABLE 1 Chlorophyll "A" in benthic plants along the Redfish Bay transect in 1959 and 1960. Data in g/m2 Winter JI Distance £rom Summer Summer 1961Stal ion new channel 1959 1960 0 0.0078* Station now 0.0113* out of water 0.0180* as spoil island. 0.0086* 0.029* 0.052* 0.0015* 0.1'15* 0.04lt 2 0.25 mile east 0.0208:1: Beds 0.0106:1: covered 0.0074:1: with 30 0.0052:1: cm of 0.0105:1: soft silt; O.OllOt no plants. 3 0.5 mile east 0.079§ 0.042§ l.14U l.21U 0.021 0.019 0.087§ l.32ff 0.153 0.022§ l.46U 0.103 0.062t 0.'130 0.012 0.055 0.133 0.75 mile east 0.087§ 0.26U 0.033§ 0.42ff 0.011§ 0.49U 0.048t 0.47ff 5 1.0 mile east 0.050§ 0.20ff 0.022§ 0.26U 0.0195t 0.28U Mean 0.03379 0.6827 • Ma~· 30~ 1959. t Jul,· 15, 1959. ! April 27, 1959. § June 30, 1959 . fi July 26, 1960. II Feb. ~, 1961. TABLE 2 .\Ietabolism of Turtle Grass Bay Areas in the Lower Laguna Madre at Port Isabel, Texas Depth Salinity %0 T Oxygen g/m2/day p R Carbon g/m2/ day p R Quotient co,10. AQ RQ August 8-9, 1960 1.4 1.4 0.9 37 37 37 28-30 28-30 28-30 26.3 30.0 11.7 13.8 19.7 4.3 J anuary 20-22, 1961 1.8 30 11-12 4.0 5.8 July 3-4, 1961 Port Isabel Laguna Vista Queen Isabel Causeway 1.5 1.0 1.0 37 40 36 10.8 11.2 7.4 8.3 10.3 9.6 3.6 11.2 6.7 3.0 6.8 7.4 0.9 1.7 2.4 1.0 1.8 1.5 Discussion Data reported here indicate a marked seasonal cycle in productivity with considerable year to year variation possible. The values for the Redfish Bay Turtle Grass were not as high as some grass flat data in the lower Laguna Madre of Texas where higher values were recorded associated with clearer waters (Odum and Wilson, 1962). The decreased productivity and imbalance of respiration over photosynthesis of the summer of 1959 may have been associated with the silts turned loose over the flats by the start of dredging that spring. Certainly, during the weeks of dredging nearby, light penetration was much reduced and the plant beds may have received a set-back at this time. Whatever diminished productivity during that year was not permanent. Growths the following year were exceptional. The suggestion by Ingle ( 1952) that dredging may stimulate by adding nutrients may have merit. Apparently, therefore, the channel dredging entirely removed from the available nursery grounds the 125 ft of channel and a quarter of a mile of beds under and adja­cent to the spoil island, but did not permanently damage the productivity of the beds beyond. A geometric consideration may be important in comparing these results to those given by Ingle (1952) and Mackin (1962) for dredging in slightly deeper waters. Where the spoil from a channel of this dimension is discharged in only 0.5 m of water or less, it may shoal the water depth critically over a much wider zone than where the discharge is into a bay that is already 3 to 10 ft in depth. In the fall and winter of 1960--1961, respiration remained higher than photosyn­thesis. Close similarity of P and R which was observed in Redfish Bay in 1957 and 1960 and in 4 years in the Laguna Madre was upset. The great mats of decaying grass ob­served in the fall of 1960 due to the exceptional growth that summer and the influx of low salinity river water may have raised respiration rates. P and R were again in balance during the growing season of 1961, but another excessive respiration period was found following Hurricane Carla, possibly reflecting the upset bottom conditions following an approximate 8 ft tide and storm waves over the flats. Photosynthesis Oct. 31, 6 weeks following the hurricane, was less than photosynthesis at this time in other years. Because the center of the storm went inland to the east, rains in the Redfish Bay area were not excessive and salinities in this bay did not fall excessively. Thomas, Moore, and Work ( 1960) found extensive windrows of turtle grass following a hurricane in the Miami area, but showed from weight calculations that the portions of the beds washed ashore were negligible. The record of metabolism and chlorophyll "A" as reported over the period from 1957 through 1961 indicated some pattern of a regular seasonal pube, but the changing patterns of precipitation, hurricanes, and man-made interferences such as dredging were apparently keeping the ecosystem metabolically upset so that the kind of steady state found in shallow aquarium ecosystem of benthic plant type (Beyers, 1963) did not become established. The imbalances of P and R were related to the type of disturbance such as organic storages and lags; bottom disturbances; organic river imports; and damage to plant beds. Productivity Measurements in Texas Turtle Crass Acknowledgments These studies were aided by an interagency contract between the Institute of Marine Science and the Texas Game and Fish Commission No. 4413-347, and the U. S. Public Health Service through Grant WP 00204-02. Aid of associates and assistants in diurnal series and sampling is gratefully acknowledged including: Robert J. Beyers, T. Hellier, Norman Vick, Mrs. Barbara Beyers, Mrs. Mary Ann C. Davis, John Conover, Frank Schlicht, Charles Wise, and G. Garza. Photographs taken by the Texas Game and Fish Commission were supplied by Ronald Schultz. Literature Cited Beyers, R. J. 1963. The metabolism of twelve aquatic laboratory microecosystems. Ecol. Monogr. 33(4): 281-306. Beyers, R. J., and H. T. Odum. 1959. The use of carbon dioxide to construct pH curves for the measurement of productivity. Limnol. & Oceanogr. 4: 499-502. Burkholder, P. 1959. Some chemical constituents of turtle grass Thalassia testudinum. Bull. Torrey bot. Cl. 86: 88-93. Hellier, T. R., and L. S. Kornicker. 1962. Effect of hydraulic dredging on sedimentation. Puhl. Inst. Mar. Sci. Univ. Tex. 8: 212-215. Hoese, H. D., and R. S. Jones. 1963. Seasonality of larger animals in a Texas turtle grass com· munity. Pub!. Inst. Mar. Sci. Univ. Tex. 9: 37-47. Ingle, R. M. 1952. Studies on the effect of dredging operations upon fish and shellfish. Tech. Ser. Fla. Bd. Conserv. 5: 1-26. Kornicker, L. S., C. H. Oppenheimer, and J. T. Conover. 1959. Artificially formed mud balls. Puhl. Inst. Mar. Sci. Univ. Tex. 5(1958): 148-150. Mackin, J. G. 1962. Canal dredging and silting in Louisiana Bays. Pub!. Inst. Mar. Sci. Univ. Tex. 7 : 260--314. Odum, H. T. 1957. Primary production measurements in eleven Florida springs and a marine turtle grass community. Limnol. & Oceanogr. 2 : 85--97. Odum, H. T., and C. M. Hoskin. 1958. Comparative studies of the metabolism of marine waters. Pub!. Inst. Mar. Sci. Univ. Tex. 5: 16-46. Odum, H . T., W. McConnell, and W. Abbott. 1958. The Chlorophyll "A" of communities. Pub!. Inst. Mar. Sci. Univ. Tex. 5: 65--96. Odum, H. T., P. R. Burkholder, and J. Rivero. 1959. Measurements of productivity of turtle grass flats, reefs, and the bahia fosforescente of southern Puerto Rico. Pub!. Inst. Mar. Sci. Univ. Tex. 6: 159-170. Odum, H. T., and R. F. Wilson. 1962. Further studies on reaeration and metabolism of Texas Bays, 1958-1960. Pub!. Inst. Mar. Sci. Univ. Tex. 8: 23-55. Pomeroy, L. R. 1960. Primary productivity of Boca Ciega Bay, Florida. Bull. Mar. Sci. Gulf Caribb. 10: 1-10. Schultz, R. L. 1961. Fisheries investigation in the Aransas-Copano Bay System-Job Report C-1, Project M-6R-3. Texas Game &Fish Commission, p. 1-4. Springer, V. G., and K. D. Woodburn. 1960. An ecological study of the fishes of the Tampa Bay area. Prof. Pap. Ser. Fla. Bd. Conserv. Mar. Lab. 1: 1-104. Thomas, L. P., D. R. Moore, and R. C. Work. 1960. Effects of Hurricane Donna on the turtle grass beds of Biscayne Bay, Florida. Bull. Mar. Sci. Gulf Caribb. 10: 191-197. Amino Acids in Redfish Bay, Texas1 KILHO PARK,2 W. T. WILLIAMS,a J.M. PRESCOTT3 AND D. W. HoOD4 Abstract Approximately 18 different amino acids in acid-hydrolyzates of dissolved organic matter in the sea water of Redfish Bay, Texas, have been identified by ion exchange chromatography. The organic mat­ter was initially isolated from sea water by ferric hydroxide co-precipitation method. The amino acids identified are: glutamic acid, aspartic acid, glycine, serine, alan:ne, lysine, leucine, threonine, iso­leucine, arginine, tyrosine and phenylalanine, proline, valine plus cystine, omithine, fi-alanine, histi­dine, methionine and methionine-sulfoxide. Although not strictly quantitative, the results indicate that higher concentrations of amino acids are dissolved in a fertile bay water than in open sea water. Introduction Because organic matter dissolved in sea water often occurs in concentrations of 1 mg/liter while there coexist about 35 g/liter of inorganic salts, it is not easy to isolate and concentrate sufficient quantities of the organic matter without destroying or altering it. Despite the experimental difficulties, progress has been made in the field of organic chemistry· of the sea in recent years. Vallentyne (1957) and Duursma (1960) compiled lists of various dissolved organic substances found in sea water. Jeffrey and Hood (1958) evaluated various methods for the isolation of organic matter in sea water. They found that co-precipitation of the organic matter with ferric hydroxide was an effective way to concentrate a part of the · dissolved organic matter. Recent experiments on the recovery of known amounts of CH-labeled amino acids in sea water by the ferric hydroxide co-precipitation method yielded a recovery range of a minimum of 30% for alanine and a maximum of 85% for lysine. A study of the recovery of peptides and proteins is under way at the Chemical Oceanography Laboratory of A. and M. College of Texas. Preliminary results indicate nearly quantitative yields. By the use of the ferric hydroxide co-precipitation method, Tatsumoto et al. ( 1961) and Park et aL (1962) investigated the occurrence of amino acids in acid-hydrolyzates of the dissolved organic matter from open sea waters. They identified about 18 different amino acids by ion exchange chromatography developed by Moore, Spackman and Stein (1958). Higher concentrations of dissolved organic matter have been reported in fertile bays than in the more open water by Collier (1958), Collier et al. ( 1953) , Wangersky (1952), Wilson (1961) and others. A question can be raised whether the amino acids are more concentrated in such productive waters than open waters. Using the experimental pro­ 1 Based on part of a dissertation submitted by the first author in partial fulfillment of the require­ ments for the degree of Doctor of Philosophy at the Agricultural and Mechanical College of Texas, College Station, Texas. 2 Department of Oceanography, Oregon State University, CorvalFs, Oregon. 3 Department of Biochemistry and Nutrition, Agricultural and Mechanical College of Texas, College Stat'on, Texas. 4 Department of Oceanography and Meteorology, Agricultural and Mechanical College of Texas, College Station. Texas. Amino Acids in Redfish Bay, Texas cedure followed previously (Park et al., 1962), a study was made of the occurrence of amino acids dissolved in the water of Redfish Bay near Port Aransas, Texas. This is a fertile inshore bay, dominated by turtle grass beds. Methods WATER SAMPLING On 16 May 1960 approximately 170 liters of sea water were collected from Redfish Bay, at the same location occupied for studies of diurnal pH variation by Park, Hood and Odum (1958). Several milliliters of chloroform were immediately added to the water to reduce the metabolic activities of living organisms. At the station, the water was filtered through Curtin No. 7775 general laboratory type filter paper. The water was then immediately brought back to the laboratory in polyethylene containers, and was filtered once more through HA Millipore® filters. Co-PRECIPITATION OF ORGANIC MATTER WITH FERRIC HYDROXIDE The filtered sea water was placed in a polyvinyl chloride plastic tank. Under vigorous stirring, 50 ml of 2 M FeCl3 solution were added to the sea water. After several minutes, 2 N NaOH solution was added to raise the pH of the sea water to 9.0-9.1. After the stirring was continued for 30 minutes, the precipitates were allowed to settle overnight. The precipitates were then drawn into a small container. Further removal of remaining sea water was achieved by centrifugation. The precipitates were then dissolved with a minimum amount of 1 N HCI solution. SEPARATION OF PROTEINACEOUS FRACTION FROM THE Co-PRECIPITATED ORGANIC MATTER The pH of the dissolved ferric hydroxide precipitates was adjusted to 1.0 by adding a slight amount of either HCl or NH40H. The resulting solution was then passed through Dowex-50 cation exchange resin column, H+ form, X 8, 200-400 mesh, 9 X 60 cm, at a flow rate of 1-2 ml/min, followed by 3 liters of 0.1 N HCI. After the resin column had been washed with 3 liters of triple distilled water, the pro­teinaceous fraction of the organic matter was eluted with 8 liters of 2 N NH,OH at a flow rate of 1-2 ml/min. The volume of the fraction was condensed to 500 ml at 60° C under low pressure. The pH of the proteinaceous fraction was raised to 9.5 by adding NaOH. The solution was then passed through IRA-400 anion exchange resin column, OH-form, 200-400 mesh, 7 X 60 cm, at a flow rate of 1 ml/min. The proteinaceous fraction retained on the resin column was eluted with 3 liters of 2 N HCl at a flow rate of 3 ml/min. The efiluent thus obtained was then condensed to 200 ml at 60° C under vacuum. The condensed solution was refluxed for 24 hours in 6 N HCl solution under atmospheric pressure. The acid-hydrolyzed proteinaceous fraction was dried by a combination of low temperature evaporation and freeze-drying. AMINO Acrn RESOLUTION BY loN ExcHANGE CHROMATOGRAPHY An approximately 100-liter sea water equivalent of the amino acid sample was dis­solved in 5 ml of 0.1 N HCI. An aliquot of 2 ml, equivalent to 40 liters of original sea Amino Acids in Red fish Bay, Texas water, \ms loaded on a Amberite CG-120 cation exchange resin column which had been graded to size by hydraulic flow by the Hamilton's method (1958). The Na+ form of the resin, prepared by washing with 2 N NaOH, was equilibrated with a 0.2 M sodium ci­trate buffer solution at a pH value of 3.25. A 150-cm column effective in the separation of neutral and acidic amino acids was used for chromatographic resolution. The sample in the column was eluted with a 0.2 M sodium citrate buffer solution at a pH of 3.25 at 30° C until alanine emerged from the column. The volume of effiuent re­quired to reach this stage was approximately 300 ml. At this point, the pH of the column was changed to 4.25 by adding a 0.02 M sodium citrate buffer solution at 50° C. All the amino acids except the basic forms were eluted in an effiuent of 640 ml. In order to separate the basic amino acids, a second column, 50 cm, but of larger parti­cle size and equilibrated with 0.38 M, pH 4.26, sodium citrate buffer solution, was used. After the emergence of 400 ml of effiuent, the pH of the buffer solution was changed to 6.5 by adding 0.38 M sodium citrate. The elution was continued until 640 ml. Two-ml fractions of all effiuents were collected in test tubes, and a ninhydrin test was performed on all the fractions. The results of the ninhydrin test were expressed as leu­cine equivalent in micromoles. Results and Discussion Figures 1 and 2 show the ion exchange chromatograms of amino acids obtained from 15 liters of Redfish Bay water. Approximately 18 different amino acids were identified by comparing these with the chromatograms of known amino acids. The quantities of amino acids, without any correction for losses occurring during the assaying, are listed in Table I. The reproducibility of the chromatographic separation gave an average precision of 5%. TABLE 1 Amino acids found in the sea water of Redfish Bay, Texas by ferric hydroxide co-precipitation method Amino acids mg/ m3 ,umole/ m3 Glutamic acid 5.5 38 Aspartic acid 5.4 41 Glycine 4.9 65 Serine 3.0 29 Alanine 2.2 25 Lysine 2.1 '15 Leucine 1.9 15 Threonine 1.7 15 Isoleucine 1.3 10 Arginine 1.3 7 *Tyrosine and phenylalanine (1.3) (7) Proline 1.0 9 *Valine plus cystine (1.0) (9) Omithine 0.9 7 Cysteic acid 0.8 5 /3-alanine 0.6 7 Histidine 0.4 3 Methionine 0.3 2 Methionine-sulfoxide 0.2 1 Other ninhydrin-positive compounds (3.0) (20) Total (39) ('330) * Tht" peak~ corresponding to these amino acids were poorly resolved on the ion exchange chromatogram. Numerical values in parenlhe~t> s Wt"re e~limated. Amino Acids in Redfish Bay, Texas VJ w _J ASPARTIC 0 ACID ~2 GLYCINE ~0.200 THREONINE / u SERINE 2 1­ / z GLUTAMIC w ACID _J g \ ::i ALANINE / ISOLEUCINE 8 0 100 w z Fie. 1. Ion exchange chromatogram of acidic and neutral ami no acids. Sample: 15 liters of sea water from Redfish Bay, Texas. VJ 0.250 w _J 0 2 ~ 0200 u 2 I­ ~ 0150 _J ::i 8 0100 w z ~ 0.050 w _J 0 EFFLUENT 0 ACIDIC 8 NEUTRAL AMINO ACIDS I ~ I I AMMONIA 1----­ TYROSINE 8 1 I PH ENYLALANI NE A chromatographic peak which possibly represented ,8-alanine was observed from the bay sample, but not from open waters (Park et al., 1962). It may be a degradation product of pantothenic acid. Since our data are not corrected for the losses of organic matter which may have oc­curred during the isolation and assaying, reliable quantitative values have not been oh· tained. Further work is necessary on the development of quantitative techniques. How­ever, we find about 0.3 µ.M of amino acids in the bay water, which are several times greater than the off-shore water (Park et al., 1962). Our findings, therefore, correlate favorably with the high primary productivity of the bay (Odum and Hoskin, 1958; Park, Hood and Odum, 1958), and the high organic carbon content, 6 mg/ liter, of the bay water (Wilson, 1961). This paper merely indicates the existence of some of the common amino acids in the fertile Redfish Bay water. We hope it will help to reemphasize the importance of dis­solved organic molecules on the ecology and biochemistry of aquatic environments, which has been stressed by Collier (1953, 1958), Vallentyne (1957) and others. Acknowledgments The authors gratefully acknowledge the assistances of Dr. Yasushi Kitano and Mrs. Edith R. Isbell in field and laboratory works. This work was supported by grants A-003 and A-022 from the Robert A. Welch Foundation, Houston, Texas. Literature Cited Collier, Albert. 1953. The significance of organic compounds in sea water. Trans. N. Am. Wild]. Conf., March 1953. 18: 463-472. Collier, Albert. 1958. Some biochemical aspects of red tides and related oceanographic problems. Limnol. Oceanogr. 3: 33--39. Collier, Albert, S. M. Ray, A. W. Magnitzky, and J. 0. Bell. 1953. Effect of dissolved organic sub­stances on oysters. Fish. Bull. U.S. 84: 167-185. Duursma, E. K. 1960. Dissolved organic carbon, nitrogen, and phosphorus in the sea. Netherlands J. Sea Res. 1: 1-148. Hamilton, P. B. 1958. Ion exchange chromatography of amino acids. Effect of resin particle size on column performance. Anal. Chem. 30: 914-919. Jeffrey, L. M., and D. W. Hood. 1958. Organic matter in sea water; an evaluation of various methods for isolation. J. Mar. Res. 17: 247-271. Moore, S., D. H. Spackman, and W. H. Stein, 1958. Chromatography of amino acids on sufonated polystyrene resins. An improved system. Anal. Chem. 30: 1185-1190. Odum, H. T., and C. M. Hoskin. 1958. Comparative studies of the metabolism in Texas bays. Puhl. Inst. Mar. Sci. Univ. Tex. 5: 16-46. Park, Kilho, D. W. Hood, and H. T. Odum. 1958. Diurnal pH variation in Texas bays, and its ap­plication to primary production estimation. Puhl. Inst. Mar. Sci. Univ. Tex. 5: 47-64. Park, Kilho, W. T. Williams, J. M. Prescott, and D. W. Hood. 1962. Amino acids in deep-sea water. Science 138: 531-532. Tatsumoto, Mitsunobu, W. T. Williams, J. M. Prescott, and D. W. Hood. 1961. Amino acids in samples of surface sea water. J. Mar. Res. 19: 89-95. Vallentyne, J. R. 1957. The molecular nature of organic matter in lakes and oceans, with lesser reference to sewage and terrestrial soils. J. Fish. Res. Bd. Canada 14: 33-82. Wangersky, P. J. 1952. Isolation of ascorbic acid and rhamnosides from sea water. Science ll5: 685. Wilson, R. F. 1961. Measurement of organic carbon in sea water. Limnol. Oceanogr. 6: 259-261. Organic Carbon Levels in Some Aquatic Ecosystems1 RONALD F. wILSON2 Institute of Marine Science, The University of Texas Port Aransas, Texas Abstract An infrared gasometric method was used to investigate the organic carbon levels in the coastal waters of Texas, in contributing rivers, and in some other selected systems. The highest concentration of organic carbon found was over 100 mg/liter from samples taken from a salt pool in Puerto Rico. The lowest concentration was zero mg carbon/ liter in two springs located in Texas limestone forma· tions. Rivers fed by the springs increased in organic carbon concentration as they flowed toward the coast to 20 mg carbon/liter. In the Texas marine bays concentrations of organic carbon were 5 to 10 times higher than concentrations in the Gulf of Mexico (about 2 mg carbon/liter). Introduction Because of the difficulties with analytical methods for small concentrations of organic matter in waters where salt concentrations are high, reliable data on the levels of organic matter in marine waters are scarce and information for computing organic budgets in aquatic ecosystems have not been available. With large volumes of water involved, large amounts are involved and accurate determinations of the dilute concentrations are es­sential. In this contribution data on concentrations are reported for aquatic ecosystems of the Texas coast and elsewhere. Experimental studies on rates of change of organic matter in bottles, reefs, and cultures as verified by this direct method are reported else­where (Wilson, 1963). Methods INFRARED METHOD FOR DETERMINING ORGANIC CARBON CONTENT OF SEA WATER The infrared (1-R) method used to determine the organic carbon content of sea water samples was previously described (Wilson, 1961). Since that time, the apparatus and procedure have been improved but the principle of operation is unchanged. The 1-R method consists of: ( 1) removing all inorganic carbonates from a sample of water; (2) oxidizing the organic carbon in the sample to carbon dioxide; and (3 I meas­uring the carbon dioxide with an infrared analyzer. Inorganic carbon dioxide was removed by acidifying the sample and passing carbon dioxide-free air over it while the sample was rapidly stirred. Oxidation was accomplished by heating the sample in a closed container with potassium persulfate. The carbon dioxide resulting from the oxidation of organic matter was measured with an infrared analyzer. A diagram showing the various components of the apparatus used is presented in Fig. 1. 1 Part of a dissertation presented to the Faculty of the Graduate School of The University of Texas as part of requirements for the Ph.D. Degree in Zoology and Marine Science; aided by the U.S. Public Health Service through a research grant WP 002 04 Metabolism of Marine Bays of Texas; H. T. Odum, supervising professor. 2 Present address: Biology Department, Adelphi College, Garden City, Long Island, N.Y. Components of the System. Infrared carbon dioxide analyzer (Fig. 1): The instru­ment used which had sufficient sensitivity for measuring organic matter was a Beckman Liston Becker Infrared C02 Analyzer (model 15 A) with a 10 in. sample cell. Pump (Fig. 1): A stainless steel Dyna-Vac pump (Cole-Parmer) with an output of 430 cubic inches per min was used to circulate and mix the gas inside the closed system. A valve on the pump permitted direct regulation of the gas flow without damaging the pump. The pump maintained a sufficiently high rate of flow to flush the system of carbon dioxide but not high enough to cool the thermostated carbon dioxide analyzer. Corrosion of the stainless steel was reduced by installing the pump near the input­side of the combustion unit. Even with this precaution, corrosion remained a problem, and the inside of the pump was lightly coated with a low-vapor-pressure, carbon-free, grease to further avoid corrosion. Tube containing potassium hydroxide (Fig. 1) : The tube held approximately 200 gm of potassium hydroxide or sodium hydroxide, and constant refilling was unnecessary. A plug of glass wool was placed in the outlet of the tube to prevent potassium hydroxide dust from passing into the rest of the system where it could adsorb the carbon dioxide produced by oxidation of the organic matter. Oxidation unit (Fig. 1) : The glass combustion flask was made from a 500 ml heavy­walled Erlenmeyer fla~k which a glass blower had modified by the addition of two heavy-walled tubes. Vacuum connectors (Central Scientific Company) were used to provide seals between the glass and the metal valves. Another set of vacuum connectors sealed the entire com­bustion unit to the rest of the system. To eliminate damage to the valves from soldering or brazing them, the valves and connectors were screwed together. A piece of brass tubing, fastened to one end of the valve, joined the combustion unit to the rest of the system. Water bath (Fig. 1): A temperature-regulated water bath was used to maintain the temperature of the water sample in the combustion unit at 20 ± 1° C while the carbon dioxide was measured. The water bath was comprised of a glass tank with a cooling coil, a heater, and a thermostat. The tank was mounted on a wooden platform with a standard magnetic stirring device attached beneath it. To facilitate connecting and disconnecting the com­bustion unit, and to permit exact height adjustment of the water bath, the platform was mounted on a scissors jack. Manometer (Fig. 1): A simple mercury manometer, with a valve between it and the system, was used for testing the pressure of the system after the analysis had been com­pleted. The manom2ter consisted of a U-shaped glass tube open at both ends and half­filled with mercury. A short, heavy-walled plastic tube connected the manometer with the valve. Problems Involved in Using the 1-R Method. Two problems were encountered in using the equipment for the I-R method: gas leakage and corrosion. Leaks were eliminated by using fittings (Swagelok Company) for metal-to-metal connections; by using powdered teflon dispersed in water as a lubricant and sealer for all threads; by using metal-to­gla's and glass-to-glass fitting (Cenco Company) ; and by using bellows valves on the combustion units. Corrosion was not entirely eliminated as chlorine produced from the chloride in sea Organic Carbon Levels in Some Aquatic Ecosystems o-ring Dconnector 0 bellows ¢stopcock Manifold Organic Carbon Levels in Some Aquatic Ecosystems water during the oxidation of the samples eventually corroded the best stainless steel and monel metal. The resulting rust clogged the valves and necessitated frequent cleaning of the 1-R analyzer. If the rust was not eliminated, condensed water in the system mixed with it, producing a thick, dark brown, acidic fluid which invalidated the results of the analysis if it entered the sample cell. Attempts failed to develop glass or plastic apparatus which would not corrode since feasible glass valves were not available and the plastics tried were permeable to carbon dioxide. To minimize the problem, brass tubing and valves were used where necessary, also glass tubing and stopcocks where possible. Although brass corrodes, the corrosion by­products seemed to form a protective coat over the brass, reducing further corrosion. Measures Taken to Prowng the Use of the Components. (1). The system was thoroughly flushed with dry air to reduce corrosion when the apparatus was not in use. (2). The glass combustion flasks were annealed every 6 months to a year (depending on use) to reduce the strain on the glass from repeated heating and cooling. (3) . Since the 1-R analyzer is sensitive to vibration, it was insulated as much as pos­sible against vibrations. (4). The sample tube gradually became contaminated by dirt and film causing a zero drift. The drift was corrected with the zero adjustment on the analyzer; and the tube was occasionally cleaned and once replated with gold. To reduce the necessity of frequent cleaning and replating, a bypass tube around the analyzer was used to prevent gas flow into the sample tube except just before the carbon dioxide was to be measured. Apparatus Used for Serial Samples. The apparatus shown in the lower half of Fig. 1 was used for simultaneously removing inorganic carbon dioxide from several combustion units when serial samples were being analyzed. With this apparatus, the infrared ana­lyzer could be used exclusively for measuring the carbon dioxide samples, while the inorganic carbon removal equipment provided a steady supply of samples to be analyzed. Using nine combustion units, one worker could analyze 20 samples in a normal working day. Standardizing the 1-R Analyzer. The analyzer was standardized by injecting known amounts of pure carbon dioxide into the system after all carbon dioxide had been re­moved. For precise injections, a gas-tight syringe (Hamilton Company) was used. The carbon dioxide was injected into the system through a rubber septum similar to those used in gas chromatography. A 0.1 to 10 ml injection of carbon dioxide was made through the septum at known temperature and atmospheric pressure. The volume of carbon dioxide was adjusted to standard conditions, and the weight of carbon injected was plotted against the meter reading of the l-R analyzer. A graph was drawn for each system volume and for several gain-control settings. FrG. 1. A schematic diagram of the apparatus used for measuring the CO, resulting from the oxi­dation of organic matter. Above: an oxidation unit containing the oxidized sample is shown in a temperature-regulated water bath. The oxidation unit includes the 1-R analyzer; a filter for removing particles from the gas stream entering the analyzer; a circulating pump; a tube filled with KOH for removing CO, from the system; a manometer for measuring the pressure in the system; and a volume expansion tank. Below: the combustion unit connected to the apparatus for removing inorganic CO, from the acidi­fied sample. The combustion unit includes the oxidation flask and bellows valves connected to the flask by metal-to-glass "0" ring connectors. The unit was placed over a magnetic stirrer which vigorously stirred the water sample while CO.-free air passed over it. Organic Carbon Levels in Some Aquatic Ecosystems The standardization curve for a given volume and gain-control setting did not change as long as the analyzer was zeroed. The standardization was carried out with a volume of water in the system equal to the sample volume. The water was adjusted to pH 4 and all carbon dioxide removed from the system before the carbon dioxide was injected. The carbon dioxide was injected into the system and equilibrium between the carbon dioxide in the gas and liquid phases was reached in 15 minutes. The amount of carbon dioxide in the water during standardization was the same as in a sample of equal volume when the both had the same temperature, pH, and carbon dioxide partial pressure. In cases where the difference between the amount of carbon dioxide dissolved in l ml of sample and l ml of air was sufficiently small, the use of water in the sample cell during standardization was unnecessary, thus saving considerable time. The gain-control reduced or increased the meter deflection for a given amount of carbon dioxide; the higher the gain, the more the deflection. For high carbon dioxide concentrations, the large system volume was used in conjunction with a low gain-control setting. Procedure for Removing lnorganU: Carbon Dioxide from Sea Water Samples. Using the 1-R method, the removal of inorganic carbon dioxide from sea water samples was accomplished by the following procedure: (1). A teflon-encased magnetic stirring bar, 4 gm of potassium persulfate, and 0.5 ml of 0.5 M phosphoric acid were placed in the combustion flask with the water sample to be analyzed. (2). The valves were attached to the combustion flask and the unit placed on the magnetic stirrer. The tubes from the carbon removal apparatus were attached to the unit and carbon dioxide-free air was passed over the samples for 30 minutes while the samples were rapidly stirred. The time necessary for removal of inorganic carbon dioxide was checked by attaching the combustion unit to the I-R anaylzer, and no detectable carbon was present after 15 minutes. For routine analysis, however, the samples were vigorously stirred for 30 minutes to insure complete removal. (3). The valves were tightly closed, the tubes were detached from the unit, and the flask placed in a steam autoclave at 10 psi, 115° C, for 30 minutes. Procedure for Measuring Carbon Dioxide from the Combustion of Organic Carbon. The carbon dioxide resulting from the combustion of organic carbon was measured in the following manner: (1). After the autoclave had been turned off and the pressure slowly reduced, the combustion unit was removed and placed in running tap water to hasten cooling the unit to room temperature (about 10 minutes). (2). The unit was placed in a water bath at 20 ± l ° C and attached to the carbon dioxide measuring system. (3). The carbon dioxide was removed by pumping gas through the KOH tube (re­quiring about 5 minutes with the large system volume of 5 liters, and less time with smaller volumes). (4). The valves on the KOH tube were closed and the combustion unit valves opened. The water sample was vigorously stirred until the carbon dioxide in the sample reached equilibrium with the carbon dioxide in the system. (5). The pump was turned off, and the reading on the analyzer meter was recorded. The amount of carbon dioxide or carbon in the system was calculated by using a standard curve. Further computations were unnecessary when the flask held the same Organic Carbon Levels in Some Aquatic Ecosystems volume of water as was used during calibration, and when the carbon dioxide was in equilibrium between the gas and liquid phases of the system. (6). Before the combustion unit was removed from the system, the valve connected to the manometer was opened and the pressure in the system noted. A low or negative pressure indicated a leak in the system or combustion unit. Pressures varied with differ­ent system volumes and with fresh and salt water samples. Possible Range of Measurement Using the Infrared Method. The permissible range of measurement of organic carbon concentrations using the 1-R method was relatively wide. The range was from 0.05 to 20 mg carbon. The low values were measured with the small system volume, the highest gain-control setting, and 250-ml samples. High con­centrations of organic carbon were measured with the large system volume and low gain setting. High concentrations were determined by using small samples. When this was done, the 250-ml sample volume was reached by adding double distilled water. It was necessary to use the 250-ml volume in order to maintain standardization. For special purposes, the system was modified to extend the range of measurement even further. Extremely high carbon values could be measured by using a larger system and the range of usefulness of the I-R method could be considered unlimited in that respect. For very large volumes, a higher pumping rate would have to be used to remove the carbon dioxide from the system in a reasonable length of time. The extent of the lower range was limited by the values obtained from the reagent blanks. The average blank value was 0.24 mg carbon (Table 1). Sampling Methods Used in Field Studies. All water samples were taken at a depth of approximately 0.5 m and care was taken to exclude surface film from the samples. The 250-ml samples were placed in a clean 500-ml Erlenmeyer flask and frozen within 30 minutes after they were collected by placing the flasks in a dry ice and alcohol bath. The tops of the flasks were covered with aluminum foil. All samples collected were frozen unless they could be analyzed within an hour after sampling. The frozen samples were analyzed within a week after collection. Duplicate samples were taken at each station. In the cases where only one value was reported, the duplicate sample was ruined by flask breakage or a failure in the pro­cedure. Exceptions are noted where the data are reported. River samples were obtained by lowering two 250-ml volumetric flasks clamped to the end of a pipe into the water from bridges over the rivers. Results EXPERIMENTS DESIGNED TO TEST THE 1-R METHOD Reagent Blanks and Known Compounds. To test the effectiveness of the I-R method of organic carbon analysis, blanks consisting of double distilled water and reagents were analyzed. The average blank value of 0.24 mg carbon ( 8 ± 0.02, N = 12) was sub­tracted from the result of each organic carbon analysis. The accuracy of the method was tested for effectiveness by analyzing compounds with a known carbon content. Dr. C. G. Skinner selected compounds of varying degrees of toughness for this analysis. The compounds were weighed on aluminum foil without drying and were placed in oxidation flasks with double distilled water. The water­insoluble compounds had a tendency to adhere to the walls of the flask above the water level and after oxidation could still be seen although the compounds in the water had Organic Carbon Levels in Some Aquatic Ecosystems disappeared. The results of these analyses (Table 1) indicate a 95% average recovery of carbon from the compounds tested. Chlorella Samples. Chlorella samples obtained from Dr. Jack Myers were also ana­lyzed. The results of Chlorella analyzed by the 1-R method were compared to results of Chlorella analyzed by other methods (Table 2). The Chlorella med had been freeze-dried and stored in vials containing nitrogen. Chlorella preserved in this fashion is very hydroscopic. The first analysis was made on a sample that had been previously opened and may have picked up moisture. For the last three analyses, a portion of a sample was used for which Dr. Myers had obtained a commercial elemental analysis. The results of the commercial analysis are reported in Table 2. Weighing the Chlorella samples was difficult as the samples rapidly gained weight while on the balance. This possibly contributed to the difference in values found in the last two samples. The discrepancy was small, and the analysis of Chlorella by the 1-R method agreed with other methods of analysis. TEXAS BAYS Data on organic concentrations in the waters of Texas bays and rivers are given in Figs. 2-5. Studies of the marine environment have shown that there is a low concentra­tion of organic matter in sea water. Reviewing the literature on the subject, Duursma (1960) reported that the range of organic matter in the open sea is 0.04 to 8 mg/liter. The values of organic matter reported in this investigation were from samples taken TABLE 1 Recovery of carbon from known compounds Compound mg compound added mg C added mg C reco,·ered per cent recovery Dextrose 8.21 ± .02 3.28 3.11 ± .05 95 10.69 ± .02 4.28 4.09 ± .05 96 7.65 ± .02 3.06 2.96 ± .05 97 Diphenylurea 2.41 ± .02 1.77 1.67 ± .05 94 3.71 ± .02 2.73 2.44 ± .05 89 5.37 ± .02 3.95 3.66 ± .05 93 Benzoic Acid 10.39 ± .02 7.15 7.06 ± .05 99 6.62 ± .02 4.56 4.46 ± .05 98 3.91 ± .02 2.69 2.53 ± .05 94 6-Mercaptopurine 5.18 ± .02 1.83 1.66 ± .05 91 3.75 ± .02 1.32 1.25 ± .05 95 6.80 ± .02 2.40 2.25 ± .05 93 Pregnane 4.89 ± .02 3.21 3.18 ± .05 99 4.63 ± .02 3.04 2.74 ± .05 90 5.30 ± .02 3.48 3.44 ± .05 99 DL Tryptophane 2.18 ± .02 1.41 1.37 ± .05 97 2.22 ± .02 3.04 1.34 ± .05 91 3.28 ± .02 3.48 2.01 ± .05 95 Pteridine 2.32 ± .02 1.17 1.11 ± .05 95 2.37 ± .02 1.19 1.17 ± .05 98 2.19 ± .02 1.10 1.00 ± .05 91 -­ X=95 standard error (S.E.) = 1 TABLE 2 Recovery of carbon from Chlorella by the I-R analysis method compared to two other methods of recovery. The first was a wet combustion method used by Corcoran and the other was from commercial elemental analysis I-R method Wet combustion 41.8% 41.6% 42.2% 43.5% 43.0% 37.7% 41.7% 42.2% I-R method Elemental analysis 49.1% 49.2% 47.1% 48.5% 46.1% off-shore in the Gulf of Mexico and in estuarine bays, not in the open sea. However, samples from Texas bays had a much higher organic content than samples from the Gulf of Mexico. Fox, Isaacs, and Corcoran (1952) reported that some off-shore water in California contained 20 mg carbon/liter, and Collier et al. ( 1953) reported high con­centrations in Galveston Bay, Texas. The samples analyzed contained dissolved and suspended organic matter. This was done in order to include all the organic matter in water. The few samples that were filtered (Table 4) show a high per cent of the total organic matter to be in dissolved and colloidal form. Although the percentage was high, it was lower than usually found in sea water (Duursma, 1960). The relatively high amount of particulate matter may TABLE 3 Analyses of samples Source of samples MgC/L *PUERTO RICO Brine pool where salt water was being ernporated for salt 118 124 Marine source water from Thalassia flat near shore outside a Mangrove Swamp 1.0 Marine water entering over the mud of a Mangrove Swamp (Rhizopora) 5.0 Marine water leaving a 'Mangrove Swamp 30.2 25.8 MISCELLANEOUS AREAS Laguna Madre Tamaulipas, Mexico; sampled May, 1961 51.6 53.6 Pond in Zilker Park, Austin, Texas; sampled April, 1962 69.1 73.2 Littlefield Fountain, University of Texas, Austin (on campus) ; sampled April, 1961 38.0 Aged sea water obtained from Port Aransas, Texas, July, 1959, and 2.2 kept in the dark in a glass carboy; analyzed November, 1961 2.5 2.4 2.5 2.6 Waller Creek at the University of Texas; 7.9 sampled April, 1961 8.1 Fresh water pond south of Aransas Pass, Texas; 90.0 sampled 10 May, 1960 105.0 • The samples were not frozen and were analyzed 4 lo 8 da~·s after they were taken, April 2-6, 1962. The six-day biological oxygen demand for the rainforest samples was 0.22 mg O:/liler (personal communication with Dr. H. T. Odum). have been due to the high populations of bacteria found in these bays (Oppenheimer and Jannasch, 1962). Sea water kept in a darkened glass carboy for over two years by Dr. Austin Phelps had 2.2 to 2.6 mg carbon/ liter. This value is much larger than those of previous reports Fie. 2. Organic carbon data in mg carbon per liter of water. Sabine Bay on the Texas-La. border, sampled 7 April, 1962. Galveston Bay, Texas, sampled 24 February, 1962. San Antonio and Aransas Bays, Texas sampled 10 March, 1962. Central coast area near Corpus Christi, Texas: Baffin Bay was sampled 23 April, 1960, the Gulf of Mexico was sampled 20 August, 1960, and the other samples were obtained 17-18 May, 1960. Organic Carbon Levels in Some Aquatic Ecosystems for the action of marine bacteria on organic matter in marine water, especially as a surface was available for growth (Zobell, 1946; Waksman, Carey, and Reuszer, 1933; and Rakestraw, 1947). The highest levels of organic carbon approached or exceeded 100 mg carbon/liter, and were found in samples from three areas: Baffin Bay, Texas (Fig. 2); a fresh water pond near Aransas Pass, Texas (Table 4); and in a man-made brine pool in Puerto Rico (Table3). TABLE 4 Organic carbon content of filtered samples Total carbon Dissolved• Dissolved* Source of sample mg C/ liter mg C/liler per cent Fresh water pond south of Aransas Pass, Texas; 90.0 55.0 61.0 sampled 15 May, 1960 105.0 67.0 64.0 Sea water from Aransas Pass, Texas; 2.6 1.3 50.0 sampled 20 August, 1960 1.4 0.9 64.0 Baffin Bay, Texas; 91.5 39.0 42.0 sampled 23 April, 1960 80.0 34.0 43.0 The samples were passed through a millipore type H-A filter (average pore size, 0.45 microns). Distilled waler, which had been passed through a filter, was used in place of the usual blank value. *Dissolved and colloidal fractions smaller than 0.45 microns. Values of approximate! y half of this concentration were found in samples taken from the Laguna Madre of Mexico (Table 3); the Lagua Madre of Texas (Fig. 2); from oil well bleed water near Corpus Christi, Texas (Fig. 3) ; and from a pond in Zilk er Park, Austin, Texas (Table 3). GULF OF MEXICO FIG. 4. Area of the Texas coast near Port Isa­ bel. Most of the samples were collected near the Brownsville Ship Channel. Samples were taken 31 March, 1962. The data are presented in mg ·carbon/liter. 0 Kllomerers Organic Carbon Levels in Some Aquatic Ecosystems No measurable amount of organic carbon could be found in samples from two springs in limestone formations (Fig. 5). If it is assumed that water entering the limestone formation contained some organic matter, then the question is raised as to what mech­anism removed it from the water before it emerges at the springs. Odum (1957) postu­lated that underground respiration removed organic matter from the water at Silver Springs, Florida. He supports this thesis with evidence that oxygen content of the water is higher when the flow of water is greater. Possible Formation and Fate of Organic .Matter. The major sources of dissolved organic carbon in water were primary production, runoff, and industrial or domestic wastes. The high values in oil well bleed water (Fig. 3) were an example of industrial waste. N f RIVER Organic Carbon Levels in Some Aquatic Ecosystems Each inhabited community along the two rivers that were sampled probably added domestic wastes to the rivers. One example of high concentrations of organic carbon probably due entirely to primary production was the pond sampled in Zilker Park, Austin, Texas. Water was piped into the artificial pond from Barton Springs, which had no measurable organic carbon. There was no drainage where organic matter could be added by runoff and the pond had no outlet. Water was added only to maintain the water lost by evaporation or seepage. Reduced flushing accompanied by evaporation may concentrate organic matter in· water. Baffin Bay, Mexican Laguna Madre, and the salt pool in Puerto Rico had little flushing and high concentrations of organic matter. High concentration of organic matter near 100 mg/liter was found in the pond south of Aransas Pass, Texas. At the time this pond was sampled, there was no visible water flowing into it and the narrow connection between it and Redfish Bay probably reduced flushing. Another factor contributing to high organic concentration in water was reduced community respiration. Respiration may be affected by high salt concentration or pos­sibly by domestic and industrial wastes. In theory, an unbalanced community metabo­lism is a necessary requirement for accumulating high concentrations of organic matter. The rate of organic matter increase from all sources must be higher than the rate of destruction and export. Probably both an unbalanced metabolism and a low flushing rate are necessary. Waste materials may drastically influence primary production in two ways: destroy­ing the producers by detrimental actions on the plants, and by stimulating· primary production with the addition of nutrients. Perhaps to a lesser extent, runoff may play a similar role. The relatively low organic concentrations in samples from the Llano and Colorado Rivers (Fig. 5) suggest that runoff did not add a great deal of organic matter to the water. Primary production and wastes may have been the major contributors to the increasing concentrations downstream. The high concentrations found in samples from the San Antonio River (Fig. 5) may have been due to domestic wastes from San Antonio, Texas, or from primary production stimulated by nutrients in the wastes. The increase in concentration of organic matter at the mouth of the Guadalupe River (Fig. 5) may have been due to bleed water or actual oil reaching the river from the large number of oil wells in that vicinity. The constant destruction of organic matter by microbes requires a constant influx if a high level of organic matter is maintained. Results of production and respiration measurements in the Texas bays by the diurnal-curve method (Odum and Wilson, 1962) show that the bays with rivers flowing into them often had a respiration rate higher than the rate of production. The difference must have been due to organic matter supplied by the rivers. Acknowledgments It is a pleasure to acknowledge the inspiration, assistance and encouragement given to all aspects of this work by Dr. H. T. Odum. This research was supported by the following grants to Dr. Odum: National Science Foundation #G 3978 and G 13160 on Ecological Microcosms; National Institutes of Health #WP 002 04 on Metabolism of Marine Bays of Texas ; and the Office of Naval Research NONR 375 ( 11), Project NR 104-435 on the Productivity of Texas Bays. Organic Carbon levels in Some Aquatic Ecosystems In addition to providing working space and the equipment for much of the work reported, Dr. Jack Myers' constructive criticisms and suggestions were invaluable. Or­ganic compounds used to test the accuracy of the infrared method were selected and provided by Dr. C. G. Skinner. Literature Cited Collier, A., S. M. Ray, A. W. Magnitsky, and I. 0 . Bell. 1953. Effect of dissolved organic substance on oysters. Fish. Bull. U.S. 54: 167-185. Duursma, E. K. 1960. Dissolved organic carbon, nitrogen and phosphorus in the sea. Netherlands J. Mar. Res. 1: 1-148. Fox, D. L., J. D. Isaacs, and E. F. Corcoran. 1952. Marine leptopal, its recovery measurement and distribution. J. Mar. Res. 11: 29-46. Odum, H. T. 1957. Trophic structure and productivity of Silver Springs, Florida. Ecol. Monogr. 27: 55-112. Odum, H. T., and R. F. Wilson. 1962. Further studies on respiration and metabolism of Texas bays 1958-1960. Puhl. Inst. Mar. Sci. Univ. Tex. 8: 23-55. Oppenheimer, C.H., and H. W. Jannasch. 1962. Some bacterial populations in turbid and clear sea water near Port Aransas, Texas. Puhl. Inst. Mar. Sci. Univ. Tex. 8: 56-60. Rakestraw, N. W. 1947. Oxygen consumption in sea water over long periods. J. Mar. Res. 6: 259-263. Waksman, S. A., C. L. Carey, and R. W. Reuszer. 1933. Marine bacteria and their role in the cycle of life in the sea, I. Biol. Bull., Woods Hole 65: 57-79. Wilson, R. F. 1961. Measurements of organic carbon in sea water. Limnol. & Oceanogr. 6(3): 259-261. Wilson, R. F. 1963. Studies of organic matter in aquatic ecosystems. Ph.D. Thesis, University of Texas, Austin. 112 p. Zobell, C. B., 1946. Marine microbiology. Chronica Botanica, Waltham, Massachusetts, 240 p. Seasonal Plankton Productivity in the Surf zone of a South Texas Beach1 WILLIAM N. McFARLAND2 Institute of Marine Science, The University of Texas Port Aransas, Texas Abstract Seasonal change in the oxygen metabolism of the microconstituents of surf water at Mustang Island, Texas were measured using a light-dark bottle method. The gross photosynthesis, net photosynthesis and respiration of plankton reached highest levels during summer and fall and lowest levels during winter. Respiration during summer averaged 1.05 g 0 2/m3 per day and was four times the average winter respiration. Net photosynthesis during summer averaged 0.99 g 0 2/m3 per day and was nearly three times the average winter rate. A net photosynthesis occurred throughout the year except during spring, when periodic bursts of high spring respiration coincided with large numbers of decapod larvae in the surf water. Seasonal change in temperature, salinity and beach water currents are also related to the seasonal change in plankton productivity. Introduction Sandy beaches that are subject to strong wave action constitute a considerable portion of the earth's shorelines. Sand beach environments can be distinguished biologically from other coastal environments, such as rocky coastlines, by the presence of infaunas as dominant resident populations and the virtual absence of macrophytes (Hedgpeth, 1957). Biological studies of sandy beaches have dealt primarily with the infaunas and the adaptations of species to the rigors of the environment. An extensive literature has ac­cumulated on the physiography of sand beaches and their biota (see Hedgpeth, 1957). The work of Koepcke and Koepcke (1952) on North Peruvian sand beach faunas con­siders the over-all ecology of the sand beach environment. Quantitative studies of the standing crop of organisms characteristic of sand beaches have been limited almost entirely to the molluscan infauna (Fitch, 1950; Loesch, 1957). Studies of the organisms present in the water mass are qualitative and mainly consider the relative seasonal abundance of fishes (Pearse, Humm and Wharton, 1942; Gunter, 1945; and Gunter, 1958). Other than descriptive material, little attention has been fixed on the plankton forms that are constantly swept over the sand beach environment by currents and tides. The food chains constructed by Koepcke and Koepcke (1952) indicate that a large per­centage of the molluscan infauna and Emerita depend on plankton and organic detritus, as do plankton-feeding fishes such as anchovies. In this paper data on salinity, temperature and the seasonal productivity of plankton are reported for the surfzone waters of the beach at Mustang Island, Texas. 1 Contribution No. 57 from the Marine Laboratory, Texas Game and Fish Commission, Rockport, Texas. 2 Present address: Department of Zoology, Cornell University, Ithaca, New York. Seasonal Plankton Productivity in the Sur/zone of a South Texas Beach The beach studied is oriented approximately along a northeast-southwest axis. A series of 10 sampling stations were set up at one-mile intervals along Mustang Island, beginning at Caldwell Pier, Port Aransas, and ending 10miles to the southwest. The Environment The Texas coastal plain is noted for its shallow seaward gradient (Shepard, 1950; Hedgpeth, 1953) and sharp drop-offs are not encountered in the surfzone (Fig. 1). Al­though the action of seasonal currents drastically alter the absolute physiography of the Texas beach, profiles below high tide levels (as indicated in Fig. 1) are maintained in a relative state of constancy. For this reason all samples of water were obtained from the first longshore-trough, where water depth varied from about two and one-half to three. and one-half feet during a normal tidal cycle. The distance offshore varied from about 80 to 150 feet. Strong longshore currents, either in a northward or southward direction, occur throughout the year and are related to the direction of prevailing winds. Thus, during spring and particularly summer, southerly winds create a northward set of the inshore currents, whereas during winter, northerly winds induce a southward longshore cur­rent. East by south-easterly winds, which occur frequently during all seasons, coincide with both northward and southward longshore currents. Under these circumstances, other factors, such as major hydrographic features of the inshore shelf waters probably interact with wind to determine the direction of longshore currents. No attempt was made to characterize the beach sediments or infauna; the data re­ported deal exclusively with salinity, temperature and plankton productivity, each of which is little affected by the substratum. Seasonal Salinity Patterns Salinity of the water from the first longshore trough was determined for each of the ten stations, whenever possible, on a weekly basis from October 13, 1959 through No­vember 9, 1960. Triplicate Mohr titrations were performed on each sample and the mean salinity recorded to the nearest 0.01 %0• Analysis of a series of samples of 30 %o gave a mean deviation of ± 0.02 %o and a maximum deviation of ± 0.06 %o (N = 9). HIGH TIDE LOW TIDE f:: 2nd LONGSHORE TROUGH lAJ lAJ ~2 I I­ 3 Cl. I st LONGSHORE TROUGH lAJ 0 4 0 50 100 DISTANCE FROM SHORE (FEET l FIG. 1. Typical beach profile south of Port Aransas, Mustang Island, Texas. Often a fringe pool is created in the first 30 feet of the surf. As one proceeds along the beach the bars and trnughs vary slighth-in their distance offshore. As a result, bars are not continuous and troughs intermingle. Seasonal Plankton Productivity in the Sur/zone of a South Texas Beach TABLE 1 Seasonal salinity and temperature records. Non-bracketed values are salinities in %0• Bracketed values are temperatures in degrees centigrade. Stations 1-10 represent one-mile intervals commencing at Caldwell Pier, Port Aransas, Texas and extend southward along Mustang Island Station Date 5 10 Mean Oct. 13, 1959 31.06 31.12 31.27 31.28 31.21 31.32 31.44 31.46 31.46 31.49 31.31 (29.2) (29.2) (29.2) (29.2) (29.2) (29.2) (29.2) (29.2) (29.2) (29.2) (29.2) Oct. 21, 1959 27.77 28.82 29.14 29.25 29.50 29.57 29.58 29.58 29.58 29.57 29.24 (24.6) (25.1 ) (25.1) (25.1) (25.1) (25.1) (25.1) (25.1 ) (25.1) (25 .1) (25.05) Oct. 31, 1959 30.00 30.62 30.72 30.60 30.62 30.56 30.72 30.60 30.67 30.72 30.58 (26.0) (26.0) (26.5) (26.5) (26.6) (26.6) (26.8) (26.9) (26.9) (26.9) (26.57) Nov. 11, 1959 30.98 30.96 30.99 31.10 31.16 31.12 31.12 31.09 30.98 30.94 31.04 (21.0) (21.1 ) (21.1) (21.1) (21.1) (21.1) (21. 2) (21.1) (21.1 ) (21.1) (21.10) Nov. 20, 1959 29.14 29.10 29.20 29.19 29.23 29.25 29.28 29.25 29.40 29.36 29.24 (16.5) (16.4) (16.3) (16.5) (16.4) (16.6) (16.8) (16.8) (16.8) (16.8) (16.59) Dec. I , 1959 31.24 31.24 31.37 31.48 31.50 31.48 31.52 31.48 31.83 31.91 31.51 (18.0) (18.1) (18.0) (18.1) (18.1) (18.3) (18.3) (18.3) (18.1) (18.1) (18.14) Dec. 7, 1959 31.28 31.26 31.32 31.32 31.30 31.30 31.32 31.30 31.45 31.43 31.33 (15.1) (15.1 ) (15.2) (16.1) (16.1) (16.1) (16.1) (16.1) (16.1) (16.1) (15.81) Dec. 11, 1959 33.19 33.26 33.26 33.26 33.26 33.30 33.30 33.30 33.30 33.34 33.28 (20.0) (20.0) (20.0) (19.8) (19.8) (19.8) (19.8) (19.8) (19.8) (19.8) (19.86) Dec. 22, 1959 31.86 31.97 32.02 32.17 32.04 31.97 32.00 32.00 32.00 32.04 32.01 (1 7.9) (17.9) (17.9) (18.0) (18.0) (18.0) (18.0) (18.1) (18.1 ) (18.1) (18.00) Jan. 7, 1960 29.61 29.59 29.39 29.30 28.99 29.60 28.83 28.60 28.50 28.58 29.10 (12.0) (12:0) (12.5) (12.4) (12.4) Cl2.4) (12.6) (13.1) (13.1) (13.0) (12.55) Jan. 12,1960 29.73 29.80 29.65 29.69 29.74 29.80 29.76 29.85 29.87 29.84 29.77 (18.0) (18.0) (17.9) (17.9) (18.0) (18.1) (18.1) (18.1) (18.1) (18.1) (18.03) Jan. 20, 1960 27.84 28.16 28.58 28.76 28.84 29.14 29.14 29.14 29.14 29.10 28.78 (13.0) (12.8) (12.8) (12.7) (1 2.5) (12.3) (12.2) (12.2) (12.o) (11.9) (12.44) Jan.29, 1960 29.20 31.28 31.25 31.26 31.26 31.38 31.25 31.04 31.02 31.06 31.00 (14.8) (14.8) (14.9) (14.8) (15.0) (15.0) (15.1 ) (15.2) (15.2) (15.2) (15.00) Feb. 5, 1960 32.79 32.88 32.94 32.92 33.09 33.09 33.09 33.24 33.13 33.28 33.05 (14.1) (14.1) (14.1) (14.0) (14.0) (14.0) (14.1) (13.9) (13.9) (13.9) (14.01) Feb. 18,1960 32.15 32.15 32.45 32.34 32.62 32.60 32.84 33.61 34.05 34.22 32.90 (16.1) (16.1 ) (16.1 ) (15.9) (15.9) (15.6) (15.2) (15.1) (15.1) (15.1) (15.62) Feb.26, 1960 30.24 31.32 31.67 31.77 31.84 32.80 32.93 33.50 32.90 33.06 32.20 (13.8) (13.9) (13.9) (13.8) (13.8) (13.7) (13.7) (13.7) (13.7) (13.7) (13.77) Mar. 4, 1960 24.77 29.39 29.76 29.81 29.93 29.95 30.00 30.04 30.09 30.13 29.39 (12.8) (12.9) (13.0) (13.1) (13.2) (13.3) (13.4) (13.3) (13.3) (13.3) (13.16) Mar.9, 1960 29.30 29.00 29.09 28.91 28.91 28.91 28.93 28.96 . 28.04 28.04 28.81 (13.5) (1 3.5) (13.5) (13.6) (13.7) (13.8) (13.8) (13.9) (13.9) (13.9) (13.71) Mar. 16, 1960 28.98 28.59 28.23 27.90 27.77 27.47 27.71 28.40 28.77 29.07 28.29 (15.6) (15.6) (15.6) (15.6) (15.7) (15.8) (15.7) (15.7) (15.6) (15.5) (15.64) Mar. 25, 1960 33.52 33.72 33.67 33.85 33.85 33.91 34.04 33.91 33.85 34.00 33.83 (16.7) (16.7) (16.7) (16.7) (16.7) (16.8) (16.7) (16.8) (16.8) (16.7) (16.73) Mar. 31, 1960 30.47 30.60 30.69 30.65 30.65 30.69 30.75 30.69 30.93 30.88 30.70 (20.5) (20.5) (20.6) (20.6) (20.7) (20.8) (20.8) (20.8) (21.0) (21.0) (20.73) Apr. 8, 1960 31.77 31.77 31.96 31.96 (20.0) (20.0) (20.0) (20.0) 32.20 32.62 (19.9) (19.8) 32.39 32.43 32.24 32.39 (19.7) (19.7) (19.7) (19.8) 32.17 (19.86) Apr. 13, 1960 32.94 32.96 32.99 32.96 (20.5) (20.5) (20.4) (20.4) 33.07 33.09 (20.4) ('20.4) 33.11 33.22 33.26 33.22 (20.5) (20.5) (20.3) (20.4) 33.08 (20.43) Apr. 19, 1960 31.41 31.50 31.80 32.75 (22.0) (22.0) (22.1) (22.1) 31.76 31.86 (22.1) (22.2) 31.86 31.86 31.97 32.00 (22.2) (22.3) (22.3) (22.3) 31.89 (22.16) Apr. 27, 1960 29.99 30.03 30.20 30.18 (26.0) (26.0) (26.0) (26.2) 30.25 30.18 (26.2) (26.2) 30.37 30.56 30.56 30.56 (26.3) (26.3) (26.3) (26.4) 30.29 (26.19) May5, 1960 27.17 27.26 27.30 27.49 (25.0) (25.0) (25.0) (25.0) 27.36 27.55 (25.0) (24.9) 27.55 27.83 27.96 28.05 (24.9) (24.6) (24.5) (24.5) 27.55 (24.84) May 13, 1960 32.45 32.41 32.40 32.45 (23.5) (23.5) (23.4) (23.4) 32.43 32.51 (23.3) ('23.3) 32.63 32.72 32.56 32.51 (23.3) (23.2) (23.2) (23.2) 32.51 (23.33) Seasonal Plankton Productivity in the Sur/zone of a South Texas Beach TABLE I-Continued Station Date 5 Mean 10 May 20, 1960 32.89 33.64 33.64 33.79 33.98 34.21 34.36 34.17 34.59 34.59 33.99 (26.0) (26.0) (26.1) (25.5) (25.5) (25.2) (25.2) (25.1) (25.0) (25.0) (25.40) May 28, 1960 32.43 32.56 32.89 32.98 33.18 33.43 33.43 33.42 33.49 33.51 33.13 (28.5) (28.5) (28.6) (28.7) (28.7) (28.7) (28.8) (28.8) (28.8) (28.9) (28.70) May 31, 1960 33.00 33.05 33.11 33.12 33.18 33.18 33.14 33.20 33.29 33.31 33.16 (28.8) (28.8) (28.9) (29.0) (29.0) (29.0) (29.1) (29.1) (29.1) (29.1) (28.99) June9, 1960 34.82 34.99 34.99 35.01 35.14 35.08 35.14 35.19 35.10 35.36 35.08 (32.0) (32.1) (32.1) (32.2) (32.2) (32.2) (32.3) (32.3) (32.4) (32.4) (32.22) June 16, 1960 35.49 35.64 35.68 35.64 35.68 35.75 35.68 35.82 35.80 35.82 35.70 (29.5) (29.51 (29.3) (29.3) (29.3) (29.5) (29.4) (29.5) (29.5) (29.5) (29.43) June 28, 1960 34.60 34.97 34.97 34.88 34.97 35.34 35.71 35.71 36.51 36.46 35.41 (30.2) (30.2) (30.4) (30.4) (30.5) (30.6) (30.6) (30.6) (30.8) (30.8) (30.51) July I, 1960 38.29 (32.5) 38.49 (32.5) 38.44 38.29 (32.5) (33.0) 38.29 (33.0) 38.68 (33.0) 37.52 (33.0) 38.29 (32.5) 38.49 (32.5) 38.49 (32.5) 38.33 ('32.70) July 1-1, 1960 35.95 (31.1) 36.18 (31.1) 36.34 36.18 (31.2) (31.3) 36.36 (31.5) 36.53 (31.4) 36.40 (31.5) 36.64 (31.5) 36.62 (31.4) 36.35 (31.5) 36.36 (31.35) July 22, 1960 37.62 (31.1) 37.54 (31.2) 37.66 37.64 (31.2) (31.4) 37.77 (31.4) 37.73 (31.5) 37.66 (31.5) 37.66 (31.7) 37.66 (31.7) .. .... . . (31.8) 37.66 (31.45) July 28, 1960 36.88 (34.0) 36.61 (33.9) 36.84 36.86 (33.9) (33.8) 36.78 (33.8) 37.01 (33.6) 36.90 (33.6) 36.94 (33.6) 37.01 (33.5) 36.97 (33.5) 36.88 (33.72) Aug. 8, 1960 37.01 (29.8) 37.04 (29.8) 37.08 37.12 (29.8) (29.6) 37.08 (29.5) 37.04 (29.4) 37.12 (29.4) 37.04 (29.3) 37.08 (29.3) 37.03 (29.3) 37.06 (29.52) Aug. 17, 1960 38.61 (31.0) 38.61 (31.0) 38.67 38.73 (31.0) (31.2) 38.75 (31.2) 38.82 (31.2) 38.82 (31.3) 38.79 (31.3) 38.82 (31.4) 38.81 (31.4) 38.74 (31.20) Aug. 25, 1960 37.45 (29.8) 37.38 (29.8) 37.48 37.44 (29.8) (29.8) 37.50 (29.8) 37.52 (29.9) 37.52 (29.9) 37.46 (29.9) 37.50 (29.9) 37.54 (30.0) 37.49 (29.86) Sept. 1, 1960 36.45 (31.0) 36.57 (31.0) 36.69 36.77 (31.0) (31.0) 36.85 (31.2) 36.87 (31.2) 36.89 (31.3) 37.03 (31.3) 37.09 (31.4) 37.09 (31.4) 36.83 (31.18) Sept. 8, 1960 33.40 33.58 33.60 33.72 33.70 33.74 33.80 33.98 34.04 34.08 33.76 (29.8) (29.8) (29.8) (29.9) (29.9) (29.9) (29.9) (30.0) (30.0) (30.0) (29.90) Sept. 16, 1960 30.69 (28.8) 30.73 (28.8) 31.02 31.06 (28.9) (28.9) 31.00 (28.9) 30.63 (28.9) 30.79 (29.0) 30.75 (29.0) 30.73 (29.0) 30.89 (29.0) 30.83 (28.92) Sept. 28, 1960 31.06 (27.5) 31.10 (27.5) 31.21 31.25 (27.3) (27.3) 31.39 (27.2) 31.37 (27.2) 31.25 (27.2) 31.39 (27.1) 31.45 (27.0) 31.43 (26.9) 31.29 (27.22) Oct. 7, 1960 34.02 34.10 34.16 34.20 34.12 34.20 34.16 34.20 34.22 34.37 34.18 (28.2) (28.2) (28.2) (28.4) ("28.4) (28.5) (28.6) (28.6) (28.6) (28.7) (28.44) Oct. 14, 1960 36.48 32.71 32.59 32.73 32.63 32.63 32.69 32.75 32.81 32.83 33.09 (28.0) (28.0) (28.C 28.2) (28.2) (28.2) (28.3) (28.4) (28.4) (28.5) (28.22 ) Nov. 9,1960 31.11 31.24 31.28 31.26 31.42 31.34 31.28 31.36 31.44 31.42 31.32 (24.8) (24.6) (24.4) (24.2) (24.0) (24.0) (24.0) (23.9) (23.9) (23.9) (24.17) The mean salinity for each station and the average salinity of all 10 stations are re­corded in Table 1. Seasonal variations of salinity are apparent (Fig. 2) and as expected (Gunter, 1958) , highest salinities occurred in July and August and lowest salinities in the winter and spring months. Abrupt fluctuations in salinity probably represent the mix­ing of brackish waters from the Texas bays with gulf shelf water. As a rule, outflow from the south Texas bays through Aransas Pass, Port Aransas is directed southward and sets on the Mustang Island beach 2 to 5 miles south of the pass (as indicated by drift bottles released in the mouth of the pass). Since northerly winds favor a southward longshore current, bay and gulf waters commonly mix along the beach and result in lowered sa­linities during winter. In contrast, during summer when longshore currents are often directed to the north, mixing of bay and gulf waters occurs offshore and, as a result, beach salinities along Mustang Island are more characteristic of Gulf of Mexico water. Seasonal Plankton Productivity in the Sur/zone of a South Texas Beach 81 0 0 0 N D J F 1959 TIME OF YEAR FrG. 2. Seasonal changes in temperature and salinity of the surf south of Port Aransas, Mustang Island, Texas. Direction of longshore current is to a large extent the result of prevailing winds. Thus a northward set of current results from southerly winds. Salinities and temperatures are the averages of 10 samples collected at one-mile intervals along the beach. Raw data are recorded in Table L However, during summer, southward longshore currents occur sporadically during periods of easterly winds. Hence, mixing of bay and gulf waters may occur during periods of high bay salinities; as a result beach salinities may exceed normal values for offshore gulf waters (Fig. 2, see July and August). Examination of the data for each sampling statio ~eveals that horizontal linear sa­linity gradients along the beach were prevalent only during the months of January, Feb­ruary, March, April and May. Salinity gradients seldom exceeded 1 %0, with highest values toward the south. Thus they are indicative of the mixing of bay and gulf waters. On two occasions reversed linear gradients were recorded (Table 1, January 7 and March 9, 1960). These data are difficult to interpret since on both occasions the longshore currents were directed southward. Salinity gradients were not encountered during the months of June, July, August, September, October, and November, with the exception of 6 collections : 2 in October 1959, 1 in November 1959, 1 in July 1960, and 2 in September 1960. Intermixing of bay and gulf waters on the open beach south of Aransas Pass ChanneL as judged from salinities, occurs in late winter and spring, with only sporadic mixing at other times of the year. The over-all seasonal change in salinity (Fig. 2) shows a steady climb to high values beginning in May and probably reflects the high rate of evaporation which occurs during summer. The abrupt decline of salinities during September can be related to heavy rains and run-off which occurred during late summer and fall. The lowest salinities were re­ Seasonal Plankton Productivity in the Sur/zone of a South Texas Beach TABLE I-Continued Station Date 5 10 Mean May 20, 1960 32.89 (26.0) 33.64 (26.0) 33.64 33.79 (26.1) (25.5) 33.98 (25.5) 34.21 (25.2) 34.36 (25.2) 34.17 (25.1) 34.59 (25.0) 34.59 (25.0) 33.99 (25.40) May 28, 1960 32.43 (28.5) 32.56 (28.5) 32.89 32.98 (28.6) (28.7) 33.18 (28.7) 33.43 (28.7) 33.43 (28.8) 33.42 (28.8) 33.49 (28.8) 33.51 (28.9) 33.13 (28.70) May 31, 1960 33.00 (28.8) 33.05 (28.8) 33.11 33.12 (28.9) (29.0) 33.18 (29.0) 33.18 (29.0) 33.14 (29.1) 33.20 (29.1) 33.29 (29.1) 33.31 (29.1) 33.16 (28.99) June9, 1960 34.82 (32.0) 34.99 (32.1) 34.99 35.01 (32.1) (32.2) 35.14 (32.2) 35.08 (32.2) 35.14 (32.3) 35.19 (32.3) 35.10 (32.4) 35.36 (32.4) 35.08 (32.22) June 16, 1960 35.49 (29.5) 35.64 (29.5) 35.68 35.64 (29.3) (29.3) 35.68 (29.3) 35.75 (29.5) 35.68 (29.4) 35.82 (29.5) 35.80 (29.5) 35.82 (29.5) 35.70 (29.43) June 28, 1960 34.60 (30.2) 34.97 (30.2) 34.97 34.88 (3o.4) (30.4) 34.97 (30.5) 35.34 (30.6) 35.71 (30.6) 35.71 (30.6) 36.51 (30.8) 36.46 (30.8) 35.41 (30.51) July 7, 1960 38.29 (32.5) 38.49 (32.5) 38.44 38.29 (32.5) (33.0) 38.29 (33.0) 38.68 (33.0) 37.52 (33.0) 38.29 (32.5) 38.49 (32.5) 38.49 (32.5) 38.33 ('32.70) July 14, 1960 35.95 (31.1) 36.18 (31.1) 36.34 36.18 (31.2) (31.3) 36.36 (31.5) 36.53 (31.4) 36.40 (31.5) 36.64 (31.5) 36.62 (31.4) 36.35 (31.5) 36.36 (31.35) July 22, 1960 37.62 (31.1) 37.54 (31.2) 37.66 37.64 (31.2) (31.4) 37.77 (31.4) 37.73 (31.5) 37.66 (31.5) 37.66 (31.7) 37.66 (31.7) ·· ······ (31.8) 37.66 (31.45) July 28, 1960 36.88 (34.0) 36.61 (33.9) 36.84 36.86 (33.9) (33.8) 36.78 (33.8) 37.01 (33.6) 36.90 (33.6) 36.94 (33.6) 37.01 (33.5) 36.97 (33.5) 36.88 (33.72) Aug. 8, 1960 37.01 (29.8) 37.04 (29.8) 37.08 37.12 (29.8) (29.6) 37.08 (29.5) 37.04 (29.4) 37.12 (29.4) 37.04 (29.3) 37.08 (29.3) 37.03 (29.3) 37.06 (29.52) Aug. 17, 1960 38.61 38.61 38.67 38.73 38.75 38.82 38.82 38.79 38.82 38.81 38.74 (31.0) (31.0) (31.0) (31.2) (31.2) (31.2) (31.3) (31.3) (31.4) (31.4) (31.20) Aug. 25, 1960 37.45 (29.8) 37.38 (29.8) 37.48 37.44 (29.8) (29.8) 37.50 (29 .8) 37.52 (29.9) 37.52 (29.9) 37.46 (29.9) 37.50 (29.9) 37.54 (30.0) 37.49 (29.86) Sept. 1, 1960 36.45 (31.0) 36.57 (31.0) 36.69 36.77 (31.0) (31.0) 36.85 (31.2) 36.87 (31.2) 36.89 (31.3) 37.03 (31.3) 37.09 (31.4) 37.09 (31.4) 36.83 (31.18) Sept. 8, 1960 33.40 (29.8) 33.58 (29.8) 33.60 33.72 (29.8) (29.9) 33.70 (29.9) 33.74 (29.9) 33.80 (29.9) 33.98 (30.0) 34.04 (30.0) 34.08 (30.0) 33.76 (29.90) Sept. 16, 1960 30.69 30.73 31.02 31.06 31.00 30.63 30.79 30.75 30.73 30.89 30.83 (28.8) (28.8) (28.9) (28.9) (28.9) (28.9) (29.0) (29.0) (29.0) (29.0) (28.92) Sept. 28, 1960 31.()6 (27.5) 31.10 (27.5) 31.21 31.25 (27.3) (27.3) 31.39 (27.2) 31.37 (27.2) 31.25 (27.2) 31.39 (27.1) 31.45 (27.0) 31.43 (26 .9) 31.29 (27.22) Oct. 7, 1960 34.02 34.10 34.16 34.20 34.12 34.20 34.16 34.20 34.22 34.37 34.18 (28.2) (28.2) (28.2) (28.4) ('28.4) (28.5) (28.6) (28.6) (28.6) (28.7) (28.44) Oct. 14, 1960 36.48 32.71 32.59 32.73 32.63 32.63 32.69 32.75 32.81 32.83 33.09 (28.0) (28.0) (28.( 28.2) (28.2) (28.2) (28.3) (28.4) (28.4) (28.5) (28.22 ) Nov. 9,1960 31.11 31.24 31.28 31.26 31.42 31.34 31.28 31.36 31.44 31.42 31.32 (24.8) (24.6) (24.4) (24.2) ('24.0) (24.0) (24.0) (23.9) (23.9) (23.9) (24.17) The mean salinity for each station and the average salinity of all 10 stations are re­corded in Table 1. Seasonal variations of salinity are apparent (Fig. 2) and as expected (Gunter, 1958) , highest salinities occurred in July and August and lowest salinities in the winter and spring months. Abrupt fluctuations in salinity probably represent the mix­ing of brackish waters from the Texas bays with gulf shelf water. As a rule, outflow from the south Texas bays through Aransas Pass, Port Aransas is directed southward and sets on the Mustang Island beach 2 to 5 miles south of the pass (as indicated by drift bottles released in the mouth of the pass). Since northerly winds favor a southward longshore current, bay and gulf waters commonly mix along the beach and result in lowered sa­linities during winter. In contrast, during summer when longshore currents are often directed to the north, mixing of bay and gulf waters occurs offshore and, as a result, beach salinities along Mustang Island are more characteristic of Gulf of Mexico water. Seasonal Plankton Productivity in the Sur/zone of a South Texas Beach 81 0 0 36 z TEMPERATURE 32 w a:: :::) 28 I­ ~ ­ I-32 z_J 30 ' DIRECTION OF '(}:, 28 / LONGSHORE CURRENT 26 L..!==N~==~s:;::!!!IN~l==;::::===~s====:;:::=:::=;:::~~==::!:::::;:::===;:::===:;N!::::::==:;:===::::;::==='l.......,.~ 0 N D J F J J A s 0 N 1959 1960 TIME OF YEAR Frc. 2. Seasonal changes in temperature and salinity of the surf south of Port Aransas, Mustang Island, Texas. Direction of longshore current is to a large extent the result of prevailing winds. Thus a northward set of current results from southerly winds. Salinities and temperatures are the averages of 10 samples collected at one-mile intervals along the beach. Raw data are recorded in Table l. However, during summer, southward longshore currents occur sporadically during periods of easterly winds. Hence, mixing of bay and gulf waters may occur during periods of hjgh bay salinities; as a result beach salinities may exceed normal values for offshore gulf waters (Fig. 2, see July and August). Examination of the data for each sampling statio ~eveals that horizontal linear sa­linity gradients along the beach were prevalent only during the months of January, Feb­ruary, March, April and May. Salinity gradients seldom exceeded 1 %0, with highest values toward the south. Thus they are indicative of the mixing of bay and gulf waters. On two occasions reversed linear gradients were recorded (Table 1, January 7 and March 9, 1960). These data are difficult to interpret since on both occasions the longshore currents were directed southward. Salinity gradients were not encountered during the months of June, July, August, September, October, and November, with the exception of 6 collections: 2 in October 1959, 1 in November 1959, 1 in July 1960, and 2 jn September 1960. Intermixing of bay and gulf waters on the open beach south of Aransas Pass Channel, as judged from salinities, occurs in late winter and spring, with only sporadic mixing at other times of the year. The over-all seasonal change in salinity (Fig. 2) shows a steady climb to high values beginning in May and probably reflects the high rate of evaporation which occurs during summer. The abrupt decline of salinities during September can be related to heavy rains and run-off which occurred during late summer and fall. The lowest salinities were re· Seasonal Plankton Productivity in the Sur/zone of a South Texas Beach corded in January, March and April and, as indicated by Gunter (1958), can be corre­lated also with increased rainfall and run-off. Seasonal Temperature Patterns Mean water temperatures for the 10 sampling stations along the beach do not show such abrupt changes during the year when compared to changes in salinity (Fig. 2). Temperature of the water in the surfzone parallels seasonal changes in insolation, but also is directly affected by ambient air temperatures. As Gunter (1958) indicated for this beach, water temperatures lag behind changes in ambient air temperatures, particularly during periods of abrupt weather changes. Lowest temperatures were encountered during January and February and correlate with the passage of strong cold fronts from the north. Longshore temperature gradients were not well developed (Table 1). When they did occur, differences did not exceed 1°C and were as often oriented up the beach as down the beach with no apparent seasonal pattern (e.g., January 7 and January 20, 1960; August 8 and August 17, 1960). Seasonal Planktonic Respiration and Photosynthesis METHOD Estimation of planktonic metabolism has been measured most often by a light-dark bottle method (Gaarder and Gran, 1927) wherein changes in the oxygen content of water with time are used as a basis for calculation of respiration and photosynthetic rates. Al­though the method has inherent disadvantages (Steeman-Nielsen, 1952; Ryther and Vaccaro, 1954; Vacarro and Ryther, 1954; and Ryther, 1956), its simplicity lends the technique to quick estimation of planktonic metabolism for most waters. Two major objections are: (1) that enclosure of plankton in a bottle may affect metabolism and (2) that the surface of the bottles provides an enlarged area for bacterial proliferation which may affect oxygen levels. Short term sampling experiments by Ragotzkie (1959), however, indicated that respiration of plankton from estuarine waters in dark bottles was constant over a 36-hour period and suggest that enclosure of plankton, at least for short periods, should not seriously bias resulting estimates of metabolism. Estimation of plankton production in the surfzone water along Mustang Island beach required minor modification of the light-dark bottle method. The constant agitation of the water and its contained plankton by wave action suggested that agitation of the sam­ple bottles would provide more realistic results. To accomplish simulated surf motion in the samples, a bottle holder was constructed which accommodated 3 dark bottles and 3 light bottles (Fig. 3). Buoyancy and stability were provided by 4 steel crossarms which were directed upward at a 45° angle from the wood bottom. Floats at the tips of the crossarms were adjusted in size until the device had positive buoyancy. The entire appara­tus was positioned in the water at an appropriate depth by tying it to a Danforth anchor. Tidal fluctuations varied from about one to one and one-half feet. Depth of the bottle holder was adjusted so the light bottles were approximately six inches beneath the sur­face during low tide. The apparatus rocked shoreward as each wave passed and seaward with outgoing water movements. As a result, agitation of the plankton enclosed in the bottles was proportional to surf action on any given sampling day. Seasonal Plankton Productivity in the Sur/zone of a South Texas Beach Frc. 3. Light.dark bottle holder used to simulate surf motion. The rope is tied to a sand anchor. Water motion rocks the cage to and fro in proportion to wave action. Floats buoy the apparatus and orient the light bottles at the top of the cage toward the surface. Dissolved oxygen was measured by the Pomeroy-Kirschman sodium azide modifica­tion of the Winkler method (Faber, et al. 1955). Sample bottles were 125 ml capacity. Throughout the entire period sampling was begun between llOO and 1300 and ended at the same time on the following day. Results for the year of sampling are recorded in Table 2. Data represent samples collected from the first longshore trough between stations 3 and 4, lying 2 to 3 miles south of Caldwell Pier, Port Aransas. Initial oxygen samples and the dark and light bottles were filled by siphoning from a 5-gallon glass vessel after the water had been stirred and allowed to stand for 5 minutes. In spite of the attempt to equalize oxygen values at the start, considerable variation occurred on occasion (see con­fidence intervals for start bottles, Table 2). The mean coefficient of variance for titration of a constant standard was 0.96 per cent (7 triplicate subsamples of saturated distilled water), whereas the mean coefficients of variance for initial oxygen, light bottle, and dark bottle samples were 2.17, 2.19 and 1.51 per cent respectively. Variance for field data was approximately twice the titration error of about 1 per cent. RESPIRATION Seasonal changes in plankton respiration and photosynthesis appear to follow a dis­tinct pattern (Fig. 4). Respiration (R) maintained a low level from late November through mid-March and April. Bursts of high respiration occurred during late March and the month of May. High spring respiration can be correlated with the initial rise in water temperature from the low temperatures of January-February. However, examination of the seasonal salinity curves indicate that the high respiration during March and May is correlated with sudden large increases in salinity of the beach water (Fig. 2). The in­creased salinity can be attributed in part to the influx of gulf water on the beach resulting from prevailing wind direction (see Fig. 2 and Table 1). This suggests that high respira­ Seasonal Plankton Productivity in the Surf zone of .a South Texas Beach TABLE 2 Seasonal oxygen values for start bottles and 24-hour dark and light bottles from samplings of the surf water at Mustang Island, Texas . Data represent mean oxygen values and the 95% confidence limits expressed in mg oxygen per liter. Date of sampling Start bottles Dark bottles Light bottles mean ± 95% CI meao ± 95% CI mean± 95% Cl Oct. 13, 1959 Oct. 23, 1959 Nov. 3,1959 Nov. 12, 1959 Nov. 19, 1959 Nov. 23, 1959 Dec. 2, 1959 Dec. 8, 1959 Dec. 18, 1959 7.30 8.57 8.39 8.54 9.27 8.57 7.82 8.08 8.72 0.30 0.11 0.26 0.60 0.22 0.17 0.22 0.22 0.11 6.36. 6.66. 1.30• 7.77 8.89. 8.38 7.35 7.83 8.41" 0.17 1.03 0.52 0.26 0.11 0.39 0.26 0.26 0.11 7.53 8.79 8.76 8.38 9.62 9.03. 8.57. 8.ss• 9,59• 0.34 0.22 0.30 0.13 0.30 0.22 0.13 0.31 0.46 Jan. 7,1960 Feb. 18, 1960 Mar. 2, 1960 9.57 7.34 8.83 0.51 0.06 0.19 9.40 7.07° 8.68 0.09 0.19 0.13 9.24 7.52 9.23 0.52 0.52 0.56 Mar. 16, 1960 Mar. 30, 1960 Apr. 13, 1960 Apr. 27, 1960 May 12, 1960 May31, 1960 June 16, 1960 9.28 IO.SO 7.66 7.21 10.00 9.12 7.03 0.19 0.25 0.11 0.25 0.06 0.53 0.13 9.06 8.09* 7.49 6.95 7.67. 5,79• 6.51* 0.09 0.04 0.13 0.17 0.99 0.22 0.04 9.26 9.76. 8.04. 7.50 9.69 6.56. 7.51 0.56 0.43 0.22 0.52 1.25 0.60 0.39 July 1, 1960 July 16, 1960 July 29, 1960 Aug. 17, 1960 Sept. 6, 1960 Sept.20,1960 7.22 6.41 7.16 8.71 9.83 9.84 0.06 0.36 0.30 0.31 0.45 0.45 6.43. 4.91• 6.4o• 6.73. 8.81• 8.68. 0.22 0.30 0.09 0.09 0.22 0.43 7.9s• 7.63. 8.59. 7.8o• 11.32* 13.03. 0.52 0.43 0.86 0.34 0.56 0.65 Oct. 6, 1960 Oct. 24, 1960 10.50 10.68 0.64 0.21 9,59• 9.42· 0.17 0.90 12.21 • 13.29. 0.69 l.56 *-Difference from start bottle 95% CI signi6cant. tion during spring is related to spring pulses and breeding of gulf plankton, rather than to an effect of plankton from the large Texas bay systems. Inclusion of summer and late faJI respiration values for June through mid-November yields a mean summer-fall respiration of 1.05 g 0 2/ m3 per day (SE= ± 0.005 g). Ex­cluding the high spring respiration, similar treatment of data for late faJI through spring yields a mean respiration of 0.26 g 0 2/m3 per day (SE= ± 0.007 g). Thus, on the average, summer-fall respiration exceeded winter respiration by a fac tor of four (Student's -t = 34.0, where t<. 995 ) = 2.65). PHOTOSYNTHESIS Net photosynthesis (Pn) varied throughout the year, but tended to be low in the late fall of 1959 and the winter-spring period of 1960, and was highest during the summer and early fall of 1960 (Fig. 4) . Of the total of 27 light bottle samples for net photosyn­thesis, 15 are significantly different from the initial oxygen samples (Table 2). The net photosynthesis values for October 1959 are quite low compared to similar values for October 1960 and indicate high variability from year to year. Combination of the summer and early fall net photosynthetic rates gives a mean summer-fall Pn of 0.99 g 02/m3 per day (SE= ± 0.039 g) . Similar treatment of the late fall, winter, and spring values yields a mean Pn of 0.36 g 0 2/m3 per day (SE= ± 0.004 Seasonal Plankton Productivity in the Sur/zone of a South Texas Beach >­ <( 0 ' er: w (PN) 2 I- w ::;; '=" CD :::> u ' z w <..? >­ x 0 (f) ::;; <( er: <..? (PG) -l+--0N~,-DJ~.--F--r~M~,--J-,.~A~.---s--,~o---j ~.,....--~.---~.---A--,~MJ~.-­ 1959 1960 TIME OF YEAR FIG. 4. Seasonal plankton production in the surf south of Port Aransas, Mustang Island, Texas, as ob· tained by the light-dark bottle method. Solid vertical bars represent the 95% confidecne intervals of the means, which are represented by the thin horizontal lines. Raw data are presented in Table 2. g). Summer-fall net photosynthetic rates exceeded the winter-spring rates by a factor of 2.75 (Student's -t = 16.14, where t(.995 ) = 2.65). Associated with the high respiration rates during spring months and the highest sum­mer rate are corresponding low photosynthetic rates that are insufficient to balance the respiration of the plankton. On a few occasions, P n was negative during winter months (Fig. 4). Seasonal gross photosynthesis (Pg), the algebraic sum of Rand P0 , approached a maximum in the late summer and early fall of 1960. Seasonal Plankton Productivity in the Sur/zone of a South Texas Beach OXYGEN LEVELS IN THE SURFZONE Oxygen saturation values reveal that the surf water is most often supersaturated with oxygen or close to the 100% saturation level (Fig. 5) ; the values represent only the time period between 1100-1300 hours and it is not known if supersaturation declines during the night. Interestingly, the highest degree of supersaturation (about 170%) occurred in late summer and early fall of 1960, the seasonal periods when temperatures and sa­linities were at a maximum (Table 1; Fig. 2). The high summer supersaturation of the water with oxygen can be correlated with the high rates of net photosynthesis that oc­curred during this period (Fig. 4), but the peaks associated with March and May are more difficult to equate. The latter coincided with high rates of respiration for March and May, but since net photosynthesis was negative during this time undersaturation or, more likely, saturation of the water with respect to oxygen would seem more probable. Because the spring season is associated with major changes in the direction of prevailing winds and the associated influx of gulf water on the beach, and the general increase in temperature and salinity, these supersaturation peaks may be the result of physical processes. Alternatively, the high oxygen levels may result from photosynthetic activity of plankton in open gulf water before the water reaches the beach. This alternative would necessitate either a destruction of phytoplankon or a depression of photosynthesis in the surf environment since P n was low (Fig. 4). Unfortunately, the cause of spring super- z 0 f­ <( a: :J ~ (f) N 0 ~ a: w f­ _J N ' 0 <..? ~ 180 160 140 120 100 80 0 12 10 8 6 4 2 0 Fie. 5. Texas. The high degree of supersaturation during summer and fall coincides with high net plankton photosynthesis in the surf. The supersaturation peaks in spring coincide with negligible or negative net photosynthesis and remain unexplained. "'-._1003 SATURATION LINE N D J F M A M J J A s 0 ACTUAL 02 VALUES P-, / , ,0--0 I '(\ , ,o---0' I (f I ' / ---6 ' / o--Q, ff ' Q'/ CALCULATED 0 N D J F M A M J J A s 0 1959 1960 TIME OF YEAR Seasonal changes in the oxygen content of the surf south of Port Aransas, Mustang Island, ,Seasonal Plankton Productivity in the Sur/zone of a South Texas Beach saturation is obscure. The high summer oxygen levels most probably result from the high net photosynthesis determined for the period. Large concentrations of the blue green alga, Trichodesmium, were observed throughout this period and correlate with the high net photosynthesis. Net Plankton Abundance A total of 14 plankton hauls were made from March 9, 1960 through October 19, 1960. Identifications were made only to generalized types, and the number of specimens per cubic meter of water were calculated. Since the data are scanty, little can he said about absolute numbers of net plankton present. However, the data do reveal gross seasonal fluctuations in abundance and types, Table 3) . The largest total number of net plankton per cubic meter of water occurred in March, with lesser numbers present throughout the summer. Counts for September and October showed increases, hut not to the levels of abundance attained during March (Table 3) . The March peak is associated with large numbers of crab and shrimp larvae, which become less abundant in summer. The bulk of the April, May, and June populations is comprised of copepods. July and August are characterized by the virtual absence of net plankton from the surf. During this period water clarity is at a maximum. The Septem­ber and October peaks are caused primarily by copepods, with both mysids and chaetog­naths relatively abundant. Over-all, there appears to be a shift from a spring, decapod larval type plankton to a copepod plankton. In late summer and early fall, this cope­pod abundance increases along with mysids and chaetognaths. Unfortunately, winter samples are not available. Discussion The foremost results of the study are the seasonal fluctuations of variables wherein biological factors, represented by plankton metabolism, reach their highest levels in summer and their lowest levels in winter. Other studies on the biota of the beach at Mus­tang Island show similar fluctuations. The abundance of fishes on the Mustang Island beach also varies seasonally (Gunter, 1958; McFarland, 1963); the greatest abundance of fishes occurs in summer, declines in late summer and fall, and is lowest during late fall and winter. Loesch (1957) reported that Donax reached its greatest abundance on the beach during June and then declined gradually until fall. The abundance of both fishes and infauna (primarily Donax) on the Mustang Island beach is considerable, at least, through the summer. Certainly Donax and, to a degree, many of the fishes, such as the genera Harengula, Anchoa, Brevoortia and Mugil, must depend on plankton for food. Whether the availability of plankton is sufficient to meet their dietary needs is quantiatively unanswerable at this time. The correlation of plank­ton metabolism peaks (Pg) with the greatest abundance of fishes and Donax suggest that plankton serve as a primary food source to the higher trophic levels. The average values for both summer-fall and winter-spring respiration and photo­synthesis indicate that photosynthesis is usually in excess (Pg/R = 2.0). The average summer-fall value for respiration (R = 1.05 g 0 2/ m3 per day) and net photosy'nthesis (Pn = 0.99 g 0 2/m3 per day) are somewhat lower than a July 1957 value reported for co co TABLE 3 \./) Seasonal changes in net plankton during, spring, summer and the fall of 1960. Nonbracketed values are the average numbers of individuals per cubic meter of ~ water. Bracketed values are the ranges for replicate samples. Each mean represents 4 samples. The sample for August 17, 1960 represents only 2 samples. 0 ;:l ~ ~ General lype of animal Mar. 9 Mar. 16 Mar. 23 Apr. 13 May 13 May 31 Date, 1960 June 17 J uly 16 July 29 Aug.17 Sept. 6 Sept. 20 Oct. 6 Oct. 19 ....... >l ;:l ...... Comb jellies 0.3 (0-1.0) 0.2 (0-0.6) 1.9 (0-3.9) c ;:l ~ Veliger larvae 1.0 0.3 .... 0 (0--2.1) (0--0.9) ~ i;:: '"' Bryozoa ...."'· ~ Chaetognatha 3.6 16.3 ~· Mysids 0.2 (0--0.8) 0.8 (0-2.1) 1.3 (1.0--1.5) 5.0 (3.1-6.4) (2.8-4.1) (9.4-27.3) s· ........ C1> Isopods \./) i;:: Amphi pods 0.7 9.8 (0--2.8) (9.5-16.6) -."::!.. "' 0 ;:l Copepods 1.2 (0-4.0) 19.7 15.7 3.9 7.8 (1.3-42.1) (8.6-26.9) (2.3-6.6) (0.5-8.0) 0.7 (0.5-0.8) 0.3 (0-1.0) 41.3 (27.0--67.0) 5.5 34.0 (2.8-7.6) (25.5-38.7) C1> ..Q.. >l Shrimp larvae 4.2 (2.2-7.7) 5.9 (0--13.0) 2.1 (0.8-3.6) 0.2 (0--0.5) 1.3 (0-4.0) ~ ~ Crab larvae 79.1 146.5 5.9 0.4 0.9 0.1 0.9 .... (34.0--129.4) (19-326.0) (1.4-12.5) (0-0.7) (0--2.3) (0--0.4) (0-2.0) '"-3 C1> Fish larvae 33.2 (7.4-97.0) 4.5 (0.4-9.8) 2.6 (0-3.9) 0.3 (0--1.0) ~ >l "' b::i Totals 118.0 157.1 5.9 22.9 19.1 13.7 10.0 0.0 2.1 0.7 3.8 46.3 9.1 60.6 C1> >l '"' .... Seasonal Plankton Productivity in the Sur/zone of a South Texas Beach the gulf shelf off the beach, but are close to average values for a variety of Texas bays (Odum and Hoskins, 1958). Seasonal measurements of primary and gross production of plankton by the light-dark bottle method for the Gulf of Mexico and South Atlantic areas are limited mainly to the work of Odum and Hoskins (1958) for Texas bays and, of Ragotzkie (1959) for estu­aries in Georgia. The gross photosynthesis and respiration curves for the Upper Laguna Madre and Baffin Bay, Texas, show higher values during summer, hut seasonal changes were virtually absent in Redfish Bay, Texas (Odum and Hoskins, 1958). Ragotzkie's re­sults, which represent more samples, show definite increases of plankton respiration in both spring and summer, whereas net photosynthesis tended to be negative in summer. The low yields of net plankton obtained during the summer months, as compared to the spring and fall, indicate that nannoplankton may be responsible for the greater bulk of summer respiration. The high net photosynthesis of late summer and fall suggest that phytoplankton constitute a major source of organic matter for higher trophic levels. However, until studies that correlate phytoplankton counts with primary· production are undertaken this suggestion must remain speculative. The results of Rodhe et al. (1958) for primary production in Swedish lakes indicate, however, a dominance of nannoplank­ton in total production. The present results indicate that a net production of organic mat­ter does occur in the plankton during the summer. Therefore, the potential exists that net production may be capable of sustaining the beach populations throughout the summer. However, the high respiration of plankton in spring and summer suggests that organic matter is probably imported to the beach in considerable quantities. The importation rates for plankton were not measured, but judging from the strong longshore currents a tremendous bulk of plankton must traverse the beach each day. As a result the higher trophic levels of the beach community probably utilize only a small fraction of the available plankton. Summary (1) Seasonal changes in temperature and salinity along a 10-mile stretch of open Gulf of Mexico beach on Mustang Island, Texas, are reported for October 1959 through Oc­tober 1960. Results reveal a gradual change in temperature from low values of 12-13°C in mid-winter to high values of 33-34°C during summer. Salinity follows the same seasonal pattern, but is more variable, particularly during spring months. (2) Measurements of plankton respiration in dark bottles indicate that highest rates occur during spring when crab and shrimp larvae are abundant. The average summer respiration value of 1.05 g 0Jm3/day exceeds the average winter value by a factor of four. Ne~ photsynthesis is variable throughout the year, but reaches its peak during summer and fall. Net photosynthesis equaled respiration in both summer and winter. With the exception of spring respiration bursts, usually a positive net production oc­curred in the plankton communities swept over the beach. (3) The seasonal maximal plankton metabolism coincides with the abundance of higher trophic levels of the beach environment, and this relation indicates that the im­portation of plankton as a result of seasonal factors is synchronized with the seasonal energy requirements of the beach communities. Seasonal Plankton Productivity in the Sur/zone of a South Texas Beach Acknowledgments This work was financed by an interagency contract for studies of fish stocks and pro­ductivities between the Texas Game and Fish Commission and the Institute of Marine Science, University of Texas, at Port Aransas, Texas. Much of the credit for the work must be given to Messrs. Emilio Guerra, Byung Don Lee and Gonzalo Garza, who participated throughout the period of the study. Literature Cited Faber, H. A., W. D. Hatfield, and M. H. McGrady, Editors. 1955. Standard methods for the exami­nation of water, sewage and industrial wastes. 10th Ed. American Public Health Association, New York. 522 p. Fitch, J.E. 1950. The Pismo clam. Calif. Fish Game 36(3): 28f>..-312. Gaarder, T., and H. H. Gran. 1927. Investigations of the reduction of plankton in the Oslo Fjord. Rapp. et Roc.-Verb. Cons. int. Explor. Mer. 42: 1--48. Gunter, G. 1945. Studies on marine fishes of Texas. Pub. Inst. Mar. Sci. Univ. Tex. 1(1): 1-190. Gunter, G. 1958. Population studies of the shallow water fishes of an outer beach in south Texas. Pub. Inst. Mar. Sci. Univ. Tex. 5: 186-193. Hedgpeth, J. W. 1953. An introduction to the zoogeography of the northwestern Gulf of Mexico with reference to the invertebrate fauna. Pub. Inst. Mar. Sci. Univ. Tex. 3 ( 1) : 107-224. Hedgpeth, J. W. 1957. Sandy Beaches, Chap. 19. In: Treatise on Marine Ecology and Paleoecology, Vol. 1. Ed. J. W. Hedgpeth. Geo!. Soc. Amer., Mem. 67, 1296 p. Koepcke, H. W. and M. Koepcke. 1952. Sohre el proceso de transformacion de la materia organica en las playas arenosas de! Peru. Cienc. Univ. Nae. San Marcos 54(479-480) : 5-29. Loesch, H. 1957. Studies on the ecology of two species of Donax on Mustang Island, Texas. Pub. Inst. Mar. Sci. Univ. Tex. 4(2): 201-227. McFarland, W. N. 1963. Seasonal change in the number and the biomass of fishes from the surf at Mustang Island, Texas. Pub. Inst. Mar. Sci. Univ. Tex. 9: 91-112. Odum, H. T., and C. M. Hoskins. 1958. Comparative studies on the metabolism of marine waters. Pub. Inst. Mar. Sci. Univ. Tex. 5: 16-46. Pearse, A. S., H. J. Humm, and G. W. Wharton. 1942. Ecology of sand beaches at Beaufort, North Carolina. Ecol. Monogr. 12: 135-140. Ragotzkie, R. A. 1959. Plankton productivity in estuarine waters of Georgia. Pub. Inst. Mar. Sci. Univ. Tex. 6: 146-158. Rodhe, W., R. A. Vollenweider, and A. Nauwercke. 1958. The primary production and stand!ng crop of phytoplankton, p. 299-322. In : Perspectives in Marine Biology, Ed. A. A. Buzzati­Traverso, Pt. IL Ryther, J. H. 1956. The measurement of primary production. Limnol. Oceanogr. 1: 72-84. Ryther, J. H., and R. F. Vaccaro. 1954. A comparison of the oxygen and CH methods of measuring marine photosynthesis. J. Cons. int. Explor. Mer. 20 : 25-37. Shepard, F. P. 1950. Longshore-bars and longshore-troughs. Tech. Memor. U. S. Army Eros. Bd. 15, 32 p. Steeman-Nielson, E. 1952. The use of radioactive carbon (CH) for measuring organic production in the sea. J. Cons. int. Explor. Mer. 18: 117-140. Vaccaro, R. F., and J. H. Ryther. 1954. The bacteriocidal effects of sunlight in relation to "light" and "dark" bottle photosynthesis experiments. J. Cons. int. Explor. Mer. 20: 18-24. Seasonal Change in the Number and the Biomass of Fishes from the Surf at Mustang Island, Texas1 W1LUAM N. McFARLAND2 Institute of Marine Science, The University of Texas Port Aransas, Texas Abstract During 1960 and 1961 the numbers and biomass of fishes in the surf at Mustang Island, Texas were measured seasonally by seining procedures. A total of 47 species of fish were captured and are classed as all-year, spring-summer, summer, and winter-spring residents, or, as sporadic occurrences. During winter, on the average only four species were captured from the surf. Species captured increased to an average of 16 during summer. Biomass of fishes increased from a winter mean of 25.8 pounds to a summer mean of 103.2 pounds of fish per surface acre of surf. Mugil cephalu.s was the most common fish and constituted 46% of the total weight of fish captured. The available data on seasonal abundance suggests that the most abundant species, or their ecologic counterparts, are represented heavily in the beach fish fauna from year to year. The most abundant species either are or tend to be predominantly plankton feeders. Estimation of the assimilation and importation of organic carbon to the beach, in the form of plankton, indicate that it is more than sufficient to sustain the fish population during summer. It is concluded that the beach fauna of the Texas coast is largely dependent on plankton for its existence. Introduction The paucity of information concerning vertebrates characteristically associated with outer coastal beach environments has been pointed out by Gunter (1958) . Fishes from beaches in the vicinity of Beaufort, North Carolina were reported by Pearse, Humm and Wharton (1942) while the vertebrates on the outer beach at Mustang Island, Texas, have been reported by Gunter (1945 and 1958). These studies indicate the seasonal fluctuations in the fish faunas of sub-temperate beach environments, wherein the popula­tions decline both in total numbers of fish and in species composition during winter. The results reveal that from 60 to 80 per cent of the fish fauna of the south Atlantic and Texas beaches is composed of but a few species. Seasonal sampling of fishes from an open coast beach near Saint Petersburg, Florida indicate that close similarities in species composition and relative abundance exist with the fish fauna of the Texas coast (Springer and Woodburn, 1960). Dissimilarities appear mainly in the replacement of temperate species with tropical relatives. No data appear to be available on the biomass of fishes characteristic of these beaches. In this paper the species composition, numbers of individuals and the biomass of fishes are reported for the period May 1960 through July 1961. The environment sampled, at Mustang Island, Texas, is the same outer coast beach studied by Gunter (1945 and 1 Contribution No. 58 from the Marine Laboratory, Texas Game and Fish Commission, Rockport, Texas. 2 Present address: Department of Zoology, Cornell University, Ithaca, New York. Seasonal Change of Fishes from the Surf at Mustang Island, Texas 1958) . The information that has accrued on this stretch of coastline, therefore, makes it one of the better known beaches of North America. Materials and Methods EQUIPMENT Estimation of the biomass of fishes from May 1960 through July 1961 was obtained by rapidly setting a large beach seine over a specified area of the surf fringe. The net measured 633 feet in length and was designed to lay into the beach profile. The beach profile in the area of the study maintains a relative constancy throughout the year (Hedgpeth, 1957; McFarland, 1963). As a result the wings of the net were tapered from two feet deep at the ends to ten feet deep where the wings joined the cross piece (relaxed webbing masurements). Webbing was number 9 Nyak twine woven to % inch stretch size ( % inch bar). Plastic three-inch floats were placed one foot apart along the float line. Because of the strong wave action often encountered, heavy floating was required. The lead line consisted of 633 feet of galvanized link chain weighing one-half pound to the foot. Examination of lead line action by diving indicated that the bottom of the net remained on the sand bottom both on the longshore bars and in the troughs. Escape­ment of fish beneath the lead line, if it occurred, probably took place only when the lead line was pulled over small holes. Specific dimensions of the net were: wings, each 200 feet long; cross piece, 185 feet long; bag, 48 feet wide, throat size, 25 feet wide by 8 feet deep, depth of sock 25 feet. The bag was placed in a corner between the cross piece and one of the wings. Because of the longshore currents the bag was set downstream so that it would open into the net. After initial test hauls the depth of the sock was reduced to ten feet to lessen downstream drag on the net. The net was >:et from an 18 foot surf skiff in which the net was stacked flat in a well located midships. The net was payed over the helmsman's head via a rack located above the transom. Early attempts to lay the net from a roped condition led to twisting. Addi­tion of the overhead rack eliminated net twisting and further avoided entaglement of the net with the outboard motor. The entire rig was capable of being propelled in one foot of water, the draft being about 6 to 7 inches loaded and only 3 to 4 inches empty. METHOD OF SETTING THE NET Theoretically an ideal set of the net would cover a rectangular area with the long dimension perpendicular to the surf fringe ( 224 feet) and the short dimension parallel to the beach ( 185 feet) . .The cross piece, thus, usually lay in water of the second long­shore trough at a depth of 6 to 8 feet. The surface area of water enclosed under ideal conditions represented 0.951 surface acre and about 4,550 cubic meters volume. Because of strong longshore currents this ideal was seldom achieved. More often the outward course of the skiff was at a slight angle in the direction of the longshore current. In addi­tion, a degree of net drift occurred before the entire net was payed out. As a result the acreage of water surface covered most often exceeded 0.951 acre. To account for this deviation, at each sampling, a distance of 185 feet was marked out along the beach. The corners of the wings and cross piece of the net were marked with white floats and changes in course were always made at these positions. An individual, Seasonal Change of Fishes from the Surf at Mustang Island, Texas onshore, paced off course changes from the marker posts and transcribed these to a board marked with the ideal course. As a result, with the known dimensions of the net and the measured deviation from the theoretical course the actual area enclosed could be calculated. For the 25 samplings reported in this paper the average area covered was 1.10 acres. A set from start to enclosure of the area, normally took less than two minutes. Once set, the net was hauled immediately upon the beach by pulling first on the upstream wing and crosspiece. A slight pull was maintained on the downstream wing to keep the bag opened into the current. The net was pulled with seine lines snapped to the lead line and attached to two trucks. Inward surf action and the longshore current assisted in relieving tension on the net. The net was beached within ten minutes or less in all samplings. ESCAPEMENT The effectiveness of the chain in reducing escapement of fishes beneath the lead line has been indicated. On several occasions when setting the net the closing wing was terminated 50 to 60 feet out from the beach and provided a route of escape for fishes. However, the presence of a seine line, the fact that the water in this location was only about one foot deep, and the rapid closure of the area from hauling of the net are be­lieved to have cut off escapement. At no time were fishes observed to use this escape route. Escapement over the float line occurred with two species of fish, i.e., Mugil cephalus and Trachinotus carolinus. This occurred on three occasions and seems unusually low since both species a:re predilected toward jumping. Losses were accounted for by record­ing the number of fish that jumped the net. The number that escaped were added to the actual catch and their weight estimated by sampling members of the species actually caught. Escapement through the mesh of the net occurred with very small fishes. Specific losses depended upon the species and their respective abilities to swim through the % inch bar mesh. On several occasions a small fine mesh net was used to surround the bag of the larger net prior to its being hauled from the surf. Fishes which escaped from the larger net under these conditions seldom exceeded 40 mm and more often were under 30 mm in standard length. As a result, all data in this report ignore fish populations in the surf under 40 mm in standard length. This is regrettable, but the extreme size of the net precluded the use of a finer mesh size because the increased drag resistance and the strong longshore currents would have made the net unmanageable. In addition, a smaller mesh size would have seriously reduced the strength of the net. All fish collected were identified to species with the exception of the genus Anchoa and the filefish taken on one occasion. Specimens were weighed individually, but where the number of specimens of a species were large, series of sub-samples containing 20 individuals were weighed at random and the total numbers and weight calculated. The actual catch and the estimated area covered during each sampling were corrected to a one-acre basis. All values reported, thus, represent numbers or pounds of fish per acre. Types and Numbers of Fishes Caught A total of 47 species of fish were caught during the sampling year. The species caught Seasonal Change of Fishes from the Surf at Mustang Island, Texas and the numbers of each species per acre for each sampling are compiled in Table 1. During the winter months the total number of species represented in the collections ranged from a low of two to a high of eight and averaged four. During the rest of the year the number of species ranged from 11 to 21 and averaged 16. On a few occasions considerable numbers of one species were seined. The most ex­ceptional example was the capture on March 1, 1961, of 35,881 specimens per acre of the marine catfish, Galeichthys felis. Throughout the rest of the year this species was represented in individual catches by less than 104 specimens per acre. The high numbers are believed to reflect a breeding movement or aggregation of the populations shore­ward. That this movement was general was demonstrated by the capture of large num­bers of this ~pecies with a smaller net during the afternoon and evening of March 1, 1961. Similarly, large numbers of the striped mullet, Mugil cephalus were taken on December 15, 1960. This is not unusual at this time of year since the species is known to migrate from the Texas bays in large schools during the fall. Another example of un­usually large numbers of a species was encountered on May 26, 1961, when the haemulid, Conodon nobilis, was taken in the surf. At no time in the author's experience had this species been taken from the beach, although it is common in trawl hauls from deeper water off of the beach. Gunter (1945 and 1958) does not report C. nobilis from the surf. Examination revealed that the gonads of many specimens were ripe, but whether the presence of Conodon on the beach represents a breeding movement remains conjecture. The av"erage total number of fish captured per acre during winter was 82 and ranged from 16 to 151 specimens, whereas during spring and summer the average increased to 1,143 fish per acre and ranged from 290 to 2,830. In establishing these estimates, the unusual abundance of catfish on March 1, 1961, has been ignored. Biomass of Fishes For each species, the weight per acre for each sampling and the total weight of fishes per acre are given in Table 2. Total biomass of fishes during the various seasons is shown in Fig. 1. An increase in biomass from the winter lows to the spring-summer highs is evident, although considerable variation occurs from sample to sample. Average total biomass for the winter months, when the species composition of the catch was lowest, was 25.8 pounds per acre (the catches of December 15, 1960 and of March 1, 1961, when high numbers of mullet and catfish were taken have been ignored), and ranged from a low of 5.3 pounds to a high of 48 pounds per acre. During the spring-summer samplings the total catch ranged from a low of 32.5 pounds to a high of 271.8 pounds per acre with a mean of 103.2 pounds. Thus, weight of fish per acre increases fourfold from winter to summer. The number of species represented also increased fourfold for the same periods. However, the average increase in the total number of fishes for this period was fourteenfold and reflects the recruitment of smaller fish, as well as smaller species, into the beach populations during the spring-summer period. Seasonal Characteristics of Fish Populations The primary characteristic of the fish populations is the seasonal change in abundance. An identical result stems from the work of Gunter ( 1958) for the same beach environ­ Seasonal Change of Fishes from the Surf at Mustang Island, Texas 20,000 10,000 5,000 w er 1,000 l) j Dasyatis sabina 3 15 39 90 1 14 18 13 41 20 ~· ;:>-- Rhinoptera bonasus 8 8 ~ Elops saurus 4 4 8 5 3 6 7 1 "' - ;s Harengula pensacolae 1 7 284 133 1 4 3 11 6 74 ;:i Brevoortia patronus 2 19 1 2 9 ... ;:>-- Anchoa sp. 3 8 9 148 32 167 9 16 ~ Galeichthys felis 7 19 19 24 60 38 10 9 104 a* 27 2 2 2 15 5 23 Vi !::! Strongylura marina ..::?.. Syngnathus sp. ~ 6 1 1 1 2 ... 'Mugil cephalus 20 93 13 75 17 4 345 480 7 15 45 72 4 8 9 3 32 60 99 7 605 25 16 10 19 ~ Menidia beryllina 1919 132 99 205 5 ~ Polydactylus octonemus 277 1061 2503 2197 S" 47 83 55 85 330 1118 275 143 1923 38 ;:, Centro porn us ()q undecimalis 1 1 ~ ..... Pomatomus saltatrix 4 11 6 9 6 2 § Elagatis bipinnulatus 3 _r;.. Trachinotus carolinus 124 55 40 34 23 62 4 14 68 2 13 5 57 42 '"-3 Caranx bartholomaei 49 5 1 ~ ~ Caranx hippos 38 47 3 2 12 1 1 20 8 47 "' Chloroscombrus chrysurus 8 .3 l 31 220 780 20 5 Selene vomer 2 2 1 1 2 a• 35,881 catfish. TABLE 1-Continued Date o( Collection Species May 25 July 12 July 19 July 29 Aug. 10 Aug. 18 Aug. 26 Dec. 15 Jan . 13 Jan . 18 Jan. 31 Feb. 9 Feb. 17 Mnr. I Mar. 10 Mar. 20 Mar. 24 Mar. 29 Apr. II Apr. 18 Apr. 28 May 26 May 31 June July 22 7 en <1> ~ "' c Eucinostomus argenteus ;:I !:. Conodon nobilis Bairdiella chrysura Sciaenops ocellata Leiostomus xanthurus 75 10 26 1 42 27 1 57 8 8 42 16 13 26 12 22 2 429 10 15 ("") § O'l <1> 0- Micropogon undulatus 2 7 3 ~ Menticirrhus americanus 23 5 "' Menticirrhus atlanticus Menticirrhus littoralis Pogonias cromis 36 136 154 247 54 401 4 8 3 11 53 16 4 31 4 10 25 1 77 1 40 2 25 3 200 111 3 77 4 ~ "'-... 0 ~ Cynoscion nebulosus Lagodon rhomboides Archosargus probatocephalus 2 3 1 39 3 2 5 2 2 5 3 3 6 2 2 2 2 3 26 10 17 1 59 1 4 1 9 7 2 13 7 1 91 25 2 6 1 28 3 s. <1> en;:: -.:::!.. Chaetodipterus faber 2 5 1 11 13 4 19 ~ ..... Trichiurus lepturus Scomberomerus maculatus 2 1 2 10 ~ ;:: "' ..... ~ Peprilus paru 168 ;:I O'l Paralichthys lethostigma Filefish 11 6 2 5 2 3 ;;;-<...... ~ ;:I _r;,... Lactophrys tricornis Sphaeroides nephelus 25 3 2 2 1 "-3 <1> ~ Opsanus beta 8 ~ "' Histrio histrio ]] ·-­ -·-· ------·­ Totals 568 1335 2754 2564 444 290 1126 547 16 44 7l 151 122 :!5913 87 2172 579 617 538 662 1001 1020 2830 508 419 \0 TABLE 2 Total weight in pounds per acre of each species and of all species at various dates through the years of 1960 and 1961 Date of Collection May July July July Aug. Aug. Aug. Dec. Jan. Jan. Jan. Feb. Feb. Mar. Mar. Mar. Mar. Mar. Apr. Apr. Apr. May May June July Species 25 12 19 29 10 18 26 15 13 18 31 9 17 1 10 20 24 29 11 18 28 2G 31 22 7 Scoliodon terranovae 1.2 18.0 Sphy rna tiburo 6.5 Narcine braziliensis .G 0.8 1.3 .4 Dasyatis americana Dasyatis sabina Rhinoptera bonasus Elops saurus H arengula pensacolae Brevoortia patronus Anchoa sp. Galeichthys felis Strongylura mari11a Syngnathus sp . Mugil cephalus Menidia beryllina Polydactylus octonemus Centropomus undecimalis Pornatomus sdltatrii­ .3 2. 1 .1 .9 14.9 1.2 1.9 .2 .3 2.0 1.1 .2 26.4 37.7 1.4 1.4 G.G .I .I .2 4.2 198.2 59.4 28.0 1.9 .5 1.2 5.8 2.1 12.0 22.7 4.7 .2 1.3 .2 2.0 2.4 5.8 1G.1 16.7 2.6 4.9 4.6 17 .ti .1 92.5 373.1 3.9 .2 3.2 .3 8.3 21.3 2.6 .1 .1 32.2 20.G 2.0 1.7 u' 8.3 .2 3.0 7.0 .1 .1 .1 12.6 33. 1 3.0 2.7 .3 <.1 10.4 .4 .3 2.3 ·:5 1.3 2.3 6.0 <.1 1.0 .2 39.2 1.7 .7 5.3 5.0 <.l .1 .1 .1 .2 2.5 164.6 2.5 2. 7 4.1 17 .8 1.0 .6 5.3 2.3 -~ 2.3 7.8 3.1 1.5 1.li 1.2 7.8 2 1.9 1.2 20.0 .G .1 .2 .4 .1 .4 9.4 .9 7 .5 1.7 Elagatis bipinnulatus Traclzinotus carolinus 1.6 4.1 2.9 2.9 .1 2.7 8.1 8.4 28.2 31.6 .1 1.4 3.2 .9 6.7 2.1 Caranx bartholomaei .1 3.3 .4 .2 Caranx hippos Chloroscombrus chrysurus Selene vomer 1.0 .1 2.2 .7 .2 .4 .2 .1 1.7 .1 <.1 .! .2 .2 .1 7.3 .t 8.6 31.3 3.4 3.1 .5 .2 Eucinostomus argenteus Conodon nobilis 117.9 <.I 1.9 Bairdiella chrysura Sciaenops ocellata Leiostomus xantlzurus 16.6 2.1 2.8 6.6 2.2 9.9 7.2 2.4 14.1 1.9 1.6 11.3 .4 1.G 4.8 .1 3.8 .5 3 () 1.0 2.5 M icropogon undulatus M enticirrhus americanus .5 2.1 1.7 2.7 .8 1.4 Menticirrhus atlanticus .9 .9 .9 J\tlenticirrhus littoralis 6.2 25.8 24.6 8.6 10.2 25.3 .4 3.4 3.4 5.1 .7 7.3 12.3 8.0 1.6 2.6 4.7 Pogonias cromis Cynoscion nebulosus Lagodon. rhomboides Arclwsargus probatocephalus ChaeLodipterus faber 1.2 .G .3 4.0 .2 1.6 .2 .6 2.4 4.3 .6 3.5 .3 5.7 9.0 .ti 3.9 7.6 .2 2.4 .'.l 2.8 .1 .1 .7 .5 18 .5 .5 2.3 39.2 .8 4.3 12.6 <.l 2.2 6.1 1.1 2.4 1.0 2.4 <.1 .5 1.6 2.3 1.0 11 .6 2.7 13. l 3.6 1.4 .3 9.1 1.2 1.4 3.1 5.0 1.0 .3 9.0 2.8 .5 3.8 3 •> 3. 1 Trichiurus lepturus Scomberomorus maculatus .8 .2 1.1 < .1 .l .! .H Peprilus paru Paralichthys lethostigma 1.8 .2 1.4 3.8 .2 4.6 .t .1 .1 Filefish La.ctophrys tricornis Sphaeroides nephelus Opsanus beta liistrio histrio 2.1 .3 .2 .3 2.3 .1 < .l Totals 48.0 86.9 102.3 271.8 45.0 84.9 213.6 395.7 5.3 11.0 22.0 48.0 24.7 10,689.6 44.2 135.5 35.6 32.5 46.8 37.9 238.1 172.7 80.6 79.0 43.9 a•-10,651 .7 lbs/ncre. TABLE 3 Seasonal occurrence of resident fishes in the surf at Mustang Island, Texas. Resident fishes are defined as forms which occur on several occasions during a season. Bracketed num­ bers refer to the abundance rank of a species on the basis of total weight captured during the year. All year residenls Spring-summer residents Summer residents Winter-spring residents Galeichthys /eli,s (9) Dasyatis sabina (7) M ugil cephalus (1) H arengula pensacolae Lagodon rhomboides Anchoasp. M enidia beryllina (13) Polydactylus octonemus (2) Pomatomus saltatrix Trachinotus carolinus (5) Caranx bartholomaei Menticirrhus americanus Menticirrhus atlanticus M enticirrhus littoralis (3) Pogonias cromis (6) Cynoscion nebulosus (12) Archosargus probatocephalus (10) Chaetodipterus Jaber (20) Paralichthys lethostigma Rhinoptera bonasus (14) Elops saurus (16) Bairdiella chrysura Brevoortia patronus Caranx hippos (19) Chloroscombrus chrysurus (11) Leiostomus xanthurus (8) Micropogon undulatus Scomberomorus maculatus Peprilus paru Seasonal Change of Fishes from the Surf at Mustang Island, Texas spawning history of this species is fairly well documented for the Texas coast and the seasonal changes encountered in this study agree with spawning and growth habits of pompano (see Gunter, 1958; Springer and Pirson, 1958) . On a basis of weight of fishes per acre, nine of the sixteen species which can be classed as spring-summer residents were amongst the 20 most abundant species for the collecting year. SUMMER RESIDENTS Nine species can be classed as summer residents (Table 3). Of the nine, five are amongst the 20 most abundant fishes. Caranx hippos, Chloroscombrus chrysurus, Micro­pogon undulatus, Scomberomorus maculatus and Peprilus paru enter the beach popula­tions as summer progresses. WINTER-SPRING RESIDENTS One species, Bairdiella chrysura, was captured only during the winter and spring periods. I ts absence from the beach during summer is unexpected, since it is common in the bays and from deeper water of the gulf shelf. SPORADICS Of the total number of 47 species captured, 18 occurred in the catches in a sporadic manner (Table 4). Most of the sporadic occurrences were encountered during the sum­mer months. All of the elasmobranchs and the redfish, Sciaenops ocellata, are common just outside the surf zone. Although the redfish was represented only sporadically in the collections, this species is taken commonly in the surf by anglers. Night seining with smaller nets yielded increased numbers of redfish, but why the catch was low during daylight seine hauls is uriknown. The results suggest that redfish may move into the shallow surf water primarily at night, or, that redfish are adept at escaping a seine during daylight hours. The latter possibility appears most likely since Gunter has found both redfish and black drum to be wary of boats even when drifting (personal communi­cation). TABLE 4 Sporadic occurrence of fishes in the surf at Mustang Island, Texas. Numbers refer to the rank of the individual species on the basis of total weight captured during the year. Sporadic fishes are defined as species that occur on but few occasions during a season. Spring-summer Winter and winter­sporadics Summer sporadics spring sporadics Syngnathus sp. Scoliodon terranovae (18) Sphaeroides nephelus Sphyrna tiburo Opsanus beta N arcine braziliensis Dasyatis americana Strongylura marina Centropomus undecimalis (17) Elagatis bipinnulatus Selene vomer Eucinostomus argenteus Conodon nobilis (4) Sciaenops ocellata Trichiurus lepturus Filefish Lactophrys tricornis His trio his trio Seasonal Change of Fishes from the Surf at Mustang Island, Texas Relative Abundance of the Various Species of Fishes In his study of the fishes of the Mustang ldand surf, Gunter ( 1958) indicated the relative "dominance" of several species on the basis of the numbers of each species cap­tured. Similar measures of relative abundance can be established from the present data. However, neither numbers of fishes nor relative biomass are a complete index to the dominance of a given species in an environment. Of the two measures biomass contains more ecological information. The absolute and the relative abundance of fishes in the surf zone, therefore, are reported preferably in terms of weight of fish per acre. In ranking the fishes according to yearly abundance, the enormous catch of catfish on March 1, 1961 has been disregarded. Since Galeichthys felis from this one collection constituted almost 65% of the entire weight of all fishes captured and, since its presence in large numbers is believed to be the result of breeding movements, its inclusion would bias conclusions on relative abundance. The exclusion of the data for March 1 is in part justified by the fact that large numbers of G. felis were captured only for this one sampling, although catfish were resident throughout the year but in lesser abundance. The 20 most abundant fishes are presented on the basis of weight and of numbers per acre in Table 5. On the basis of weight, Mugil cephalus is by far the most abundant fish. The next four most abundant species, Polydactylus octonemus, Menticirrhus littoralis, Conodon nobilis and Trachinotus carolinus, when included with M. cephalus, constitute 70% of the catch during the year. Conodon nobilis cannot be considered as a typical resident of the surf, since it is usually absent from beach seine hauls. If its brief, spectacular appearance is excluded, the other four species still constitute the major proportion of all fishes taken from the surf ( 63.4%). When the percentage representation in all catches is expressed on a number of indi- TABLE 5 Percentage abundance of fishes which occurred in the surf at Mustang Island, Texas* Standing crop {lbs fish/acre) Numbers o( fish/acre cumu­ cumu· per cent Ialive per cent lative Species of all catches percent Species of all catch~s percent Mugil cephalus Polydactylus octonemus Menticirrhus littoralis 46.07 7.54 6.56 46.07 56.61 60.17 Polydactylus octonemus Menidia beryllina Mugil cephalus 44.53 11.51 10.16 44.53 56.04 66.20 Conodon nobilis 5.24 65.41 M enticirrhus littoralis 7.12 73.32 Trachinotus carolinus 4.58 69.99 Chloroscombrus chrysurus 5.21 78.53 Pogonias cromis Dasyatis sabina Leiostomus xanthurus 3.69 3.38 2.82 73.68 77.06 79.88 Trachinotus carolinus Harengula pensacolae Conodon nobilis 2.65 2.59 2.17 81.18 83.77 85.94 Galeichthys felis Archosargus probatocephaius Chloroscombrus chrysurus Cynoscion nebulosus M enidia beryllina Rhinoptera bonasus Lagodon rhomboides Bairdiella chrysura Elops saurus Centropomus undecimalis Scoliodon terranovae 2.52 2.46 1.91 1.90 1.75 1.72 1.44 1.07 0.91 0.86 0.84 82.40 84.86 86.77 88.67 90.42 92.14 93.58 94.65 95.56 96.42 97.26 Anchoa sp. Galeichthys felis Lagodon rhomboides Leiostomus xanthurus Dasyatis sabina Menticirrhus atlanticus Caranx hippos Bairdiella chrysura Pogonias cromis Chaetodipterus faber Caranx bartholomaei 1.91 1.80 1.63 1.33 1.25 0.99 0.87 0.61 0.39 0.29 0.27 87.85 89.65 91.28 92.61 93.86 94.85 95.72 96.33 96.72 97.01 97.28 Caranx hippos 0.77 98.03 Archosargus probatocephalus 0.19 97.47 •Data are for the 20 most abundant fishes of the 47 species taken, according to the respective system of measu["emeol. Seasonal Change of Fishes from the Surf at Mustang Island, Texas vidual basis (Table 5) the order of abundance of species is slightly changed. However, the three highest ranking species on the basis of weight are still included among the four most numerous species. When both numbers and biomass are considered jointly, tendencies are revealed which correlate with information that has been accumulated on the productivity of the beach environment. First, Mugil cephalus and Polydactylus octonemus are predominantly plankton feeders (M. cephalus is more often considered a grazer, cf. Darnell, 1958). On a weight basis, M. cephalus and P. octonemus constitute 53.61 % of the total yearly catch. If only the catches for June, July and August are considered they still constitute 47.76% of the total biomass. Thus the most abundant surf fishes are plankton feeders. Furthermore, their maximum abundance during spring and summer parallels the maxi· mum abundance of plankton in the surf (McFarland, 1963) . Of the remaining 18 species listed in Table 5, that are ranked on the basis of weight, only Harengula pensacolae, Anchoa sp. and possibly Menidia beryllina can be classed as plankton feeders. When both numbers and weight are considered, Menticirrhus littoralis is less abundant than either M. cephalus or P. octonemus, but distinctly more abundant than all other species (Table 5). Menticirrhus littoralis feeds primarily on bottom in­vertebrates (Darnell, 1958) . The remaining species are bottom feeders also, living off various crustaceans and molluscs or, in a few instances, other fishes. However, many of the fohes have been observed to consume large quantities of zooplankton when it is abundant in the surf. Direct examination of the stomach contents of Mugil cephalus, Trachinotus carolinus, Caranx hippos and Chloroscombrus chrysurus revealed that their stomachs were often full of crustacean larvae. How generalized plankton feeding might be to surf fishes that normally feed on bottom dwelling forms is not known; also, it is not known whether phytoplankton cropping occurs during periods when zooplankton are not abundant in the surf, such as during mid-summer. A comprehensive analysis of the food habits of the fishes in the surf at the various seasons would be valuable in establishing whether the smaller biomass of bottom feeding fishes relative to plankton feeding fishes is related to an inability of the former to utilize plankton, to a lesser availability of the bottom fauna or, to both. Comparison With Previous Work In his 1958 paper, Gunter was able to demonstrate for the year 1947-48 that a seasonal succession occurred in the fish populations on the Gulf beach. Two species, Trachinotus carolinus and Harengula pensacolae were the most numerous and consti­tuted 68% of the catch. Mugil curema, which was the third most abundant species con· stituted about 6% of the catch. Thus three species comprised nearly 75% of the total number of fishes taken throughout the year. The results reported by Gunter are for the most part representative of fishes smaller than 100 mm in total length. In this study net selectivity eliminated fishes smaller than 40 mm standard length. Thus, present data overlap Gunter's findings and extend them to include the larger fishes. The most con­spicuous difference between the studies are the decreased representation of H. pensacolae and the virtual replacement of M. curema by M. cephalus in present collections. For example on July 19, 1960, only one specimen of H. pensacolae is reported in the catch (Table 1), but 734 individuals were taken by the small fine mesh net used to surround the bag prior to beaching the large net. Most certainly, H. pensacolae would constitute a Seasonal Change of Fishes from the Surf at Mustang Island, Texas considerable portion of the standing crop if specimens of less than 40 mm standard length could be included. The replacement of M. curema by M. cephalus is baffling, but ecologically there is probably little difference between the two forms. Gunter (1958) suggests that during any given season the species composition might fluctuate from year to year and gives examples for the years of 1945 and 1947-48. The heavy representation of Trachinotus carolinus, Harengula pensacolae and Polydactylus octonemus that he reports are certainly characteristic of the more abundant species for this study (Table 5), even though H. pensacolae probably constituted a greater bulk of the total population than indicated. Thus, in spite of changes in species composition from year to year, the more abundant species and particularly similar ecologic types are of constant occurrence. It is considered of major importance to the survival of the surf fish stocks that the most abundant species are plankton feeders, or are potentially capable of feeding on plankton. Primary Productivity of Plankton and its Relation to the Biomass of Fishes Results on plankton productivity of the Mustang Island surf zone indicate that net photosynthesis is lowest in winter, sporadic in spring and increases to its highest values in the summer-fall period (McFarland, 1963). Plankton respiration is lowest in winter, but peaks during spring and then levels off at a summer rate four times the winter rate. The increased plankton abundance of the spring-summer-fall period, coincides with the increase in the biomass of fishes. A major question that can be posed, therefore, is whether the abundance of plankton in the surf is sufficient to serve as the primary food source for the fish populations. A final answer is at present not available. However, rough estimates of fish metabolism and carbon requirements suggest that the abundance of plankton is sufficient to supply the energy needs of the fish populations. If the average summer oxygen consumption of the beach fishes is assumed to be 0.5 ml/gram wet weight per hour, then the total consumption of oxygen by beach fishes would be 777 grams/ surface acre per day (based on the mean biomass of 100 lbs. fish per acre). If the R.Q. of all surf fishes averaged 0.80, then 860 grams of carbon dioxide or 232 grams of carbon (860 X 0.27) would be produced metabolically per acre per day. Growth of fishes per day, as based on Hellier's ( 1962) data for fishes in the Laguna Madre, Texas, would not exceed 10 grams of carbon/acre of surf per day if the carbon assimilation were 1007c efficient. Correcting for a food conversion by the fishes of only' 10% (Brown, 1957) yields a total daily organic carbon requirement of from 300 to 350 grams/acre. The only known primary producing source capable of sup· plying this daily carbon requirement which occurs in the beach environment is the surf plankton. The mean summer net photosynthesis of plankton in the surf at Mustang Island was 1 gram 0 2/ m3 per day. Converting the oxygen production to assimilated carbon by use of a factor of 1.25 (Ryther, 1956) yields a production of 5,688 grams organic C/ acre per day. The carbon assimilation, therefore, is from 15 to 18 times in excess of the daily carbon requirement of the fishes. The carbon requirement of the infauna was not· measured, but it seems unlikely that it would exceed the requirement of the fishes. Indeed, 104 Seasonal Change of Fishes from the Surf at Mustang Island, Texas judging from the data of Loesch (1957) on the biomass of Donax in the Mustang Island beach the total infauna probably represents less than 5 and certainly less than 10% of the fish biomass. Thus, even if the beach was a closed system, the summer plankton production would be more than sufficient to supply the food requirements of the fish populations. However, the beach environment is an open system and the water mass and its contained plankton are constantly imported to the beach during summer from the open Gulf of Mexico. Neither organic importation nor the biomass of plankton in the water have been measured, but judging from the high plankton respiration and the strong longshore current systems that traverse the beach (McFarland, 1963) it seems probable that the daily import and ex­port of plankton to and from the beach are several orders of magnitude in excess of the energy requirements of the beach fauna. For instance, a longshore current of one knot would exchange the water mass over a given area of beach nearly 700 times per day. Yet longshore currents normally exceed one knot and, therefore, water exchange often would exceed a daily turnover of 700. Under these conditions, if the plankton biomass was moderate and the biomass of surf fishes during summer was relatively stable as the data indicate, then the importation of plankton to the beach in currents would be sufficient to meet the energy requirements of the beach populations. The intricacies of the energy exchange between the beach populations remains to be balanced. However, the trophic dependence of the beach fauna of the Texas coast on plankton, at least during summer, seems certain. This conclusion is supported by the evidence for a large net productivity of plankton, the probable high importation and ex­portation of plankton to and from the beach and, the demonstration that the most abun­dant fishes in the surf are either plankton feeders or are capable of plankton feeding. In further support of this contention is the fact that the most abundant mollusc of the in­fauna, Donax variabilis, is also a plankton feeding organism. Summary ( 1) The seasonal abundance of fishes with respect to numbers and biomass for the surf zone at Mustang Island, Texas, are reported for the year 1960-61. Results reveal that both species composition and total abundance are lowest in winter and increase during the spring-summer periods. (2) During winter an average of four species of fishes were taken by seining, whereas the summer average was 16 species. A total of 47 species were captured during the col­lecting year and are classified as all year, spring-summer, summer, and winter-spring residents, or, as sporadic occurrences. (3) The average standing crop of fishes during winter was 25.8 pounds of fish per surface acre of surf (ca. 4,550 m3 water) and increased to an average of 103.2 pounds during the summer. ( 4) The striped mullet, Mugil cephalus constituted 46% of the total catch on a weight basis and was by far the most abundant species. The next five most abundant fishes were Polydactylus octonemus, Menticirrhus littoralis, Conodon nobilis, Trachinotus carolinus and Pogonias cromis. Together they constituted 27.61 %of the total ca!ch. (5) The relative abundance of the fishes are compared with previous studies; it is con­cluded that a similar species composition is maintained from year to year, although a Seasonal Change of Fishes from the Surf at Mustang Island, Texas particular species may vary in rank or be replaced by a close relative or ecologic counterpart. (6) The theoretical carbon requirement of fishes is calculated and related to the availability of carbon in the plankton. It is concluded that the recruitment of plankton from net productivity and from importation is at least several orders of magnitude in excess of the food requirements of the fishes. Acknowledgments Innumerable individuals assisted in the seining procedures during the course of this study. Their constant willingness to help is gratefully acknowledged and it is hoped that the participants will forgive the necessary omission of their names. One individual, Mr. Emilio Guerra, maintained the equipment, measured and counted fish and performed often near impossible tasks throughout the period of the study. Much of the data must be accredited to his perseverance. The work was financed by an interagency contract be­tween the Texas Game and Fish Commision and the Institute of Marine Science, University of Texas, Port Aransas, for studies of fish stocks and productivities. Literature Cited Brown, M. E. 1957. Experimental studies on growth, Ch. 9, p. 361--400. In M. E. Brown, (ed.), The physiology of fishes, Academic Press, New York. Darnell, R. M. 1958. Food habits of fishes and larger invertebrates of Lake Pontchartrain, Louisiana, an estuarine community. Puhl. Inst. Mar. Sci. Univ. Tex. 5: 353-416. Gunter, G. 1945. Studies on marine fishes of Texas. Puhl. Inst. Mar. Sci. Univ. Tex. 1(1), 190 p. Gunter, G. 1958. Population studies of the shallow water fishes of an outer beach in south Texas. Puhl. Inst. Mar. Sci. Univ. Tex. 5: 186-193. Hedgpeth, J. W. 1957. Sandy beaches, Ch. 19. /n J. W. Hedgpeth, (ed.), Treatise on marine ecology and paleoecology, Vol. 1. Geo!. Soc. Amer. Mem. 67, 1296 p. Hellier, T. R. 1962. Fish production and biomass studies in relationship to photosynthesis in the Laguna Madre of Texas. Puhl. Inst. Mar. Sci. Univ. Tex. 8: 1-22. Loesch, H. C. 1957. Studies of the ecology of two species of Donax on Mustang Island, Texas. Publ. Inst. Mar. Sci. Univ. Tex. 4(2): 201-227. McFarland, W. N. 1963. Seasonal plankton productivity in the surface of a south Texas beach. Puhl. Inst. Mar. Sci. Univ. Tex. 9: 77-90. Pearse, A. S., H. L. Humm, and G. W. Wharton, 1942. Ecology of sand beaches at Beaufort, North Carolina. Ecol. Monogr. 12: 135-140. Ryther, J. H. 1956. The measurement of primary production. Limnol. Oceanogr. 11: 72-84. Springer, V. G., and L. Pirson. 1958. Fluctuations in the relative abundance of sport fishes as indi­cated by the catch at Port Aransas, Texas, 1952-1956. Puhl. Inst. Mar. Sci. Univ. Tex. 5: 169-185. Springer, V. G., and K. D. Woodburn. 1960. An ecological study of the fishes of the Tampa Bay area. Prof. Pap. Ser. Fla. Bd. Consv. 1: 104. Growth and Decay of Penicillus capitatus Lamarck in the Lower Laguna Madre of Texas1 LAZERN 0. SORENSEN Department of Biology, Pan American College Edinburg, Texas Abstract The entire standing population of Penicillus capitatus Lamarck in the lower portion of the Laguna Madre was destroyed by reduced salinity in the fall of 1958. The area had almost completely recovered from the effects of low salinity by 1960. Studies of the growth and calcium content of Penicillus capitatus in the extreme lower portion of the Laguna Madre were made for May 1961 through February 1962. Characteristics of growth and destruction of this tropical form in its northern range were recorded as well as observations on re­generation of the exposed portions of Penicillus. Mean dry weight of Penicillus during this time was 5.14 grams per core of 4 inch diameter. Mean calcium carbonate weight was 1.99 grams per core of 4 inch diameter. In January 1962, low temperatures destroyed almost the entire Penicillus population in the lower Laguna Madre of Texas. In January, 1963, a remnant portion of the former population remains, scat­tered among an area dominated by the sea grass, Thalassia. Introduction The occurrence of Penicillus capitatus in the extreme southern portion of the lower Laguna Madre is of considerable interest because it is the principal calcium depositing alga which occurs in this area. Humm and Hildebrand ( 1962) reported its occurrence on muddy, sandy flats in three to five feet of water between the causeway bridge and the ship channel at Port Isabel. In some areas, there were several hundred plants per square meter. The muddy, sandy bottom of much of the shallow portion of the lower Laguna Madre has from time to time been heavily populated with Penicillus. In some areas, Penicillus has been the single conspicuous dominant, and in others it has shown scattered occurrence among the rhizomes of the sea grass, Thalassia testudinum Konig and Sims. Little is known about the growth or reproduction of this calcareous depositing algae which occurs in tropical and sub-tropical waters. Woronin, as early as 1861, reported the presence of spherical bodies on Penicillus which he thought might be zoosporangia. A. and E. S. Gepp, in their monographic account of Penicillus in 1911, discussed the earlier reports of reproduction of the genus and stated that no satisfactory information had been published. Fritsch ( 1956) maintains that so-called reproductive organs re­ported for Penicillus have proved to be epiphytic organisms. Elsie Kupper ( 1907) studied regeneration in Penicillus by cutting off the "heads" of a number of these algae and found that after 38 days, a new tuft of loose filaments had 1 Based on observations and measurements from 1958 through 1962 with the aid of NSF Grant l 1867. Penicillus capitatus Lamarck in the Lower Laguna Madre of Texas begun to form. A. and E. S. Gepp ( 1911), in reviewing Miss Kupper's work, stated that the figure in her text also showed that similar filaments had broken out singly or in groups along the stipe. The purpose of this paper is to present data on the vegetative growth of Penicillus capitatus and to discuss the environmental factors which cause drastic fluctuations in its populations in this area and prevent its extension farther north along the Texas Coast. Methods Visual observations of the Penicillus population in the area studied were begun during the spring of 1958. At that time the species contributed significantly to the biomass of the area, but after its destruction in the fall of 1958, it did not reappear in any sizeable · quantity until the summer of 1960. During 1961, a study was begun in an effort to determine the growth rate of Penicillus and the rate of calcium carbonate deposition. An area was chosen for investigation in which the Penicillus growth was luxuriant and other macroscopic forms limited or lacking. Samples of the vegetation were taken each week. Dry weight bases were used to determine the ratio of the total weight and the calcium carbonate content of the Penicillus population. The sampling was done by taking cores of material from Penicillus beds in a relatively shallow bay area which borders the extreme southern tip of Padre Island. Cedar posts were used to mark the location of the beds and the samples were taken by stepping off a random number of spaces from a post in a random direction and then securing a core. Six cylindrical cores four inches in diameter taken from these areas, each covering approximately two acres in which Penicillus was the most abundant form, constituted the sample each time. Each core was washed in a 1/ 16 inch mesh screen box to separate the Penicillus plants from the bottom sediments. The Penicillus plants, consisting of rhizoids, stipe and head, were rewashed, dried at 105° C for 24 hours and weighed. The dried specimens were then treated with a 10% solution of HCl to remove the calcium carbonate, which is deposited in the form of aragonite. The decalcified specimens were then dried at 105 ° C for 24 hours and reweighed. The difference in dry weight of the specimens before and after trea,tment with HCl gives an indication as to the amount of CaCO., present. Salinity and temperature determinations were made at the level of the stipes each time the samples were collected. Salinity measurements were made with the aid of a precision calibrated specific gravity hydrometer and checked by the electrical con­ductivity method. Salinity values were expressed in parts per thousand. Water tempera­tures were recorded with the aid of a 0° to 100° Centigrade thermometer graduated to read in tenths of a degree. Field observations for the most part were made by wading or by use of a face mask which permitted observations of the attached forms when visibility permitted. During 1961, some studies were made by use of a boat and a glass bottomed tub for rapid scanning of an area, followed by the use of the mask for more detailed observations. Penicillus plants were uprooted from the mud bottom and transplanted to the labora­tory. They were placed horizontally in marine water of 30 %oand kept at room tempera· ture in subdued light. Plants were also moved into aquaria and replanted into mud taken from the area in which they were collected, but results obtained from such transplants have not been suitable because of the lack of uniformity in response to transplantation. Penicillus capitatus Lamarck in the Lower Laguna Madre of Texas Results and Discussion During the summer of 1958, the lower Laguna Madre in the vicinity of the Port Isabel-Padre Island causeway exhibited an extensive and luxuriant growth of Penicillus capitatus. The growth occurred in water one to six feet in depth and provided a dense stand of several hundred plants per square meter on much of the mud and sand bottom of the entire area. In areas dominated by sperrnatophytes, Penicillus occurred as single plants or in small groups of two or three interspersed among the grasses. The plants have not been observed north of Port Mansfield in the Laguna Madre of Texas. In the fall of 1958, the Rio Grande Valley watershed area south of Falcon Darn ex­perienced a series of unusually heavy rains resulting in much local flooding. The flood­way system was opened to carry the excessive flood water into the Laguna Madre at a point where the Arroyo Colorado joins the hay. At this time salinity of the lower hay was stationary at 8 %o for several weeks. The entire population of Penicillus disappeared at this time. The only evidence of their past existence was the dead stipes that contained calcium carbonate. During 1959, one small area consisting of patches of Penicillus was discovered be­tween the ship channel and a deep trench that had been dug when the causeway was built. The salinity around this area may not have changed as drastically as that in the much shallower hay. The immediate area surrounding the remnant bed was the first to be re-populated by Penicillus and each successive visual inspection revealed plants further from the place where they were first found. The species continued to re-establish itself over the area it had formerly occupied. In the fall of 1960, it was nearly as abun­dant in the extreme lower hay area as before the influx of fresh water. During the summer of 1961, water temperatures were normal. Generally in the early morning, water transparency was good, hut by mid-morning, the wind disturbed the water and the resultant turbidity was such that only 10 to 15% of the surface light reached the floor of the hay which supported Penicillus growth at a depth of approxi· rnately two feet. Rainfall was nearly normal. During the summer of 1961, Penicillus was found occupying a prominent position in the extreme lower portion of the Laguna Madre reaching northward about five miles from the causeway. It occurred as the conspicuous dominant attached alga located chiefly as small to larger areas among the grassy areas of the bottom. It was the only attached inhabitant in the areas recently disturbed by dredging operations. In areas where the sea grasses were well established, Penicillus, although present, consisted of small scattered groups of isolated plants. Data for the growth of Penicillus and the rate of calcium carbonate deposition are graphically represented in Fig. l. Salinities and temperatures are also shown. During the months of August and September, there was a continuous visible change in the Penicillus population with the disappearance of the older grayish-green stipes and the appearance of the young brilliant green stipes. Death of older plants near the center of the bed occurred, and there was an extension of the bed into adjacent areas by the new stipes. The calcium carbonate content of the new stipes was low, hut as carbonate deposition progressed there was a color change of the stipes to grayish-green. On September 10, 1961, tropical hurricane "Carla" swept into the middle of the Texas coast. In several areas, Padre Island was cut by the Gulf waters and high waves and wind pushed much water into the bay. The water level in the lower hay remained at Penicillus capitatus Lamarck in the Lower Laguna Madre of Texas 19 61 JULY DEC. 1962 15 10 10 5 DRY WEIGHT CALCIUM CARBONATE Ot-~--+~~~~+-~~~-+~~~~+-~~~-+~~~--;,.-~~~-+-~~~-+--t 35 2.0 15 10 5 IRANGE RANGE -STANDARD ERROR OF THE MEAN \\ /,,/"\ /'\ \." \.,. __./ \ / \ ' \ \ \ ice \ t, l r, \ I \ .. _.... / ' .... ... J \I \ I \/ \ I v \ / '.! i -SALINITY %0 ? ---TEMPERATURE °C JUNE JULY AUG. SEPT. OCT. NOV. DEC. JAN. 1961 1962 Frc. 1. Fluctuations in temperature, salinity, and dry weight and calcium carbonate content of populations of Penicillus in the lower Laguna Madre of Texas, June 1961 through January 1962. Weights are in grams per four inch diameter circle. Penicillus capitatus Lamarck in the Lower Laguna Madre of Texas a higher than normal level for nearly a month after the storm had struck. Heavy rains followed the hurricane with an accompanying decrease in salinity to 22.5 %o-This change in salinity had little visible effect on the Penicillus population. On January 9, 1962, a severe cold front moved across the bay area. A thin sheet of ice formed on January 10 and 11, 1962, but with wind from the north, the ice was piled approximately 16 inches deep on the Penicillus area that had been used for study pur­poses. Sediment was also laid down on top of the plants so that only the heads protruded in much of the area. Within one month, the entire Penicillus population throughout the entire lower Laguna Madre died, leaving only fragments of the calcified stipes littering the area. Examination of known areas where Penicillus had occurred before failed to disclose a single live specimen. On January 9, 1962, before the cold front moved in, the weather was balmy, the tide low, visibility excellent. Several Penicillus stipes with heads intact and a portion of the rhizoidal mass attached to the basal ends was moved into the laboratory and kept in a horizontal position in an aquarium containing water with salinity of 30 %0• Within three weeks new growth appeared in the form of multiple stipes from the basal region where the rhizoidal mass was attached to the stipe. Filaments comprising the original head continued to elongate. Along the stipe, individual filaments emerged and formed single Yertical filaments. Fig. 2 shows these plants after the formation of vegetative structures and before they were transplanted to an aquarium which contained a layer of material which had been taken from the bottom of the bay. The stipes continued to pro­duce almost normal appearing plants, with a rhizoid mass generating from the base of each stipe. The heads were more loosely formed than were those of the original plants. The single filaments which had arisen from the side of the stalk persisted for over a month but did not change in appearance. Under microscopic examination, they were found to be identical to those filaments taken from the heads. The mass of rhizoids in the Penicillus bed at the time of the freeze did not appear to FIG. 2. Penicillus plants as taken from the bay and placed horizontally in an aquarium. One or more stipes formed at the basal end of the plant and loose filaments arose from the sides of the plant and at the apex. Penicillus capitatus Lamarck in the Lower Laguna Madre of Texas lll have been destroyed. Some of this material was transplanted to aquaria in the laboratory where single Penicillus filaments emerged. In about two weeks they grew to a length of two inches, persisted for several weeks, and then disappeared. No comparable appearance was observed in the bay, but they might easily have been over-looked because of their diminutive size and the typical poor visibility following the destruction of the major por­tion of the plant and animal life in the lower bay area. They did not produce identifiable stipes in the bay and the rhizoids became much attenuated and gradually less abundant until they were no longer detectable in the mud bottom. In July, 1962, small patches of young Penicillus stipes were discovered in the same vicinity as those which appeared in 1959 following destruction of the population by the reduced saline conditions. They were confined to areas less than one meter in diameter, scattered among a thickly populated area of Thalassia. The plants confined to these open areas were not numerous and none was found scattered among the T halassia. The plants have continued to extend their area at the margin of each small patch of existing Pencillus until the fall of 1962. At this time plants could be found intermingled with the Thalassia, covering an area of approximately twenty acres. Acknowledgment These studies were aided by the National Science Foundation with Grant NSF G 17867 to study the growth of Penicillus capitatus in the lower portion of the Laguna Madre during the period May, 1961 to February, 1962. The suggestions of Dr. John T. Conover of the Naragannsett Marine Laboratory and Dr. Howard T. Odum of the Texas Institute of Marine Science are gratefully acknowledged. Literature Cited Fritsch, F. E. 1956. The Structure and Reproduction of the Algae. Cambridge, England, Cambridge Univ. Press. I: xvii-791. Gepp, A., and E. S. 1911. "The Codiaceae of the Siboga Expedition, including a monograph of Flabellarieae and Udoteae." Siboga-Exped. Monogr. 62. Leiden. Humm, H. J., and H. H. Hildebrand. 1962. Marine algae from the Gulf Coast of Texas and Mexico. Pub!. Inst. Mar. Sci. Univ. Tex. 8: 227-268. Kupper, Elsie. 1907. Studies in Plant Regeneration. Mem. Torrey Bot. Club. 12(3): 227-228. Woronin, M. 1861. "Recherches sur !es algues marines. Acetabularia Lamx. et Espera Done." Ann. Sci. Nat. Bot. 4(16) :200-14. Notes on the Fringed Pipefish, Micrognathus crinigerus, From the West Coast of Florida CHARLIE R. POWELL Department of Zoology, The University of Texas and KIRK STRAWN Department of Zoology, The University of Arkansas Abstract Occurrences of eggs, embryos, and sizes are reported for collections of the fringed pipefish, Micro· gnathus crinigerus, made at Cedar Key and Old Tampa Bay, Florida from 1950 to 1957. M. crinigerus had the shortest breeding season of any syngnathid commonly found on the grass flats, breeding from April 2 to September 16. Lengths and numbers of eggs and embryos were similar for males and females. The sex ratio varied with season. Introduction The fringed pipefish, Micrognathus crinigerus (Bean and Dresel), is a small, little known fish, which ranges from Miami, Florida to Cameron, Louisiana and is found at Royal Island, Bahamas (Herald, 1942). There are doubtful data on one specimen from Albrolhos Island, Brazil (Herald, 1942) . It lives and breeds in the shallow grass flats. Collections made from the West Coast of Florida are reported as evidence for some con­clusions about the life history of the species. Methods The fish were caught in push nets, beam trawls, and dip nets while collecting Hippo· campus zosterae Jordan and Gilbert during the years 1950 to 1957. Specimens were measured, sexed, and their eggs or embryos examined. Individuals with brood pouches were considered males. No pouched males under 60 mm were taken (Fig. 1). Females as small as 45 mm were recognized by microscopic inspection of intact ovaries. The smallest fish were not sexed. Most unsexed fish between 53 and 60 mm (Fig. 1) probably were males too young to have brood pouches. Prior to counting, embry·os of M. crinigerus were removed from the males by spread­ing the right and left flaps of the brood pouch and teasing out the embryos. Eggs were counted in the intact ovaries. Ovaries were removed from the body cavity of the female by making an incision along the right side from the vent to the region of the pectoral fin. They were lifted out with the head of a pin and severed from the fish at the urogenital opening. The ventral body wall, the dorsal surface of the brood pouch, and the adjacent flap of the brood pouch are dented by cup-shaped depressions which hold individual embryos in place. The embryos are arranged in the brood pouch of the male in one, two, three, or, if Fringed Pipe fish, Micrognathus crinigerus, from the West Coast of Florida 113 90 85 80 75 65 60 " " .. El ~ fj .. fib " El So " t ""' ., " El ~ ~ " D " t fl] Ii! " "° Id El " ~ !'P " "" " " ~ " " " be f"l c ~ "" "" ~ • t " ~ ""' • • .., L .. "" " ..," 0 " p~ " • " " " " • • I• • I• 0 I" • -• I ""• Fie. 1. Seasonal lengths of Micrognathus crinigerus at Cedar Key, Florida. Unsexed fish are rep­resented by black squares, females by crosshatched squares, and males by clear squares. A dot in the square either indicates yolked eggs in females or embryos in males. the embryos are numerous, in four rows. One and two rows are arranged horizontally. More rows frequently result in a staggered vertical arrangement of embryos. The pos­terior ends of the right and left ovaries are fused into a common chamber. The anterior two-thirds to three-fourths of the maturing ovaries are separate, are equally developed, and contain yolked eggs arranged vertically in one to three rows. A horizontal row may be added when eggs are numerous. Unyolked eggs are on the ventral surface of the ovary. Results The distributions of specimens by size and according to sex breeding condition are given in the chronological graph in Fig. 1. The number of eggs is related to the cube of the length in Fig. 2 (Nicholls, 1958). Most large specimens of M. crinigerus were collected in the summer. The scarcity of these fish during the winter may indicate that M. crinigerus like H. zosterae (Strawn, 1958) survives only one winter and that the largest individuals are between seven and seventeen months of age. On the West Coast of Florida M. crinigerus is common in Sar­gassum floating in channels. It is similar to the pigmy seahorse, H. zosterae, in its inti­mate association with plants. It twists its body around plants and assumes a range of colors matching the colors of plants among which it lives. Sex ratio varied with season. Between the vernal and autumnal equinoxes 26 males and 30 females of M. crinigerus over 65 mm in length were taken. Between the autumnal and vernal equinoxes 2 males and 14 females 65 mm or longer were collected. These sex 114 Fringed Pipe fish, Micrognathus crinigerus, from the W'est Coast of Florida 70 60 50 40 30 (/) 0 >­ a:: al ~ w 20 a:: 0 (/) w 10 0 u.. a:: w al ~ ::::> z 0 !? r! ~ '~ ,2 !? o~ ' ~ ' ' ' ' ~ 6 d ~ '~ 02~ o" d ~ r! !? ~ r! 6 ' ' !? 6 r! !? !? !? 6 !?dd 6 !? ' 6 I l ~ !? ro (>I (J1 C1> --.I Q) 0 0 0 0 0 0 ""' 0 0 0 0 0 0 ~o ~o ~o ~o 0 ~o 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 3 (LENGTH IN MM) F1G. 2. Egg and embryo counts made on Micrognathus crinigerus from Cedar Key and Old Tampa Bay. The length in mm was cubed because egg number increases as the cube of the length for most fishes (Nicholls, 1958). Only males with undamaged pouches and females with medium to large sized eggs are used in this figure. Solid symbols represent Old Tampa Bay fish ; open ones represent Cedar Key fish. When the symbol represents more than one fish, the number is given to the right of the symbol. distributions gave a x2 value of 4.7 and differ at the 0.05 significance level. Strawn (1958) found a reverse seasonal sex distribution in H. zosterae. Males of H. zosterae were about as abundant as females in winter collections and were greatly outnumbered by females in most summer samples. The lengths of the two sexes appeared similar (Fig. 1). The largest individual was a Fringed Pipe fish, Micrognathus crinigerus, from the West Coast of Florida US female in seven out of thirteen collecting periods that yielded both sexes. The sympatric syngnathid, H. zosterae, also had males and females of similar size, but Syngnathus scovelli (Evermann and Kendall) had females that average much larger than the males. M. crinigerus had the shortest breeding season of any syngnathid commonly found on the grass flats. Pregnant males were taken at Cedar Key from April second through Sep­tember first and females with yolked eggs from April second through September six­teenth (Fig. 1). Reid (1954) collected breeding males in May, August, and September. The breeding season of M. crinigerus appeared shorter than that of H. zosterae in the Tampa Bay area. A collection of H. zosterae made south of the west end of Gandy Bridge, Old Tampa Bay, Pinellas County, Florida on February 17 and 18, 1951 con­tained many females with ripe eggs and numerous pregnant males. However, none of six large female M. crinigerus taken in the collection had yolked eggs and none of five large males was pregnant. Females with large eggs and pregnant males of M. crinigerus were taken at this locality on March 27, 1951. H. zosterae, at Cedar Key, starts breeding in February and stops in October (Strawn, 1958). S. scovelli breeds all year at Cedar Key (Reid, 1954). Reid (1954) collected either females with yolked eggs or pregnant males of Syngnathus fioridae (Jordan and Gilbert) during all months. The breeding season of H. zosterae appears correlated with number of hours of sunlight per day rather than with temperature (Strawn, 1958). Data in Fig. 1 suggest a similar correlation for M. crinigerus. The smallest male containing embryos was 65 mm. During the breeding season 20 out of 26 Cedar Key males 65 mm or over contained embryos. Twenty-six of thirty Cedar Key females, 65 mm or larger, taken during the breeding season, contained yolked eggs. Only three females below 65 mm (two 63 mm and one 59 mm) had yolked eggs. The number of large yolked eggs in a female was similar to the number of embryos in a male. Tampa Bay fish were larger and contained more eggs and embryos (Fig. 2). The number of embryos in the pouches of Cedar Key males varied from 23 to 47 and the number of large eggs in females varied from 2 to 50. Embryo number varied from 14 to 54 in Tampa Bay males and the number of medium to large eggs varied from 19 to 68 in Tampa Bay females. The two large eggs in the 72 mm Cedar Key female (Fig. 2) probably were not discharged during breeding and did not represent a full batch of eggs. Fecundity varied with the season in samples of S. scovelli (Joseph, 1957) and in H. zosterae. Seasonal variations in the fecundity of M. crinigerus undoubtedly oc­curred and add to the variation in embryo and egg numbers seen in Fig. 2. However, samples were too small to observe differences among them. Collections made at Cedar Key in September of 1958 yielded no specimens of M. crinigerus. Springer and Woodburn ( 1960) found none in the Tampa Bay area following the severe winter of 1957-1958. This coldest winter in 50 years (Springer and Wood­burn, 1960) may have destroyed the populations in these areas. Other Species Other syngnathids commonly found on the grass flats, the dusky pipefish, S. fioridae, and the gulf pipefish, S. scovelli, are less specialized for clinging to plants and for matching the various colors of the surrounding plants. Two more syngnathids, the spotted seahorse, H. erectus Perry, and the chain pipefish, S. louisianae Gunther were 116 Fringed Pipefish, Micrognathus crinigerus, from the West Coast of Florida sometimes found on the grass flats but appeared to be strays from deeper water. In extensive collecting of intertidal areas on the coast of North Carolina, Florida, and Texas the second author has taken no pouched males of S. louisianae. Springer and Woodburn ( 1960) in their study of the fishes of the Tampa Bay area took only one recognizable male of S. louiswnae (a non-pregnant individual). Literature Cited Herald, Earl Stannard. 1942. Three new pipefishes from the Atlantic Coast of North and South America, with a key to the Atlantic American species. Stanford Ichthyol. Bull. 2 ( 4) : 125-134. Joseph, Edwin B. 1957. A study of the systematics and life history of the gulf pipefish, Syngnathus scovelli (Evermann and Kendall). Dissertation Absts. 17(5): 1159. Nicholls, A.G. 1958. The egg yield from brown and rainbow trout in Tasmania. Aust.]. Mar. Freshw. Res. 9 ( 4) : 526-536. Reid, George K. 1954. An ecological study of the Gulf of Mexico fishes, in the vicinity of Cedar Key, Florida. Bull. Mar. Sci. Gulf Caribb. 4(1) : 1-94. Springer, Victor G., and Kenneth D. Woodburn. 1960. An ecological study of the fishes of the Tampa Bay area. Professional Papers Series, No. 1. Fla. State Board of Conservation. 104 p. Strawn, Kirk. 1958. Life history of the pigmy seahorse, Hippocampus zosterae Jordan and Gilbert, at Cedar Key, Florida. Copeia 1958 ( 1) : 16-22. Cell-Diameter Frequency Distributions of the Planktonic Diatom Rhizosolenia alata ROBERT A. wOODMANSEE Biology Department, University of Southern Mississippi, Hattiesburg, Mississippi, and Gulf Coast Research Laboratory, Ocean Springs, Mississippi Abstract The dispersal pattern for Rhizosolenia alata in inshore waters of Mississippi is presented. Cell­diameter_frequency distributions of samples taken at various times in Biloxi Bay and Mississippi Sound during a post-bloom situation in the summer were compared by the chi-square test. The wider Rhizosolenia alata remained in the surface layer and were transported toward the sea while the nar­rower cells settled to be transported landward. Rhizosolenia alata was the most numerous species of the genus and was found to increase in abundance as the salinity increased. Rhizosolenia setigera and Rhizosolenia stolterfothii showed maximum concentrations in the intermediate salinities of the Bay. Introduction An attempt has been made to follow the dispersal of Rhizosolenia alata by comparing the cell-diameter frequency distributions of samples taken at various locations in the inshore waters of the Mississippi coast. Knowledge of the drift-distribution of popula­tions in estuarine situations, in addition to its intrinsic value, permits an evaluation of the influence of these drifts on studies of seasonal distribution. Bandel (1940) has con­sidered the colonization of the Darss Sill region of the Baltic by Rhizosolenia from the more saline Kattegat and North Sea. Hulburt (1956) commented on diatoms entering Great Pond from Vineyard Sound, and Simmons and Thomas (1962), recognized a river association and a Gulf association of diatom species and discussed the mixing of these associations off the Mississippi Delta. However, in none of these works were the derived populations actually matched with populations from the assumed place of origin. If the cell-diameter frequency distributions of the populations in question are compared, one can evaluate statistically the liklihood of one population being derived from another and can further deduce how the population may have been altered during horizontal transport. In addition to dispersal the question of salinity tolerance is quantitatively considered. Gran (1905), Hustedt (1930), Cupp (1943), Freese (1952), Curl (1959), and others have categorized various species as "brackish," "neritic" or "oceanic," but have not attempted to determine any more exact relationship on the basis of field data, although Curl and McLeod (1961) have determined in the laboratory the effect of salinity on the rate of photosynthesis in Skeletonema. Davis Bayou, Biloxi Bay and Mississippi Sound were investigated (Fig. 1). They are shallow, turbid, stained and of low transparency. The bottom is a soft mud. General de­scriptions of the area of investigation may be found in the work of Priddy et al. (1955) and Moore (1961). 118 Frequency Distributwns of the Planktonic Diatom Rhizosolenia alata 0 I 2 SCALE OF MILES MISSISSIPPI SOUND +3.5m FIG. 1. The area of investigation. The Bayou, Bay and Sound stations are marked by crosses. The location of the Gulf Coast Research Laboratory (GCRL) is indicated. Methods FIELD AND LABORATORY PROCEDURES From mid-June through July, 1955, plankton collections and hydrographic measure­ments were made at 3 locations along a salinity gradient in Mississippi coastal waters (see Fig. l). Determinations were made of temperature, salinity, dissolved oxygen and dissolved orthophosphate at suitable depth intervals. Secchi disc readings were made at all stations. Oxygen determinations were made by the Winkler method. Orthophosphate determi­nations were made colorimetrically by the stannous chloride method given in Standard Methods for the Examination of Water and Sewage (1946). The high concentration of suspended particles in the water made it usually necessary to filter the samples. In view of the concentration of a yellow dissolved substance in the water, the filtered sample was compared colorimetrically to a distilled water reagent blank before and after treatment with reagents. The difference between the readings was taken as a measure of the phos­phate concentration. A 4-inch white Secchi disc was used for transparency measure­ments. At first, samples for plankton analysis were collected by pouring a known volume of water through a No. 12 net. This procedure proved to be impractical because the small quantity of plankton present was inadequate for statistical study. Later plankton collec­tions were made by pulling the net horizontally through the water about 16 meters. If the net were 100% efficient, a 16 meter drag would sample about 700 liters of water. The per cent efficiency of the net has been estimated by employing both of the above methods at the same time and found to be about 50%. Many of the samples were further concentrated in the laboratory prior to counting. An aliquot, usually about 0.09 ml, of each sample was placed on a slide and a coverslip added. The mount was sealed with fingernail polish to prevent drying. Counts were made and the numbers counted translated to numbers per liter. Six species of Rhizosolenia have been encountered in the study. Two of these, R. rilata and R. setigera were sufficiently numerous to permit an evaluation of distribution. R. alata was probably the more numerous and was certainly of more general occurrence. R. alata is a rather variable species made up of the type and 3 forms. In this study the type and 2 forms (gracillima and indica) have been encountered. Form gracillima was very common while form indica was relatively scarce. The distinction between form gracillima and the type is one of cell diameter. The cell diameter of the type varies from 7-18 microns and that of form gracillima is 7 microns or less according to Cupp ( 1943). Since measurements of cell diameters do not show a clear-cut separation between form gracillima and the type, all R. rilata having a cell diameter of 3-15 microns have been designated simply as R. rilata. This procedure is consistent with the approaches of Schiitt (1886) and Wimpenny (1936) and consistent with the findings of Margalef (1957). In this paper, then, all reference to R. alata excludes form indica, which is distinct and is considered separately. STATISTICAL PROCEDURES For each sample either 100 cells were counted or cell counts were continued until 0.16% of the sample had been counted. The criterion of counting 100 individuals of a given species was established by Winsor and Walford (1936) and has been used by Winsor and Clarke (1940). The criterion of counting 0.16% of the sample provides that the mean percent deviation from the mean of 10 successive counts will be 12% for population densities of about 90,000 per liter (Littleford, Newcombe and Shepherd, 1940). The value of 0.16% is derived from their data for a counted volume of 0.024 ml from a concentrated sample of 15 mls. The population densities encountered here are considerably lower than 90,000 per liter, which was the lowest density given by Little­ford, et al. (1940); however, the duplicate aliquots examined in order to count 0.16% of the sample were in good agreement. Since many of the Rhizosolenia were broken in half and often only one valve was visible in the area being counted, the valves were counted and thi.s number was divided by two to get the number of cells counted. The chi-square test was used to determine whether or not two cell-diameter frequency distributions represented samples of the same or different populations. The linear cor­relation coefficient was employed to determine the extent to which two cell-diameter frequency distributions were similar. In the chi-square comparison the following procedures were employed: 120 Frequency Distributions of the Planktonic Diatom Rhizosolenia alata 1. When single samples were being compared, the actual number counted in each cell diameter was used in the usual "observed" column. The corresponding values of the "expected" column were obtained by multiplying the numbers counted in each cell di­ameter by a factor which would make the total of the expected column equal to the total of the observed column. An example of a chi-square calculation of this type is shown in Table 1. 2. When cell-diameter frequency distributions were combined, the average number per liter was determined for each cell diameter and then these values were multiplied by a factor which, in the case of the observed column, would make the total number equal to the total number counted in all the samples involved in the combination; and in the case of the expected column, would make the total number equal to the total number in the observed column. An example of a chi-square calculation of this type is shown in Table 2. 3. When the expected frequency was less than 5 for a cell diameter, diameter classes were combined. 4. In order to make all comparisons comparable, the sample in which the smaller number was counted was placed in the observed column. If the chi-square value was less than the value at the 0.05 or 5% probability' level in the "Accumulative Distribution of Chi-square" table (Snedecor, 1956), the two samples being compared were considered to be components of the same population. If the chi- TABLE 1 Chi-square calculation for the comparison of the cell-diameter frequency distributions of the Rhizosolenia alata populations sampled on June 18 in the Sound at the surface ( MS-S) and on June 23 in the Bay at the surface (BB-S). 0 = obsen-ed, E =expected, d.f. = degrees of freedom, P = probability of a higher chi-square value being obtained from two samplings of the same population June 18 MS-S vs. June 23 BB-S 47.0 cells measured from the June 18 MS-S sample 85.0 cells measured from the June 23 BB-'S sample 0 June 18 June 23 Cell-diameter MS-S BB-S in microns #measured #measured 3 17.0 23.5 4 4.5 16.0 5 6.0 15.5 6 11.5 21.0 7 1.5 0.5 8 2.0 3.5 9 1.5 1.5 10 2.0 11 0.5 0.5 12 2.0 1.0 13 14 0.5 7-14 8.0 9.0 Total 47.0 85.0 June 23 BB-S x 0.553 E 13.0 9.0 8.5 11.5 .5 2.0 1.0 1.0 .5 .5 5.0 47.0 0-E 4.0 -4.5 -2.5 .0 3.0 (O-E)2 16.00 20.25 6.25 .00 9.0 (O-E)2 E 1.231 2.250 .736 .000 1.800 6.017 47.0 Factor: --= 0.553 85.0 For d.f. = 4 and for P of 0.05, x2 = 9.49; 6.02 <9.49; therefore, these samples are from the same population. For x2 of 6.02,P = 0.20 or 20%. Frequency Distributions of the Planktonic Diatom Rhizosolenia alata 121 TABLE 2 Chi-square calculation for the comparison of the cell-diameter frequency distribution of Rhizosolenia alata populations A and B. The derivations of populations A and B are given. MS-B = Sound at the bottom, BB-B = Bay at the Bottom. Other abbreviations are the same as in Table 1 A vs. B June 18 MS-'S +June 18 MS-B -----------+ June 23 BB-S 2 A=-----------------­ 2 July 8 BB-S + July 8 BB-B B=---------­ 2 A total of 166.0 cells measured from population A A total of 88.5 cells measured from population B Cell-diameter in microns B # / L 0 88.5 Bx -282 A # / L E 88.5 Ax­533 0 -E (O­E)2 (O-E)2 E 3 4 5 6 118 50 48 39 37.0 15.5 15.0 12.0 176 73 81 131 29.0 12.0 13.5 21.5 8.0 3.5 1.5 -9.5 64.0 12.25 2.25 90.25 2.205 1.02 .167 4.195 7 8 5 9 1.5 3.0 9 20 1.5 3.5 -0.5 .25 .05 9 10 11 12 13 14 5 4 4 1.5 1.5 1.5 16 7 4 14 2 2.5 1.0 .5 2.5 .5 - 2.5 6.25 .893 Total 282 88.5 533 88.0 8.53 For d.f. = 5 and for P of 0.05, x2 = 11.07; 8.53 <11.07; therefore, these samples are from the same population. For x2 of 8.53, P = 0.13 or 13%. square value was greater than the value at the 0.05 probability level, the two samples being compared were considered as different populations. For each cell-diameter fre­quency distribution comparison made in the discussion, the percent probability of a higher chi-square value being obtained from two samplings of the same population is given. The similarity of the two frequency distributions is, then, directly proportional to the probability value. Physico-Chemical Data The salinities at the surface and at the bottom in the Sound, Bay and Bayou are shown in Fig. 2 and the density profiles are shown in Fig. 3. The salinities encountered varied from 14.5 to 28.8 %o. The water column was stratified in the latter part of June, mixed in early July, stratified on July 23 in the Bay and then mixed again on July 31 in the Sound. Fresh-water discharge into Biloxi Bay has been estimated by adding the flows recorded for the Biloxi and Tchoutacabouffa Rivers (Fig. 4) . The discharge of the Biloxi River was measured at Wortham, Mississippi, and the Tchoutacabouffa discharge is taken from a gauge located on Tuxachanie Creek near Biloxi. Tuxachanie Creek is a tributary 122 Frequency Distributions of the Planktonic Diatom Rhizosolenia alata 14 16 18 z ...J ­ ~ u w ~ 5 ~ 1000 r w SOUND -• 0 3 r w "' >­ ~ F IG. 4. A daily record of fresh-water discharge in hundreds of second-feet into Biloxi Bay from the Biloxi and Tchoutacabouffa Rivers. The dis­charge of the Biloxi River was measured at Wor­tham, Mississippi, and the Tchoutacabouffa dis­charge is based upon a gauge located at Tuxa­chanie Creek, which is a tributary of the Tchouta­cabouffa. Average phosphate concentrations for the water column in Biloxi Bay and Mississippi Sound are ind'cated by crosses and expressed as microgram-atoms per liter. made up very largely of Skeletonema costatum. The minimum oxygen saturation was 52% and occurred at the minimum bottom salinity encountered. The P04 values (Fig. 4) were quite low, frequently zero, and when the reading was positive it was open to some question because the typical blue color almost never oc­curred. The greatly increased river discharge in mid and late July did not bring about an increaEe in the phosphate content of the water in the Bay and Sound. The phosphate concentration was zero before the discharge began and was zero during the discharge. The Secchi disc readings varied from 38 to 107 cm. Dispersal of Rhizosolenia alata The concentrations of Rhizosolenia alata in the surface and bottom waters of the Sound and Bay are shown in Fig. 5. The maximum concentration of 948 cells per liter was encountered at the beginning of the study period on June 18 at the surface in the Sound. Cell-diameter frequency distributions are shown for the samples taken in Sound surface waters (Fig. 6), Sound bottom waters (Fig. 7), Bay surface waters (Fig. 8), and the Bay bottom waters (Fig. 9). POPULATION GROUPINGS The June 18 maximum (Fig. 6) is characterized by peaks of 3-micron and 6-micron cells. There are two other samples which show a 3-micron and 6-micron peak. These are the samples taken on June 18 at the bottom in Mississippi Sound and on June 23 at the surface in Biloxi Bay with the concentration of the former being 260 cells per liter and that of the latter being 458 cells per liter. It is accordingly assumed that the bloom was centered in the Sound and extended into the Bay, where it was developed to about one­half the concentration found in the Sound. A chi-square test clearly indicates that the JUNE IB­JULY 4 -­JULY 31 ----­ 16 FIG. 6. Cell-diameter frequency distribution of the Rhizosolenia alata populations sampled in the surface waters of Mississippi Sound on the dates indicated. 000 "" 16 JUNE l8­ JULY JULY 31 ----­ I Fie. 10. A diagrammatic section along the salinity gradient with the locations of the Bay and Sound stations and the presumed transport of the three components of population A (the surface and bottom samples in the Sound on June 18 and the surface sample in the Bay on June 23) indi­cated. The late June locations of these three components are indicated by the dates and the pre­sumed transport indicated by the arrows. The 1.016 isopycnal for the late June period is shown by a dashed line. The presumed location of derived population A-C or B is indicated for early July just prior to vertical mixing. The origin of population (A-B X 1.35) or C is indicated. See the text for further explanation. 150 Cl'. w 1-­:::i Cl'. w l'.l. "' _J _J w u 100 50 4 CELL 6 DIAMETER 8 10 IN 12 MICRONS 14 Fie. 11. A comparison of the cell-diameter frequency distributions of 4 derived Rhizosolenia alata populations. See the text for the derivation of these populations. Frequency Distributions of the Planktonic Diatom Rhizosolenia alata 127 DISPERSAL PATTERN A dispersal pattern for population A may be proposed if one assumes the usual estu· arine two-layered circulation in conjunction with a more rapid settling of the narrower cells. The narrower, particularly the 3-micron, cells of population A are assumed to have settled into the bottom waters and to have been transported into the Bay to make up a significant part of population B (Fig. 10). The frequency distribution of populations A and Bare in general similar (r = 0.94: 13% probability of a higher chi-square value), but the July 8 curve shows fewer cells in every diameter suggesting a loss of cells during transport into the Bay (Fig. 11) . The concentrations in each cell diameter for the popu· lation B curve have been multiplied by 1.35 so that the relative differences between the two distributions may be more clearly seen (Fig. 11). A comparison of BX 1.35 with A shows that population A is markedly different from population B only in the case of the 6-micron cells, which are much more numerous in population A. This difference suggests that the 6-micron cells are not settling out as rapidly as the other cells; an inference which may also be drawn from the surface Sound samples (Fig. 6). If one subtracts derived population B X 1.35 from population A, the difference should be that part of population A which did not sink and move into the Bay. This derived popu· lation (A -B X 1.35) shows a great deal of resemblance to population C. Population C is compared to population (A -B X 1.35) in Fig. 12, where the agreement is seen to be fairly good. The correlation coefficient of 0.90 indicates considerable similarity although the chi-square value is high enough ( < 0.5% probability of a higher value) to indicate that the two populations are not the same. The main difference between the two curves is found in the numbers of cells of larger diameters found in population C. These larger cells have almost certainly been brought into the area from farther out the salinity gradi· ent and it is the addition of these larger cells which has caused the high chi-square value. 100 ­ ::; ­ ::; ffgehalt der Ostsee im Gebiet der Darsser Schwelle. Int. Rev. Hydrobiol. 40: 249-304. Cupp, E. E. 1943. Marine plankton diatoms of the west coast of North America. Bull. Scripps Instn. Oceanogr. 5: 1-238. Curl, H. C., Jr. 1959. The phytoplankton of Apalachee Bay and the northeastern Gulf of Mexico. Puhl. Inst. Mar. Sci. Univ. Tex. 6: 277-320. Curl, H., Jr., and G. C. McLeod. 1961. The physiological ecology of a marine diatom, Skeletonema costatum (Grev.) Cleve. J. Mar. Res. 19: 70-88. Davis, C. C. 1950. Observations of plankton taken in the marine waters of Florida in 1947 and 1948. Quart. J. Fla. Acad. Sci. 12: 67-103. Freese, L. R. 1952. Marine diatoms of the Rockport, Texas, Bay area. Tex. J. Sci. 4: 331-386. Gran, H. H. 1905. "Diatomeen." In Brandt und Apstein, Nordisches Plankton, Botanischer Tei], 19: 1-146. Leipzig, Lipsius und Tischer. Gr~ntved, Jul., and E. Steemann Nielson. 1957. Investigations on the phytoplankton in sheltered Danish marine localities. Medd. Komm. Danm. Fiskeri-og Havunders., Serie Plankton, Bd. 5 ( 6) : 1-52. Gross, F., and E. Zeuthen. 1948. The buoyancy of plankton diatoms: a problem of cell physiology. Proc. roy. Soc. 135: 382-389. Hulburt, E. M. 1956. The phytoplankton of Great Pond, Massachusetts. Biol. Bull. 110: 157-168. Hustedt, F. 1930. Die Kieselalgen Deutschlands, Oesterre'.ches und der Schweiz. Kryptogamenflora, 7: Part I, secs. 1-5, 920 pp. Littleford, R. A., C. L. Newcombe, and B. B. Shepherd. 1940. An experimental study of certain quantitative plankton methods. Ecology 21: 309-322. Margalef, Ramon. 1957. Fitoplancton de las costas de Puerto Rico. Invest. Pesq. 6: 39-52. Moore, D. R. 1961. The marine and brackish water Mollusca of the state of Mississippi. Gulf Res. Rept. 1 : 1-58. Prasad, R. R. 1954. The characteristics of marine plankton at an inshore station in the Gulf of Mannar near Mandapam. Indian J. Fish. 1: 1-36. Priddy, R.R., R. M. Crisler, C. P. Sebren, J. D. Powell, and H. Burford. 1955. Sediments of Missis­sippi Sound and inshore waters. Bull. Miss. State Geo!. Sur. 82: 1-54. Riley, G. A., Henry Stommel and D. F. Bumpus. 1949. Quantitative ecology of the plankton of the western North Atlantic. Bull. Bingham oceanogr. Coll. 12: 1-169. Ryther, J. H., and E. M. Hulburt. 1960. On winter mixing and the vertical distribution of phyto­ plankton. Limnol. and Oceanogr. 5: 337-338. Schiitt, Franz. 1886. Auxosporenbildung von Rhizosolenia alata. Ber. dtsch. bot. Ges., Bd. 4: 8-14. Simmons, E. G., and W. H. Thomas. 1962. Phytoplankton of the eastern Mississippi Delta. Pub!. Inst. Mar. Sci. Univ. Tex. 8: 269-298. Snedecor, G. W. 1956. Statist;cal methods applied to experiments in agriculture and biology. 5th ed. Iowa State College Press, Ames, Iowa. 534 pp. Steele, J. H., and C. S. Yentsch. 1960. The vertical distribution of chlorophyll. J. Mar. b:ol. Assn. U.K. 39: 217-226. Wimpenny, R. S. 1936. The size of diatoms. I. The diameter variation of Rhizosolenia styliformis Brightw. and R. alata Brightw. in particular and of pelagic marine diatoms in general. J. Mar. biol. Assn. U.K. 21: 29-60. Winsor, C. P., and G. L. Clarke. 1940. A statistical study of variation in the catch of plankton nets. J. Mar. Res. 3: 1-34. Winsor, C. P., and L. A. Walford. 1936. Sampling variations in the use of plankton nets. J. Cons. Int. Exp!. Mer. 11: 190-204. Distribution of the Zooplankton in the Salt Marshes of Southeastern Louisiana1 RENE P. CuzoN nu REsT2 Institute of Marine Science, Port Aransas, Texas Abstract A plankton survey was made at 15 stations in the salt water marshes of southeastern Louisiana from July 1959 to March 1961. The physical and chemical parameters including temperature, oxygen, salinity, turbidity and inorganic phosphate, were measured concurrently. In the study area, which ranged from nearly fresh to nearly marine waters, one species of copepod, Acartia tonsa, dominated the zooplankton with 145,000 per five minute haul and was abundant throughout the year. There were few other populations. Numerically important copepod species were Eurytemora hirun­doides, Pseudodiaptomus coronatus, Paracalcmus crassirostris, and Oithona spp. Meroplanktonic elements such as nauplii and zoeae of Cirripedia also attained numerical importance. Fresh water and marine faunas were localized and in minor numbers. A major zooplankton out­burst occurred in April 1960. No comparable increase was recorded at any other time. Populations were more numerous in open water than in bayou samples. Smallest numbers were found in October. Introduction In 1958 the Corps of Engineers began constructing a ship channel between New Orleans and the Gulf of Mexico across marshes valuable for fisheries resources such as shrimp, crabs, oysters, and food fish, and for fur-bearing animals such as muskrats and nutria. In order to determine the potential effects of the channel on the flora and fauna in the project area, a contract was made between the Fish and Wildlife Service and the Texas A. & M. Research Foundation. Under this contract the Department of Ocean­ography and Meteorology at the A. & M. College of Texas collected samples of the aquatic fauna to determine natural fluctuations in their distribution and the range of hydrological conditions under which they lived. This plankton survey was part of the overall study. Data on the type and abundance of the plankton in the region were previously nonexistent. DESCRIPTION OF THE PROJECT AREA The project area covered some 700 square miles, comprising a complex system of lakes, bayous, and marshland spreading from the almost fresh water of Lake Pontchar­train in the north to the marine conditions of Breton and Chandeleur Sounds to the south. The project area was located in the Mississippi Delta region, east of the river following the alignment of the planned ship channel. The 70-mile long channel starts at a point where it connects with the Inner Harbor Navigation Canal of New Orleans 1 From a Thesis submitted to the Graduate School of the Agricultural and Mechanical College of Texas in partial fulfillment of the requirements for the degree of Master of Science in Biological Oceanography. Work was aided by a contract from the U. S. Fish and Wildlife Service with the Texas A. & M. Research Foundation No. 14-17-008-119. 2 Present address: National Oceanographic Data Center, Washington, D. C. (Industrial Canal) and runs almost due east for more than five miles, following the lntracoastal Waterway. From this point the Channel skirts the southwestern shore of Lake Borgne and traverses Bayou La Loutre ridge in a southeasterly direction across the Mississippi Delta to the open Gulf by way of Breton and Chandeleur Sounds (see Fig. 1). The basic geology of the region was investigated by Russell (1936), and Treadwell (1955). Relative to the land, the water level has been rising steadily in the area (O'Neil, 1949) . Three explanations have been offered for this phenomenon: 1) compaction of the sedi­ments; 2) depression of the earth's crust by the sediment load of the river; and 3) the FIG. 1. Chart showing the station locations and boundaries of the three sub-areas in the Mississippi River-Gulf outlet project area. Zooplankton in the Salt Marshes of Southeastern Louisiana eustatic change of sea level (Gunter, 1952; and others). The subsidence has been ac­celerated somewhat by the construction of levees. The type of vegetation covering the marshland and levees was related to the height of permanent water table. Trees were growing on high land while the lower land supported marsh vegetation (Treadwell, 1955). In general, there was a gradual change in flora from salt water to fresh water habitats. Many plants, however, thrived in several en­vironments and were found in fresh, salt or brackish waters. Further detail on the eastern Louisiana marsh vegetation was given in the works of Penfound and Hathaway (1938). On the basis of a progressive increase in salinity, the project area was divided into three sub-areas (see Fig. 1) including the nearly fresh waters of Bayou Dupre (sub­area 1), waters of intermediate salinity (sub-area 2) , and those of Breton and Chan­deleur Sounds (sub-area 3), where nearly marine conditions prevailed. Lakes and bayous were generally less than ten feet in depth. In each sub-area five stations were selected representing lake, bayou, and intermediate conditions. Materials and Methods A field laboratory was established at Hopedale, Louisiana, from which the sampling program was conducted. From July 1959 to August 1960, each sub-area was sampled three times a month except for August 1959 when sampling took place only in the first week. No samples were taken in September 1959. From September 1960 to March 1961, each sub-area was sampled twice monthly. Twenty-five to forty-eight samples were taken per station-a total of 617. FIELD TECHNIQUE Sampling was effected from the M/V Maggie, a 24-ft cabin cruiser. The zooplankton was collected with a nylon net of standard design with a detachable brass bucket at the cod-end. It had a mouth diameter of 0.50 m and a length of 1.60 m. The netting had a mesh aperture of approximately 0.239 mm (#6). Use of a #8 net was abandoned in favor of the coarser #6 net in an attempt to decrease the amount of suspensoids other­wise present in considerable amount in some samples. Samples in July and October 1959 were obtained with a 0.203 mm (#8) net. All the hauls were of five-minute duration and were made in daylight at the surface from the stern of the vessel. Towing speed was about two knots. At the bayou stations plankton nets usually were towed in the center of the bayous following their contours. At lake stations the hauls were made in a circular pattern. The catch was then preserved in 5 per cent formalin neutralized with borax. No attempt was made to estimate the volume of water that passed through the net. At times, clogging interfered with the proper operation of the net, thus reducing the amount of water filtered. Considerable amounts of detrital material either floating at the surface or in suspension in the water precluded the use of any flow meter. The impeller would not have functioned reliably and erroneous conclusions might have been drawn as to the actual volume of water filtered. Effort was made, however, to keep the towing time and speed as consistent as possible. The net was rinsed with great care between the hauls to prevent contamination of the samples from one station to the next. After the contents of each haul had been emptied in a sampling bottle, the bucket was rinsed with a hose to detach any organisms trapped in the wire mesh window. The window was subsequently cleaned with a toothbrush to ensure maximum filtering capacity. During the course of the plankton survey, examination of the net mesh under a microscope revealed a progressive narrowing in the mesh opening due to the slow deposition of organic material. To prevent excessive decrease in mesh size, the net was left soaking overnight at fortnightly intervals in soap suds, rinsed and brushed after complete drying. LABORATORY TECHNIQUE Before the enumeration of the sample content, the liquid lying above the zooplankton in the sampling vial was partially poured out. The balance of the sample which contained some liquid and the zooplankton was then transferred to a conical pharmaceutical graduate varying in size from 25 to 250 ml and indicating the sample volume to the nearest ml. The sample was allowed to settle for approximately 30 minutes before the volume \\"as determined. Few true plankton volumes were obtained because, in many of the samples, detrital material sometimes represented a volume several times that of the actual plankton sample. The volume was thus only an index to the desirable dilution. Proper dilution was obtained after vigorous agitation when one ml of the sample provided approximately 250 organisms. As a check on the dilution factor, a grid of about 64 cm2 was placed under the counting dish. After the aliquot was distributed over the counting dish as evenly as possible, a few squares were counted at random. This provided a quick approximation of the total numbers. If the first aliquot gave sufficient numbers, the sample was counted immediately, otherwise more aliquots were added. In those samples where the total number of specimens was less, or only· slightly more than 250, all the specimens were enumerated. The plankton was examined under 20X power. Specimens appearing for the first time were dissected and drawn for future reference after being observed under 470X power. The morphological characteristics were then compared to a model specimen to establish the proper identification. All the copepodites were assigned to a species, a genus, or to a well-defined order or sub-order. No attempt was made to identify the nauplii. The monographs of Sars ( 1903, 1918) have been used extensively as taxonomic ref· erences. Other references included Wilson ( 1932a and b) , Rose ( 1933), Pratt (1935), Biickmann (1945), Farran (1948), and Wilson (1958). Pennak (1953) and Ward and Whipple (1959) also were used to identify the fresh water specimens. HYDROGRAPHIC METHODS Coincident with each plankton haul, a series of hydrographic samples were taken at the surface and at a depth of five feet for determinations of salinity, dissolved oxygen, inorganic phosphates, pH, and turbidity. Temperatures were taken at the surface of the water only, from a bucket sample and measured to the nearest 0.1 °C. Salinity observations were determined by standard Mohr techniques as chlorosity and converted to salinity. Turbidity readings were made in a Klett colorimeter with a blue filter, calibrated with distilled water to which known amounts of suspensoids had been added. Zooplankton in the Salt Marshes of Southeastern Louisiana Oxygen was determined by a modified Winkler method, full description of which can be found in the Texas A. &M. Research Foundation Report ( 1961). Inorganic phosphate concentrations were determined colorimetrically following the ammonium molybdate-stannous chloride method. Hydrological Results The monthly averages of each of the physico-chemical parameters in the three sub­areas are given in Figs. 2-6. For more details on the hydrological results, see "Hydro­logical and Biological Studies of the Mississippi River-Gulf Outlet Project," Texas A. &M. Research Foundation U961). TEMPERATURE Monthly mean temperatures are given in Fig. 2. A minimum of 5.2°C was present at SBB, sub-area 2, in February 1960 and a maximum of 34.9°C was found at RB, sub­area 1, in July 1960. The seasonal pattern is also very similar for each sub-area. The greatest increase in temperature occurred between March and April 1960 and the great­est decrease between November and December, in both 1959 and 1960. SALINITY Monthly salinities are given in Fig. 3. The average monthly salinity of sub-area 1 was 2.88 %o compared with 13.9 %o in sub-area 3_ Sub-area 2 had an intermediate rnlue of Sub area I --­ Sub area 2 --­ Sub area 3 --­ 6 4 0'--~A-H~~JJ~A'--~oJ-F~~H-A~~H'--J..__J.__~A~S~~O-N~~D,--J.,._~F,__-tr-_ -~s-'--~N-D~~ 1959 1960 1961 Fie. 2. Monthly average temperatures ( °C) for each sub-area. Sub -Orf!O I Sub-oreo 2 Sub-oreo 3 OL-.~A~iM~JL-~J~A.J.._~SL_~J,--~F__JM':--~A~M-!7--~Jo,--,tr-"*""--+~~196--,lb--' o~~N__JDL_~.,__~J~A+-~s!:---~ 1959 1960 FrG. 3. Monthly average salinity (%0 ) for each sub-area. 4.18%0• The lowest salinity, 0.53%0, occurred in sub-area 1 at station BD in April 1960. The highest salinity, 25.43 %0, was recorded in July 1960 at station LFF in sub· area 3. In sub-areas 2 and 3 salinities were at their minima in March and were con­sistently low in April and May. In sub-area 3 two notable salinity peaks were present, one during June-July 1960 and the other during December-January 1960-61. There were seasonal variations in salinity from one year to the next (Fig. 3) . TURBIDITY Turbidity values are given m Fig. 4. The maximum turbidity, 0.77 g/L, was re­corded at RB, sub-area 1, in February 1960. The minimum turbidity, 0.02 g/L, was recorded in several stations during the summer. High values were generally found from January through April, while the low values were recorded during the early summer and fall. Sub-area 1 had the greatest average turbidity and greatest seasonal variation of all the three sub-areas, followed by sub-areas 2 and 3. Variations of the turbidity in sub-area 3 seem independent of the variations in the other two sub-areas. OXYGEN Monthly dissolved oxygen averages are given in Fig. 5. A minimum oxygen value, 0.12 ml/L, was found at Station BD, sub-area 1, in September 1960. A maximum oxygen value, 7.41 ml/L, was found at Station BB, sub-area 2, in February 1961. Average monthly values were about 4.00 ml/L in all three sub-areas. During this investigation the highest oxygen values were found during the coldest months, that is, from December Zooplankton in the Salt Marshes of Southeastern Louisiana ,40 T J 1959 1960 1961 Frc. 4. i\Ionthly average turbidity (g/L) for each sub-area. ml T Frc. 5. J\Ionthly average oxygen ( ml/L) for each sub-area. 1959 to February 1960. The lowest values were encountered in the summer between June and August 1960 (see Fig. 5). INORGANIC PHOSPHATE Monthly inorganic phosphate concentrations are given in Fig. 6. The lowest phosphate value was 0.04 µ,g-at./L at station SBB, sub-area 2, in October 1960. The highest value, 8.24 µ,g-at./L, was at station BD, sub-area 1, in March 1961. Average values decreased from 2.11 µ,g-at. / L in sub-area 1 to 0.21 µ,g-at. / L in sub-area 3. The seasonal range was greater in sub-area l; the other two sub-areas showed only minor variations (Fig. 6). Results of Zooplankton Studies COMPOSITION OF THE ZooPLANKTON The zooplankton in the project area was mainly dominated by the following copepods : Acartia wnsa, Eurytemora hirundoides, and Oithona spp. Of these, A. tonsa was the most ubiquitous and most common. Others are listed in Table 1. Following is a list of taxa identified in the zooplankton collections : Foraminifera, medusae, Mnemiopsis sp., Beroe sp., Tomopteris sp., leeches, Acarina, Acartia wnsa, Centropages hamatus, Eury­temora hirundoides, Labidocera aestiva, Paracalanus crassirostris, Pseudodiaptomus coronatus, Tortanus setacaudatus, copepod nauplii, harpacticoids, Eucyclops agilis, Cyclops panamensis, Cyclops vernalis, Macrocyclops albidus, Oithona spp., Ergasilus sp., Cladocera, ostracods, Argulus sp., Cirripedia nauplii, Cirripedia cyprids, mysids, isopods, gammarids, shrimp larvae, zoeae, megalops, small crabs, snail veligers, cypho­naute larvae, echinoplutei, Oikopleura dioica, anchovy, croakers, gulf killifish, menhaden, silverside, striped mullet, worm eel, fish larvae and fish eggs. The name E. hirundoides was retained in this investigation to facilitate the com­parison with earlier studies. This copepod has been named E. hirundoides and E. a/finis. Sub-or ao I Sub-or~o 2 --------­ Sub-or~o 3 ---­ I' /"°', ./' ...... ,,,..,,.. ................. -----.... , ........ -----... _ / ' /.// ;--........_ -_____,,,_ ,,,,....-----.. _,,,. ........ ,,...----~~-, ............ ~:-..,,.. _/, ............... ~ ,_____ ,, --..... ... ._/ ~---.....----:~/-­ ----,,,..,,,. A M JJ A SO NDJFNAN J JAS O N DJ FN /959 1960 1961 FIG. 6. Monthly arnrage inorganic phosphate (µg-at./L) for each sub-area. Zooplankton in the Salt Marshes of Southeastern Louisiana Wilson (1959) believes that "most American records" of E. hirundoides were in fact records of E. affinis. Some of the morphological characteristics suggest one copepod to be Oithona similis. However, no positive species identification was obtained. DISTRIBUTION OF THE ZooPLANKTON Certain characteristic associations were found in each of the three sub-areas. Sub­areas 1 and 2 were characterized by the presence of fresh or brackish water organisms, such as water mites (Acarina), parasitic forms (Argulus sp., Ergasilus sp.), or copepods (Eurythemora hirundoides). Sub-area 3 possessed representatives of the coastal marine waters, such as the copepods: Centropages hamatus, Labidocera aestiva, Paracalanus crassirostris, Pseudodiaptomus coronatus, Tortanus setacaudatus and Oithona sp., and other invertebrates such as medusae, ctenophora, echinoplutei, cyphonaute larvae, mol­luscan larvae, pelecypod larvae, and Oikopleura dwca. The fauna common to all areas studied included: (a) holoplankton such as the copepod Acartia tonsa which can survive and live within extremes of salinity; (b) mero­plankton such as crab zoeae, shrimp and fish larvae which migrate from the salt water to the more protected brackish areas where there is an abundant food supply. The relative abundance of zooplankton for each station in the three sub-areas is given in Table 1. This table shows that sub-area 1 had the largest population followed by sub· areas 2 and 3 respectively. This was primarily caused by the preponderance of Acartia tonsa in sub-area 1. Fig. 7 shows that Acartia tonsa not only was present everywhere at all times during this investigation, but was the principal component of the zooplankton: Acartia was nearly twenty-five times more abundant than Eurytemora hirundoides, the second copepod in numerical abundance. Table 1 shows that sub-area 1 had the largest numbers of plankton organisms followed closely by sub-area 2, while sub-area 3 had only a little more than half the population of sub-area 1 or 2. There is a general decrease in number of A . tonsa from Lake Borgne stations to the stations within the bayous, that is from LB and BDL in sub-area 1 and SBB and BML in sub-area 2. In sub-area 3, except for station LAS where the plankton catches were invariably inferior to those of other sta­tions, there was less than a 10 per cent difference among the catches of the four remain­ing stations. Eurytemora hirundoides occurred in great abundance in sub-area 1, especially in Lake Borgne stations. In sub-area 2 the Eurytemora population was only one-fourth of that in sub-area 1. E. hirundoides was never recorded from sub-area 3. On the other hand Oithona sp. was found more frequently and in greater abundance in sub-area 3 than in the other two sub-areas. The latter sub-areas had approximately the same size population. Copepod nauplii were found in greatest numbers in sub-areas 1 and 2. Their popula­ tion density in sub-area 3 was only one-third of that of the nauplii of sub-area 2. Cirripedia nauplii in sub-area 1 were found in numbers almost equal to those in sub-area 2. On the other hand, sub-area 3 had nearly ten times as many as either one of the other areas. Crab zoeae were more abundant in sub-area 3 but the differences among the three sub-areas were small. TABLE 1 Catch per 5-minute haul of representative plankters in all three sub­areas• BD Sub-Area 1 BDB RE BDL LE SBB Suh-Area 2 BML JDY BG BM BPPN LAN Sub-Area 3 LAS LMN LFF Nl c .g i:i" "" ~ 8' Total samples per station: 41 34 39 42 28 Total 19 40 40 41 41 Total 35 35 31 35 26 Total "" ~­ Organisms: Acartia tonsa Eurytemora hirundoides 163 5 103 6 94 11 209 15 412 48 981 85 465 9 274 7 60 1 50 2 38 2 887 21 111 109 64 93 92 469 s.. ~ CJ) ~ ~ Paracalamus crassirostris Pseudodiaptomus coronatus Harpacticoids 1 x 1 x 2 x x x x x x xt x x x x 1 x 3 x 7 24 x JO 27 x ~ ~ .... "'~ ~ "' ~ Cyclopoids 9 2 15 7 1 34 x x x x x x x x x x x x CJ) c Ergasilus sp. Oithona spp. Copepod nauplii Cirripedia nauplii x 1 21 x x 4 2 x x 12 x x 8 x 1 28 2 x 2 73 7 x x 18 2 x x 9 1 x x 6 1 x x 9 x x 6 1 x x 48 6 x 8 11 x 6 5 3 15 11 6 12 2 6 40 16 9 x Bl 35 35 ~ s.. ~ ~ "'I;..., "" r.... c Zoeae 2 3 x 7 1 2 1 1 6 4 1 1 2 2 JO ~.... "' Fish larvaet 123 42 21 171 155 512 71 21 15 9 3 119 6 10 24 12 9 61 ~­"" ~ • All figures represent the mean in thousands per station. t x indicates that the mean number was less than 1000. Dashes indiral~ thal no spe<".imens were found in tht~ aliquots cxumim•tl nt that pnrlir.ulnr stalion. Fil(lirt•s given for the fish larvae rt~prescnt the total numbers per slntion. ~ ...... •A. tonsa ofllBr copBpods nauplii CirripBdia nauplii • Zo8a8 I 5 2 x 10Orqonisms "') (\j ""' ""' " .... ~ ~ ~ I I '5 ~ V) I V) I I ~:::::: ·.·...· I .·:.::· Frc. 7. Total numbers of the main plankters in all three sub-areas. SEASONAL DISTRIBUTION OF THE ZOOPLANKTON Seasonal patterns of distribution are given in Figures 8-14 showing that all three sub-areas exhibited marked seasonal changes in the species composition as well as in the number of zooplankton organisms per volume. All numbers are given as monthly aver· ages. Thus, when 3 hauls were made at one station during one month the three results were added up then divided by 3, etc. A well-defined population explosion was observed in April 1960 which coincided with the tremendous increase of Acartia tonsa during that month (see Fig. 8). Minor peaks were also noticed in the early fall of 1960. The peaks in 1959 were much smaller than in 1960 and occurred during October in sub·area 2, during November in sub-area 3, and during December in sub-area 1. Eurytemora hirundoides was caught between November and July with a seasonal maximum in April in sub-areas 1 and 2 (see Fig. 9). The seasonal maximum of Oithona spp. also occurred in April in sub-area 3, but a secondary peak in the fall of 1959 was I 1959 1960 1961 I Sub-area I --­SUb-area 2 --­ ~ () " I! '-50 000 .," ~ I! ., ·~ " ~ () ~ () ... i2S " ~ " " ~ so 000 JASONO J JASON OJFN 19S9 1960 1961 F1G. 9. :\Ionthly distribution of Eurytemora hirundoides in sub-areas 1 and 2. J ASONOJFMAM J JASONDJ FM 19S9 1960 1961 FIG. 10. Monthly distribution of the copepod nauplii in sub-areas 1, 2, and 3. not repeated in 1960. Oithona spp. was present between April and December, but disappeared during the colder months until the next cycle. Copepod nauplii were present at all times during the year with their highest numbers occurring in April 1960 (see Fig. 10). In 1959 there was an increase in number in the fall, to which there was no counterpart in 1960. ~ ~ ... ~ " .. I! -!2 " " ~ () so Sub-or~a I Sub-area 2 Sub-ort10 3 0 00 ,1 I\ f I I I f \ I /\ I I I \1 I I Zooplankton in the Salt Marshes of Southeastern Louisiana Figures 11 and 12 show that the Cirripedia nauplii and cyprids had spring maxima in sub-areas 1 and 2 from May to June 1960 with minor peaks in August. On the other hand, in sub-area 3 the spring maxima occurred in April. The distribution of the cyprids was related closely to that of the nauplii although their numerical increase in April was small, as shown in Fig. 12. Data on the distribution of zoeae in 1959 are incomplete (Fig. 13). Possibly there was a seasonal peak ending in July in sub-areas 1 and 2. Not enough information was available from sub-area 3 to infer any trend. The following year, sub-area 1 had two peaks, one in April and the other in September. In sub-area 2 the April maximum was followed by another maximum in August. In sub-area 3 the greatest numbers were found in September with two other periods of abundance, in May and July. No zoeae were caught after October, either in 1959 or 1960 (see Fig. 13). Only a few megalops were present in the samples ; all were taken in July. Fish larvae were present the first six months of the year, but after June they were caught only occasionally. Ergasilus sp. had its main period of abundance in late spring or early summer. The Cladocera were scattered throughout the whole year without any well-defined seasonal maximum. No seasonal variation was evidenced in the distribution of the ostracods. Gammarid amphipods were slightly more numerous during the colder months. Mysids were not present in the catches between March and August. The water mites (order Acarina) were collected intermittently throughout the survey. Leeches were found only on two occasions in December and February. Centropages hamatus appeared only in December 1960. Sub-or~o I --­Sub-or~ 2 -----­ ~' Sub-or~o 3 --­ I\ 150, i \ \ I I ~ c \ "' I I "' :;;100000 I I "­ " ~ " " I "' I I c I I \ I I I ' ' \ ' FIG. 11. Monthly distribution of the Cirripedia nauplii in sub-areas 1, 2, and 3. Zooplankton in the Salt Marshes of Southeastern Louisiana Sub-oreo 3---­ -<:: .... c: () e; ... 'll q_5o 0 0) e; .".J c: () ~ () ... "' 'll %25, 000 c: 1959 J A S 0 N 0 J F M A M J J A S 0 N 0 1960 Fie. 12. Monthly distribution of the Cirripedia cyprids in sub-area 3. Labidocera aestiva was found once in April 1960 and was present in September and October 1960. Paracalanus crassirostris appeared in April and May. Pseudodiaptomus coronatus had spring and fall maxima with reduced numbers m between. Tortanus setacaudatus was present in the summer and fall of 1959 and 1960. It was sparsely distributed throughout the rest of the year. The ctenophore, Mnemiopsis sp., was more abundant than Beroe sp. The latter was present mainly in the summer while the former was found frequently in winter and spring but was scarce or absent in the warmer months. Medusae were recorded in winter and spring. Echinoplutei were present during the summer and early fall months with a distinct peak in August. Cyphonaute larvae were present in the fall of 1959 and in the spring of 1960. The pelecypod larvae, although too small to be retained effectively by the net, were found in large numbers in April at LFF, sub-area 3. Almost all the specimens were collected in spring or early summer. Oikopleura dioica had a small peak in April and was present through October. FIG. 14. Abundance of fish larvae and Acartia tonsa in the project area. Harpacticoids followed the trend of the majority of the plankters by having their yearly peak in April. Similarly, the cyclopoids were significant only in April and May although they never represented more than a small fraction of the copepods. Sull -ar•a I Sull -ar•a 2 ------­Sull-artta .J ---­ ~ " sci e; " '­ ~ ~ .!! .. " " '­ " .... 00 " 25 '­ " "' ~ ~ ~ 5, 000 J A 1959 SONOJFHA N 0 J F H 1980 1981 FIG. 13. Monthly distribution of zoeae in sub-areas 1, 2, and 3. Zooplankton in the Salt Marshes of Southeastern Louisiana The polychaete larvae reached a peak in April-May and in October-November of 1959 and 1960. The isopods were present occasionally throughout the survey in all three sub-areas, mainly in the bayous. The shrimp larvae were caught more often in April, but were absent from November to March. Discussion of Hydrological Conditions TEMPERATURE On the average there was very little temperature difference among the three sub-areas. Even during the coldest months, December, January, and February, or when the tem­peratures were at their highest in July and August, A. tonsa was present in large numbers (Fig. 8). However, E. hirundoides was absent from the hauls during the summer months. Although the temperature differences from one year to the next were only minor, there was a significant difference in the size of the plankton population during the two years. SALINITY The planktonic fauna reflected the salinity conditions in the project area. Some of the plankters were of either marine or fresh water origin. The majority, however, were typical of brackish conditions. Numerically the marine and fresh water forms were of little importance; both were transient. Lake Pontchartrain, connected to the project area by a narrow passage, the Rigolets, also is submitted to the same influences. Darnell (1962) noted that during periods of high salinity a large element of typically marine forms entered the lake. During periods of low salinities, fresh water species appeared in some numbers. The rest of the time a graded species spectrum was present. Some of the Cladocera, Ostracoda or cyclopoid copepods which were found in greatest concentration at station BD-the lowest salinity station of sub-area I-were encountered also occasionally at the adjacent stations in sub-area 1 and sometimes in sub-area 2. On the other hand, medusae and ctenophores were rarely found outside sub-area 3. Whereas in the fall of 1959 the collections showed the presence of typically marine forms in sub­area 3, this phenomenon was absent in 1960. The variation in salinity .may be the result of several factors, including winds driving Gulf water in and out of the marshes, and fresh water discharge from the Pearl River. An increase in salinity sometimes brought typically marine organisms into the project area, especially in sub-area 3, including Oithona sp., P. crassiorostris, P. coronatus, T. seta­caudatus and medusae. The discharge of fresh water into the project area may have dispersed part of the autochthonous plankton population outside the sampling area possibly through Bayou Y closkey, Bayou La Loutre and Bakers Canal, all of which were located outside the bio­logical sampling zone. It is less likely that the currents carried the fauna through Bayou St. Malo, since there was little water exchange between Lake Borne and this bayou system (Texas A. &M. Research Foundation, 1961). TURBIDITY High turbidity values and high phosphates were found concomitantly in sub-areas 1 and 2. In both cases there was a decrease in values as salinity increased. Stations of sub· area 2 exhibited very little variation among themselves. Sub-area 3 had lower turbidity values than either of the other sub-areas suggesting the influence of the salt water in reducing turbidity values through flocculation and precipitation. No correlation was found between the number of copepods and the turbidity value. It is not impossible, however, that some copepods utilized the suspensoids as a food source (Darnell, 1961). Early fish stages may also find a food source in this suspended detrital material. Darnell (1958) considered the post-larval stages of fish as general scavengers. The greatest num· her of juvenile fish were encountered in sub-area 1. A similar explanation may account for the zoeae which were also more abundant in the same sub-area. OXYGEN All the averages of oxygen showed high values, more than 50 per cent saturation. INORGANIC PHOSPHATE The higher inorganic phosphate found in the bayous of sub-area 1 may be attributed to sewage contamination in the upper reaches of Bayou Bienvenue. Higher nutrient levels in this area may also be indicated by the population levels there. Discussion of Populations Acartia tonsa Conover (1956) suggested that A. tonsa might attain an important position in the plankton community only when salinity restricted the presence of other copepods. Davis (1944) reported A. tonsa as the dominant copepod of Chesapeake Bay. Later Davis (1950) mentioned again A. tonsa as the most abundant of the copepods sampled in the brackish waters of southern Florida. Conover (1956) found A. tonsa in conjunction with A. clausi in Long Island Sound. A. tonsa was dominant only in the summer with a peak in August. In the Laguna Madre, A. tonsa was the major copepod, found in salinities ranging from 8 to 75 %0 , and was most abundant between 47 and 75 %o (Simmons, 1957). Similar findings were reported by Breuer (1957) in Baffin and Alazan bays where A. tonsa dominated the zooplankton populations also and accounted for large plankton volumes. The salinities in these two bays varied from 1 to 75 %0 • Fleminger (1956) in his survey of the calanoid copepods of the Gulf of Mexico found A. tonsa almost ex· elusively in those regions "where considerable amounts of land drainage water flow." Additional evidence shows that they are more successful in low salinities and land-locked bodies of waters than in competition with other copepods in the open ocean. Deevey (1948) recorded A. tonsa as the main species in the summer in Tisbury Great Pond. Deevey (1952 a, b) again described the important role of A. tonsa during the summer in Block Island Sound both from 1943 to 1946 and in 1949. In the surface waters of the Delaware Bay region, Deevey mentioned A. tonsa as the most important year-round Zooplankton in the Salt Marshes of Southeastern Louisiana copepod species of the bay. At Great Pond, Falmouth, Massachusetts, Barlow (1952) found a greater concentration of A. tonsa in the Pond than in the outside waters of Vine­yard Sound. In Alligator Harbor, A. tonsa was the second most numerous copepod throughout the year (Grice, 1956). In the Chicken Key area, A. tonsa constituted 60 per cent of population (Woodmansee, 1958). Off the Mississippi River mouth, Gonzalez (1958) recorded a spring maximum and conspicuous concentrations of A. tonsa in the winter. The environment itself does not seem to be a limiting factor in the proliferation of A. tonsa, but when the environment becomes less forbidding to other species, the com­petitors outgrow A. tonsa. Deevey (1948) noted that the disappearance of A. tonsa coin­cided with the arrival of large populations of A. clausi and E. hirundoides. Coker and Gonzalez (1960) found large numbers of A. tonsa only where species diversity was minimal and in the vicinity of Bahia Fosforente in Puerto Rico; few were found other­wise. In Lake Ponchartrain, Darnell ( 1961) found the greatest abundance of copepods (of which A. tonsa was the major representative) , at the surface in areas "characterized by mixing of water masses, bottom roiling, and proximity to eroding marshes." This de· scription may be used to summarize the findings of this survey also. Eurytemora hirundoides E. hirundoides is a brackish water copepod with a preference for the less saline parts of its environment. Foster ( 1904) had recorded the species from the fresh and brackish waters of New Orleans and Calcasieu Pass in the Mississippi delta. Wilson ( 1932 a) mentioned E. hirundoides as one of the inner bay species in Chesapeake Bay. In Tisbury Great Pond it was present from November until July with a peak in March (Deevey, 1948); in Delaware Bay it was present only from March until May (Deevey, 1960). All these results are comparable to the findings of this investigation. Between July and No­vember E. hirundoides did not occur in the plankton samples. The numbers in the Lake Borgne stations of sub-areas 1 and 2 were greater than in the bayou stations of these same sub-areas demonstrating the great similarity of distribution of A. tonsa and E. hirun­doides with respect to the land masses. Deevey (1960) indicated that E. hirundoides was eurythermal and euryhaline and occurred in waters ranging from 0 to 24°C and salinities of 1 to 31 %0 • CoPEPOD NAUPLII Stations SBB and LB, sub-area 1, had the largest copepod populations during this in­vestigation and also had the largest nauplii populations. In sub-area 3 the number of nauplii increased in a seaward direction suggesting the marine origin of the adults. Since the #6 net does not sample these early copepod stages adequately, a considerable source of error was introduced thereby. Even the sixth and last stage of the A. tonsa nauplii was smaller than 0.239 mm (Conover, 1956). This biased sampling applied to forms smaller than 0.239 mm in their smallest dimension. If the net were 100 per cent efficient, theoretically they would not be caught at all. During this investigation a certain ratio was maintained in all three sub-areas between the total number of copepods and copepodites and the total number of nauplii. The ratios were 2.75:1, 3.02:1, and 2.88:1, for sub-areas 1, 2 and 3 respectively. In other words, there was a direct relationship between the number of nauplii and the number of Zooplankton in the Salt Marshes of Southeastern Louisiana adults or near adults. This distribution did not hold on a month-to-month basis, how­ever. Peak numbers of copepods and copepodites were not followed by a comparable increase in the number of nauplii. NAUPLII AND CYPRIDS OF BARNACLES Although the distribution of the adults was undefined, it is reasonable to assume that the cirripeds are more numerous in sub-area 3 since both nauplii and cyprids were found in that sub-area in greater numbers. ZOEAE Observations on the distribution of the crab zoeae tend to support some of the hypothe­ses advanced by Darnell (1959). Darnell had noted that in spite of the frequent appear­c;tnces of benthic forms in the surface plankton of Lake Pontchartrain, few crab larvae were present. He then concluded that CaUinectes sapidus spawned nearby in Lake Borgne or in Chandeleur Sound. Ovigerous females were absent from Lake Pontchar­train in February or March and again in August and September. Although the counting procedures did not prove that zoeae caught in the project area were exclusively blue crab zoeae, it is very likely that the abundance of the adult blue crabs (Texas A &M Research Foundation, 1961) is reflected in the abundance of the larval stages in the samples. In sub-areas 1 and 2 which are closely related to Lake Pontchartrain through the Rigolets and Chef Me~teur the crab zoeae were found in greater abundance both in April and in August-September. FISH LARVAE The fish larvae and post-larvae remained largely unidentified. It is believed, how­ever, that the majority belonged to the genus Anchoa sp. Sub-area l, which had the greatest number of copepods, also had the greatest number of fish larvae. In sub-area 2 the number of fish larvae had dwindled to one-fourth that of sub-area 1 and in sub-area 3 it was only one-eighth that of sub-area 1. On a station-to-station basis the same type of distribution is evident: The stations yielding the greatest numbers of copepods also had the greatest number of fish larvae (see Fig. 14). In sub-area 3 where all the stations had numerically similar catches of copepods on the average, the fish were numerically low and varied only slightly from station to station. It may be significant, however, that the spot, Lewstomus xanthurus; the anchovy, Anchoa sp. (probably A. mitchilli diaphana); and the Atlantic croaker, Micropogon undulatus, that constituted together 70 per cent of all the fish caught in the project area during this study, are also reported to be plankton feeders in the early stages of their life cycle (Darnell, 1961) . The adults are less important in the economy of the plankton, since they usually eat bottom invertebrates or larger organisms. The adult anchovies, however, still rely on copepods as part of their food (Darnell, 1958) . Although there was no direct evidence, it is possible that the concentration of fish larvae at some of the stations may have resulted from the concentration of zooplankton at the same location. Zooplankton in the Salt Marshes of Southeastern Louisiana MINOR COMPONENTS The minor components of the plankton may be discussed in three groups. Group 1 plankters were typical of low salinity waters of sub-areas 1 and 2 and may have had a fresh water origin. These included the parasitic branchiuran genus Argulus, a species of the parasitic copepod genus Ergasilus, and Cladocera of the family Chy­doridae from Bayou Dupre of sub-area 1. Group 2 plankters were those typically marine organisms taken in sub-area 3, es­pecially Centropages hamatus, Labidocera aestiva, Paracalanus crassirostris, Pseudo­diaptomis coronatus, and Tortanus setacaudatus. Centropages hamatus is a surface cope­pod with a wide temperature range. Deevey (1960) found it inside and outside the bays, with greater numbers in the open waters, occurring generally in the winter in warm waters. Labidocera aestiva was one of the largest copepods encountered during the investiga­tion. However, it did not form a very significant part of the copepod population. Wilson (1932a) noted that the presence of L. aestiva in Chesapeake Bay was only occasional while it was always present in the outside waters, often near the bottom. Grice (1956) suggested that L. aestiva reproduced in the waters outside Alligator Harbor. Gonzalez (1958) described L. aestiva as "fairly common throughout the year" off the mouth of the Mississippi River. L. aestiva was found in relatively large numbers in late' summer, but migrated outside the bay shortly thereafter. Paracalanus crassirostris increased in numbers in those stations under the influence of Breton Sound, suggesting that origin. In Great Pond, Falmouth, Barlow (1952) reported P. crassirostris in small numbers compared to the outside waters of Vineyard Sound. Gonzalez (1958) recorded increasing numbers of P. crassirostris sampling from a bay with restricted access to the offshore waters. Pseudodiaptomus coronatus was reported by Wilson (1932) as a brackish-water spe­cies. Gonzalez (1958) encountered specimens at one station close to the Mississippi outflow. Fleminger ( 1956) found P. coronatus associated with A. tonsa and L. aestiva in the regions most subjected to land drainage. According to Grice ( 1956), P. coronatus inhabits the deeper waters during the daylight hours and migrates diurnally. In Alli­gator Harbor most of the specimens were caught in the evening. This might support the view that they live close to the bottom or burrow during the day. Deevey's (1960) con­clusions were almost identical. There was evidence that the "female prefers deep water" and "possibly the major part of the P. coronatus population remained well below the surface." This survey is apparently the first to report a significant number of Tortanus seta­caudatus in the Gulf of Mexico region. Foster ( 1904) has a record of unidentified species of Tortanus taken near the Gulf Biological Station which might well be T. setacaudatus. Fleminger (1956) caught T. setacaudatus in only one sample at the entrance of Galveston Harbor. In general, the samples with ctenophores or coelenterates contained fewer copepods than the others (Reid, 1955; Cuzon du Rest, 1959). Barlow (1952) has observed in Great Pond that the decrease in zooplankton population coincided both in 1950 and 1951 with the appearance of ctenophores. The number of A. tonsa rose sharply at all the stations of sub-area 3 both in the fall of 1959 and 1960 after the ctenophores had a seasonal decline. Two hypotheses are suggested: ( 1) either the ctenophores clog up the net and reduce its filtering capacity (Davis, 1948); or (2) there is a biological inter­action responsible for decrease in the zooplankton population (Deevey, 1960). The majority of the echinoplutei was found near LAS, sub-area 3, suggesting that this sub-area might be used for breeding grounds. Oikopleura dioica constituted only a small share of the plankton population. Group 3 plankters were common to all three sub-areas. Harpacticoids were repre­ sented in all three sub-areas but were more numerous in sub-area 1. The Lake Borgne stations which had the largeEt numbers of A. tonsa and E. hirundoides had few or no harpacticoids. Four species of cyclopoids were identified: (1) Cyclops panamensis; (2) Cyclops vernalis; (3) Eucyclops agilis; and ( 4) M acrocyclops albidus. The first two species were the most abundant. The cyclopoids were over sixteen times more numerous in sub-area 1, especially at RB and BD, than in sub-area 3. Sub-area 2 had the smallest numbers. The cyclopoids found in this investigation are reputed to be brackish-water forms (Yeatman in Ward and Whipple, 1959). The number of polychaete larvae did not vary noticeably from one sub-area to the next nor from one station to another. The Lake Borgne stations, however, had smaller numbers than any other stations and fewer were caught in sub-area 1 than in the other two sub-areas. Although shrimp larvae were ubiquitous, their highest numbers occurred in the high salinity stations close to Breton Sound. Planktonic gastropods were too small to be adequately sampled by a #6 net. Speci­mens taken showed an increase in their population from sub-area 1 to sub-area 3. Acknowledgments The writer is obliged to Dr. Dale Leipper, Head of the Department of Oceanography and Meteorology for providing the necessary facilities and to Dr. K. M. Rae who sug­gested and planned this investigation. Drs. Harry C. Yeatman and George D. Grice assisted in the identification of the copepods. Messrs. Dean Letzring, Cornelius Mock, and Warren Mones made many of the plankton collections. Grateful appreciation is ex­pressed to Mrs. Anne Wilkey and the author's wife who provided editorial assistance. Literature Cited Barlow, John P. 1952. Maintenance and dispersal of the endemic zooplankton population of a tidal estuary, Great Pond, Falmouth, Massachusetts. Ph.D. Thesis. Harvard University, Cambridge. Breuer, Joseph P. 1957. An ecological survey of Baffin and Alazan Bays, Texas. Puhl. Inst. Mar. Sci. Univ. Tex. 4(2): 134-155. Biickmann, A. 1945. Appendicularia I-III Fiches d'identification du zooplankton, sheet 7. Conseil Permanent International pour !'Exploration de la Mer. Fred Andr. Hpst et Fils, Copenhagen. 8 p. Coker, Robert E., and Juan G. Gonzale'. 1960. Limnetic copepod populations of Bahia Fosforente and adjacent waters, Puerto Rico. J. Elisha Mitchell sci. Soc. 76(1) : 8-28. Conover, Robert J. 1956. Oceanography of Long Island Sound 1952-54. IV. Biology of Acartia clausi and A. tonsa. Bull. Bingham oceanogr. Coll. 15 : 156-233. Cuzon du Rest, R. P. 1959. Plankton distribution in the Southern Puget Sound. University of Wash­ington, Seattle, Unpublished manuscript. 105 p. Darnell, Rezneat M. 1958. Food habits of fishes and larger invertebrates of Lake Pontchartrain, Louisiana, an estuarine community. Pub!. Inst. Mar. Sci. Univ. Tex. 5: 353-416. Darnell, Rezneat M. 1959. Studies on the life history of the blue crab (Callinectes sapidus Rathbun) in Louisiana waters. Trans. Amer. Fish. Soc. 88(4): 294-304. Zooplankton in the Salt Marshes of Southeastern Louisiana Darnell, Rezneat M. 1961. Trophic spectrum of an estuarine community, based on studies of Lake Pontchartrain, Louisiana. Ecology 42(3): 553-568. Darnell, Rezneat M. 1962. Ecological history of Lake Pontchartrain an estuarine community. Amer. Midi. Nat. 68 (2) : 434--445. ' Davis, Charles C. 1944. On four species of copepods new to Chespeake Bay with a description of a new variety of P. crassirostris Dahl. Biol. Lab. Puhl. Dept. Res. Ed. Md. Ches. 61: 1-11. Davis, Charles C. 1944. Notes on the plankton of Long Lake, Dade County, Florida, with a descrip­tion of two new copepods. Quart. J. Fla. Acad. Sci. 10(203): 78-88. Davis, Charles C. 1950. Brackish water plankton of mangrove areas in Southern Florida. Ecology 31 ( 4) : 519-531. Deevey, Georgiana B. 1948. The zooplankton of Tisbury Great Pond. Bull. Bingham Oceanogr. Coll. 12(1): 1-44. Deevey, Georgiana B. 1952a. A survey of the zooplankton of Block Island Sound 1943-46. Bull. Bing­ham Oceanogr. Coll. 13(3): 65-119. Deevey, Georgiana B. 1952b. Quantity and composition of the zooplankton of Block Island Sound 1949. Bull. Bingham Oceanogr. Coll. 13(3): 120-164. Deevey, Georgiana B. 1960. The zooplankton of the surface waters of the Delaware Bay region. Bull. Bingham Oceanogr. Coll. 17(2) : 5-53. Farran, G. P. 1948. Copepods, Fiches d'identification du zooplankton sheet 12, Conseil Permanent International pour J'Exploration de la Mer. Fred H~st et Fils, Copenhagen. 4 p. Fleminger, A. 1956. Taxonomic and distributional studies of the epiplanktonic calanoid copepods (Crustacea) of the Gulf of Mexico. Unpublished Ph.D. Thesis. Harvard University, Cambridge. Foster, E. 1904. Notes on the free-swimming copepods of the waters in the vicinity of the Gulf Bio­logical Station, Louisiana; second report. Gulf Biol. St. Bull. 2: 69-79. Gonzalez, Juan G. 1958. The distribution of copepods in the Mississippi delta region, in A study of some factors involved in the disposal of radioactive wastes at sea, Part III. Texas A & M Re­search Foundation. Grice, George D. 1956. A qualitative and quantitative seasonal study of the Copepoda of Alligator Harbor. Pap. oceanogr. Inst. Fla. Univ. 2: 37-76. Gunter, Gordon. 1952. Historical changes in the Mississippi River and the adjacent marine environ­ment. Puhl. Inst. Mar. Sci. Univ. Tex. 2(2): 119-139. Meehan, 0. Lloyd. 1940. A review of the parasitic crustacea of the genus Argulus. Proc. U. S. nat. Mus. 88: 459-522. O'Neal, Ted. 1949. The Muskrat in the Louisiana coastal marshes. Louisiana Department of Wild­life and Fisheries, New Orleans. 152 p. Penfound, W. T., and E. S. Hathaway. 1938. Plant communities in the marshland of southeastern Louisiana. Ecol. Monogr. 8: 1-56. Pennak, Robert W. 1953. Fresh water invertebrates of the United States. The Ronald Press Co., New York. 769 p. Pratt, Henry S. 1935. A manual of the common invertebrate animals. P. Blackiston & Son Co., Inc., Philadelphia. 834 p. Reid, George K., Jr. 1955. A summary study of the biology and ecology of East Bay, Texas. Tex. J. Sci. 8(3): 316--343. Rose, M. 1933. Copepods pelagiques. Faune de France 26: 1-374. Russell, R. J. 1936. Physiography of the lower Mississippi Delta. La. Dept. of Conservation, Geol. Bull. 8: 3-199. Sars, G. 0. 1903. An account of the crustacea of Norway, Copepoda Calanoida. Bergen Mus., Bergen, 4: 1-171, 108 plates. Sars, G. 0 . 1918. An account of the crustacea of Norway, Copepoda Clyclopoida. Bergen Mus., Bergen, 6: 1-223, 118 plates. S:mmons, Ernest G. 1957. An ecological survey of the upper Laguna Madre of Texas. Pub!. Inst. Mar. Sci. Univ. Tex. 4(2): 156-200. Smith, Roland F. 1949. Notes on Ergasilus parasites from New Brunswick, New Jersey area with a checklist of all species-hosts east of the Mississippi River. Zoologica 34: 127-182. Texas A & M Research Foundation. 1961. Hydrological and Biological Studies of the Mississippi River-Gulf Outlet Project. 217 p. Treadwell, Robert C. 1955. Trafficability and navigability of delta-type coasts-Louisiana coastal marshes. Louisiana State University, Baton Rouge. Technical Report No. 6. Sedimentology and Ecology of Southeast coastal Louisiana. 1-77. Ward and Whipple. Second edition, W. T. Edmondson. 1959. Fresh water biology. John Wiley and Sons, Inc., New York. 1248 p. Wilson, Charles B. 1932a. The copepod crustaceans of Chesapeake Bay. Proc. U. S. nat. Mus. 80(15): 1-54. Wilson, Charles B. 1932b. The copepods of the Woods Hole region, Massachusetts. Bull. U. S. nat. Mus. 158: 1--635. Wilson, Mildred S. 1958. The copepod genus Ilalicyclops in North America with a description of a new species from Lake Pontchartrain, Louisiana and the Texas coast. Tulane Stud. Zoo!. 6(4) : 176-189. Wilson, Mildred S. 1959. Branchiura and parasitic copepods. p. 862-868. In Ward and Whipple. Second Edition, W. T. Edmondson. Fresh Water Biology. John Wiley & Sons, Inc., New York. Woodmansee, Robert A. 1958. The seasonal distribution of the zooplankton off Chicken Key in Biscayne Bay, Florida. Ecology 39(2) : 247-262. Oxygen Metabolism of Four Oklahoma Farm Ponds B. J. COPELAND Institute of Marine Science, University of Texas Port Aransas, Texas and w. R. WHITWORTH Aquatic Biology laboratory, Oklahoma State University Stillwater, Oklahoma Abstract Oxygen metabolism of four Oklahoma farm ponds was studied during the spring and summer of 1962. Gross photosynthetic productivity ranged between 4.4 and 27.4 gm 0 0 /m2 per day and total community respiration ranged between 6.4 and 26.4 gm O.,/m2 per day. These values are of the same magnitude or higher than those reported for similar unpolluted communities and only slightly less than those reported for polluted systems. Introduction Dotting the landscape of Oklahoma are numerous farm ponds of various sizes, mor­phologies and chemical characteristics. These ponds receive waters that have drained from rich and poor rangelands and farmlands. Relatively few studies have been made of the metabolism of this type of aquatic community. Most studies are on polluted streams and ponds, lakes, springs, and marine waters. Some of the best sports fishing in Oklahoma are found in farm ponds, yet few efforts have been made to appraise their primary productivity. To obtain some idea of the magnitude of photosynthesis and community respiration, free-water oxygen methods were applied to four farm ponds r.ear Stillwater, Oklahoma during the spring and summer of 1962. Methods The methods of Odum (1956) and Odum and Hoskin (1958) were followed to obtain the community metabolism. Depth of light penetration was determined with a submarine photometer, and was that depth at which light was 1 % of surface intensity. Oxygen content was measured in duplicate every three hours by the Alsterburg modification of the Winkler method (A.P.H.A., 1960). Rate of change curves were corrected for ex­change of oxygen between the water and the atmosphere as outlined by Odum (1956). To ascertain the presence of stratification in the ponds, oxygen measurements were made at three depths and three positions in each pond on two different occasions (May 1 and 6, 1963). Typical wind conditions existed at the time of the measurements, i.e., 15 to 20 miles per hour on May 1 and less than five miles per hour on May 6. Oxygen con­centration differed less than 0.5 mg/liter in Ponds 1, 3, and 4 for all samples, indicating little or no stratification. In Pond 2, however, oxygen concentration differed by as much as 2.5 mg/ liter from surface to bottom, indicating stratification. Therefore, community metabolism reported in the following discussion is indicative of only the euphotic zone (as measured by 1 % light penetration) for Pond 2 and is indicative of the whole pond in the unstratified ones. DESCRIPTION OF THE PONDS The four ponds, unnamed, so therefore, designated Ponds 1 through 4, were located in Payne County within one mile of Stillwater, Oklahoma. The ponds were chosen because they represent four of the common types found in the area. The ponds had a surface area of one-fourth acre (Ponds 1, 2, and 4) and one-half acre (Pond 3), and an average depth of one to two meters. Pond 1 was located below the feedlot of a swine barn and received the waste products of the swine as well as leftover feed. Consequently the pond community was very fertile and supported a dense growth of Spirogyra sp. However, light often penetrated to the bottom of the pond, especially when a break in the vegetation occurred. Pond 2, located about one-fourth mile east of Boomer Lake, drained about 40 acres of lush rangeland. The dominant vascular plant was Najas guadalupensis (naias). The planktonic algae were dominated by diatoms. The water was usually clear and the average measured depth of light penetration was about one to two meters. Pond 3, located near the eastern city limits of Stillwater, drained about 80 acres of overgrazed, seriously eroded pastureland. The water was turbid with colloidal clay particles and light rarely penetrated below 0.6 meters. The principle vascular plant was fussiaea repens (water-primrose) . The planktonic algae were dominated by diatoms. Pond 4, near highway 51 on the east side of Stillwater, received water from good grass cover and approximately one acre of chicken pens. The water was usually clear and light often penetrated to the bottom. The principal vascular plants were Sagittaria spp. (arrowheads) and N ajas guadalupensis ( naias). An extremely diverse and rich non­vascular flora was also present (attached and planktonic algae) . Oxygen Metabolism Typical diurnal oxygen curves were obtained during the summer. A representative curve for turbid waters is shown in Fig. 1 for Pond 3, a pond turbid with colloidal clay from the eroded drainage area. A heavy cloud cover existed for the entire diurnal period and undoubtedly suppressed photosynthesis. The water was undersaturated during most of the diurnal period. Photosynthesis was about two-thirds of the total respiration (P / R ratio of 0.7). A diurnal oxygen curve, representative of those obtained in Ponds 2 and 4 during summer, is presented in Fig. 2 for Pond 4 on August 18, 1962. The water was super­saturated during most of the daylight period. Photosynthesis was approximately the same as community respiration (P/ R ratio of about 1.0) . The agreement between repli­cate oxygen samples indicates continuous mixing. Fig. 3 shows a typical diurnal curve for Pond 1 during spring. Photosynthesis in­creased during the day to a maximum in late afternoon. The steady increase during the afternoon is in contradiction to the usual diurnal curves presented elsewhere (Odum and 13 o, l.AG/L piration that resulted ·after subtraction of dif· fusion exchange is plotted with a dashed line. FIG. 2. Diurnal oxygen curve for Pond 4, Points on oxygen curve represent duplicate August 18, 1962. See Fig. 1 for explanation of samples. symbols. Hoskin, 1958; Copeland, Butler and Shelton, 1961; Copeland and Dorris, 1962; and Beyers, 1963}, and diurnal curves of the other ponds in this study (Figs. 1, 2, and 4). In those examples, the maximum rate occurred during the forenoon or early afternoon. The wide disagreement of replicate oxygen concentrations at the dawn sampling period indicates that stratification may have occurred at that time. Ice formed on the surface of the water between the 0300 and the dawn sampling time. Data for the entire study, based on curves like those in Figs. 1, 2, and 3 are presented in Table 1. Gross photosynthetic productivity ranged between 4.4 and 27.4 gm 0 2/ m2 per day and total community respiration ranged between 6.4 and 26.4 gm Oz/m2 per day. Diffusion constants ranged from 0.2 to 2.8 gm Oz/m2 per hour, within the range reported by Copeland ( 1963) for polluted ponds in the same area. EFFECTS OF DECAYING VEGETATION The decay of vegetation in Pond 2 during August resulted m an increase in com· munity respiration (Table 1) . Mr. John Hooser of the Aquatic Biology Laboratory, Oklahoma State University, experimented with some chemicals that resulted in the death of a large amount of the vegetation. Although some of the vegetation escaped death, a large amount of it settled to the bottom, out of the effective light zone, and required oxygen for its respiration and decomposition. The P/R ratio decreased from near unity during the previous sampling times to about 0.5. Fig. 4 shows diurnal curves before and after the vegetation kill. In April, clouds during 10 A 02 14 o, MG/l MG/L / LIGHT \ 12 18 24 TIME Fie. 3. Diurnal oxygen curve for Pond 1, March 15-16, 1962. See Fig. 1 for explanation of symbols. + 0 5 o, CHANGE 00+-~~~-+~~"""'~~~__,,._-~-1 MG/L/HR -0 5 -10 00 06 12 18 24 TIUE Fie. 4. Diurnal oxygen curves for Pond 2 be­fore and after the vegetation was killed by chemi­cals. The curve before the vegetation kill was taken on April 18, 1962 and is indicated by the solid line. The curve after the vegetation kill was taken on August 18, 1962 and is indicated by the dashed line. Graph A is the observed oxygen con­centration, graph B is per cent saturation, and graph C is the rate of change corrected for diffusion. midday caused a depression in the photosynthetic rate, otherwise the diurnal curve in­dicated by a solid line in Fig. 4 was typical of the curves presented by other authors. The diurnal curve after the vegetation kill (dashed curve in Fig. 4) was much like those TABLE 1 Oxygen metabolism of Oklahoma farm ponds Diffusion Constant Metabolism in gm O:/m2 per day Light gm 0 2/m2 per Pond Dale depth in meters hour p R P/R Pond 1 3/ 15-16/ 62 0.90 1.6 17.8 10.8 1.7 4/ 18/62 0.90 0.3 8.0 7.4 1.1 6/27-28/62* 0.77 0.8 8.8 8.4 LO Pond 2t 4/ 18/ 62 2.00 2.8 13.3 15.6 0.9 6/ 27-28/ 62. 1.08 0.6 6.0 7.8 0.8 8/ 18/ 62 1.30 1.3 12.0 23.4 0.5 Pond3 6/27-28/ 62* 0.51 0.2 4.4 6.4 0.7 8/ 18/ 62 0.62 0.6 5.7 8.2 0.7 Pond4 6/ 27-28/ 62. 0.75 0.3 8.1 10.1 0.8 8/ 18/62 1.20 1.4 27.4 26.4 1.1 • Heavy clouds throughout the diurnal period . t Stratified al least through the daylight hours; metabolism of upper layer only. found in polluted waters (Copeland and Dorris, 1962; and Copeland 19631. The slow increase during early daylight hours apparently was the result of oxidation of chemical compounds reduced during the nighttime low oxygen concentrations or the fulfillment of oxygen debts incurred during the night. The reduction of oxygen concentration must be considered when anticipating the use of chemicals to rid the farm pond of wgetation, otherwirn a fish population may be lost when the decaying vegetation uses the oxygen normally available for fish respiration. EFFECT OF A HYPOLIMNION EXPORT SYSTEM ON COMMUNITY METABOLISM Photosynthetic productivity occurs only in the effective light penetration zone; in the case of the stratified pond in this study (Pond 2) the epilimnion. Respiration or oxygen demand occurs in both the euphotic zone and the dark zone (including the bottom). If a body of water is continually stratified, the leak of oxygen from the photosynthetically active zone into the stagnant hypolimnion is constant as physical conditions dictate. However, if the body of water is stratified during the day and mixing during the cooler night the drain of oxygen is intensified during the night. If, in that sort of situation, the oxygen concentration is measured diurnally, the true metabolism of the epilimnion is erroneously measured, especially during the night. The hypolimnion acts as a huge drain on the epilimnionic oxygen supply during the night and lies in waiting during the day. The increased respiration observed between midnight and dawn in Pond 2 I Fig. 4) may be attributed to mixing of the epilimnion and hypolimnion at night following strati­fication during the day. From just after dawn until midnight, metabolism of the epilim­nion was measured but after that time the oxygen demand of the entire water mass mixing together caused the oxygen concentration (as measured in the epilimnion) to decrease at a more rapid rate than during the previous period. This problem could be solved by taking samples at several depths at frequent intervals. Comparison With Other Communities The gro~s photosynthetic productivity range of 4.4 to 27 .4 gm Oz/m2 per day and total community respiration range of 6.4 to 26.4 gm Oz/m2 per day are of the same order of magnitude or higher than similar communities. Copeland et al. (1961) reported 1.1 to 7.3 gm 0 2/ m2 per day photosynthesis and 4.6 to 9.5 gm 0 2/ m2 per day respiration in a small pond on the Oklahoma State University campus. Odum and Hoskin I 1958) re­ported 2.2 to 4.5 gm Oz/m2 per day photosynthesis and 2.1 to 5.2 gm 0 2/ m2 per day respiration in Stewart Farm Pond in North Carolina. Minter and Copeland I 1962) ob­served photosynthesis of zero to 5.9 gm 0 2/ m2 per day and respiration of 8.9 to 49.6 gm Oz/m2 per day in a pond in Kansas. The high respiration value occurred after a heavy leaf fall in the adjacent area and was undoubtedly caused by their decay. Sitaramiah (1961) reported photosynthetic productivity values of 5.7 to 8.6 gm 0 2/ m2 per day for the Tatayya gunta pond in southern India. Higher productivity and respiration have been reported for polluted waters. Odum ( 1956) reported a photosynthetic productivity of 60 gm 0 2/ m2 per day in the polluted White River, Indiana. Copeland and Dorris (1962) reported photosynthesis as high as 23.4 gm 0 2/ m2 per day and respiration of 30.2 gm 0 2/ m2 per day in ponds polluted with oil refinery effiuent. Copeland ( 1963) reported photosynthesis of 29.2 gm 0 2/ m2 per day and respiration of 50.5 gm 0 2/m2 per day in oil refinery effluent holding ponds. Photo­synthesis of 36 gm 0 2/m2 per day and respiration of 36 gm 02/m2 per day have been reported for sewage oxidation ponds in South Dakota (calculated from Bartsch and Allum, 1957). Acknowledgments We acknowledge and appreciate the assistance of Mr. John L. Butler of the Aquatic Biology Laboratory at Oklahoma State University, Stillwater, Oklahoma_ The facilities and equipment of the Aquatic Biology Laboratory were used during the study. Dr. H. T. Odum, Institute of Marine Science, University of Texas, Port Aransas, Texas, criticized the mauscript. Literature Cited A. P. H. A. 1960. Standard methods for the examination of water and waste-water. Amer. Pub!. Health Assn. 11th ed. 626 p. Bartsch, A. F., and M. 0. Allum. 1957. Biological factors in the treatment of raw sewage in arti­ficial ponds. Limnol. &Oceanogr. 2: 77-84. Beyers, R. J. 1963. A characteristic diurnal metabolic pattern in balanced microcosms. Puhl. Inst. Mar. Sci. Univ. Tex. 9: 19-27. Copeland, B. J. 1963. Oxygen relationships in oil refinery effluent holding ponds. Ph.D. Thesis. Okla. State Univ., Stillwater, Okla. llO p. Copeland, B. J., J. L. Butler, and W. L. Shelton. 1961. Photosynthetic productivity in a small pond. Proc. Okla. Acad. Sci. 42: 128-132. Copeland, B. J., and T. C. Dorris, 1962. Photosynthetic productivity in oil refinery effluent holding ponds. J. Water Poll. Control Fed. 34: 1104-1111. Minter, K. W., and B. J. Copeland. 1962. Oxygen relationships in Lake Wooster, Kansas during wintertime conditions. Proc. Kan. Acad. Sci. 65(4): 452-462. Odum, H. T. 1956. Primary production in flowing waters. Limnol. & Oceanogr. 1: 102-107. Odum, H. T., and C. M. Hoskin. 1958. Comparative studies on the metabolism of marine waters. Puhl. Inst. Mar. Sci. Univ. Tex. 5: 16-46. Sitaramiah, P. 1961. Studies on the physiological ecology of a tropical fresh water pond community. Ph.D. Thesis. Sri Venkateswara Univ., Tirupati, India. 186 p. New Additions to the Bryozoan Fauna of the Gulf of Mexico ROBERT LAGAAIJ Koninkliijke/Shell Exploratie en Produktie Laboratorium, Rijswijk, The Netherlands Abstract This paper deals with thirty-four species of bryozoa which had not been before recorded from the Gulf of Mexico and the north side of the Straits of Florida. These new additions to the fauna bring the total number of Bryozoan species recorded from the area under consideration to 216. Six other species, already previously known, are also discussed on account of taxonomical or zoological questions involved. They are marked with an asterisk in the following list. List of species recorded in this paper Aetea anguina Hippopodina bernardi sp. nov. Membranipora tenuissima Arthropoma cecilii Conopeum commensale •Cribellopora trichotoma Electra monostachys Escharina vulgaris Electra bellula *Cleidochasma contracta Antropora typica Hippoporella gorgonensis Setosellina goesi Hippodiplosia americana *Retevirgula tubulata Exochella longirostris P arellisina latirostris Smittoidea reticulata *Chaperia patula Codonellina montferrandii Floridina parvicella Parasmittina signata Monoporella divae Phoceana acadiana sp. nov. Setosella vulnerata Lekythopora longicollis sp. nov. Euginoma cavalieri sp. nov. C repidacantha poissonii var. teres Beania hirtissima Vittaticella uberrima Scrupocellaria harmeri Halysisis diaphana Caberea boryi •Fedora nodosa Figularia contraria sp. nov. *Crisulipora occidentalis Bellulopora bellula Stomatopora trahens Chorizopora brongniartii ldmidronea fiexuosa Introduction In view of the amount of previous work on the subject, one might suppose the bryozoan fauna of the Gulf of Mexico to be one of the best known in the world. Recently Osburn (1954), in a summary of the state of our knowledge gained over a period of almost 90 years, arrived at a total of 170 species of Bryozoa known from the Gulf. The addition, through this paper, of 34 species which had so far escaped notice in this area would seem all the more surprising. For a better understanding it is necessary to realize with Osburn (1954, p. 362) that the existing collections were made almost entirely from the Eastern Gulf of Mexico. In fact most of the collecting was done in an even more restricted area near the southern end of the Florida Peninsula. Hitherto only eight species have been recorded from the Western Gulf, Nellia oculata (Levinsen, 1909, p. 121), Conopeum tubigerum (Osburn, 1940, p. 352), Membranipora tuberculata, Acanthodesia savartii, Bugula turrita, Bugula neritina (Hedgpeth, 1950, p. 84), Membranipora fiabellata (Ladd, 1951, p. 139) and Acanthodesia tenius (Ladd, Hedgepth and Post, 1957, p. 615). Most groups of marine organisms (the Foraminifera are a notable exception) appear to suffer from this lack of data from the Western Gulf, as one gathers from the various contributions in "Gulf of Mexico, its Origin, Waters and Marine Life," edited by Galtsoff ( 1954) . More than half of our new records come from this unexplored area. The geographical term "Gulf of Mexico" has here been taken in the restricted sense propo£ed by Galtsoff (l.c., p.v), i.e. as having the line Caho Catoche-Key West as its south. eastern boundary. The dividing line between the Eastern and the Western Gulf of Mexico in this paper coincides with the meridian of 89° W. A second source of new finds was located in a very different sector. Nearly all the ma· rine bottom samples investigated (Appendix) were not available to the author in their original state, but as washed residues. Such residues are obtained by washing a given amount of the sample over a set of sieves with progressively diminishing mesh-size, a routine procedure in the preparation of samples for foraminiferal analysis. It is not the first time that scanning the finer residue fractions, notably the 250--590µ, fraction, has provided the author with a number of small-sized species which had previously remained unnoticed in a fauna (Lagaaij, 1959) . The new Gulf records of the genera Chorizopora, Vittaticella and Halysisis owe their presence in this paper to their showing up in these finer residue fractions. Osbum's total number of 170 species needs correction in several ways. Primarily the restriction of the term "Gulf of Mexico" (see above) excludes a number of species from his survey, viz. those recorded from the shallow platform E of the Yucatan Peninsula (Canu and Bassler, 1928a), and those from the deeper waters N of Cuba (De Pourtales, 1867; Smitt, 1872, 1873; Canu and Bassler, 1928a). Nevertheless, perusal of the pertinent literature gives a slightly larger figure, as the following breakdown will show : De Pourtales ( 1867) 1 Hastings (1932) 1 Smitt ( 1872, 1873) 89 Osburn ( 1940) 3 Hincks ( 1880b) 2 Hastings ( 1943) 1 Busk (1884) 1 Osburn (1947) 2 Osburn (1914) 41 Silen (1947) 1 Canu and Bassler (1928a) 40 TOTAL 182 In this list the figure after each name indicates the number of species which constitute new Gulf records by the respective author, whether given under their proper name or not. Osburn (1914), for instance, who listed a total of 78 species from the Tortugas, included 41 species which had not been previously known to De Pourtales, Smitt, Hincks, or Busk. In drawing up this list allowance was made for those cases in which authors included two or more different forms under one name, or in which one species has been given under two different names by the same author. Thirty.four species are here described which had not before been recorded from the Gulf of Mexico and the north side of the Straits of Florida. This brings the total number of known Gulf species to 216, a figure comparable with that established for Brazil (Marcus, 1953). In both areas the deeper waters, beyond the 100 or even the 50 fathom isobath, remain virtually unexplored. The types and the figured specimens have been deposited in the Department of Geology, United States National Museum, Washington, D.C. The corresponding USNM catalogue numbers are given in the text and in the Index to Plates. There is a second group of catalogue numbers, each number consisting of four ciphers separated by full stops; these are used in the text without additional explanation and refer to specimens kept in the Department of Zoology of the British Museum (Natural History). Systematics Family AETEIDAE SMITT, 1867 Genus Aetea Lamouroux, 1812 Aetea anguina (Linnaeus) (Pl. VIII, Fig. 1) Sertularia anguina Linnaeus ( 1758, p. 816). Aetea anguina Busk (1884, p. 2), Duerden (1896, p. 270) , Robertson (1905, p. 244, pl. 4, figs. 1-4), Osburn (1912, p. 220, pl. 21, figs. 14, 14a), Marcus (1921, p. 114, text-fig. 15) , O'Donoghue and O'Donoghue ( 1926, p. 85), Hastings ( 1930, p. 702), Osburn (1933, p. 306, pl. 15, fig. 12) , Marcus (1937, p. 26, pl. 5, fig. 8), Osburn ( 1940, p. 345, pl. 1, fig. 8), Hastings ( 1943, p. 471, text-figs. 57a-c), Osburn (1944, p. 28, text-fig. 17), Osburn (1950, p. 11, pl. 1, fig. 3), Marcus (1953, p. 278, cum syn.), Maturo (1957, p. 32, text-fig. 24) , Soule ( 1959, p. 2). Material American fossil distribution Locality 64. Several colonies, incrusting around unidentified flexible stems. Washed ashore. Occurrence North-western Gulf: Galveston Island, Texas. Amerz'.can distribution Mount Desert Island, Maine Woods Hole, Macs. Mouth of Chesapeake Bay, Virginia Beaufort, North Carolina Bermuda 5-6% fathoms 1-19 fathoms 2 fathoms 30 fathoms Guanica Harbor, Puerto Rico 10 fathoms Kingston Harbour, Jamaica Bay of Santos, Guaruja, etc., Brazil 0--17 metres Espirito Santo, Brazil 35 metres Patagonia 50--80 metres Falkland Islands 74-75 metres Chili 45 fathoms Juan Fernandez Islands Peru (-Oregon) 0--30 fathoms Galapagos Islands 5-12 fathoms Gulf of California 0--22 fathoms California Oregon (-Peru) 0--30 fathoms British Columbia 10--15 fathoms Upper Eocene (Ocala Limestone) of Ocala, Florida and of Bainbridge, Georgia. Family MEMBRANIPORIDAE BUSK, 1854 Genus Membranipora De Blainville, 1830 Membranipora tenuissima Canu (Pl. 1, fig. 2) Membranipora tenuissima Canu ( 1908, p. 253, pl. 2, figs. 9, 10). Material Locality 4 ( 1) , 31 ( 1) , 109 ( 1) , 226 (1) . Fossil material Pleistocene of Shell-Continental Federal Block A-72, High Island Area, offshore well; 1210--1240' (ditch cuttings) . 1 specimen. Ibidem, 1270--1300' (ditch cut­tings). 1 fragment. Remarks The most distinctive feature is the remarkable partial closure of the apertural area in some zooecia, brought about by marginal calcification underneath the ectocyst. In these partially occluded zooecia the former position of the operculum is outlined by an.shaped shallow depression in the distal part of the calcified area. I am grateful to Dr. Anna B. Hastings, who has brought Canu's description and figures of M. tenuissima, from the Post-Pampean of the Argentine, to my attention. The partially occluded zooecia with their characteristic distal depression shown by Canu are unusual among Recent Membraniporidae so tha_t the odds are in favour of this being indeed the same species. It is probable that these arcuate impressions have not received their full proximal extension on Canu's touched-up photographs. They now appear too shallow to fit the distal outline of the operculum. Of the two pairs of septula in the lateral walls of the zooecia, the distal ones tend to be larger, and to become more conspicuous with increasing irregularity of incrustation. Zooeciules, always associated with irregular incrustation, are particularly common in the Epecimen from Grand Isle, Louisiana, which is found encrusting a multilamellar colony of Conopeum commensale. A row of widely spaced spine bases, to a maximum of five on each side, is sometimes placed along the zooecium near the interzooecial groove. They are present, although not on all zooecia, in the more complete specimens from Grand Isle, Corpus Christi Bay, and from the Federal Block A-72 offshore well (1210­1240' and 1270-1300'). In two of our specimens, viz. from Cavalier Station 2 and from the Federal Block A-72 offshore well (1270-1300') two successive growths are apparent in the calcareous closure, which suggest that calcification took place in stages. Rows of unequally spaced small dots are present on the boundary line between these growth stages and the question has arisen whether these markings are the bases of small apertural spines or just pores in the calcareous closure. I agree with Dr. Hastings, who has kindly examined the speci­mens, that the latter possibility is more likely. The distributional picture one gathers from the Gulf coast is that this species is clearly confined to the very shallow brackish inshore and offshore waters. The fragmentary Sabine Bank specimen from Locality 109, taken at 12% fathoms, seems to contradict this conclusion. It differs markedly in preservation, however, from the rest of the as­semblage collected at this locality. This fragment, therefore, probably did not occur in situ, but is interpreted as derived from brackish coastal deposits associated with the coastline of one of the rising sea level stages during the Early Holocene. Occurrence North-western Gulf: Corpus Christi Bay, Texas Off Freeport, Texas Sabine Bank Gulf beach of Grand Isle, Louisiana % fathoms 6% fathoms 12% fathoms Fossil occurrence Pleistocene of Shell-Continental Federal Block A-72, High Island Area, offshore well, 1210-1240' (ditch cuttings); ibidem, 1270-1300' (ditch cuttings). Fossil distribution Post-Pampean (Holocene), Puerto Militar, Bahia Blanca, Argentine. Genus Conopeum Gray, 1848 Conopeum commensale Kirkpatrick and Metzelaar (Pl. VIII, fig. 2) Conopeum commensale Kirkpatrick and Metzelaar ( 1922, p. 985, pl. 1, fig. 1, 4--6, 9), Marcus ( 1937, p. 35, pl. 5, fig. 13), Marcus ( 1938a, p. 16, pl. 3, figs. 6a-c), Marcus (1939, p. 126, pl. 6, figs. 5a-b, 6), Osburn (1950, p. 30, pl. 2, figs. 12-15), Soule and Duff (1957, p. 91), Maturo (1957, p. 36, text-fig. 29), Soule (1959, p. 7) . Membranipora fusca Canu and Bassler (1925, p. 11, pl. 2, figs. 6-8). Material Locality 4(9), 5 (several), 10 ( 1), 13 ( 6), 26( 1), 28 (several on gastropod), 36 ( 1), 60-63, 65 (several), 67(1), 77(4), 78(1), 86(1), 108(4), 110(2), 120(1), 126 ( 8)' 132 ( 1) ' 226 ( 2) . Remarks The following criteria serve to identify this species: the thick, multilamellar incrusta­tion on gastropod and pelecypod shells, the fusion of the gymnocystal tubercles into prominent "rectangular blocs" in the older zooecia, the thin dark brown lines marking the zooecial boundaries, the great distance between the frontal and dorsal walls, and the occasional presence of chitinous spinules on the frontal membrane. Unfortunately, these characters are seldom united in one specimen. Multilamellar incrusting specimens are at hand from the Gulf beaches of Grand Isle, Louisiana, and Galveston Island, Texas. Those available from St. Joseph Island, Texas, are either unilamellar incrusting, or growing upward in pseudovinculariiform growth around unidentified flexible stems. In the Cavalier grab-samples from the inner part of the continental shelf several smaller fragments occur, which I believe also belong to this species. They are characterised by the great distance between the frontal and dorsal walls and/ or by the "brown lines" of the original description. This appears to he a common inner neritic species in the North-western Gulf of Mexico, where salinities are somewhat reduced and subjeCt to seasonal variation. It has not been found on the shelf of peninsular Florida, where open Gulf salinities ( > 359'00) extend practically up to the beaches and remain remarkably constant throughout the year (Fig. 1). Occurrences North-western Gulf: Corpus Christi Bay, Texas; NW Gulf of Mexico beaches from St. Joseph Island, 10' Frc. 1. Distribution of average salinities in the upper 50 metres in the Gulf of Mexico (after Parr, 1935). Texas to Grand Isle, Louisiana; and at various offshore stations in the NW Gulf 0-20 fathoms. Distribution Cape Blanco, West Africa Port Etienne, Mauritania Beaufort, North Carolina Bay of Santos; Guaruja; ltanhaen, Brazil Gulf of California Pacific Coast of America from Lower California (Mexico), Costa Rica, and La Plata Island, Ecuador 5-10 fathoms 61/z fathoms } in shallow water and on the beaches 5-40 fathoms 2-45 fathoms Fossil distribution Pleistocene of Newport, California. Family ELECTRIDAE STACH, 1937 Genus Electra Lamouroux, 1816 Electra monostachys (Busk) (Pl. I, fig. 1) Membranipora monostachys Busk (1854, p. 6L pl. 70, figs. 1-4) , Jullien (1881, p.168), Calvet (1904, p. 13), Osburn (1912, p. 227, pl. 22, figs. 29, 29a; non pl. 22, fig. 29b, pl. 30, fig. 87 = E. crustulenta (Pallas), var. aretica Borg). Electra monostachys Canu and Bassler (1923, p. 17, partim, pl. 29, figs. 2, 3, non 1), Hastings ( 1930, p. 706), Osburn ( 1933, p. 20, pl. 15, fig. 13). Electra hastingsae Marcus (1937, p. 39, 40), Marcus (1938a, p. 17, pl. 2, fig. 7), Osburn ( 1944, p. 39, text-fig. 24, cum syn.), Rogick and Croasdale ( 1949, p. 55, figs. 27, 28) , Osburn ( 1950, p. 38), Maturo ( 1957, p. 38, text-fig. 31) . Material Locality 5 ( 1), 16 ( L markings on shell fragment only), 23 ( 1), 55 ( 1), 60-63 (several), 119(1). Fossil material Pleistocene of Western Natural Gas Company offshore well, St. Tr. 608#1, Mata· gorda Area, Texas, 410-440' (ditch cuttings). 1 specimen. Remarks The mode of incrusting in E. monostachys is usually monoserial-pluriserial. The sheetlike incrustation observed in our figured specimen from Galveston Island is rare and has only been reported from the Bay of Santos, Brazil (Marcus, 1938a, p. 17) . It is interesting to observe, in the same specimen, that whereas most of the apertural spines are still intact the stouter, erect ones: the distal pair flanking the orifice and the single median spine on the proximal gymnocyst tend to break off more easily than the more delicate paired incurved spines which line the lateral borders. The distribution pattern of E. monostachys along the Texas and West Louisiana coast confirms the habitat already on record in the literature: it is a species typical of the very shallow inshore waters of somewhat reduced salinity, such as found in the mouth of rivers, in estuaries, bays and inlets. In the original description of E. monostachys, Busk (1854, p. 61) gives the British habitat of the species as "Britain (east coast?). In the mouths of rivers and estuaries, [or in brackish water], spreading upon shells and stones, [some­times erect, free, foliaceous and contorted]." Dr. Anna B. Hastings has informed me (in litt.), that the bracketed parts of this sentence refer to the specimen found by Mr. Higham (see Busk, 1854, p. 62) which belongs to E. crustulenta and (unpublished in­formation) came from a brackish ditch. The greatest recorded depth of E. monostachys is 35 m ( 19 fathoms). It is interesting to consider the North American distribution of the species (Fig. 3). In spite of the fact that the faunas around southern Florida have been rather extensively studied in the past, E. monostachys has never been recorded from that region. It is also conspicuously absent among the shallow assemblages of Tampa Bay, Fla., which were studied in some detail by the author. Along the North America Atlantic coast the species has been observed at a number of localities between the Mount Desert, Maine region and Beaufort, North Carolina, but not south of the last mentioned locality. The resulting discontinuity along the North American coastline suggests that in the NW Gulf of Mexico E. monostachys is a Pleistocene relict form, which has survived since Pleistocene times only in the inshore waters of the Texas and West Louisiana coast. A prerequisite for this interpretation is that the species should have inhabited the Gulf area in Pleistocene times. Direct proof for this is the occurrence of E. monostachys in the Pleistocene of the Texas offshore region: Western Natural Gas Company, St. Tr. 608#1, Matagorda Area, Texas, 410--440' (ditch cuttings). Pleistocene relict forms in the NW Gulf of Mexico are well known among several other groups of marine organisms, notably the hydroids (Deevey, 1950), gorgonians (Bayer, 1954) and fishes ('Rivas, 1954) . This is the first time that they are recognized as such among the Bryozoa in this area. Some authors assume that these disjuncts have survived because of the warm-temperate rather than tropical or subtropical winter temperature of the shallow water in this part of the Gulf of Mexico (Ekman, 1953, p. 55) and that the discontinuity around the Florida Peninsula is caused by a thermal barrier (Deevey, 1950). Since the disjunct Bryozoa are typically brackish (polyhaline) species, I have argued elsewhere in this paper (p. 194) that the barrier to free dispersal around the Florida Peninsula is perhaps of a saline rather than a thermal nature. Occurrence North-western Gulf: Corpus Christi Bay, Texas off Freeport,Texas Gulf beach of Galveston Island, Texas Sabine Bank 5/(; fathoms 4--8% fathoms 7 fathoms Fossil occurrence Pleistocene of Western Natural Gas Company offshore well, St. Tr. 608 # 1, Matagorda Area, Texas, 410-440' (ditch cuttings). American distribution Mount Desert Island, Maine Woods Hole, Mass. New Rochelle, New York New Jersey Ocean City, Maryland Chincoteague Bay Mouth of Chesapeake Bay, Virginia Beaufort, North Carolina Balboa, Panama Canal Zone Bay of Santos, Brazil Magellan 2-19 fathoms on Fucus and Laminaria Low tide level on Mytilus in shallow water American fossil distribution Pliocene of South Carolina Pleistocene of Santa Barbara, California Electra bellula (Hincks) Membranipora bellula Hincks (188la, p. 149, pl. 8, fig. 4). Electra bellula Marcus ( 1937, p. 37, pl. 6, figs. 14A, B, D, E, F, non fig. 14C = var. bi· cornis Hincks), Osburn (1940, p. 355), Marcus (1953, p. 280). Remarks Dr. A. B. Hastings has found a small specimen of E. bellula, associated with Electra tenella (Hincks) and Bifiustra savartii (Audouin), on the type slide of E. tenella: 99.5.1.648, Hincks Coll., from Florida, "on weed (Miss Jelly)," depth not indicated. In the North-western Gulf of Mexico E. tenella and B. savartii are both found in the inner neritic zone (0-120'), where salinities are normally somewhat reduced and subject to seasonal variation. Therefore there is some reason to believe that the "weed" was ob­tained from an estuary or lagoon, in shallow water of somewhat reduced and variable salinity, rather than off peninsular Florida where ocean salinities extend practically up to the beaches. The distribution, as given below, was largely compiled from the records in the species register (Polyzoa) in the Zoological Department of the British Museum (N:H.) , and does not include the varieties bicornis Hincks and multicornis Hincks. Occurrence Florida (99.5.1.648, Hincks Coll.) Distribution Australia Indian Ocean Red Sea Madagascar Cape Verde Islands Puerto Rico Pernambuco, Brazil Espirito Santo, Brazil Bay of Santos, Brazil Family HINCKSINIDAE CANU AND BASSLER, 1927 Genus Antropora Norman, 1903 Antropora typica (Canu and Bassler) (Pl. I, fig. 3) M embrendoecium strictorostris Canu and Bassler ( l 928a, p. 23, pl. 2, fig. 7). Dacryonella typica Canu and Bassler (1928a, p. 57, pl. 5, figs. 4.--8, pl. 32, figs. 11-12), Canu and Bassler ( l 928c, p. 65, pl. 1, fig. 10) . Canua typica (Canu and Bassler) Osburn ( 1940, p. 358). Material Locality 94(1), 150(8), 379(3) , 411 (1), 444(2). Remarks It is reasonably certain that Canu and Bassler in their Gulf of Mexico paper ( l 928a) described a Cuban deeper water species under two different names: Membrendoecium strictorostris and Dacryonella typica. This view is supported by the combination of the following facts: 1. According to modern views (cf. Osburn, 1950, pp. 51-52) both forms are now referable to Antropora Norman, 1903, and therefore at least congeneric. 2~ The single occurrence of M. strictorostris was at Albatross Station D.2319, north of Cuba, 143 fathoms. D. typica was recorded from the same sample. 3. The two forms correspond in detail such as in the aspect of the small entozooecial ovicell and in form, size, position and orientation of the avicularia. It would seem appropriate to retain the specific name of the form figured in most detail, which is typica. Although this species is normally found encrusting a solid substratum, the two speci­mens taken SSW of John's Pass, Florida in 34 fathoms are pseudovinculariiform, i.e. consist of erect, hollow-cylindrical branches. Occurrence North-western Gulf: Cavalier 1956 Station 316 50 fathoms Cavalier 1956 Station 278 38 fathoms Eastern Gulf: Atlantis 1951 Station 154 64 fathoms Vema-3 1954 Dredge #1 117 fathoms SSW of John's Pass, Florida 34 fathoms Distribution North of Cuba 130-167 fathoms Off Campos, Brazil 70 fathoms Fossil distribution Pliocene of Bocas Island, Almirante Bay, Panama New Additions w the Bryozoan Fauna of the Gulf of Mexico Genus Setosellina Calvet, 1906 Setosellina goesi (Silen) (PL II, fig. 1) H eliodoma goesi Silen ( 1942, p. 2, pl. 1, figs. 3, 4) . Vibracellina caribbea Osburn (1947, p. 11, pl. 1, figs. 1, 2). Material Locality 89(2), 99(2), 102(1), 109(1), 150(6), 179(63) , 181(2) , 354(3), 357(2), 358(3), 359(6), 360(4), 361(19), 363(1), 367(43), 369(1), 377(4), 379(1), 380(24), 381(13), 382(33), 383(72), 384(20), 385(97), 389(1), 390( 1)' 391 ( 12)' 392 (30)' 393 ( 4)' 395 (2)' 411 (37)' 412 (7)' 417 (4), 442 ( 4), 443(5) ,444(5) ,458(1) , 458a(l) , 461(1) , 464(13) , 465(1). Remarks The two "concentric" spirals of zooecia springing from the ancestrula described by Silen are easily recognized in juvenile specimens. Both left and right rotational spirals occur. The bispiral arrangement in the ancestrular region is also apparent in one of the type figures of Vibracellina caribbea Osburn (1947, pl. 1, fig. 2), which is here repro­duced in amended form (Fig. 2). As seen in this figure, the ancestrula sometimes gives off two vibracula, each of which marks the beginning of a spiral. In adult colonies, which sometimes completely envelop their supporting object, the bispiral arrangement is usually obscured as the zoarium adapts itself to the shape of its substratum by repeated branching of the spirals. It is interesting to observe that the rotational direction of the spirals is rigorously Fie. 2. Setosellina goiisi (Silen). Ancestrular region of a right rotational specimen. This is the original type figure of Vibracellina caribbea Osburn, with arrows added. The large arrows follow the concentric spiral arrangement of the zooecia. The small arrows indicate the largest of the two vibracular teeth. reflected in 1) the orientation of the larger vibracular tooth, and therefore of the vibracular seta, as indicated by the small arrows in Fig. 2, and in 2) the position of the vibracula with respect to the median line of the parent zooecia. Thus it remains possible to distinguish a left from a right rotational specimen, in which the original bispiral arrangement has become obscured, from the orientation and position of the vibracula. A small septular pore is always present in the angles between the vibraculum and the adjacent zooecia on either side at the growing edge of the zoarium. In Setosellina roulei Calvet ( 1906, p. 157; 1907, p. 395, pl. 26, figs. 5, 6) the type species of Setosellina Calvet, 1906, from the Cape Verde Islands, and in Setosellina constricta Harmer (1926, p. 264, pl. 16, fig. 1) from the Malay Archipelago, the vi­bracula do not occur distinctly outside the median line of the parent zooecia. Osburn (1947), when introducing Vibracellina caribbea from the southern part of the Caribbean, was evidently unaware of Silen's earlier paper, published in war-time Europe, in which the same form was described as Ifeliodoma goesi from the West Indies. Both authors have independently considered the possibility of the Recent West Indian­Caribbean species being identical with Vibracellina laxibasis Canu and Bassler ( 1928, p. 23, pl. 32, fig. 2), from the Pliocene of Bocas Island, Almirante Bay, Panama. Examination of the syn types of Vibracellina laxibasis (U.S.N.M. Cat. No. 70868, 9 speci­mens) in the U.S. National Museum reveals, better than the type figure, that the orienta­tion of the vibracula is by no means as regular as is the case in Setosellina goesi. Setosellina goesi is clearly more at home in the Eastern Gulf and in the Straits of Florida than it is in the North-western Gulf of Mexico, and this may be a matter of outspoken preference for a carbonate sand bottom. Although occasionally found en­crusting coarse quartz grains, its usual small support is calcareous: altered (black) carbonate particles, fragments of calcareous algae and of molluscs, echinoid spines, and sometimes the tests of the Foraminifera Amphistegina gibbosa d'Orbigny and Globoro­talia menardii (d'Orbigny). The discriminating power of the larva in seldom selecting its supporting object too large is indeed remarkable. Six of the seven occurrences in the North-western Gulf are located in the direct vicinity of topographic highs (banks) near the edge of the continental shelf with their apron of carbonate detritus. Occurrence North-western Gulf: seven stations, mostly located in the direct vicinity of topographic highs (banks) 12%-70 fathoms Eastern Gulf and Florida Straits: numerous stations 8%-196 fathoms Additional occurrence Caroline 1933 Station 10, near San Juan, Puerto Rico, 100 fathoms. 3 specimens. Distribution Virgin Islands 300--480 metres Anguilla 200-375 metres Cape la Vela, Colombia 10 fathoms Gulf of Venezuela ) Aruba 19-41 fathomsTortugas Margarita New Additions to the Bryozoan Fauna of the Gulf of Mexico Family CALLOPORIDAE NORMAN, 1903 Genus Retevirgula Brown, 1948 Retevirgula tubulata (Hastings) (Pl. I, figs. 4-6) Hincksina periporosa Canu and Bassler (1928a, p. 22, partim, pl. 2, fig. 11, non figs. 8-10 = Retevirgula periporosa Canu and Bassler sp.), ?Osburn ( 1940, p. 356, pl. 2, figs. 18, 19). Pyrulella tubulata Hastings (1930, p. 709, pl. 6, figs. 20-26), Osburn (1947, p. 14). Retevirgula tubulata Osburn ( 1950, p. 86, pl. 8, fig. 1), Soule ( 1959, p. 17). Material Locality 99(1), 15011) , 179(27), 180(1), 379(1), 382(2), 383(3), 386(2), 38713)' 388 (2)' 443 (2) ' 444( 1)' 464(1). Remarks I ha,-e examined most of the material listed under the original description of Hincksina periporosa Canu and Bassler ( 1928a, p. 23) which is kept in the U.S. National Museum in Washington, D.C. Only the specimen(s) from Albatross Station D.2167, off Habana, Cuba, 201 fathoms, was not found. It appears that there are two (and possibly three) species involved.1 The greater part of this material, i.e. the specimens from the Gulf of Mexico (Albatross Station D.2405), the Straits of Florida (Albatross Station D.2639, including two exchange specimens now in the British Museum (N.H.), 32.3.7.31) and an additional Western Atlantic sample (Albatross Station D.2612, E of Wilmington, N.C., 52 fathams) was found to belong to R. tubulata. Only the two Cuban specimens from Albatross Station D.2319, marked "Cotypes" (U.S.N.M. Cat. No. 7519), on which the type figures 8-10 were based, represent genuine R. periporosa. In order to make the position quite definite, one of the two Cuban "Cotypes," which has been circled in red on the actual specimen and which has been figured by Canu and Bassler in pl. 2, fig. 10 of their Gulf of Mexico paper (1928a) with part of its spines still intact, is hereby chosen as the lectotype of Hincksina periporosa. As established on the Cuban specimens, the ovicells of R. periporosa are small, hyper­ stomial and reduced rather than entozooecial (as implied in Canu and Bassler's reference of this species to Hincksina; cf. Marcus, 1949, p. 7), with a fair-sized circular foramen facing entirely distally. In some cases the promixal lip of the ovicell has grown out vertically into a conspicuous triangular hood. The ovicells of R. tubulata, on the other hand, have been described and figured by Hastings ( 1930). They are large, hyperstomial and the large circular foramen occupies a frontal position. The proximal lip is only very slightly out-turned. Another difference is found in the arrangement of the spines. As far as I have been able to make out on the lectotype specimen of R. periporosa in which part of the spines are still preserved, there is no such differentiation in the orientation of the spines which 1 Two of the three specimens from Albatross Station D.2405, Gulf of Mexico, 30 fathoms (U.S.N.M. Cat. No. 7520) do not seem to belong either to Retevirgula periporosa or to R. tubulata; the third specimen, marked "Cotype," belongs to R. tubulata and was used for pl. 2, fig. 11 of the Gulf of Mexico Memoir (Canu and Bassler, 1928a). The explanation of pl. 2 is, therefore, inaccurate. The following corrections should be made: pl. 2, figs. 8, 9, 10 refer to specimens (of Retevirgula peri­porosa) from Albatross Station D.2319, north of Cuba, 143 fathoms (U.S.N.M. Cat. No. 7519); pl. 2, fig. 11 refers to a specimen (of R. tubulata) from Albatross Station D.2405, Gulf of Mexico, 30 fathoms (U.S.N.M. Cat. No. 7520). surround the op~sia as there is in R. tubulata (cf. Hastings, 1930, p. 710). They are all erect and only slightly curved inward over the opesia. Whether Osburn's (1940) shallow water form taken at 20 fathoms off Guanipa Harbor, Cuba and at 2 fathoms in Bermuda was correctly identified as R. periporosa, or whether it also belongs to R. tubulata, cannot be ascertained at present. In view of the shallow depth the latter possibility seems more likely. Occurrence North-western Gulf: Cavalier 1956 Station 311 70 fathoms Cavalier 1956 Station 278 38 fathoms Cavalier 1956 Station 227 371;2 fathoms Cavalier 1956 Station 228 271;2 fathoms Eastern Gulf: Atlantis 1951Stations154, 157-158, 161-163 20-64 fathoms Vema-3 1954 Dredge #2 29 fathoms SSW of John's Pass, Florida 34fathoms Florida Straits: E of Triumph Reef 45 fathoms Additional occurrence Albatross Station D.2612, E of Wilmington, N.C. (U.S.N.M.) 52 fathoms Distribution Gulf of Mexico 30 fathoms Florida Straits 56 fathoms ?Puerto Rico 20 fathoms ?Bermuda 2 fathoms Aruba 23 fathoms Galapagos 4, 12 fathoms Gorgona, Columbia 30 fathoms American Pacific coast from Angel de la Guardia Island, Gulf of California to Gorgona, Columbia shallow water to 80 fathoms Genus Parellisina Osburn, 1940 Parellisina latirostris Osburn (Pl. VIII, fig. 3) Parellisina latirostris Osburn ( 1940, p. 361, pl. 4, figs. 33, 34), Osburn (1949, p. 5, fig. 4). Material Locality 68(1), 69 (7 fragments, probably all part of one large specimen, originally incrusting a smooth,. rounded, fist-size cobble. 88(6), 94(1), 386(2), 387(2), 388(2) . Remarks The characteristic avicularium and corresponding distal kenozooecium have only been found in a specimen from Locality 69 and from Locality 88, located at Stetson Bank and Claypile Bank respectively. Of the remaining specimens and fragments the identification must necessarily remain somewhat uncertain. New Additions to the Bryozoan Fauna of the Gulf of Mexico Occurrence North-western Gulf: Stetson Bank area approx. 30 fathoms Cavalier 1956 Station 322 23 fathoms Cavalier 1956 Station 316 50 fathoms Eastern Gulf: Atlantis 1951Stations161-163 20-22 fathoms Distribution Puerto Rico 7-27 fathoms Family CHAPERIIDAE JULLIEN, 1888 Genus Chaperia Strand, 1928 Chaperia patula (Hincks) (Pl. II, fig. 2) Membranipora patula Hincks (188la, p. 150, pl. 9, fig. 4) , Hincks (1882, p. 465), Robertson (1908, p. 263) , O'Donoghue and O'Donoghue (1923, p. 25) . Chaperia galeata (Busk) Canu and Bassler (1923, p. 52, partim, pl. 34, figs. 9, 10, non fig. 8 = Chaperia californica Osburn), Canu and Bassler (1928a, p. 155), Maturo (1957, p. 39, text-fig. 33). Chapperia patula Osburn (1950, p. 89, pl. 10, figs. 1, 2), Soule and Duff (1957, p. 96, cum syn.), Soule (1959, p. 20) . Material Locality 2(2), 93(1), 94(4), 95(5), 99(12), 102(12), 150(1), 179(1), 181(7), 193 (1)' 332 (1)' 378 (5)' 379 (1)' 380(1) ' 383 ( 4)' 384(10), 411 (1)' 412 (5)' 443(2) . Remarks Our fragmentary specimens are perfectly identical in their zooecial characters with the specimen from Albatross Station D.2405, Gulf of Mexico, 30 fathoms (U.S.N.M. Cat. No. 7475, identified by Canu and Bassler (1928a, p. 155) as Chaperia galeata (Busk), and with two other specimens from the same locality simply labelled "Chaperia," in the U.S. National Museum. The much larger Albatross specimens are all erect and dichotomously branching. Our figured specimen (Pl. II, fig. 2) is incrusting. The only reference which Canu and Bassler gave in 1928 was to Chaperia galeata (Busk) Canu and Bassler (1923, p. 52) , i.e. to fossil material now split up between C. patula (Hincks) and C. californica (Osburn)-see Osburn, 1950, p. 89, 91. No doubt the Recent Chaperia from the Gulf of Mexico belongs to C. patula (Hincks) . Our specimens have the large dimensions and the shelf-like extension of the occlusor­laminae inside the opesia described by Osburn (1950, p. 90). The occlusor-laminae end proximally in a pair of raised, rounded knobs, a condition strikingly similar to that found in the Upper Cretaceous genus Hagenowinella Canu, 1900. There are usually four, sometimes six, distal spine-bases, arranged in pairs on either side of the small triangular avicularium. This avicularium is lacking on ovicelled zooecia. One of the Albatross specimens has the opercula, the ectocyst and part of the spines still preserved. This specimen is pink coloured with brownish opercula and spine-bases. The spines are long and tapering, hollow and simple, not bifurcate or cervicorn. The identification was checked by comparison with a specimen of C. patula from the Queen Charlotte Islands, 86.3.6.23, Hincks Collection, in the British Museum (Natural History) . Another species of Chaperia, with some reserve referred to C. cervicornis (Busk) , has been recorded from the Caribbean (Osburn, 1947, p. 15). According to Osburn this form has branched spines. Occurrence North-western Gulf: off Rio Grande 50 fathoms Cavalier 1956 Station 317 50 fathoms Cavalier 1956 Station 316 50 fathoms Cavalier 1956 Station 315 92 fathoms Cavalier 1956 Station 311 70 fathoms Cavalier 1956 Station 308 40 fathoms Cavalier 1956 Station 278 38 fathoms Cavalier 1956 Station 227 3T1h fathoms Cavalier 1956 Station 229 57 fathoms Cavalier 1956 Station 176 100 fathoms Eastern Gulf: Sandpile Bank 49 fathoms Atlantis 1951Stations153-155, 158-159 28-80 fathoms Vema-3 1954 Dredge #1, #2, BT#2 29-117 fathoms Additional occurrence 2 incrusting specimens, labelled "Chaperia galeata Busk" (U.S.N.M. Cat. No. 9769), from Sta. 104, near San Juan, Puerto Rico, 50 fathoms. Presumably this is Caroline 1933 Station 104, from 80-120 fathoms; see Bartsch, 1933, p. 29. Distribution Beaufort, North Carolina Gulf of Mexico 30 fathoms American Pacific coast from British Columbia to Lower California 0-47 fathoms Gulf of California 10-50 fathoms Fossil distribution Pleistocene of Santa Monica and Santa Barbara, California. Family ONYCHOCELLIDAE JULLIEN, 1882 Genus Floridina Jullien, 1882 Floridina parvicella Canu and Bassler (Pl. II, fig. 5) Floridina parvicella Canu and Bassler ( 1923, p. 57, pl. 31, fig. 12). Material Locality 76(3), 179(1), 354(3), 357(2), 358(1), 359(1), 360(10), 361(1), 36311), 365(7), 379(1), 388(1). Remarks Floridina parvicella rather closely resembles the type species, Flordina antiqua (Smitt). It differs, however, in its smaller dimensions and in the rounded tubercles which are constantly found at the junction of three zooecia. I doubt whether Canu and Bassler have observed tubercles in their Pliocene fossil, as no mention of these structures is made in the text. Their presence is suggested in the photograph of the type specimen. Dr. Richard S. Boardman, of the U.S. National Museum, has greatly obliged me by com­paring our figured specimen from Heald Bank with the type specimen (U.S.:\.M. Cat. No. 68477). Dr. Boardman states (in litt.): "your specimen of Floridina from Heald Bank appears . . . to be identical with F. parvicella. I checked against the holotype and the tubercles are equally developed. Also, this transparent, more massiw deposit is ex­tended along the boundaries between zooecia in several places in both colonies. I saw nothing to differentiate the two colonies into separate species." Avicularia are present in the figured specimen from Heald Bank. They are similar to those found inf. antiqua, but smaller. Hitherto only known as a Pliocene fossil from the U.S. Atlantic coastal plain, this species is surprisingly found living in the Gulf of Mexico today. Occurrence North-western Gulf: Heald Bank Dredge sample 81;3 fathoms Cavalier 1956 Station 227 37% fathoms Eastern Gulf: off Choctawhatchee Bay 12% fathoms off Panama City 11-16 fathoms off Cedar Keys 20, 64 fathoms Fossil distribution Pliocene (Waccamaw Marl) Waccamaw River, Horry County, South Carlonia. Family MICROPORIDAE GRAY, 1848 Genus Monoporella Hincks, 1881 Monoporella divae Marcus (Pl. II, figs. 3-4) Monoporella divae Marcus (1953, p. 286, pl. 2, figs. 26-27; pl. 3, fig. 28) . Material Locality 179 ( 5) . Occurrence North-western Gulf: Cavalier 1956 Station 227 371/z fathoms Distribution Espirito Santo, Brazil 35 meters Family SETOSELLIDAE LEVINSEN, 1909 Genus Setosella Hincks, 1877 Setosella vulnerata (Busk) (Pl. II, fig. 7) Membranipora vulnerata Busk (1860a, p. 124, pl. 25, fig. 3) . Setosella vulnerata Hincks ( 1877, p. 529), Hincks ( 1880a, p. 181, pl. 21, fig. 7 I, Hincks ( 1880b, p. 73, pl. 9, fig. 5), Jullien ( 1883, p. 524, pl. 17, fig. 66) , Cal wt 11907, p. 394), Levinsen (1909, p. 196), Waters (1925 p. 349, pl. 21, fig. 2), Marcus (1940, p. 155, text-fig. 83), Silen ( 1942, p. text-fig. 4, pl. 2, figs. 8-9). Material Locality 411(1) , 458(2), 458a(l). Remarks Setosella vulnerata (Busk) is one of the few species of Bryozoa which has been re­corded from a depth greater than 3000 metres (Silen, 1951, p. 68). Occurrence Eastern Gulf: Vema-3 1954 Dredge #1 117 fathoms Florida Straits: off Mollasses Reef Light 120-122 fathoms Distribution Shetland Islands 80-110 fathoms Bergen, Norway Skager Rack 200 metres Bay of Biscay 392, 1068, 1094 metres Portugal Mediterranean: off Marseilles, Nice, Capri, Algeria and Tunis Azores Josephine Bank, Atlantic 500-650 metres NW of Morocco 636 metres Funchal Bay, Madeira 30 fathoms Canary Islands 3700 metres Cape Verde Islands 460 metres N of Anguila, West Indies 170 fathoms Saint Barthelemy, West Indies 30-45 metres Gulf of Aden 30 metres Family CELLARIIDAE HINCKS, 1880 Genus Euginoma Jullien, 1883 Euginoma cavalieri sp. nov. (Pl. II, fig. 6) Holotype Locality 97: Cavalier 1956 Station 313. U.S.N.M. 648022. Paratypes Locality 349: Albatros 1885 Station D.2383. 7 specimens. U.S.N.M. 648023. Diagnosis Euginoma with the internodes consisting of 3n or 3n + 1 zooecia, with n varying between 2 and 6. Single median zooecia alternate with paired lateral zooecia, imparting a peculiar nodose aspect to each internode. Description Zoarium articulated. Internodes straight, each consisting of 3n or 3n + 1 zooecia, with n varying between 2 and 6; reaching a maximum length of 4 mm. Zooecia opening on the frontal side of the zoarium only; distinctly defined by thin raised margins; arranged in three longitudinal rows in alternating fashion. The zooecia which occupy the median row are single, those which make up the two lateral rows are paired. This arrangement results in a distinct bilateral symmetry and, simultaneously, in the nodose aspect of each internode. Opesia relatively large, semicircular, the proximal lip straight. Cryptocyst well-developed, finely granular, developed into a pronounced cryptocyst· ridge in the form of an oval horseshoe around the opesia with the two legs converging proximally. A large raised pore, facing proximally, is occasionally found at the base of the single median zooecium at the proximal end of an internode. Presumably this pore, and the small inflated chamber into which it leads, lodged the base of an anchoring filament or rootlet. Avicularia not observed. Ovicells entotoichal, opening through an independent transverse crescentic slit distally to the opesia. The few fertile zooecia ob­served all form part of the lateral rows. Dorsal side of internodes convex, finely granular, with thin raised sutures delineating the zooecial boundaries and with a small ringed median pore in the distal part of each single median zooecium. Measurements Holotype Lz=0.45mm lz =0.20mm ho =O.lOmm lo= 0.09mm Remarks According to Harmer (1926, p. 328) the genus Euginoma Jullien, 1883 is referable to the Aspidostomatidae, but I think it definitely belongs in the Cel!ariidae, as already im­plied by Jullien (1883, p. 520). The type species, Euginoma vermiformis Jullien is a deep water form from the Eastern Atlantic (Bay of Biscay; Canary Islands) with an established bathymetric range of 1094-3700 m. Euginoma cavalieri sp. nov. has the following features in common with the type species: 1) the shape and location of the opesia; 2) the development of a cryptocist-ridge around the opesia; 3) the location and character of the ovicell; 4) the absence of avicularia; 5) the finely granular aspect of the entire zoarium. It is also a deep water form (200-1181 fathoms). It differs from the type species in the peculiar arrangement of the zooecia, and in the relative size of the opesia. Occurrence North-western Gulf: Cavalier 1956 Station 313 Eastern Gulf: Albatross 1885 Station D.2383 200 fathoms 1181 fathoms Family BICELLARIELLIDAE LEVINSEN, 1909 Genus Beania Johnston, 1840 Beania hirtissima (Heller) (Pl. VIII, fig. 4) Diachoris hirtissima Heller ( 1867, p. 94, pl. 1, figs. 6-7). Beania hirtissima Waters (1918, p. 8, pl. I, fig. 2, cum syn.), Marcus (1937, p. 62, pl. 14, fig. 31), Osburn (1940, p. 397), Osburn (1950, p. 172, pl. 26, figs. 4-5), Gautier (1955, p. 243), Gautier (1957b, p. 103). Material Locality 444(2). Remarks Waters (1897, p. 17; 1918, p. 8) and Osburn (1950, p. 172) have indicated the number and arrangement of the distal and lateral spines. In this respect our two speci­mens compare very well with Mediterranean material of B. hirtissima in my possession, although on the whole their spines are more delicate and less differentiated as to size. Occurrence Eastern Gulf: SSW of John's Pass, Florida 34 fathoms Distribution Adriatic Mediterranean Madeira "on weeds between tide-marks" Cape Verde Islands 10 fathoms Bermuda Guanica Harbor, Puerto Rico Bay of Santos, Brazil 20 metres Port Culebra, Costa Rica 17 fathoms Secas Islands, Panama 25 fathoms Family SCRUPOCELLARIIDAE LEVINSEN, 1909 Genus Scrupocellaria Van Ben eden, 1845 Scrupocellaria harmeri Osburn (Pl. III, figs. 1-2) Scrupocellaria harmeri Osburn (1947, p. 20, pl. 3, figs. 1, 2), Osburn (1950, p. 138, pl. 18, figs. 9, 10; pl. 20, fig. 4). Material Locality 444(17). Remarks Among the species of Scrupocellaria with paired axillary vibracula and small, distally truncated scutum, S. harmeri resembles S. scupea Busk, but is a more delicate and slender species. Moreover, the opesia occupies less than half the frontal length of the zooecia in S. harmeri, whereas the reverse is true in S. scrupea. Occurrence Eastern Gulf: SSW of John's Pass, Florida 34fathoms Distribution Aruba 23-24 fathoms Galapagos 32 fathoms Santa Catalina Island, California 2-3 fathoms La Jolla, California "among algae" Genus Caberea Lamouroux, 1816 Caberea boryi (Audouin) (Pl. III, figs. 3-4) Crisia boryi Audouin (1826, p. 242), Savigny (pl. 12, fig. 4). Caberea boryi Harmer (1926, p. 362, pl. 24, figs. 13-15), Marcus (194la, p. 46, pl. 1, figs. 3A-B), Hastings ( 1943, p. 367, text-figs. 19A-B, cum syn.) , Osburn ( 1950, p. 129, pl. 15, figs. 4-6). Material Locality 88 ( 10), 99(9), 101 ( 1), 444(3). Remarks The tapering distal lobe of the scutum is fused to a complete calcareous bar which spans the opesia below the orifice. According to Hastings ( 1943, p. 365) , this condition is typical for representatives of the Caberea boryi group. The rounded proximal lobe of the scutum, practically flush with the opesial border, completely fills the opesia with the exception of a narrow crescentic slit. Osburn (1950, p. 129) definitely observed the bar in Californian specimens, believing it to be part of the scutum. His figures ( l.c., pl. 15, figs. 4, 6), however, are obviously incomplete in as much as the artist has left out the structure altogether. Occurrence North-western Gulf: Cavalier 1956 Station 322 23 fathoms Cavalier 1956 Station 311 70 fathoms Cavalier 1956 Station 309 57 fathoms Eastern Gulf: SSW of John's Pass, Florida 34 fathoms American distribution Bay of Santos, Brazil Anacapa Passage, Southern California 15-50 fathoms Cedros Island, Lower California 10-15 fathoms Guadalupe Island, Lower California 17 fathoms Gulf of California Family CRIBRILINIDAE HINCKS, 1879 Genus Figularia Jullien, 1886 Figularia contraria sp. nov. (Pl. IV, fig. l; Pl. VIII, fig. 5) Holotype Locality 69. USNM 648027. 70 mi. SE of Freeport, Texas. Approximately 30 fath­oms. 1 specimen (and 2 fragments) originally encrusting a smooth, rounded, fist­size cobble. This distance and direction locate the sample in the immediate vicinity of Stetson Bank (Lat. 28°9'48" N, Long. 94°17'42" W), which is well compatible with the presence of a cobble. Stetson Bank owes its presence to an underlying salt diapyr which has caused older, indurated sedimentary rocks to crop out on the Gulf bottom at this locality. Pebbles and rock fragments dredged from Stetson Bank have been described by Ewing and Ericson (1954) and by Neumann (1958). Diagnosis Figularia with the frontal shield of the fertile zooecia consisting of 5-7, that of the sterile zooecia consisting of 8-11 (mostly 9) costae. Orifice distinctly smaller in the ovicelled zooecia. Description Zoarium encrusting. Zooecia irregularly hexagonal, strongly variable in size and shape, distinctly defined by shallow grooves. Gymnocyst forming a continuous zone of variable width between the zooecial margins and the frontal shield, and bearing a num­ber of concentric growth-striae which are particularly well apparent proximally. Frontal shield of variable size, slightly raised above the level of the gymnocyst, consisting of 5-7 costae in the ovicelled zooecia and of 8-11 (mostly 9) costae in the sterile zooecia. The costae are fused in the median line and the distal pair forms the apertural bar. The intercostal space is subdivided by secondary fusion. The resulting six rounded lacunae between adjacent pairs of costae decrease in :ize towards the centre of the frontal shield, and the two smallest, central lacunae often coalesce to form one single, larger pore. A small, slightly raised, pelma is found at the lateral end of each costa. Orifice with a broad shallow sinus and a pair of minute lateral condyles; distinctly smaller in the ovicelled zooecia. Avicularia not observed, presumably rare. Ovicells large, galeate, occupying al­most the entire distal half of the fertile zooecia, with a distinct median frontal carina. The ovicells are perforated and the following arrangement of pores (fenestrae) seems to prevail: 1) a pair of small frontal fenestrae directly adjacent to the carina; 2) a pair of slightly larger, lateral fenestrae at the same height; 3) a median group of several pores on the distal slope. This arrangement is not clearly brought out in the figure. (Pl. IV, fig. 1). Measurements sterile fertile Lz = 0.57-0.87 mm Lz = 0.55-0. 72 mm lz = 0.32-0.45 mm lz = 0.30-0.40 mm ha =0.15mm ha= 0.07-0.09 mm la =0.15mm la= 0.12-0.14 mm Remarks None of the four Recent American species of Figularia described to date, F. magel­lanica (Calvet), F. patagonica (Waters), both from the Magellan region, F. ampla (Canu and Bassler), from Havana, Cuba and F. hilli (Osburn), from California, is directly com­parable with the present species. The striking feature in this species is that, contrary to what is normally seen in Figularia, the orifices of the ovicelled zooecia are smaller than those of the sterile zooecia. Occurrence North-western Gulf: Stetson Bank area approx. 30 fathoms Bellulopora gen. nov. Colletosia (partim) Osburn ( 1950, non Colletosia Jullien, 1886 = Umbonula Hincks, 1880). Type species Colletosia bellula Osburn, 1950, p. 188, pl. 29, fig. l. Recent: Galapagos Islands and Gulf of California; Pleistocene: Newport Harbor Mesa, Southern California. Diagnosis lncrusting Cribrimorph with a keyhole-shaped ( cleithridiate) orifice, flanked by a pair of small, adventitious, pedicellate avicularia. Ovicell hyperstomial, the ectooe­cium consisting of radiating costate, separated by rows of lacunae. Remarks The necessity of introducing a new genus is explained under B. bellula (see below) . Bellulopora bellula (Osburn) (Pl. IV, fig. 2) Colletosia bellula Osburn (1950, p. 188, pl. 29, fig. l), Soule (1959, p. 49). Material Locality 179(1), 383(1). Remarks Osborn (1950, p. 189) referred this form to Jullien's genus Colletosia because he considered it to be congeneric with Collestosia radiata (Moll). Recently, Bobies (1956, p. 244) has shown that Colletosia Jullien, 1886 is not a Cribrimorph genus at all, but a synonym of the Ascophoran genus Umbonula Hincks, 1880. See also Brown, 1958, p. 54. Eschara radiata Moll is the genolectotypte (selected by Canu and Bassler, 1929, p. 33) of Cribrilaria Canu and Bassler, 1928. This well-known species has a small, semicurcular orifice and relatively large, lanceolate, vicarious avicularia, which occur scattered throughout the zoarium or may be absent altogether. It is difficult to see how this species could possibly be congeneric with "Colletosia" bellula. "Colletosia" bellula Osburn has a keyhole-shaped ( cleithridiate) orifice, flanked by a pair of small, adventitious, pedicellate avicularia, which are very constant in their presence. This condition is unique among the known Recent Cribrimorphs and necessi· tates the introduction of a new genus, for which the name Bellulopora is proposed. The cleithridiate orifice with a small avicularium on either side is reminiscent of condi­tions obtaining in certain extinct Cribrimorph genera, e.g. Plwphloea Gabb and Horn, 1862 (Upper Cretaceous-Paleocene). The avicularia in Pliophloea, however, are vi· carious, not adventitious, and the ovicell is distinctly carinate, not costate. Occurrence North-western Gulf: Cavalier 1956 Station 227 Eastern Gulf: Atlantis 1951 Station 158 37% fathoms 33 fathoms Distribution Galapagos Islands Gulf of California 5~0fathoms 14-40 fathoms Fossil distribution Pleistocene of Newport Harbor Mesa, Southern California. Family CHORIZOPORIDAE HARMER, 1957 Genus Chorizopora Hincks, 1879 New Additions to the Bryozoan Fauna of the Gulf of Mexico Chorizopora brongnwrtii (Audouin) (Pl. IV, fig. 5) Flustra brongnwrtii Audouin ( 1826, p. 240), Savigny (pl. 10, fig. 6). Chorizopora brongniarti Canu and Bassler (1930, p. 14), Osburn (1952, p. 279), Harmer (1957, p. 948, text-fig. 99, pl. 73, figs. 19, 20, cum syn.). Material Locality 395 ( 1). Remarks There is only one previous record of this species from the Americas, referring to a single colony from the Galapagos Islands. Occurrence Eastern Gulf: Atlantis 1951 Station 170 11 fathoms American distribution Galapagos Islands 40 fathoms Family HIPPOPODINIDAE LEVINSEN, 1909 Genus Hippopodina Levinsen, 1909 Hippopodina bernardi sp. nov. (Pl. IV, figs. 3-4) Holotype Locality 99 (fragment the size of one zooecium). U.S.N.M. 648030. Paratypes Locality99(6). U.S.N.M.648031 (figured),648032. Other material Locality 94(3). Diagnosis Hippopodina with one long, acuminate, proximally directed frontal avicularium and with two rows of marginal pores around a large, granular, imperforate pectoral area. Description Zoarium encrusting. Zooecia moderately large, distinctly defined by a slightly raised margin flanked on either side by rows of marginal pores. Orifice subcircular, divided by a pair of minute lateral condyles in a large porta and a wide and shallow concave vanna. Peristome only laterally raised, slightly cusped distally on either side. Frontal wall broadly convex, with a large, granular, imperforate pectoral area, surrounded by two rows of marginal pores. Avicularia single, proximally to the orifice, the long acuminate rostrum proximally directed, cutting obliquely across the pectoral area. Ovicells large, hyperstomial, flattened in front, finely and evenly perforate. New Additions to the Bryozoan Fauna of the Gulf of Mexico Measurements Holotype Lz =0.87mm lz = 0.62 mm ho= 0.19mm lo= 0.18 mm Remarks Hippopodina pectoralis Harmer (1957, p. 976, pl. 67, figs. 6, 10, 11), a related deep water species from the Celebes Sea, is slightly larger and has three rows of marginal pores and no avicularia. Another allied species appears to have been figured as Codonellina cribriformis /c; and 23 fathoms on the Florida shelf. L. uvulifera was originally recorded from the Tortugas, Florida, some 175 nautical miles further south, at 10 fathoms. A final verdict clearly hinges on a re­appraisal of Osburn's single type specimen. Occurrence North western Gulf: Heald Bank Dredge sample 81/s fathoms Cavalier 1956 Station 331 6% fathoms Cavalier 1956 Station 329 6 fathomas Cavalier 1956 Station 291 4 fathoms Cavalier 1956 Station 179 37% fathoms Eastern Gulf: numerous stations 55/6-23 fathoms Distribution Bay of Santos, Brazil 0-20 metres St. Helena 36-39 metres Jicaron Island, Taboga, Coiba, Panama 0-12 fathoms Gorgona, Colombia 0-15 fathoms Galapagos Islands 0-15 fathoms American Pacific coast from Southern California to the Galapagos Islands 0-82 fathoms Genus Hippodiplosia Canu, 1916 Hippodiplosia americana (Verrill) (PL V, fig. 4) Lepralia americana Verrill (1875, p. 415, pl. 7, fig. 4, non fig. 5 = Cryptosula pallasiana Moll sp.), Osburn (1912, p. 241, pl. 25, figs. 55, 55a, cum syn.). Hippodiplosia americana Hastings (1930, p. 725, pl. 11, fig. 61) , Osburn (1933, p. 40, pl. 14, figs. 6, 7), Marcus (1937, p. 101, pl. 20, figs. 54A, B), Osburn (1952, p. 339, pl. 40, fig. 4), Maturo ( 1957, p. 51, text-fig. 56). Material Locality 4(1), 5(8), 14(1). Remarks The North American distribution of this species resembles that of the hydroid Tubu. Zaria crocea (Agassiz) (see Deevey, 1950, text-fig. 3) in that it provides another example of discontinuous distribution around the Florida Peninsula (Fig. 3). Disjunct distribu· ti on patterns of this type have been attributed by Deevey ( l. c.) to the existence of a thermal barrier which would prohibit the dispersal of boreal Atlantic species around the Peninsula. According to Deevey, the hydroid Tubularia crocea-and this might apply as well to the bryozoan Hippodiplosia americana-"is to be regarded as a relict of a glacial age of the Pleistocene, when free migration of boreal species from the Atlantic to the Gulf coast was entirely practical." However, the validity of this hypothesis, with its strong accent on temperature as the controlling factor, is seriously impaired by the known occurrences of T. crocea at Panama and the Galapagos Islands, and by the occurrences of H. americana at these two localities, as well as at Santos, Brazil and in the Gulf of Cali­fornia. These records from subtropical or tropical regions cannot be explained away by simply promoting the tropical form to the rank of "physiological subspecies," morpho· logically identical with, but physiologically different from the boreal species (Deevey, l. c., p. 356) . Hedgpeth, in his illuminating paper on the Zoogeography of the Northwestern Gulf of Mexico (1953), has shown (l. c., p. 199-200) that disjunct distribution is by no means rare among several groups of marine organisms recorded from Texas and Louisiana, and not necessarily limited to temperate species. Furthermore, Hedgpeth has somewhat re­duced the unequal appraisal of salinity with respect to temperature as a factor controlling disjunct distribution, stating (l. c., p. 203): "Other species may be absent from south Florida because suitable estuarine (i.e. euryhaline) conditions are lacking." In my opinion a simple explanation for the absence from Florida and the North-eastern -~---i---:, _--?; -­ D1slribu'1on of H1ppodlplo1io omericono (Verrell)Oistr1bulion of Electro mono1tod1ys ( Busk ) FIG. 3. Examples of disjunct distribution of Bryozoan species along the American Atlantic and Gulf coasts. New Additions to the Bryozoan Fauna of the Gulf of Mexico Gulf of the two disjunct bryozoan species Hippodiplosia americana and Electra mono­ stachys is to be found in the coordination of the following facts: 1) around the southern half of the Florida Peninsula salinities, even those of the very shallow inshore waters, are high (in the order of 36%0 or more) and remarkably con­stant throughout the year; cf. data for Fowey Rocks, presented by Dole and Chambers (1918), and graphs illustrating "hydrographic climate" at Key West by Hedgpeth (l. c., p.145). 2) In the Northwestern Gulf H. americana and E. monostachys occur only in those in· shore and very shallow offshore waters whose monthly' average salinity remains gen­erally < 30 %o throughout the year: Corpus Christi Bay, Aransas Bay, San Luis Pass, Galwston Island, and off the mouth of the Brazos River. In other words, the disjunct Bryozoa are typically brackish (polyhaline) species. It is an established fact that several other invertebrate species which have been cited as typical examples of disjunct Atlantic-Gulf distribution, such as the marsh crab Sesarma reticulatum, the salt marsh periwinkle Littorina irrorata, the American oyster Crassostrea virginica and several other pelecypods, e.g., Abra aequalis, Rangia cuneata, and Poly­mesoda caroliniana, all inhabit low salinity biotopes. It seems, therefore, that the barrier to free dispersal around the Florida Peninsula is of a saline rather than a thermal nature. This view does not invalidate Deevey's glacial relict hypothesis. On the contrary, the possibility that some of the disjunct species in the NW Gulf are true glacial relicts in Deevey's sense is real, distribution having been continuous during interglacial periods when Florida was submerged and the polyhaline inshore wa· ters of the Northern Gulf merged with those extending along the Atlantic coast of Georgia and the Carolinas. Occurrence North-western Gulf: Corpus Christi Bay, Texas Mud Island, Aransas Bay, Texas %-% fathom %-1 fathom Distribution North American Atlantic coast from Mt. Desert Island. Maine. to Beaufort, North Carolina Bay qf Santos, Brazil Balboa, Panama Canal Zone Agua Verde Bay, Gulf of California } Port Culebra, Costa Rica Galapagos 20 metres buoy 10-30 fathoms Family EXOCHELLIDAE BROWN, 1952 Genus Exochella Jullien, 1888 Exochella "longirostris Jullien (PL V, fig. 5) M ucronella tricuspis Hincks: Busk ( 1884, p. 159, pl. 22, fig. 3, non M ucronella tricuspis Hincks, 188 lb, p. 125, pl. 3, fig. 1). Exochella longirostris Jullien (1888, p. 55, pl. 3, figs. 1-4; pl. 9, fig. 2), Calvet (1904, p. 29), Marcus (1937, p. 82, pl. 17, fig. 43, cum syn.), Marcus (194lb, p. 22, fig. New Additions to the Bryozoan Fauna of the Gulf of Mexico 16), Marcus (1949, p. 1), Mawatari (1952, p. 265) , Rogick (1956, p. 123, figs. lA-J). Material Locality 99 ( 3) . Remarks Complete coalescence of the proximal bifid median denticle with the pair of lateral teeth in the secondary orifice, resulting in two independent rounded pores or tubes, has been described from Exochella tricuspis Hincks sp. (Waters, 1906, p. 20; Levinsen, 1909, p. 320) and also from Exochella longirostris Jullien (Waters, 1889, p. 15; Waters, 1906, p. 20). In E. tricuspis, however, the areolar pores are often difficult to observe and the avicularia are very consistent in their paired occurrence and lateral orientation (e.g., the lectotype -specimen, 99.5.1.883, from Curtis Island, Bass Straits; or 97.5.1.918, from Western Port, Victoria). In E. longirostris the marginal areolae are very conspicuous even in the young zooecia and separated by projecting ribs in the older ones and the avicularia are often single and sometimes entirely absent and they are not quite as regu­larly arranged. In these characters the Gulf specimens definitely resemble E. longirostris. Matters are complicated by the fact that Busk's figured specimen (87.12.9.635, from Prince Edward Island) and another Challenger specimen (87.12.9.637, from Challenger Station 315) are not identical with E. tricuspis (Hincks), although they were identified as such (Busk, 1884, p. 159, pl. 22, fig. 3). Their morphological characters point to E. longirostris Jullien. This view is supported by the following facts: 1) Although Busk (1884, p. ix) identified the only Mucronella among the 15 species of Bryozoa from Challenger Station 315 as Mucronella tricuspis Hincks, Levinsen ( 1909, p. 321, pl. 17, figs. 6a, b) described and figured "A small colony from the Challenger St. 315" as Exochella longirostris Jullien. 2) A slide bearing a specimen from West Point Island, West Falklands (30.1.16.12) is labelled "Mucronella tricuspis Busk Chall. XXX p. 159 not Hincks" in Dr. A. B. Hast­ings' handwriting. This and another specimen from Cape Orford, Port Stephens, West Falklands (30.1.16.5) are probably the "Recent specimens of E. longirostris Jullien from the Falkland Islands in the Zoological Department collections" referred to by Brown ( 1952, p. 289) as giving evidence for the umbonuloid structure of the frontal wall in Exochella. The occurrence of E. longirostris in the NW Gulf of Mexico is rather unexpected, as the known distribution of this species was hitherto limited to the Southern Hemisphere, S of the 20° parallel, with the exception of one record from Japan. Occurrence North-western Gulf: Cavalier 1956 Station 311 70 fathoms Distributwn Magellan Region 19 metres Falkland Islands 12 metres Chatham Islands Prince Edward Island 80-150 fathoms Cape of Good Hope New Additions w the Bryozoan Fauna of the Gulf of Mexico Bay of Santos, Brazil down to 20 metres Santa Catharina Island, Brazil Guaratuba, Brazil Espirito Santo, S of Victoria, Brazil 35 metres Marguerite Bay, Antartica 85-100 fathoms Kii Peninsula, Japan Fossil distribution Post-Pampean (Holocene), Puerto Militar, Bahia Blanca, Argentine. Family SMITTINIDAE LEVINSEN, 1909 Genus Smitwidea Osburn, 1952 Smittoidea reticulata (Macgillivray) (Pl. VI, fig. 1) lepralia reticulata Macgillivray ( 1842, p. 467). American records: non Smittia reticulata Robertson ( 1908, p. 306, pl. 23, figs. 75, 76 = Smitwidea prolifica Osburn). Smittina reticulata Canu and Bassler (1930, p. 27). Smittoidea reticulata Osburn (1952, p. 409, pL 48 figs. 9, 10), Soule (1961, p. 34). Material Locality 99(5). Remarks Our specimens have been compared with ovicelled British specimens of S. reticulata (e.g., 99.5.1.916, Britain, Hincks Collection). Except for the occasional presence of two spine bases in the distal gap of the peristome in the latter, the similarity is perfect. Previous American records of S. reticulata are from the Galapagos Islands, from the Gulf of California, and from the Falkland Islands. Occurrence North-western Gulf: Cavalier 1956 Station 311 70 fathoms American distribution Galapagos Islands Gulf of California } 17-150 fathoms Falkland Islands Genus Codonellina Bassler, 1934 Codonellina montferrandii (Audouin) (Pl. VI, fig. 3) Flustra montferrandii Audouin ( 1826, p. 240) , Savigny (pl. 9, fig. 14). Codonellina anatina (Canu and Bassler) Osburn (1952, p. 422, pl. 46, figs. 14, 15). Codonellina montferrandii Harmer (1957, p. 1049, pl. 69, figs. 25, 26, 30, cum syn.). Material Locality 94 ( 15). New Additions to the Bryozoan Fauna of the Gulf of Mexico Remarks This species has its main distribution in the tropical Indo-Pacific, where it is widely distributed: Red Sea, Ceylon, Wasin (British East Africa), Malay Archipelago, Philip­pines, Japan, Australia, Hawaii, Galapagos Islands, Gulf of California. Osburn (1952, p. 422) indicates the presence of spathulate avicularia in his specimens of C. anatina from the Gulf of Mexico, but it is obvious that this was a slip of the pen since he was discussing material from the Gulf of California. Occurrence North-western Gulf: Cavalier 1956 Station 316 50 fathoms American distribution Galapagos Islands Gulf of California 0-40 fathoms Genus Parasmittina Osburn, 1952 Parasmittina signata (Waters) (Pl. VI, fig. 2) Smittiasignata Waters (1889, p.17, pl. 3, figs. 4-6). Schizopodrella horsti Osburn (1927, p. 127, text-figs. 3-5). Schizoporella horsti (Osburn) Marcus (1937, p. 87, pl. 18, fig. 46), Marcus (1939, p. 139, pl. 9, fig. 13) -Lacerna horstii (Osburn) Osburn (1940, p. 426) , Osburn (1947, p. 31). Smittina signata Harmer (1957, p. 928, pl. 63, figs. 27-29, cum syn.). Material Locality 23(1) , 76(1), 94(1) , 99(1) , 113(1), 145(29), 179(1), 354(1), 380(1) , 382 ( 1)' 384(2)' 388 (2)' 389( 1)' 390(2)' 416 ( 1)' 424( 1)' 426 ( 4)' 428 (1). Remarks Parasmittina signata (Waters), originally described from Port Jackson, New South Wales, has a wide distribution in the Indian Ocean and Western Pacific. The identity of our Gulf specimens has been established by direct comparison with Australian speci­mens in the collections of the Zoological Department of the British Museum (N.H.): 34.11.12.65, a Challenger specimen from Australia?, and 32.4.20.51, from the Great Barrier Reef. The discovery of this species in the Gulf of Mexico leads further support to Harmer's tentative suggestion ( 1957, p. 930), that Schizopodrella horsti Osburn, from the Caribbean and Brazil, is a synonym of Parasmittina signata. Occurrence North-western Gulf: Cavalier 1956 Station 12 81h fathoms Heald Bank Dredge sample 81h fathoms Cavalier 1956 Station 316 50 fathoms Cavalier 1956 Station 311 70 fathoms Cavalier 1956 Station 297 9 fathoms Cavalier 1956 Station 273 24fathoms Cavalier 1956 Station 227 371h fathoms New Additions to the Bryozoan Fauna of the Gulf of Mexico Eastern Gulf: off Choctawhatchee Bay 12¥2 fathoms off Cedar Keys 17-43 fathoms Lower Tampa Bay-Egmont Channel 6-7 fathoms off Egmont Key 10¥2 fathoms Distribution Suez Indian Ocean 125 fathoms Malay Archipelago 0-275 metres Philippines 186-530 fathoms Japan Great Barrier Reef 131/2 fathoms New South Wales Adelaide 20-35 fathoms Tahiti Cura<;ao } Colombia 17-23 fathoms Venezuela Puerto Rico 5-8 fathoms Bay of Santos, Brazil 0-20metres Genus Phoceana Jullien, 1903 Phoceana acadiana sp. nov. (Pl. VI, fig. 7) Holotype Locality 469 (large specimen, measuring 9.7 mm in length) . USNM 648044. Paratypes Locality 412 ( 4). USNM 648045 (figured), 648046. Locality 469(3). USNM 648047. Other material Locality 458 ( 18), 461 (1). Diagnosis Phoceana with the zooecia arranged in four longitudinal rows throughout the zoarium. Peristome long and tapering, making an acute angle with the zoarial branch, its rim not everted or thickened. Interior wall of peristome smooth, without proximal ridge. Description Zoarium erect, consisting of a long, slender stem which gives off occasional branches at almost right angles. Zooecia alternating in four longitudinal rows throughout the zoarium, well defined exteriorly by distinct sutures. Primary orifice invisible from the outside. Secondary orifice sub-circular. Peristome long and tapering when complete, making an acute angle with the zoarial branch, its rim not everted or thickened. Frontal wall an olocyst, covered by a white tremocyst, and bordered by a small number of mar­ New Additions to the Bryozoan Fauna of the Gulf of Mexico ginal pores. Avicularia lacking. Ovicells hyperstomial, globular, lodged in the acute angle between the peristome and the outer wall of the zoarial branch. Measurements Holotype Figured paratype Lz = 0.90 -1.10 mm Lz = 1.-mm lz = 0.45mm lz = 0.45mm diameter of secondary orifice= 0.12 -0.15 mm = 0.15mm Remarks The four Oregon specimens stand out by their fine preservation and by the possession of ovicells. The largest zoarial fragment .measures 9.7 mm. The peristomes are consid­erably more produced than in the Verna specimens and are almost transparent. Several of the amber-coloured opercula are still in situ. The frontal is an olocyst, with irregular patehes of white tremocyst preserved in the Verna specimens. The specimens taken off Molasses Reef Light, although badly altered, are interesting because they show the mode of branching which occurs almost at right angles to the main branch. The diagnosis given above summarizes those characters which distinguish this species from Phoceana columnaris Jullien, the type species (by .monotypy) of Phoceana Jullien, 1903, itself a deeper water species (100---445 m) from the Eastern Atlantic and the Western Mediterranean. I have compared my specimens with a Mediterranean specimen of P. columnaris (St. 1292, SW of Alboran Island, 100-115 m), which Dr. Y. V. Gautier (Marseilles) has kindly made available. Occurrence Eastern Gulf: Vema-3 1954 Station BT #2 96 fathoms Florida Straits: off Molasses Reef Light 122 fathoms off Carysfort Light 78 fathoms NW of Cay Sal Bank 150 fathoms Family LEKYTHOPORIDAE LEVINSEN, 1909 Genus Lekythopora MacGillivray, 1883 Lekythopora longicollis sp. nov. (Pl. VI, figs. 4--5) Holotype Locality 99 (cluster of six zooecia, one with ovicell). USNM 648048. Paratypes Locality 99 ( 8) . l"SNM 648049 (figured), 648050. Other material Locality 68(1), 69(1), 70(2), 72(1), 94(3), 150(2), 444(2). Description Zoarium presumably encrusting a perishable substratum. Zooecia small, flask-shaped, in small clusters of 3-9 zooecia. Frontal wall convex, evenly but not very densely perfo­ New Additions to the Bryozoan Fauna of the Gulf of Mexico rated by rather coarse tremopores, not verrucose. Peristome smooth, long and slender and hardly flaring distally. The volume of the peristome of a fully produced peristome is only slightly less than that of the adnate part of the zooecium. The change from the porous tremocyst to the smooth peristome is abrupt and the peristome is often somewhat constricted at this point. A pair of minute, acute, triangular avicularia is inserted in the lateral rim of the peristome, but they are not always easy to observe. They extend down­wards along the peristomial wall as long and narrow tubular chambers. The ovicells are small, perched high above the base of the peristome, and have a large crescentic densely porous frontal area. Measurements Holotype and paratypes Lz (incl. peristome) = 0.40-0.58 mm (sterile zooecia) Lz (incl. peristome) = 0.62-0.70 mm (fertile zooecia) lz = 0.18-0.30 mm ho (second. orifice) = 0.08-0.12 mm lo (second. orifice) = 0.08-0.12 mm Remarks This appears to be a fairly common species in the North-western Gulf of Mexico. Among the American species of 'lagenipora' the new species resembles 'l.' marginata Canu and Bassler (1930, p. 36, pl. 6, figs. 2, 3), from the Galapagos Islands, in several ways. As ascertained on the three topotypes of 'l.' marginata in the collections of the Zoological Department, British Museum (N. H.) , 33.12.10.16, from Albatross Station D.2813, 40 fathoms, the latter is a larger species, however, with a more densely perforated tremocyst and with the ovicell "always fixed at the base of the peristome." Occurrence North-western Gulf: Vema-3 1954 Core #65 30 fathoms vicinity of Stetson Bank approx. 30 fathoms Univ. of Houston sample 15 29 fathoms Univ. of Houston sample 12 311/3 fathoms Cavalier 1956 Station 316 50 fathoms Cavalier 1956 Station 311 70 fathoms Cavalier 1956 Station 278 38 fathoms Eastern Gulf: SSW of John's Pass, Florida 34 fathoms Family CREPIDACANTHIDAE LEVINSEN, 1909 Genus Crepidacantha Levinsen, 1909 Crepidacantha poissonii (Audouin) var. teres Hincks (Pl. VI, fig. 6) lepralia kirchenpaueri Heller var. teres Hincks ( 1880b, p. 77, pl. 9, figs. 7, 7a). Crepidacantha poissonii var. teres Brown (1954, p. 247, text-figs. IA, B, cum syn.). American records: Crepidacantha poissonii Canu and Bassler (1928a, p. 136, pl. 34, fig. 3), Canu and Bas­ sler (1930, p. 33, non pl. 5, fig. 5 = Crepidacantha solea Canu and Bassler). Crepidacantha poissoni Osburn ( 1940, p. 451), Osburn ( 1952, p. 4 78, pl. 58, fig. 2) . Material Locality99(1), 101(1), 179(2). Remarks Our specimens compare in every detail with specimens from Madeira in the Norman Collection: 11.10.1.783, 784, 785, which belong to this variety (fide Brown, 1954, p. 247). As pointed out by Canu and Bassler (1928, p. 136, 137; 1930, p. 33), the paired vi­bracula are often placed asymmetrically on the frontal wall. This arrangement is also apparent in our Gulf specimens, as well as in the specimens from Madeira referred to above. Moreover, one of the vibracula is often somewhat larger than the other of the same pair, as is well shown in Osburn's figure ( 1952, pl. 58, fig. 2). I depart slightly from Brown's recent review of the genus in including the material from the Galapagos Islands, identified by Canu and Bassler ( 1930, p. 33) as C. poissonii, as well as Osburn's material of C. poissoni from the American Pacific coast, in the present variety rather than in Crepidacantha solea Canu and Bassler (cf. Brown, 1954, p. 253). In C. poissonii var. tres the proximal lip of the orifice is straight or only slightly convex, and Osburn (1952, p. 478) describes this feature in his American Pacific coastal speci­mens as "straight." In C. solea, a species originally described from the China Sea, the proximal lip of the orifice is distinctly produced (and "square, plate-like"), which affects the entire shape of the orifice. On this character the specimen from Hawaii figured as C. poissonii by Canu and Bassler ( 1928b, pl. 8, fig. 7; 1930, pl. 5, fig. 5) might well re­ main in C. solea where Brown placed it. Occurrence North-western Gulf: Cavalier 1956 Station 311 Cavalier 1956 Station 309 Cavalier 1956 Station 227 70 fathoms 57 fathoms 37% fathoms Distribution Funchal Bay, Madeira Cape Verde Islands Bermuda Puerto Rico Galapagos Islands Pacific coast of America between Santa Barbara Island, off Southern California, and La Libertad, Ecuador } 30 fathoms 110-180 metres 6 fathoms 33%-40 fathoms 0-73 fathoms Fossil distribution Pliocene of Bocas Island, Almirante Bay, Panama. Family VITTATICELLIDAE HARMER, 1957 Genus Vittaticella Maplestone, 1901 V ittaticella uberrima Harmer (Pl. VII, figs. 1-2.) ?Vittaticella elegans (Busk) Osburn (1940, p. 464, pl. 9, figs. 78, 79, non Catenicella elegans Busk, 1852, p. 361, pl. 1, fig. 2). Vittaticella uberrima Harmer (1957, p. 772, pl. 50, figs. 4, 5, 15, cum syn. ). Material Locality 111 ( 10). Remarks Although the few isolated internodes from Cavalier 1956 Station 299 in the North­western Gulf of Mexico do not consist of more than two zooecia each, and although g~ gantic avicularia of the type described by Harmer have not been found, comparison with Harmer's Siboga material leaves me satisfied that the Gulf specimens belong to V. uber­rima. The zooecia are long and slender, the vittae are lateral, the ovicell features a single row of pores around the distal margin of the entooecium, and the lateral processes are not cusped distally, but transverse. With regard to Vittaticella elegans (Busk) Harmer (1957, p. 770) has stated "V. elegans occurs commonly on the southern coast of Australia and off New Zealand; ex­tending at least as far north as New South Wales. I have no evidence that it reaches tropi· cal waters; and various records of this species outside the area above indicated may be disregarded." This also affects the American records of V. elegans (Busk, 1884, p. 12; Correa, 1947, p. 1; Osburn, 1940, p. 464; 1952, p. 286). As Osburn (1940, p. 464) observed giant avicularia with a long spathulate mandible in Puerto Rican specimens of "V. elegans," there is reason to believe that they also belong to V. uberrima, the position of the adzooecial vittae in Osburn's pl. 9, fig. 78 probably being inaccurate. Occurrence North-western Gulf: Cavalier 1956 Station 299 111/6 fathoms Distribution Australia Malay Archipelago Zanzibar ? Algoa Bay, South Africa ?Ceylon ? Puerto Rico 0-88 metres 0-10 fathoms 5-30 fathoms Family SA VIGNYELLIDAE LEVINSEN, 1909 Genus Halysisis Norman, 1909 Halysisis diaphana (Busk) (Pl. VII, fig. 3) Scruparia diaphana Busk ( 1860b, p. 281, pl. 31, fig. 1). Halysisis diaphana Harmer (1957, p. 764, pl. 51, fig. 22, cum srn.). Material Locality 382 (2), 389 ( 1), 390 (1). Remarks The ovicell, with the two large frontal pores, was first described and figured by Waters (1913). Two of our fragmentary specimens include part of an ovicelled zooecium, but unfortunately in each case the frontal part of the ovicell is broken off. Occurrence Eastern Gulf: Atlantis 1951Stations157, 164, 165 17, 34 fathoms Distribution Madeira no depth given Cape Verde Islands 52-219 metres St. Paul's Rocks (Challenger Station 109) shallow water Zanzibar 8-10 fathoms Malay Archipelago 0-45 metres ?Japan 30-35 fathoms lncertae sedis Genus Fedora Jullien, 1883 Fedora nodosa Silen (Pl. VIL figs. 4--5) Fedora nodosa Silen (1947, p. 53, text-figs. 41-45, pl. 4, figs. 22, 23). Material Locality 68(2, 72(1), 93(10), 94(8), 99(1), 101(4), 102(13), 103(3), 104(7), 150(30), 177(1), 178(1), 179(8), 181(8) , 332(21), 351(1), 368(17), 369(24), 377 (7)' 378 (3), 379(6)' 380(9), 381 (2)' 382 ( 14)' 383 ( 5)' 384(2)' 385 ( 1) ' 386(19),411(4),412(12).443(1) , 458(15),458a(2),464(3). Remarks This is clearly one of the more common species in the Gulf of Mexico and it is re­markable that it should have escaped the attention of earlier workers until Silen even­tually described it in 1947. In order to facilitate a more detailed discussion of this interesting species, our Gulf specimens may be conveniently arranged in four categories: A. Small, juvenile colonies consisting of three to approximately eight zooecia. They are usually "free," but incrusting specimens are found occasionally (Cavalier 1956 Sta­tions 278, 316; Atlantis 1951Station158; Vema-3 1954 Dredge # 1). B. Larger, incrusting zoaria, generally growing on and around small foreign calcareous objects, and tending to attain an ovoid or spindle shape with advancing growth. Al­most complete incorporation of the small object into the axial part of the semi-ovoid or hemispherical colony is seen in specimens from the following samples: Vema-3 1954 BT #2, off Mola~ses Reef Light and Cavalier 1956 Station 278, from 96, 122 and 38 fathoms, resp. C. Larger, semi-ovoid or hemispherical colonies with exposed axial cavity. In some colonies this cavity is wide open, in others it is narrow, but its shape is always irregu­lar and its wall hummocky and uneven. In these zoaria there is nothing to suggest incrustation on solid objects. One could visualise colonial growth taking place on and around small lumps of hardened mud, which would explain the irregular shape of the cavity. D. Complete ovoid or spindle-shaped zoaria with the axial cavity, if any, sealed off and concealed by further growth. This category is clearly the more advanced stage of C. Judging from the orientation of the orifices, the blunt part of the ovoid or spindle is the proximal, the tapering end the distal side of the colony. The arrangement of six zooecia radiating from the "emanation-point of zoid rows" (cf. Silen, 1947, text· fig. 44) is always found on the blunt, proximal side. The zooecia and orifices of category A are slightly smaller than those of categories B, C and D, but this is what may be expected in juvenile colonies. As all the zooecia, irre· spective of zoarial category, are characterized by 1) a hippoporine orifice, 2) an open "special chamber" distally to the orifice, 3) the lack of ovicells, 4) a coarsely tuberculated frontal wall, and 5) the occasional presence of a small lateral avicularium, one is forced to conclude as to the identity' of all four categories A, B, C and D. Categories C and D have been described as Fedora nodosa Silen (1947, p. 53, pl. 4, figs. 22, 23) from Alba· tross Station D.2398, 227 fathoms, in the NE Gulf of Mexico (Silen's depth and location "West Indies" being rather inaccurate). Category A comprises the great majority of all occurrences of this species in less than 100 fathoms. Category C and D zoaria on the other hand were not found in less than 196 fathoms. This strongly suggests that, although the larvae may operate and settle in neritic depth, conditions on the continental shelf are really unfavourable to adult growth. The not uncommon occurrence of in crusting zoaria (category A p.p., B) has led me to examine Silen's interpretation of the zoarial growth habit in the living Fedora nodosa more critically. The semi-ovoid or egg-shaped (category C and D) colonies of this species are considered by Silen (l.c., p. 27 and text-fig. 43) to be "internodes connected by chitinous tubes (transformed zoids) to nodose branches that emanate from the encrust­ing original part of the zoarium with the ancestrula". The question whether these nodose branches were standing upright on or hanging downwards from the supporting medium was left undecided (l.c., p. 28). As the nature of these chitinous tubes has a direct bear· ing on the problem, it is necessary to quote Silen in full on this point (l.c., p. 13): "In the material of Fedora nodosa n. sp. (p. 53) there occurs a zoarium from which a strong tube extends at the point from which the zoid rows of the zoarial body emanate (text· fig. 41, pl. 4, fig. 22). This is a tube of a structure quite different from those of the Conescharellinidae. It is stiff, its chitinous walls are comparatively thick and are, so to speak, undulated. It widens considerably towards the end that is directed from the zoarium. All these features point to the mode of life of this zoarium being as follows. It is fixed to some substratum by the tube and stands stiffly out from · that substratum. A short (broken) tube of the same structure emanates in the same way from one of the remaining 12 zoaria of this species; the others are without these appendages. (All the zoaria are dry, cf. p. 14.) From the opposite end of this second zoarium there emanates a short (broken) tube of the same structure but thinner (text-fig. 42). This fact shows that what has been called the zoarium above is not the entire zoarium but only a peduncu­late portion of it. When alive it was continued by a tube that led to another portion of probably the same appearance. Thus the living zoarium certainly had the structure schematically shown in text-fig. 43. It is even possible that several similar portions fol· lowed each other in a row, all of them connected by tubes of the structure described above." Silen further stated (l.c., p. 14) : "These tubes, however, are of a different and more solid structure than those of the Conescharellinidae, and thus the possibilities for their preservation are greater. They are, however, fragile enough, as I found when I happened to break one of them though it was only very slightly touched". In May 1956, during a visit to the U.S. National Museum, I had the opportunity to examine 17 topotype specimens of F. nodosa from Albatross Station D.2398, all of which had at least a few opercula still in situ. To my surprise no chitinous tubes occur~ed in these specimens, although in view of the frequent occurrence of other chitinous parts (i.e. the opercula), one would certainly have expected them to be present, if they really are an essential part of the colony. My suspicion was further raised when I started to find chitinous tubes similar to those described by Silen attached to the zoaria of other species of Bryozoa in the collections of the Division of Invertebrate Paleontology, U.S. National Museum. In several dry zoaria of Mamillopora cupula, from Fowey Light, 15 mi S of Miami, 40 fathoms, for instance, one or more of the depressions on the inside of the cup are still covered by a brownish, very fragile, chitinous membrane. Canu and Bassler ( l 928a, p. 153) refer to these dorsal depressions in M. tubersosa and M. cavernulosa as "hydrostatic cavities". In the centre of this membrane a small, circular opening is preserved, and in the more complete preser­vation a brownish, very fragile, finely annulated and somewhat flaring, chitinous tube emerges from this pore, very similar though not quite as long as the tube connected to Sile~'s specimen of F. nodosa (I.e., pl. 4, fig. 22). I have also observed these tubes on the concave side of specimens of Cupuladria canariensis from the same locality. In a few dry specimens of Mamillopora cupula from Albatross Station D.2639, 56 fathoms, Straits of Florida, similar brownish tubes were found attached to the convex side of the zoarium, directly emerging from the zooecial orifices. The longest tube measured in the latter specimens was approximately 5 mm and had gained considerably in diameter at its flar­ing end. The obvious conclusion from these observations was that the association bryo­zoan-chitinous tube is purely incidental, and that the tubes must form part of a different sessile organism. I have submitted the specimens discussed in the previous paragraph to the distinguished opinions of Dr. Marian Pettibone and Dr. Frederick M. Bayer of the Division of Marine Invertebrates, U.S. National Museum, and both suggested that the tubes probably repre· sent the chitinous perisarc of a hydroid. This opened the possibility that the tubular at­tachments described in F. nodosa would also be of hydroid origin. Later in 1956 Dr. Alfred R. Loeblich Jr., who had followed this development with keen interest, very obligingly sent me a selection of ovoid and semi-ovoid colonies from Albatross Station D.2399, 196 fathoms, located in the close vicinity of Albatross Station D.2398, and therefore from the type area of F. nodosa. Indeed, 24 zoaria appeared to be­long to F. nodosa and among these there is a large and perfectly ovoid zoarium with a chitinous tube of slightly less than 3 mm attached to it. This tube is in all respects similar to the one described by Silen, except that its expanded base is not attached to the proximal "emanation-point" (l.c., text-figs. 41, 44), but is sitting right on top of a zooecium in the proximal part of the colony. This specimen has been examined by Miss P. M. Ralph and Dr. W. J. Rees of the Department of Zoology of the British Museum (Natural History). Miss Ralph immediately recognised the chitinous tube as "the covering case (Hydro­theca) of the polyp of a Scyphomedusa." Dr. Rees not only expressed his desire to obtain the specimen for the scyphozoan collection, but also tentatively identified the genus as "Stephanoscyphus?" This, I think, settles the issue. The chitinous tubes no longer being instrumental in connecting the zoarium of F. nodosa with the substratum, one can only speculate as to an alternative mode of living. The tendency, observed in category B zoaria, of the larva to settle upon and of the colony partially or entirely to envelop small foreign objects strongly suggests an analogy with the zoarial growth of Cupuladria, Discoporella and Lunulites. The adult zoarium of F. nodosa would thus rest on the bottom with its (distal) growing edge and gradually raise itself above the sea floor with the blunt ancestrular region ("emanation-point") directed upward. It is here, I believe, that a discussion of the "special chambers" is in order. "Special chambers" occur very persistently distally to the orifices in both F. edwardsi Jullien (the type species, by monotypy, of Fedora Julien, 1883 and spelled correctly on p. 529 of Jullien's paper) and in F. nodosa Silen, to which the following description applies. They are open in most cases and a small pore at the bottom leads into the interior of the zoarium. In the proximal, ancestular part of the zoarium they are closed by a calcareous deposit, as described by Silen ( l.c., p. 55) . Their formation is best seen by turning the distal side of a semi-ovoid or hemispherical colony upward, so as to expose the growing edge. They are then seen being formed as diamond-shaped concavities at the periphery of the zoarium, astride the distal crest of the zooecia, with the small pore situated in the angle nearest to the zoarial axis. As Silen (l.c ., p. 52 points out, Jullien ( 1883, p. 513) ave an accurate description of these structures in F. edwardsi, but it is now recognised that they are not reproductive organs. According to Silen (l.c., p. 52), "its mode of formation shows that it is of zoidal nature, a dwarfed heterozoid." In order to arrive at some conclusion about their possible function, the following ob­servations must first be mentioned: 1) "special chambers" persistently occur distally to all zooecia in all colonies, even in juvenile zoaria with not more than three zooecia (Pl. VII, fig. 5). Conclusion: "special chambers" do have an absolutely essential function in the colony. 2) The closure of the "special chambers" by a calcareous deposit in the proximal, an­cestrular part by the zoarium suggests that their presence is no longer needed in that part of the colony. Conclusion : their function is primarily required in the distal part of the zoarium. 3) Unlike the small distal chambers which accommodate the vibracular setae in Cupu­ladria and Discoporella, the "special chambers" in F. nodosa are perfectly sym­metrical. Their opening is plain, without projecting structures which might serve for the articulation of the base of a vibracular seta. 4) One of the "special chambers" at the growing edge of a specimen of F. nodosa from Caroline 1933 Station 94 with the opercula still intact was found occupied by an elongate chitinous structure suggestive of a short anchoring filament or rootlet. Tentative conclusion: the "special chambers" are rootlet chambers. 5) In the adult hemispherical or semi-ovoid colonies the axes of the "special chambers" at the growing edge are located approximately in one single plane perpendicular to the zoarial axis. Final working hypothesis: the special chambers give rise to a circle of radiating anchoring filaments or rootlets at the growing edge of the colony perpendicular to the zoarial axis. It is assumed that they contribute to greater stability of the adult colony by attaching themselves to the substratum. The function of the "special chambers" would thus harmoniously fit the conception arrived at pre.viously of the adult zoarium resting on the bottom with its (distal) growing edge and gradually raising itself above the sea floor with the blunt ancestrular region ("emanation-point" ) directed upward. In this connection it may be significant that one of the type figures (pl. 4, fig. 22) of F. nodosa, representing a living zoarium preserved dry according to Silen (I.e., p. 53), shows a lump of bottom sediment consisting of smaller Foraminifera, etc. attached to the distal side of the colony, i.e. where the living zoarium would be in actual contact with the bottom sediment if our conclusions are substantially correct. The figure is thus actually upside down, the hydroid growing vertically upward from the proximal end of the supporting Fedora. The same situation exists in the "Stephanoscyphus?"-bearing specimen from Albatross Station D.2399. None of the topotypes and none of our other specimens have ovicells and this, together with the fact that Silen did not observe them, probably means that ovicells do not deYelop in Fedora nodosa. This is also Silen's conclusion (I.e., p. 57, 58, in the remarks under F edorella minima) . Occurrence North-western Gulf: Vema-3 I954 Drag 6 Univ. of Houston sample I2 Cavalier I956 Station 3I7 Cavalier I956 Station 3I6 Cavalier I956 Station 311 Cavalier I956 Station 309 Cavalier I956 Station 308 Cavalier I956 Station 307 Cavalier I956 Station 306 Cacalier I956 Station 278 Cavalier I956 Station 225 Cavalier I956 Station 226 Cavalier I956 Station 227 Cavalier I956 Station 229 Eastern Gulf: Sandpile Bank Hydrographer I94I/ 42 Station 50 Albatross 1885 Station D.2398 D.2399 Albatross I885 Station Atlantis I95I Station I53 Atlantis I95I Station I54 Atlantis I95I Station I55 Atlantis I95I Station I56 Number of specimens and category to which they belong 2A IA lOA 5A,3 B IA 4A I3 A 3A 7A I8 A, I2 B IA IA 8A 8A 2IA I frgt. I7 C&D 24C&D 7 frgts .. 3A 4A,2B 9A 2A 30 fathoms 3I l/3 fathoms 50 fathoms 50 fathoms 70 fathoms 57 fathoms 40 fathoms 351/z fathoms 35 fathoms 38 fathoms 50 fathoms 56 fathoms 371/z fathoms 57 fathoms 49 fathoms 103.8 fa th ams 227 fathoms I96 fathoms IOO fathoms 80 fathoms 64 fathoms 43 fathoms 32 fathoms Atlantis 1951 Station 157 14A 34 fathoms Atlantis 1951 Station 158 SA 33 fathoms Atlantis 1951 Station 159 2A 28 fathoms Atlantis 1951 Station 160 lA 25 fathoms Atlantis 1951 Station 161 19A 22 fathoms Vema-3 1954 Dredge #1 4A 117 fathoms Vema-3 1954 BT #2 Vema-3 1954 Dredge #2 Florida Straits: off Molasses Reef Light 15 B 122 fathoms lA, 1 B 120 fathoms E of Triumph Reef 3A 45 fathoms Additional occurrence ~of Puerto Rico and the Virgin Islands Caroline 1933 Station 9 7C&D 240 fathoms Caroline 1933 Station 9 10 C & D } 400 fathoms Caroline 1933 Station 94 lB Fossil Occurrence Pleistocene ("Upper Marine") of Mississippi River Delta, South Pass Block 6 Area, State Lease 2590 # 1, in ditch cuttings from the interval 500-1100', 12 A & B. Distribution E Golf of Mexico Albatross 1885 Station D.2398, SSE of Fort Pickens, Florida, 227 fathoms. Family TUBULIPORIDAE JOHNSTON, 1838 Genus Stomatopora Bronn, 1825 Stomatopora trahens (Couch) (Pl. VIII, fig. 6) NonAlecto granulata Milne-Edwards (1838, p. 205, pl.16, figs.13, 13a). Alecto granulata Johnston (1847, p. 280, pl. 49, figs. l , 2) , Busk (1975, p. 24), Busk ( 1886, p. 22) . Tubulipora trahens Couch ( 1841, p. 71) , Couch ( 1844, p. 105, pl. 19, fig. 5, non fig. 3, fide Gregory, 1896, p. 48, footnote). Stomatopora granulata (Milne-Edwards) Hincks (1880a, p. 425, pl. 57, figs. 1, 2) , Nor­man (1909, p. 278) , O'Donoghue and O'Donoghue (1926, p. 17) , Borg (1926, p. 359, text-figs. 67, 68 ), Marcus (1940, p. 52, text-fig. 26 ), Osburn (1953, p. 619, pl. 65, figs. 1, 2) . Stomatopora granulata Hincks: O'Donoghue and O'Donoghue (1923, p. 11) . Material Locality 55 ( 1). Remarks Alecto granulata Milne-Edwards is the name of a Cretaceous fossil from the "gres vert inferieur" of Vassy, Haute-Mame, France. The identification of the Recent form com­ New Additions to the Bryozoan Fauna of the Gulf of Mexico monly labelled Stomatopora granulata (Milne-Edwards) with the Cretaceous fossil formally entitled to that name is open to serious doubt. It does seem rather improbable that a species, in the Linnean sense, would attain a life-span of some 100 million years. Besides, there are a number of morphological differences, as Gregory ( 1896, p. 4 7; 1899, p. 7) has shown. Nevertheless, the practice of using Milne-Edwards's name for the Recent form has persisted into modern literature. I have here followed a suggestion by Gregory ( 1896, p. 48; 1899, p. 7), who proposed to distinguish the Recent species as Stomatopora trahens (Couch). It is interesting to observe how the pattern of growth in the dichotomising Stomatopora, striving to coYer the largest possible area of the available substratum, anticipates an im­minent contact between the zooecia of neighouring branches. For, as Canu and Bassler (1920, p. 654) have observed, "the branches of the same zoarium of Stomatopora . .. never grow oYer each other . . . ; a branch is arrested in growth when it encounters another." A first step (A) towards the avoidance of such a lateral contact is the progressive re­duction of the angle of branching in the second and later dichotomies (Lang, 1904, p. 319). A further measure (B) to this end is the skipping of dichotomies. In Stomatopora trahens each zooecium usually leads into a distal dichotomy. But there are some zooecia which produce only one distal zooecium, the branch thus continuing in a straight line in order to find more "elbow-room" for the next bifurcation. Frc. 4. Diagram of growth pattern observed in specimen of Stomatopora trahens (Couch) . "Spoked wheels" represent calices of small branching coral which serves as substratum. New Additions w the Bryozoan Fauna of the Gulf of Mexico The angles of divergence at the various dichotomies in our single Gulf specimen are shown in text-fig_ 4. Our observations on this large specimen suggest that-unless irregu­larities of the substratum dictate otherwise--the incidence of ( B) is to some extent de­pendent on the progression of (A). Or, to put it more specifically: on a plain surface no dichotomies are skipped distally to a bifurcation with an angle of 90° and more. In our specimen values smaller than 90° are reached only at the third and later dicho­tomies. Therefore, skipping of dichotomies also occurs only after the third and later dichotomies. It is also observed that the very small angles (30-43°), which are found at some bifurcations of the sixth and higher order, invariably give rise to skipped dichotomies. Occurrence North-western Gulf: Cavalier 1956 Station 39 81;3 fathoms Distribution E Atlantic from Spitzbergen to the Cape Verde Islands Mediterranean off Inaccessible Island, Tristan da Cunha Straits of Magellan off Santa Catalina Island, and off San Pedro, Southern California British Columbia Tizard Reef, China Sea 60-90 45 12-30 fathoms fathoms fathoms Family CRISIIDAE JOHNSTON, 1838 Genus Crisulipora Robertson, 1910 Crisulipora occidentalis Robertson (Pl. VII, fig. 6) Crisulipora occidentalis Robertson (1910, p. 254, pl. 21, figs. 22, 23, 24) , Okada (1917, p. 342), Marcus (1937, p. 21, pl. 3, fig. 5), Osburn (1953, p. 686, pl. 72, fig. 6) , Lagaaij (1959, p. 484, text-fig. 5). Crisia sp. Canu and Bassler (1928a, p. 157, pl. 30, figs. 1, 2). Material Locality 2(1), 55(4), 69(3), 70(1), 71(2), 72(1), 74(23), 77(3,) 88(29), 89(2), 94(11), 99(2), 100(1), 101(3), 102(9), 103(32), 104(3), 111(25) , 145(3), 150(105)' 179(14)' 180 (1)' 181 (2)' 353 (3)' 379 (23)' 380 (34), 381 (18)' 382(49), 383(50), 384(12) , 385(13), 386(62), 387(97), 388(22), 389(37) , 390(67), 391(5), S92(4), 394(12), 395(17), 396(4), 414(2), 416(14), 418(1), 419(1), 443(9) , 444 (numerous), 457 (3). Remarks This form has previously been recorded from the Gulf of Mexico under a different name. After examining the specimen (U.S.N.M. Cat. No. 648060) , I am convinced that the "curious fragment with white joints," described and figured by Canu and Bassler (1928a) from Albatross Station D.2405, 30 fathoms, belongs here, rather than to Crisia ramosa Harmer as suggested by Osburn ( 1940, p. 329). As in other jointed species, the dead colonies of Crisulipora occidentalis soon fall apart into their individual internodes. These isolated internodes, or parts thereof, ac­cumulate freely on the bottom. This may partly explain the long list of occurrences here cited. Live specimens, with their internodes still connected by chitinous joints, were brought up at two of the forty-eight Gulf stations here listed: SSW of John's Pass, Florida, 34 fathoms, and Cavalier 1956 Station 322, 23 fathoms (Claypile Bank, speci­ mens taken off large Spondylus). Occurrence North-western Gulf: off Rio Grande Cavalier 1956 Station 39 Vema-3 1954 Core #65 Univ. of Houston sample 15 Univ. of Houston sample 11 Univ. of Houston sample 12 Univ. of Houston sample 5 Heald Bank Cavalier 1956 Station 322 Cavalier 1956 Station 321 Cavalier 1956 Station 316 Cavalier 1956 Station 311 Cavalier 1956 Station 310 Cavalier 1956 Station 309 Cavalier 1956 Station 308 Cavalier 1956 Station 307 Cavalier 1956 Station 306 Cavalier 1956 Station 299 Cavalier 1956 Station 273 Cavalier 1956 Station 278 Cavalier 1956 Station 227 Cavalier 1956 Station 228 Cavalier 1956 Station 229 Eastern Gulf: off Choctawhatchee Bay off Cedar Keys off Egmont Key Vema-3 1954 Dredge #2 SSW of John's Pass, Florida Florida Straits: S of Sombrero Key Additional occurrence 50 fathoms 81/s fathoms 30 fathoms 291/6fathoms 29% fathoms 31% fathoms 31 fathoms 101lz fathoms 23 fathoms 271lz fathoms 50 fathoms 70 fathoms 60 fathoms 57 fathoms 40 fathoms 351lz fathoms 35 fathoms 111/6 fathoms 24 fathoms 38 fathoms 371lz fathoms 271lz fathoms 57 fathoms 151/s fathoms 8-64 fathoms 8-11% fathoms 29 fathoms 34 fathoms 25 fathoms Specimen, labelled "Crisulipora" (U.S.N.M. Cat. No. 9739), from Albatross Station D.2411, Gulf of Mexico, 27 fathoms Distribution Gulf of Mexico 30 fathoms New Additions to the Bryozoan Fauna of the Gulf of Mexico Bay of Santos, Brazil American Pacific coast from Point Conception, California to the Lobos de Afuera Islands, Peru Bay of Sagami, Japan 20 0-47 metres fathoms Fossil distribution Upper Middle Miocene of Bowden, Jamaica, B.W.I. Family TUBULIPORIDAE JOHNSTON, 1838 Genus ldmidronea Canu 1919 !dmidronea fiexuosa (De Pourtales) (Pl. VII, fig. 7) ldmonea fiexuosa De Pourtales (1867, p. 111) . Tubulipora fiexuosa Osburn (1953, p. 653, pl. 71, fig. 11, cum syn.). Material Locality 412 ( 1), 458 (10), 458a ( 3), 469 (1). Remarks The specimens taken off Molasses Reef Light have all gone through the process of alteration which has affected so many calcareous organisms in the deeper samples from the Florida Straits. They now appear as highly polished, brownish internal casts of the original system of hollow zooecial tubes. X-ray analysis of selected specimens of Bryozoa in this condition, made at the E &P Research Laboratory of Shell Development Company, Houston, Texas, indicate an aragonite content of only 23-30%, versus 70-77% calcite. Yet two characters remain which permit identification: 1) the slender, often somewhat curved, zoarial branches; 2) the occurrence in each fascicule of not more than two zooecia. The single Oregon specimen, on the other hand, is extremely well preserved, with the strongly produced peristomes in each fascicule adnate over their entire length (Pl. VII, fig. 7). Occurrence Eastern Gulf: Vema-3 1954 Station BT #2 96 fathoms Florida Straits: off Molasses Reef Light 120-122 fathoms NW of Cay Sal Bank 1.30 fathoms American distribution off Havana, Cuba 270 fathoms Cape le Vela, Colombia j Gulf of Venezuela 22-41 fathoms Aruba Tortuga Island Raza Island, Gulf of California 40 fathoms James Island, Galapagos 54 fathoms Acknowledgments This report draws heavily upon the collection of washed residues of marine bottom sediments in the possession of the Exploration and Production Research Division of Shell Development Company, Houston, Texas, U.S.A. Samples were examined from both the Eastern and the Western Gulf of Mexico, including some collected by the Hydrographer in 1941-1942, the Atlantis in 1951, the Vema in 1954, the Oregon in 1955 and the Cavalier in 1956. The first four ships have a well-known record as oceanographic and fishery survey vessels. The Cavalier is a modified shrimp boat which was chartered by Shell Development Company for a special survey in the Wes tern Gulf. Permission by the Shell Development Company and Shell International Research Maatschappij N.V. jointly, to publish this paper is here gratefully acknowledged. The provision of other samples by friends and colleagues is here gratefully ac­knowledged: Dr. H. A. Bernard, Messrs. R. Wright Barker, H. Ode, B. S. Parrott, and S. J. Rosenfeld of the Houston laboratory, Dr. R. N. Ginsburg of Coral Gables, Fla., and Dr. G. L. Voss of the Marine Laboratory of the University of Miami, Fla. Thanks are also due to Dr. G. A. Cooper, Head Curator of the Department of Geology, United States National Museum, Washington, D. C. for the facilities extended to me for studying the types of Recent Gulf Bryozoa in the collection and, at a later stage, for the loan of specimens. Dr. A. R. Loeblich, Jr. and Dr. R. S. Boardman have kindly arranged these loans, and Dr. Boardman has also most obligingly compared some specimens with the types. Similar facilities for which I am very grateful were provided by the Keeper of the Department of Zoology of the British Museum (Natural History). In London I have also received the generous help and encouragement of Dr. Anna B. Hastings and Dr. H. Dighton Thomas. Dr. Hastings has also critically read the manuscript. Her comments and advice have placed me under great obligation. I am also indebted to Prof. Dr. H. Boschma, Prof. Dr. A. H. Cheetham, Dr. J. W. Hedgpeth and Dr. Meredith L. Jones for several helpful suggestions. The figures on Plates I-VII were drawn by Mr. L.B. Isham, and Mr. R. R. J. Davilar devised text-figure 3. The photographs on Plate VIII were taken by Mr. J. H. H. Van Gigch. Manuscript received at the Institute of Marine Science March 15, 1962. Literature Cited Audouin, V. 1826. 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Hist. 6(4): 1-24, pis. 1-3. Waters, A. W. 1897. Notes on Bryozoa from Rapallo and other ~editerranean Localities, chiefly Cellulariidae. J. Linn. Soc. (Zoo!.) 26: 1-21, pis. 1-2. Waters, A. W. 1899. Bryozoa from Madeira. J. Roy. Mier. Soc.: &-16, pl. 3. Waters, A. W. 1906. Bryozoa from Chatham Island and d'Urville Island, New Zealand ... Ann. Mag. nat. Hist. 7(17): 12-23, pl. 1. Waters, A. W. 1913. The Marine Fauna of British East Africa and Zanzibar from Collections made by Cyril Crossland, M.A., B.Sc., F.Z.S., in the years 1901-1902. Bryozoa-Cheilostomata. Proc. zool. Soc. London. (1913): 458-537, pis. 64-73. Waters, A. W. 1918. Some Collections of the Littoral Marine Fauna of the Cape Verde Islands, made by Cyril Crossland, M.A., B.Sc., F.Z.S., in the Summer of 1904. Bryozoa. J. Linn. Soc. (Zoo!.) 34: 1-45, pis. 1-4. Waters, A. W. 1925. Ancestrulae of Cheilostomatous Bryozoa. II. Ann. ~fag. nat. Hist. 9(15): 341­352, pis. 21-22. 1 Date unknown, but of no consequence, as all the corresponding specific names were issued by Audouin in 1826. APPENDIX List of localities Locality number Lat. N Long. W Depth in fms Various collecting details 2 25°47' 96°27' 50 4 5 10 Corpus Christi Bay Corpus Christi Bay Corpus Christi Bay % % 1% Coll. by Messrs. E. A. Lohse & W. A. Price, June 1956 Coll. by Messrs. E. A. Lohse & W. A. Price, June 1956 Coll. by Messrs. E. A. Lohse & W. A. Price, June 1956 13 St. Joseph Island, Aransas Pass near beach Coll. by Mr. H. Ode, March 1957 14 Mud Is., Aransas Bay %-1 Coll. by Mr. Donald Moore, 29th June 1954 16 28°50' 5" 95°23'53" 4 Cavalier 1956 Station 15 23 28°43'18" 95°19' 9" 8% Cavalier 1956 Station 12 26 28°52' 5" 95°19'42" 3% Cavalier 1956 Station 5 28 31 due E of Freeport 28°53'16" 95°15'30" beach 6% Coll. by Dr. H. A. Bernard, 20th ·March 1956 Cavalier 1956 Station 2 New Additions to the Bryozoan Fauna of the Gulf of Mexico List of localities (continued) localih· number Lat. N Long. W Depth in fms Various collecting details 36 28°47'30" 95°15'24" 9% Cavalier 1956 Station 20 55 60 28°50'36" 95° 8' 5" Galveston Island, oppo­ 81/a Cavalier 1956 Station 39 site Mud Island (San Luis Pass) beach Coll. by the author 61 Galveston Island, near San Luis Pass beach Coll. by the author 62 Galveston Island, 3 mi. SW of Stewart Rd. beach Coll. by Mr. H. Ode, 24th March 1957 63 Galveston Island beach Coll. by Mr. B. S. Parrott, November 1956 64 Galveston Island, near 8 Mile Road beach Coll. by Dr. H. A. Bernard, 12th December 1955 65 Galveston Island, at Galveston beach Coll. by Mr. H. Ode, 31st December 1956 67 28°40' 94°33' 15 Coll. by University of Houston students, samples no. 1-4 (see Kellough, 1956) 68 28°10'42" 94°15' 30 Vema-3 1954 Drag 6 and Core #65 (top 0-12") (see 69 70 Vicinity of Stetson Bank 28° 9'53" 94°17'52" Ewing and Ericson, 1954) approx. 30 Anchor sample, don. by Mr. S. J. Rosenfeld 29% Coll. by University of Houston students, sample no. 15 71 28° 9'34" 94°17'26" 29% (see Kellough, 1956) Coll. by University of Houston students, sample no. 11 72 28° 9'18" 94°1 i' 4" 311/a (see Kellough, 1956) Coll. by University of Houston students, sample no. 12 74 28°11'22" 94°15'30" 31 (see Kellough, 1956) Coll. by University of Houston students, sample no. 5 76 77 Heald Bank 29° 4' 94°14' 81/a 10Yi (see Kellough, 1956) Dredge sample 78 29° 3'15" 94°18'45" 6% Cavalier 1956 Station 331 80 28°58'45" 94°18'45" 6 . Cavalier 1956 Station 329 86 28°33' 94°12'15" 20 Cavalier 1956 Station 324 88 28°20' 94° 9' 23 Cavalier 1956 Station 322 89 28°17'30" 94° 8'30" 27Yi Cavalier 1956 Station 321 93 27°58'45" 93°49'45" 50 Cavalier 1956 Station 317 94 27°54'15" 93°47'45" 50 Cavalier 1956 Station 316 95 27°48'45" 93°45'30" 92 Cavalier 1956 Station 315 97 27°41' 93°42'15" 200 Cavalier 1956 Station 313 99 27°51'30" 93°47' 70 Cavalier 1956 Station 311 100 27°53'45" 93°46'30" 60 Cavalier 1956 Station 310 101 27° 56'15" 93 ° 46' 57 Cavalier 1956 Station 309 102 28° 4' 93°44'20" 40 Cavalier 1956 Station 308 103 28° 9'30" 93°43'15" 35Yi Cavalier 1956 Station 307 104 28°16'15" 93°42'15" 35 Cavalier 1956 Station 306 108 28°43' 93°34'45" 15 Cavalier 1956 Station 302 109 110 28°49' 28°52'30" 93°33'15" 93°32' 121/a 11 Cavalier 1956 Station 301 Cavalier 1956 Station 300 111 28°59'15" 93°30'15" ll1k Cavalier 1956 Station 299 113 29°11'30" 93°26' 9 Cavalier 1956 Station 297 115 29°19'20" 93°36'30" 7 119 29°24'42" 93°20' 7 Cavalier 1956 Station 292 120 29° 26'24" 93°19'55" 4 Cavalier 1956 Station 291 126 29°27' 92° 4'30" 2 132 29°11'48" 91°36' 3% Cavalier 1956 Station 259 145 28°31'30" 91°49'15" 24 Cavalier 1956 Station 273 150 28° 5'15" 91 °58' 38 Cavalier 1956 Station 278 17/ li8 28°10'30" 28° 8'30" 91° 1' 91° l' 50 56 Cavalier 1956 Station 225 Cavalier 1956 Station 226 179 28° 6'30" 91 ° l' 37Yi Cavalier 1956 Station 227 180 181 2a 0 5' 28° 4' 91° 1· 91° 1' 271/z 57 Cavalier 1956 Station 228 Cavalier 1956 Sta ti on 229 193 28° 7'30" 90°13'30" 100 Cavalier 1956 Station 176 226 Grand Isle, Louisiana beach Coll. by Mr. B. S. Parrott 332 29° 4'24" 88°43' 49 Nautilus Station 349 28° 32' 88° 6' 1181 Albatross 1885 Station 2383 (see Townsend, 1901) 351 29°46'30" 86°58' 103.8 Hydrographer 1941/42 Station 50 (see Lowman, 1949) Locality number 353 354 356 357 358 359 360 361 363 365 367 368 369 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 399 401 403 411 412 413 414 415 416 417 418 419 420 422 424 426 427 428 429 430 431 432 434 442 443 444 457 458 458a 461 464 465 469 Lat. N 30°15' 30°13' 30° 5'58" 30° 5'20" 30° 4'40" 30° 4' 30° 3'20" 30° 2'42" 30° 1'24" 30° 6" 29°33' 28°45' 28°44' 28° 9' 28°11'30" 28°14' 28°16'30" 28°19' 28°22' 28°24'30" 28°27' 28°30' 28°32' 28°35' 28°38' 28°41' 28°43'30" 28°46' 28°49' 28°51'30" 28°54' 28°55' 28°56'30" 28°58'48" 29° 1'24" 29° 3'55" 25°50' 26°10' 27°36'27" 27°36'27" 27°36'27" 27°36'27" 27°36'27" 27°36'27" 27°36'27" 27°36'27" 27°36'27" 27°36'45" 27°36'16" 27°36'44" 27°37' 8" 27°38' 9'' 27°39'54" 27°41'14" 27°42' 8" 27°44'51" 27° 8' 26°50' 26°25' 24°35'30" 24°54' 24°54' 25°13'15" 25°28'30" 25°28'30" 24° 3' Long. W 86°11' 86° 8' 85°45'39" 85°46'32" 85°47'25" 85°48'16" 85°49'10" 85°50' 3" 85 °51'54" 85°53'40" 86° 8' 86°26' 86°18' 85° 7' 85° 2' 84°57' 84°52' 84°46'30" 84°41' 84°36' 84°31' 84°25'30" 84°20' 84°14' 84° 8' 84° 2' 83°56' 83°50' 83°44' 83°39'30" 83°34'30" 83°28'30" 83°22' 83°16'42" 83°13'20" 83° 9'50" 84°30' 84°20' 83°11' 83° 8'57" 83° 6'52" 83° 4'48" 83° 2'42" 83° 30" 82°58'18" 82°56' 6" 82°51'42" 82°47'18" 82°43'18" 82°41'18" •. 82°39'20" 82°37'27" 82°36' 6" 82°34'43" 82°33'36" 82°31'54" 83 °30' 83°40' 83°32' 81° 6'55" 80°15'30" 80°15'30" 80° 7' 80° 5'45" 80° 5' 80°30' List of localities (continued) Depth in £ms Various collecting details 151h Hydrographer 1941/42 Station 40 (see Lowman, 1949) 12% Hydrographer 1941/42 Station 39 (see Lowman, 1949) Coll. by Mr. Donald Moore, August, 1954 Coll. by Mr. Donald Moore, August, 1954 Coll. by Mr. Donald Moore, August, 1954 Coll. by Mr. Donald Moore, August, 1954 Coll. by Mr. Donald Moore, August, 1954 Coll. by Mr. Donald Moore, August, 1954 Coll. by Mr. Donald Moore, August, 1954 Coll. by Mr. Donald Moore, August, 1954 21 Ya 227 196 100 80 64 43 32 34 33 28 25 22 20 20 17 17 16 14 12 11% 11 8 5'12 41h 3% 117 96 12% 11 % 10lf2 10% 8% 81/a 8 7% 5lf2 6% 7 6% 6 4% 5% 4% 21h 4 23 29 34 25 122 120 78 45 58 150 Hydrographer 1941/42 Station 45 (see Lowman, 1949\ Albatross 1885 Station 2398 (see Townsend, 1901) Albatross 1885 Station 2399 (see Townsend, 1901) Atlantis 1951 Station 152 Atlantis 1951 Station 153 Atlantis 1951 Station 154 Atlantis 1951 Station 155 Atlantis 1951 Station 156 Atlantis 1951 Station 157 Atlantis 1951 Station 158 Atlantis 1951 Station 159 Atlantis 1951 Station 160 Atlantis 1951 Station 161 Atlantis 1951 Station 162 Atlantis 1951 Station 163 Atlantis 1951 Station 164 Atlantis 1951 Station 165 Atlantis 1951 Station 166 Atlantis 1951 Station 167 Atlantis 1951 Station 168 Atlantis 1951 Station 169 Atlantis 1951 Station 170 Atlantis 1951 Station 171 Coll. by Mr. Donald Moore, August 1954 Coll. by Mr. Donald Moore, August 1954 Coll. by 'Mr. Donald Moore, August 1954 Vema-3 1954 Dredge #1 Vema-3 1954 BT #2 Coll. by Mr. Donald Moore, August 1954 Coll. by Mr. Donald Moore, August 1954 Coll. by Mr. Donald Moore, August 1954 Coll. by Mr. Donald Moore, August 1954 Coll. by Mr. Donald Moore, August 1954 Coll. by Mr. Donald Moore, August 1954 Coll. by 'Mr. Donald Moore, August 1954 Coll. by Mr. Donald Moore, August 1954 Coll. by Mr. Donald Moore, August 1954 Coll. by Mr. Donald Moo~e, August 1954 Coll. by Mr. Donald Moore, August 1954 Coll. by Mr. Donald Moore, August 1954 Coll. by Mr. Donald Moore, August 1954 Coll. by 'Mr. Donald Moore, August 1954 Coll. by Mr. Donald Moore, August 1954 Coll. by Mr. Donald Moore, August 1954 Coll. by Mr. Donald Moore, August 1954 Coll. by Mr. Donald Moore, August 1954 Vema-3 1954 BT #2 (Top of core) Vema-3 1954 Dredge #2 Coll. by Mr. Dan Steger Coll. by Dr. R. N. Ginsburg (see Ginsburg, 1956) Coll. by Dr. G. L. Voss, 9th July 1950 Coll. by Dr. G. L. Voss, 9th July 1950 Coll. by Dr. G. L. Voss, 9th July 1950 Coll. by Dr. R. N. Ginsburg (see Ginsburg, 1956) Coll. by Dr. R. N. Ginsburg (see Ginsburg, 1956) Oregon 1955 Station NW of Cay Sal Bank, 18th July 1955 New Additions to the Bryozoan Fauna of the Gulf of Mexico List of Genera and Species acadiana, Phoceana Acanthodesia Aetea Alecto americana, Hippodiplosia americana, Lepralia ampla, Figularia anguina, Aeta anguina, Sertularia Antropora Arthropoma asper, Gemelliporella aspera, Gemelliporella Beania bellula, Bellulopora bellula, Colletosia bellua, Electra bellula, Membranipora bernardi, Hippopodina bicornis, Electra bellula rnr. Biflustra boryi, Caberea Boryi, Crisia brongniartii, Chorizopora brongniartii, Flustra Bugula Caberea californica, Chaperia canariensis, Cupuladria Canua caribbea, Vibracellina cavalieri, Euginoma cavernulosa, Mamillopora cecilii, Arthropoma cecilii, Flustra cervicornis, Chaperia Chaperia Chapperia Chorizopora Cleidochasma Codonellina Colletosia columnaris, Phoceana commensale, Conopeum Conopeum constricta, Setosellina contracta, Cleidochasma "ontracta, Hippoporina contracta, Lepralia contracta, Perigastrella contraria, Figularia cornuta, Arthropoma Crepidacantha Cribellopora cribriformis, Codonellina Cribrilaria Crisia Crisulipora crustulenta, Electra ci-ustulenta var. arctica, Electra Cryptosula cupula, Mamillopora Cupuladria Da.cryonella diaphana, Halysisis diaphana, Scruparia Discoporella divae, Monoporella edwardsi, Fedora Electra elegans, Catenicella elegans, Vittaticella Eschara Escharina Euginoma Exochella Fedora Fedorella Figularia flabellata, Membranipora flexuosa, ldmonea flexuosa, Tubulipora Floridina Flustra fusca, Membranipora galeata, Chaperia Gemellipora Gemelliporella Gemelliporina glabra, Gemelliporella goesi, Heliodoma goesi, Setosellina gorgonensis, Hippoporella granulata, Alecto granulata, Stomatopora Hagenowinella Halysisis harmeri, Scrupocellaria hastingsae, Electra Heliodoma hilli, Figularia Hincksina Hippodiplosia Hippoporella Hippoporina Hippothoa hirtissima, Beania horsti, Lacerna horsti, 'Schizopodrella horsti, Schizoporella horstii, Lacerna ldmonea isabelleana, Hippothoa Lacema 'Lagenipora' latirostris, Parellisina laxibasis, Vibracellina Lekythopora Lepralia longicollis, Lekythopora longirostris, Exochella longirostris, Mucronella Lunulites magellanica, Figularia Mamillopora marginata, 'Lagenipora' Membranipora Membrendoecium minima, Fedorella Monoporella monostachys, Electra monostachys, Membranipora montferrandii, Codonellina montferrandii, Flustra Mucronella multicornis, Electra bellula var. Nellia neritina, Bugula nodosa, Fedora occidentalis, Crisulipora oculata, Nellia pallasiana, Cryptosula Parasmittina Parellisina parvicella, Floridina patagonica, Figularia patula, Chaperia patula, Chapperia patula, Membranipora pectoralis, Hippopodina Perigastrella periporosa, Hincksina periporosa, Retevirgula Phoceana Pliophloea poisonii, Crepidacantha prolifica, Smittoidea punctata, Gemellipora Pyrulella radiata, Colletosia radiata, Eschara ramosa, Crisia Retevirgula reticulata, Smittia reticulata, Smittina reticulata, Smittoidea roulei, Setosellina savartii, Acanthodesia savartii, Biflustra Schizopodrella Schizolavella :Schizoporella Scruparia scrupea, Scrupocellaria Scru pocellaria serrata, Lepralia contracta var. Setosella Setosellina signata, Parasmittina signata, Smittia signata, Smittina simplex, Cribellopora Smittia Smittina Smittoidea solea, Crepidacantha Stomatopora strictorostris, Antropora strictorostris, Membrendoecium tenella, Electra tenuis, Acanthodesia tenuissima, Membranipora teres, Crepidacantha poissonii var. teres, Lepralia kirchenpaueri var. trahens, Stomatopora trahens, Tubulipora trichotoma, Cribellopora trichotoma, 'Schizopodrella trichotoma, Schizoporella tricuspis, Exochella tricuspis, Mucronella tuberculata, Membranipora tuberosa, Mamillopora tubigerum, Conopeum tubulata, Retevirgula Tubulipora turrita, Bugula typica, Canua typica, Dacryonella uberrima, Vittaticella Umbonula uvulifera, Lepralia vermiformis, Euginoma Vibracellina Vittaticella vulgaris, Eschara vulgaris, Escharina vulgaris, Schizolavella vulgaris, Schizoporella vulnerata, Membranipora vulnereta, Setosella PLATE I Fig. 1. Electra monostachys (Busk). Station 61. USNM 64811. 40X 2. Membranipora tenuissima Canu. Station 226. USNM 648009. 40X 3. Antropora typica (Canu and Brassier). Station 379. USNM. 648012. 40X 4. Retevirgula tubulata (Hastings). Station 383. USNM 648014. 40X Basal surface with numerous peg-like processes. 5. Retevirgula tubulata (Hastings). Station 383. USNM 648015. 40X Fragment with ovicell. 6. Retevirgula tubulata (Hastings). Station 383. USNM. 648014. 40X Frontal surface of the same specimen as that shown in fig. 4. 6 New Additions to the Bryozoan Fauna of the Gulf of Mexico PLATE II Fig. 1. Setosellina goesi (Silen). Station 367. USNM 648013. 40X 2. Chaperia patula (Hincks). Station 412. USNM 648017. 20X 3. Monoporella divae Marcus. Station 179. USNM 648019. 40X Fragment with ovicell. 4. Monoporella divae Marcus. Station 179. USNM 648020. 40X 5. Floridina parvicella Canu and Bassler. Station i6. USNM 648018. 40X 6. Euginoma cavalieri sp. nov. Station 97. USNM 648022. 40X Holotype. 7. Setosella vulnerata (Busk). Station 458. USNM 648021. 40X 2 1 4 3 5 6 7 New Additions to the Bryozoan Fauna of the Gulf of Mexico PLATE III Fig. 1. Scrupocellaria harmeri Osburn. Station 444. USNM 648025. 40X Frontal view. 2. Scrupocellaria harmeri Osburn. Staticm 444. USNM 648025. 40 X Dorsal view. 3. Caber ea boryi (Audouin) . Station 444. USNM 648026. 40 X Frontal view. 4. Caberea boryi (Audouin) . Station 444. USNM 648026. 40X Dorsal view. 2 PLATE IV Fig. 1. Figularia contraria sp. nov. Station 69. USNM 648027. 40X Holotype. 2. Bellulopora bellula (Osburn). Station 179. USNM 648028. 40X 3. Hippopodina bemardi sp. nov. Station 99. USNM 648030. 40X Holotype. 4. Hippopodina bemardi sp. nov. Station 99. USNM 648031. 40X Paratype. 5. Chorizopora brongniartii (Audouin). Station 395. USNM 648029. 40X 6. Arthropoma cecilii (Audouin). Station 99. USNM 648033. 40X 7. Cribellopora trichotoma (Waters). Station 94. USNM 648034. 40X 8. Cribellopora trichotoma (Waters) . Station 94. USNM 648035. 40X 2 5 6 7 8 PLATE V Fig. 1. Escharina vulgaris (Moll) . Station 69. USNM 648036. 40X 2. Cleidochasma contracta (Waters). Station 99. USNM 648037. 40X 3. Hippoporella gorgonensis Hastings. Station 392. USNM .6'W038. 40X 4. Hippodiplosia americana (Verrill). Station 14. USNM 648039. 40X 5. Exochella longirostris Jullien. Station 99. USNM 648040. 40X 1 2 4 3 5 New Additions to the Bryozoan Fauna of the Gulf of Mexico PLATE VI Fig. 1. Smittoidea reticulata (Macgillivray). Station 99. USNM 648041. 40X 2. Parasmittina signata (Waters). Station 384. USNM 648043. 40X 3. Codonellina mont/errandii (Audouin). Station 94. USNM 648042. 40X 4. Lekythopora longicollis sp. nov. Station 99. USNM 648048. 40X Holotype. 5. Lekythopora longicollis sp. nov. Station 99. USNM 648049. 40X Paratype. 6. Crepidacantha poissonii (Audouin). var. teres Hincks. Station 119. (specimen lost) 40X 7. Phoceana acadiana sp. nov. Station 412. USNM 648045. 20X Paratype. 2 1 5 New Additwns to the Bryozoan Fauna of the Gulf of Mexico PLATE VII Fig. 1. Vittaticella uberrima Harmer. Station 111. USNM 648052. 40X Ordinary biglobulus. 2. Vittaticella uberrima Hanner. Station 111. USNM 648053. 40X Fertile biglobulus. 3. Hal,ysisis diaphana (Busk). Station 390. USNM 648054. 40X Fragment with broken ovicell. 4. Fedora nodosa Silen. Station 104. USNM 648055. 40X Frontal view of juvenile specimen. 5. Fedora nodosa Silen. Station 104. USNM 648055. 40X Distal view of the same specimen as that shown in fig. 4. The "special chambers" are well exposed. 6. Crisulipora occidentalis Robertson. Station 443. USNM 648057. 20X 7. ldmidronea flexuosa (De Pourtales). Station 469. USNM 648058. 40X 3 4 5 7 6 New Additions to the Bryozoan Fauna of the Gulf o/ Mexico 5 6 PLATE VIII Fig. 1. Aetea anguina (Linnaeus). Station 64. USNM 648008. 24X 2. Conopeum commensale Kirkpatrick and Metzelaar. Galveston Island beach, Texas. USNM 648010. 24X The "brown lines" are clearly apparent. Two '"rectangular blocs" are discernible in the fifth vertical row of woecia from the right. 3. Parellisina latirostris Osburn. Station 69. USNM 648016. 24 X Notice the characteristic avicularium and corresponding distal kenozooecium in centre of photograph. 4. Beania hirtissima (Heller). Station 444. USNM 648024. 24 X 5. Figularia contraria sp. nov. Station 69. USNM 648027. 24X Holotype. 6. Stomatopora trahens (Couch). Station 55. USNM 648056. 24X A Study of the Diatom Flora of Fresh Sediments of the South Texas Bays and Adjacent Waters1 E. J. FERGUSON WOOD2 Department of Oceanography and Meteorology Agicu(tural and Mechanical College oj Texas College Station, Texas Abstract This paper gives a list, with illustrations and short descriptions, of the principal diatom;; found in surface sediments of the Texas Bays from Port Isabel to Galveston. From annotations on ocnirrences in collections made in the summer of 1961 it will be seen that the synoptic diatom flora changes in some respects in the different bays and also differs from that of more ea!>terly Gulf port;;. Some 252 diatom species are listed, of which some appear to be new. Introduction The South Texas Bays form an almost continuous waterway from Port IsabeL close to the Mexican Border, to East Bay at Galveston. The bays are connected by the Intra­coastal Waterway, through which passes a great deal of small shipping. It might be ex­pected that epontic species such as the Amphoras and Cocconeis might, in time, become distributed through the bays on the bottoms of ships and barges. In general, the environ­ment consists of shallow bays, separated from the Gulf of Mexico by barrier islands, Padre Island, Mustang Island, St. Joseph's Island, Matagorda Island and Peninsula, and Galveston and Bolivar Peninsulas. There are four passes, Port Isabel, Aransas Pass, Cavallo Pass and Galveston Bay. Tidal rise is only a few inches and does not affect most of the area; run-off is slight except for flash floods. Three collections made from Aransas and Redfish Bays over 3 months showed great consistency in the species observed at each station during that period, so the study may conveniently be regarded as synoptic. Many of the bays are separated from each other by shallow flats or mud banks, or joined by narrow and shallow bayous and might be ex­pected to show certain peculiarities in their flora. This paper deals with the diatom flora collected from the surface 5 mm of the sedi­ments by a corer or an Eckman grab, and contains a table showing the stations at which the species occurred. It does not pretend to be an exhaustive taxonomic study of the diatom flora. Sampling was restricted to May through July, and it is probable that the rarer species were not observed. In order to enlarge the biological record of the Texas Bays and to proYide a ready means for identification by students working in the region, photographs and brief descriptions are given. Editor's note: Because of the importance of the small benthic diatoms in teaching and research along the Gulf Coast, and because of the usefulness of plates in leading students into the genera of the check list, we are including figures which have limitations in resolution. 1 This paper forms part of A &M Project 273, National Science Foundation. 2 Present address, Institute of Marine Science, Miami 49, Florida. 238 A Study of the Diatom Flora of Fresh Sediments of the South Texas Bays The diatoms were identified and photographed from prepared slides in which the sedi­ments were treated with hot HCl for approximately 20 minutes, washed, dried, and mounted in Hyrax. One or two planktonic species, e.g., Bacteriastrum varians and Skeletonema costatum were found. S. costatum was indeed very common in the sediments of Galveston and Matagorda Bays, where it was assuming bloom proportions when the writer left South Texas. Wood ( 1959a) records the germination of spores of S. costatum from coastal sediments of the Australian continental shelf. Worthy of comment here is the frequency in the Laguna Madre and Corpus Christi and Aransas Bays of species often associated with fresh water such as Rhopalodia spp. and Epithemia spp. The Species Concept in the Diatomaceae Among the planktonic diatoms, the siliceous skeletons of which are not easily pre­sen-ed, morphology, including cell shape, appendages, number and distribution of chloro­plasts, is used in taxonomy, but even in this case, it is not unusual to find a Chaetoceros chain with terminal cells having characters of two recognized species. This implies that even in this group, the classification is not strictly phylogenetic. The sedimentary and epontic diatoms, on the other hand, have long been classified by their siliceous frustules, the cell contents being destroyed to show the detail of the frustule structure. This has been a great advantage, since the frustules are important evidence in the geological record, and it is possible to homologise fossil and living species. The result of this classification has from the taxonomic point of view been unfortunate in that small differences in the detailed structure of frustules have been considered sufficient to erect new species, and type specimens have been carefully preserved in museums in order to perpetuate them. · As an example, the variable Navicula granulata was considered separate from N. brasili­ensis though intergrades are as common as typical specimens, and there is no doubt that N. brasiliensis is at most an eco-form of N. granulata. Further confusion has arisen from the frequent creation of monogeneric and even monospecific families, the absurdity of which is shown by a recent paper by Wood (1959b) who describes and depicts a cell of which one valve has the characteristics of Coscinodiscus and the other of Asteromphalus -two different families! In Aransas Bay, a diatom cell was found, one valve of which was typical Coscinodiscus and the other Actinocyclus. From this, it would seem that the classi­fication of discoid diatoms with respect to their frustules has no necessary phylogenetic significance and that the "families" of this group are at most a convention. The present classification of the diatoms is, however, useful, and it is not possible to discard it or substitute a more phylogenetic taxonomy, but it is well that we should bear in mind its limitations, and remember that much of the difficulty of identifying some specimens among the large number of described and figured species is due to the uncritical creation of species by many taxonomists. Diatom Species The species will be recorded in alphabetical order. Genus ACHNANTHES Bory, 1822 Frustules usually stipitate, solitary or in short ribbons; valves elliptic or lanceolate, A Study of the Diatom Flora of Fresh Sediments of the South Texas Bays 239 dissimilar, one with and the other without a raphe, the raphe-less valve haYing a pseudoraphe; cells in girdle view often chevron-shaped. 1. Achnanthes biasolettiana (Klitzing) Grunow (Plate 1, Figs, 1, a, b). Grunow (1880, 22), Hustedt (1933, 379, 823). Synedra biasolettiana Klitzing (1884, 63, 3, 22). Valves broad linear-elliptic with blunt, produced ends; rapheless valve with very narrow pseudoraphe, without central area; striae transverse; raphe straight, axial area narrow, central area narrow, strie transverse on raphe valve. Distribution.-Aransas Bay. 2. Achnanthes brevipes Agardh (Plate 1, Fig. 2). Agardh (1824, 1; 1832, 59), Hustedt (1933, 424, 877a-c). Cells usually in short ribbons or solitary, free or attached by a short stipe; frustules in girdle view chevron-shaped, in valve view linear-elliptic with rounded ends and slightly constricted towards the middle; valve surface punctate in transverse and longitudinal rows and also costate, costae separated by a single row of puncta; raphe with a strong central area dilated centrally forming a stauros. Distribution.-Laguna Madre, Aransas Bay, San Antonio Bay. 3. Achnanthes curvirostrum Brun (Plate 1, Figs. 3 a, b). Brun (1895, 16, 84, 85), Hustedt (1937, in A.S.A., 415, 21, 22; 1955, 18, 5, 20, 21). Frustules elliptic-lanceolate with rostrate ends which may be oppositely curved; raphe­less valve with straight pseudoraphe, slightly curved at ends, and transverse, punctate striae; raphe curved at ends, striae transverse on raphe valve. Distribution.-Copano, San Antonio, Matagorda and Galveston Bays. 4. Achnanthesdelicatula (Klitzing) Grunow (Platel,Figs.4a,b). Grunow (in Cleve & Grunow, 1880, 22), Hustedt (1933, 389, 836). Achnanthidium delicatulum Klitzing (1844, 75, 3, 21). Valves elliptic-lanceolate with more or less rostrate ends; rapheless valve with narrow, linear pseudoraphe, raphe valve with straight raphe, narrow axial and small central areas; striae strongly marked, radial, weaker on upper valve. Distribution.-Baffin Bay, Aransas Bay, Copano Bay. 5. Achnanthes exilis Klitzing (Plate 1, Figs. 5 a, b) . Klitzing (1833, 12), Hustedt (1933, 378, 822). Valves linear-lanceolate, tapering evenly from the middle to the acutely rounded ends; rapheless valve with narrow linear pseudoraphe, raphe valve with straight raphe, narrow axial area and small, oval central area; striate coarse, parallel, transverse. Distribution.-Baffin Bay, Aransas Bay, Upper Laguna Madre; Copano, Matagorda, and Galveston Bays; Apalachicola (Florida). 6. Achnanthes hauckiana Grunow (Plate 1, Fig. 6). Grunow (1880, 21), Hustedt (1937, 388, 834). Valves elliptic to elliptic-lanceolate with blunt to acute, slightly produced ends; raphe­less valve with linear to linear-lanceolate pseudoraphe and no central area; raphe valve with straight raphe, narrow axial area, small central area and coarse radial striae. Distribution.-Aransas (Redfish) Bay. 7. Achnanthes hungarica Grunow (Plate 1, Fig. 7). Grunow (in Cleve & Grunow, 1880, 17, 20), Hustedt (1933, 383, 829). Valves lanceloate with rounded ends; raphe valve has a narrow axial area and coarse, transverse striae; rapheless valve with a narrow pseudoraphe, coarse striae and a stauros reaching the margin. Distribution.-Lower Laguna Madre, Copano Bay. 8. Achnanthes lemmermannii Hustedt (Plate 1, Fig. 8) . Hustedt (1933, 390, 837), in A.S.A. (1936, 408, 36-39). Valves elliptic-lanceolate with capitate, blunt ends and almost parallel sides; rapheless valve with narrow pseudoraphe; raphe valve with narrow axial area, equal central area; both valves 'vith coarse, radial striae. Distribution.-Apalachicola (Florida) . 9. Achnanthes longipes Agardh (Plate 1, Fig. 9). Agardh, (1824, 1), Hendey (1951, 42, 1-9, 2, 1-12). Cells in ribbons or solitary, often stipitate with strong, curved stipe; frustules in valve view linear-elliptic, in girdle view chevron-shaped; valve surface with 2 rows of puncta between strong costae; girdle with finely punctate parallel striae. Distribution.-Pensacola Bay (Florida). 10. Achnanthes manifera Brun (Plate 1, Figs. 10 a,b) . Brun (1895, 16, 86, 87), Hustedt (in A.S.A., 415, 20-22). Vah-es elliptic-lanceolate with slightly rostrate ends; raphe valve with straight, narrow pseudoraphe and coarse, punctate striae; lower valve with straight raphe, tapering axial area, stauros becoming diffuse by infusion of striae which are confused in this portion, but fine and parallel in the rest of the valve; a very variable species. Distribution.-Lower Laguna Madre, Matagorda Bay, St. Andrews Bay (Florida). 11. Achnanthes tenera Hustedt (Plate 1, Figs. 11 a,b). Hustedt (1955, 17, 5, 22-25). Vah·es elliptic-lanceolate with acute, subrostrate ends; rapheless valve with narrow pseudoraphe and slightly radiate striae; raphe valve with straight raphe, narrow axial area, smalL at times unequal central area and radiate, punctate striae. Distribution.-Aransas, Baffin, San Antonio, and Matagorda Bays; Pascagoula, (Mis­sissippi) . Florida coast. GenusACTINOCYCLUS Ehrenberg, 1837 Valves circular to elliptical; surface flat at center, sloping to margin; central space usually present, often irregular; pseudo-ocellus at or near margin; surface of valve punctate in radial to fasciculate rows. 12. Actinocyclus octodenarius Ehr. (Plate 1, Fig 12 a). Ehrenberg (1838, 172, 21, 7), Hendey (1937). A. ehrenbergi Ralfs, 1861 in Hustedt (1927, 525). Cells solitary, discoid; central space round or irregular with scattered granules; sur­ face flat for about half diameter, then rounded; divided into wedges by hyaline inter­spaces; markings granular in radial, interrupted fasciculate rows of several orders; hya­line interspaces may' be prominent near border; circular pseudonodule near margin. Distribution.-Upper Laguna Madre; Copano, San Antonio and Matagorda Bays. v. ral,fsii (W. Smith) Hustedt (Plate 1, Fig. 12 b). Hustedt (1927, 528, 299) . Eupodiscus ralfsii W. Smith, 1856. Rows of puncta of several orders, the shorter ones alternating and terminating in hyaline areas. Distribution.-Pensacola Bay (Florida). v. sparsa (Gregory) Hustedt (Plate 1, Fig. 12 b). Hustedt (1927, 528, 300). Eupodiscus sparsus Gregory (1857, 710). Puncta in a fasciculate arrangement, only a few reaching the hyaline central area. Distribution.-Pascagoula (Mississippi). v. tenella (Brebisson) Hustedt (Plate 1, Fig. 12 c). Hustedt (1927, 530; 300), Eupodiscus tenellus Brebisson (1854, 257, 1, 9) .. Valves flat, thin walled; puncta sparse, radial. Distribution.-Laguna Madre. Genus ACTINOPTYCHUS Ehr., 1839 em. van Heurck, 1890 Frustules disco id; with undulate valve surface; valves with six or more alternately raised and depressed sectors, areolate on outer, punctate on inner surface; central area usually hyaline, circular to polygonal. 13. Actinoptychus campanulifer A. Schmidt (Plate 1, Fig. 13). A:S.A. (1875, 29, 13-15) . Valves small, discoid with 6 sectors; surface coarsely areolate, areolae larger propor· tionally than those of A. senarius (A. undulatus); inner layer coarsely punctate; central area about 1h valve diameter. Distribution.-Upper Laguna Madre, Aransas Bay, Matagorda Bay, Copano Bay, Galveston Bay. 14. Actinoptychus senarius (Ehr.) Ehr. Ehrenberg (1843, 6, l , 1, 27), Hendey (1951, 32). Actinocyclus senarius Ehr. (Plate 1, Fig. 14). Ehr. (1838, 172, 21, 6). Actinoptychus undulatus Kiitzing (1844, 132, 1, 24). Frustules discoid; valve with 6 sectors; surface coarsely areolate, with larger areolae towards margin and inner layer of puncta radiating; each sector with a short spine under margin. Distribution.-Upper Laguna Madre, Aransas Bay, Matagorda Bay, Galveston Bay. 15. Actinoptychus taeniatus Hustedt (Plate 1, Fig. 15). Hustedt (1955, 7, 52, 1, 2). Valves circular, undulate with 6 sectors and large, hyaline central space; surface coarsely and irregularly areolate; inner layer punctate with puncta in straight or slightly diverging rows and 2 systems of oblique rows; deeper sectors with coarser puncta ; proc· esses at middle of upper sectors on valve margins. Distribution.-Upper Laguna Madre, Aransas Bay, Matagorda Bay, Galveston Bay. 242 A Study of the Diatom Flora of Fresh Sediments of the South Texas Bays Genus AMPHIPRORA Ehrenberg, 1843 Frustule twisted on the longitudinal axis, constricted in the middle; girdle complex, striate; valves lanceolate; raphe confined within a sigmoid keel or valve extension; striate transverse, punctate. 16. Amphiproraalata (Ehr.) Kiitzing (Platel,Figs.16a,b). Kiitzing, (1844, 107, 3, 63). Navicula alata Ehrenberg (1840, 212). Cells solitary or in short ribbons; frustules in valve view linear with acute apices, in girdle view constricted and twisted in the middle; axial area raised to form a sigmoid keel bearing the raphe; valve striate, keel coarsely punctate; girdle bands multiple, striate. Distribution.-Upper Laguna Madre, Aransas Bay. 17. Amphiprora gigantea Grunow (Plate 1, Fig. 17). Grunow (1860, 568). Cleve (1894, 18, 1, 6). Frustule strongly constricted, and twisted; keel with hyaline margin, broader towards ends, junction line uniformly arcuate; keel puncta in oblique rows, striae curyed, di­vergent from central nodule; raphe strongly sigmoid; girdle with numerous bands. Distribution.-Upper Laguna Madre, Aransas Bay, Matagorda Bay, San Antonio Bay, numerous. Genus AMPHORA Ehrenberg, 1840 Valves asymmetrical along longitudinal axis and cuneate in transverse section; raphe excentric, often curved. 18. Amphora acuta Gregory Gregory (1957, 21, 524) . Valves lunate with acute ends; ventral margin straight, ventral side very narrow: cen· tral nodule dilated to a stauros; striae transverse, punctate. v. arcuata (A.S.) Cleve (Plate 2, Fig.18). Cleve ( 1895, 128) . A. arcuata A.S.A. (1875, 26, 26-29). Dorsal margin strongly arcuate with rostrate ends, ventral margin slightly to strongly biarcuate; raphe marginal on ventral margin, transverse, punctate coarse striae. Distribution.-Aransas Bay, Upper Laguna Madre, St. Andrews Bay (Florida). 19. Amphora angularis Gregory (Plate 2, Fig. 19). Gregory (1855, 39, 3, 6), A.S.A. (1875, 25, 83). Frustules in girdle view elliptic-lanceolate with constricted middle and bluntly pro· duced ends; valves with arcuate dorsal and straight ventral margins, raphe closer to latter; striae transverse, punctate, somewhat coarse. Distribution.-Upper Laguna Madre, San Antonio Bay. 20. Amphora angusta Gregory (Plate 2, Fig. 20). Gregory ( 1857, 510, 12, 66). Cleve ( 1895, 135). Cells solitary; frustules in girdle view linear-elliptic, m valve view arcuate with straight ventral margin; raphe straight, near ventral margin; striae transverse, marginal striae more distinct. Distribution.-Laguna Madre, Corpus Christi and Aransas Bays; St. Andrews Bay (Florida). 21. Amphora arenaria Donkin {Plate 2, Fig. 21). Donkin (1858, 31, 3, 16), A.S.A. (1875, 40, 8-10) , Boyer (1927, 269). Frustules rectangular with rounded ends; girdle without longitudinal lines, hyaline; valves linear, ends rounded, ventral margin sinuate or biarcuate; raphe biarcuate with recurved apices; striae very fine, more marked on dorsal margin. Distribution.-Upper Laguna Madre, Aransas Bay {rare). 22. Amphora aspera Petit ? (Plate 2, Fig. 22). Petit (1877, 19, 4, 9), Cleve {1895, 128, 3, 22). Valves semi-lanceolate, dorsal margin arcuate, slightly undulate; beaked ends; ventral margin undulate, slightly gibbous centrally; striae on dorsal side punctate, forming undulate longitudinal lines. Distribution.-Upper Laguna Madre. 23. Amplwra capensis A.S. (Plate 2, Fig. 23). A.S.A. (25, 49, 50), Cleve ( 1895, 115) . Frustules elliptical with broad, rostrate ends; valves arcuate dorsal margin convex with slightly rostrate ends, ventral margin concave near ends; raphe sinuate; stauros present; surface with coarse, transverse striae. Distribution.-St. Louis Bay, Biloxi (Mississippi). 24. Amphora cofjaeiformis (Agardh) Kiitzing (Plate 2, Fig. 24 a, b). Kiitzing (1844, 108), A.S.A. (1875, 26, 56-58), Boyer (1927, 260). Frustules elliptic-lanceolate with produced ends, truncate; girdle with several longi­tudinal divisions; valves strongly arcuate on dorsal, straight or concave on ventral mar­gins, rostrate or capitate; raphe near ventral margin; striae fine on dorsal side. Distribution.-On Diplanthera in Laguna Madre, Corpus Christi Bay, Aransas Bay {at times dominant), Matagorda Bay (rare); Baffin Bay, Copano Bay. 25. Amplwra decussata Grunow {Plate 2, Fig. 25). Grunow { 1867, 23), Cleve ( 1895, 128, 4, 1) . Frustules elliptical, truncate; girdle with numerous divisions; striate; valves with arcuate dorsal, and straight or almost straight ventral margins, ends acute; raphe close to ventral margin; stauros narrow; pun eta forming slightly undulating longitudinal and transverse rows. Distribution.-Lower Laguna Madre. 26. Amphora delphinea Bailey (Plate 2, Fig. 26). Bailey (1861, 1, 1) , A.S.A. {1875, 40, 25-27), Cleve (1895, 134), Boyer (1927, 270). Frustule rectangular-elliptic, may be gibbous in the middle; valves linear to lunate with obliquely rounded ends, central nodule forming a stauros; raphe sinuate, striae transverse, fine. Distribution.-St. Louis Bay (previous record from Pensacola). 244 A Study of the Diatom Flora of Fre$h Sediments of the South Texas Bars 27. Amphora dubi.a Gregory (Plate 2, Fig. 27 a, h). Gregory (1857, 514, 13, 76), Cleve (1895, 102, 4, 5, 6). Frustules in girdle view sub-elliptic; valves with arcuate dorsal and straight to convex ventral margins; raphe straight or slightly curved; striae traru;verse, punctate. Distrihution.-L"pper Laguna Madre, Corpus Christi Bay, Aransas Bay, Matagorda Bay, Galveston Bay. 28. Amphora egregi.a A.S. (Plate 2, Fig. 28 a, h). A.S.A. (1875, 28, 13-15), Boyer (1927, 257). Frustules in girdle view elliptic with truncate ends; valves lunate with rounded, retrorse ends, ventral margin hiarcuate, gibbous centrally, raphe hiarcuate; surface with a series of coarse traru;verse striae; ventral side with a row of strong radial striae; girdle with 2-4 rows of rounded puncta. Distribution.-Araru;as Bay, Laguna Madre. 29. Amphora graeffii {Grunow) Cleve (Plate 2, Fig. 29). Cleve (1895, 113) . ­ A. graelfii var. Grunow (in A.S.A., 25, 40). Valves with arcuate dorsal and straight to slightly concave ventral sides, ends slightly rostrate; raphe straight to slightly biarcuate; striae almost parallel to transwrse axis with a ridge between dorsal and ventral margiru;. Cleve (Le.) considers that this species is close to if not identical with A. grevilleana Gregory, 1857. Distribution.-Laguna Madre, Araru;as Bay. 30. Amphora granulata Gregory (Plate 2, Fig. 30 a, b). Gregory (1857, 21, 525) , Cleve (1895, 123). Frustules in girdle view linear-elliptic, in valve view with arcuate dorsal and straight ventral margins and capitate ends; raphe straight, close to wntral margin; striae coarse, transverse. Distribution.-L'pper Laguna Madre, Baffin, Corpus Christi, Aransas and San Antonio Bays. 31. Amphora hyalina Kiitzing (Plate 2, Fig. 31). Kiitzing (1844, 108, 30, 18) , Cleve (1895, 126, 127), Boyer (1927, 264). Frustules in girdle view sub-rectangular with rounded corners; vah·es with com·ex dorsal and straight ventral margins and acute ends; raphe straight, striae fine. Distribution.-Lpper Laguna Madre, Aransas and Copano Bays; Florida. 32. Amphora javanica A.S. (Plate 2, Fig. 32 a, b). A.S.A. (1875, 27, 27, 30-33), Cleve (1895, 104). Frustules in girdle view rectangular with evenly rounded ends; vakes with arcuate dorsal and straight ventral margins; raphe biarcuate, almost median; striae coarse, interrupted to form irregular, wavy lines, equally evident on dorsal and ,-entral sides of the raphe. Distribution.-Upper Laguna Madre, Aransas Bay. 33. Amphora laevis Gregory (Plate 2, Fig. 33 a, b). Gregory (1857, 514, 74), Boyer {1927, 268). Frustules membranaceous, rectangular in girdle view, with slightly constricted middle and rounded, sub-truncate ends; girdle zone with numerous intercalary bands; valves with arcuate, slightly notched and slightly sinuate ventral margins and a marked stauros; striae evident, transverse. · Distrihution.-Upper Laguna Madre, Aransas Bay. 34. Amphora mexicana A.S. (Plate 2, Fig. 34) . A.S.A. (1875, 27, 47, 48) , Cleve (1895, 105). Frustules elliptic, truncate in girdle view; in valve view lunate with slightly concave ventral margin; raphe hiarcuate, axial area not distinct; longitudinal line near margin on dorsal side. Distrihution.-Upper Laguna Madre; Baffin, Aransas and Espiritu Santo Bays. 35. Amphora obtusa Gregory (Plate 2, Fig. 35 a, h). Gregory (1857, 12, 60) , A.S.A. ( 1875, 40, 4-7, 11-13), Cleve (1895, 131). Frustules rectangular in girdle view, with rounded ends and may he slightly con­stricted in the middle; girdle with a few intercalary hands; valves linear with rounded ends, arcuate dorsal and straight ventral margins; raphe hiarcuate, striae faint, trans­verse. Distrihution.-Upper Laguna Madre, Aransas Bay. 36. Amphora proteus Gregory (Plate 2, Fig. 36 a-c). Gregory ( 1857, 518, 81), A.S.A. (27, 3), Cleve ( 1895, 103) . Frustules variable, in girdle view elliptic to oblong with rounded ends, narrow to broad; valves lunate, acute, sometimes arcuate with straight ventral margin; raphe biarcuate; central area variable; striae transverse punctate. Distribution.-Lower and Upper Laguna Madre, Aransas, Corpus Christi, Matagorda and Galveston Bays; Pensacola and St. Andrews Bay (Florida). 37. Amphora robusta (Gregory) (Plate 3, Fig. 37). Gregory (1857, 516, 13, 79) , Cleve ( 1895, 103). Frustules elliptic; valves with strongly arcuate dorsal, and slightly sinuate or straight ventral margins; raphe nearly central with marked central area and tapering axial area; surface with radial costae. Distribution.-Baffin Bay, Lower Laguna Madre. 38. Amphora spectabilis (Gregory) (Plate 3, Fig. 38). Gregory (1857, 516, 30 a-c) , Cleve (1895, 132). Frustules in girdle view oblong with rounded ends; girdle zone with numerous striate divisions; valves arcuate, ends rounded on dorsal, slightly capitate on ventral margin; raphe hiarcuate; striae frequently branched, finer on ventral side of raphe. Distribution.-Corpus Christi Bay (dominant on occasion). 39. Amphora turgida Gregory (Plate 3, Fig. 39). Gregory (1857, 510, 63) , Wood (1961, 690, 54, 147). Frustule nearly orbicular with short, square, produced apices ; valves nearly semi­circular to elliptical with straight or concave ventral margins and capitate apices ; nodules conspicuous, raphe close to ventral margin; striae radiate. Distrihution.-Laguna Madre, Baffin Bay, Aransas Bay, Matagorda Bay, Florida coast. 40. Amphora terroris Ehrenberg (Plate 3, Fig. 40 a, b). Ehrenberg (1853, 526), A.S.A. (1875, 25, 17-19, 32-34), Boyer (1927, 262). A. cymbifera Gregory (1857, 526). Frustules elliptical, ends produced, truncate; girdle with intercalary bands; valves with arcuate dorsal, concave ventral margins, capitate; raphe close to ventral margin; striae indistinct! y punctate. Distribution.-Aransas Bay, Redfish Bay. 41. Amphora weissflogii A.S. (Plate 3, Fig. 41 a, b). A.S.A. <1875, 25, 58), Cleve (1895, 116), Boyer (1927, 259). Frustules rectangular indented in the middle, border narrow, hyaline girdle with four intercalary bands; valves with arcuate dorsal margin, slightly indented in the middle, ventral margin slightly gibbous; ends of valves rostrate to capitate, slightly retrorse; central nodule forming stauros; raphe close to ventral margin; striae transverse. Distribution.-Aransas Bay, Matagorda Bay; St. Andrews Bay (Florida). 42. Amphora sp. 1. (Plate 3, Fig. 42). Valve with arcuate dorsal margin, ventral margin slightly constricted near apices; raphe slightly arcuate, median; striae faint, transverse. Distribution.-Matagorda Bay. 43. Amphora sp. 2. (Plate 3, Fig. 43). Valves with arcuate dorsal and straight ventral margins, ends slightly rostrate, raphe slightly biarcuate; stauros present; striae somewhat coarse, radial, clearly punctate. Distribution.-Aransas Bay. Genus ASTEROMPHALUS Cells discoid, valves circular to oval with raised, hyaline rays separating punctate sectors, one ray being double; central area hyaline. 44. Asteromphalus flabellatus (Brebisson) Greville (Plate 3, Fig. 44). Greville ( 1869, 160), Boyer ( 1927, 74). Spatangidium flabellatum Breb. ( 1857, 297) . Valves oval; hyaline area about half valve diameter; segments areolate, connected by straight rays; hyaline rays about 6, strong. Distribution.-Corpus Christi Bay, Aransas Bay. Genus AULISCUS Ehr., 1843 Frustules cylindrical; girdle finely punctate; valves circular to elliptic, central area hyaline; two or three sub-marginal processes, which are short, cylindrical; surface of valve granulate or linear. 45. Auliscus retU:ulatus Greville (Plate 3, Fig. 45). Greville (1863, 46, 2, 10), Hustedt (1929, 513, 288). Frustules discoid with broadly elliptic, almost circular valves; rounded central area, ribs roughly concentric from central area to the 2 processes, and radial in between, united by reticulate cross ribs, and radial between the raised areas of the valves. Distribution.-Upper Laguna Madre, Aransas Bay, Matagorda Bay. Genus BACILLARIA Valves linear with tapering ends; raphe on punctate keel as in Nitzschia; the genus is characterized by a peculariar lateral motion of the cells with respect to each other, the colony varying from palisade to arrow-head, to z-shaped. 46. Bacillaria paxillifer (0. F. Miiller) Nitzsch (Plate 3, Fig. 46). Nitzsch (1817, 75), Crosby & Wood (1959, 40, 8, 119). Vibrio paxillifer O.F.M. ( 1786, 54). Also known as Nitschia paradoxa, Bacillaria paradoxa. Cells colonial, arranged in palisade formation, able to slide laterally with respect to each other with a characteristic motion; frustules linear with tapering ends; keel puncta strong, striae transverse. Distribution.-Pascagoula (Mississippi). Genus BACTERIASTRUM Cells in straight chains; joined by marginal extensions broken by several apertures and with several to numerous setae at right angles to the chain axis. 47. Bacteriastrum varians Lauder (Plate 3, Fig. 47). Lauder (1864, 8, 3, 1-6), Allen & Cupp (1935, 133, 48). Cells in straight chains; frustules nearly equal in width and length; setae 10-26, at right angles to chain axis; apertures small; terminal setae with fine spines in spiral rows. Distribution.-Pensacola (Florida), common in the sediments. Genus BIDDULPH/A Gray, 1831 Cells in chains or solitary; when in chains, united by processes; frustules usually more or less rectangular in girdle view, elliptical or elliptic-crenate in valve view; processes at each angle and two spines also frequently present; surface usually reticulate, or punctate. 48. Biddulphia aurita (Lyngbye) Brebisson (Plate 3, Fig. 48). Brebisson ( 1838, 12) . Cells solitary, in straight or zig-zag chains, frustules in valve view lanceolate; processes inflated at base, tapering to ends; valves with small radial puncta and small lateral spines in convex central area; girdle sharply differentiated from valve; plastids numerous, reinform to elliptic. Distribution.-Aransas and Matagorda Bays. 49. Biddulphia levis Ehrenberg (Plate 3, Fig. 49). Ehrenberg (1843, 122) , Hustedt (1929, 852, 506). Frustules solitary or in short chains; cylindrical, longer than broad; valves flat or convex with deep mantle; processes much reduced, often only as hyaline eyes at valve corners; valves finely areolate in diagonal rows; small spinelets on valve surface. Distribution.-Matagorda Bay; Fort Pike (Mississippi). 50. Biddulphia longicruris Greville (Plate 3, Fig. 50) . Greville (1859, 163, 8, 10), Cupp (1943, 154, 111). Cells in girdle view cylindrical with rounded valves having two long, tapering proc­ 248 A Study of the Diatom Flora of Fresh Sediments of the South Texas Bays esses oblique to the valves and two long-curved spines much closer to center of valve, valve constricted above girdle; girdle and valves reticulate. Distribution.-Aransas Bay. 51. Biddulphia mobiliensis (Bailey) Grunow (Plate 3, Fig. 51). Grunow (in van Heurck 1880-85, 103a), Boyer (1901, 698; 1927, 122). Zygoceros (Denticella) mobiliensis Bailey (1851, 40). Cells solitary or united by spines; valves elliptic-lanecolate; surface convex with flat center, separated from rest of valve by a slightly elevated ridge which extends in two more or less sigmoid lines from one process to the other; on opposite sides of the central por­tion is a small, conical projection from which extend one or two long, slender spines; processes slender, capitate; valve surface delicately punctate. Distribution.-Upper Laguna Madre, Aransas Bay, Matagorda Bay. 52. Biddulphia pulchella Gray (Plate 3, Fig. 52). Gray (1821, 1, 294), Hendey (1951, 34). Cells solitary or in short chains; frustules cylindrical in girdle view, elliptical in valve view; valves with undulating sides divided by costae into 3 or more sections; ends with large, globular or subconical processes, finely porulate; valve surface between costae coarsely areolate, areolae concentric in center, concentrically with processes towards margin; in girdle view aerolae with a longitudinal and transverse arrangement; girdle punctate, striate; plastids numerous. Distribution.-Aransas Bay. 53. Biddulphia subaequa (Kiitzing) Ralfs (Plate 3, Fig. 53). Ralfs (in Pritch 1861, 848), Hustedt (1927, 849, 503). Odontella subaequa Kiitzing ( 1844, 137, 18, 8, 4-5). Frustules longer than broad; valves dome-shaped, with short, blunt, slightly flaring processes; valve surface with short spinelets and fine, more or less radial areolae. Distribution.-Upper Laguna Madre, Matagorda Bay, Pascagoula (Mississippi). 54. Biddulphia sp. (Plate 3, Fig. 54). Frustules with rectangular girdle and tapering valves, the latter with upper portion oblique to transverse axis; upper part of valve with coarse, transverse areolae, mantle with finer oblique areolae; small blunt processes and long spines at valve ends. Distribution.-Matagorda Bay. Genus CALONEIS Cleve, 1894 Valves convex, linear to linear lanceolate with transverse, smooth or punctate striae crossed by one or more longitudinal lines parallel to margins. 55. Caloneis formosa (Gregory) Cleve (Plate 3, Fig. 55). Cleve (1894, 57). Navicula formosa Gregory (1856, 42, 6). Valves narrow lanceolate with obtuse ends; axial and central areas forming an irregu­larly lanceolate space, usually dilated unilaterally in the middle; striae almost paralleL radiate at ends; longitudinal lines median. Distribution.-Aransas Bay; Pascagoula (Mississippi). 56. Caloneis latiuscula (Kiitzing) Cleve (Plate 3, Fig. 56). Cleve (1894, 61), A.S.A. (1911, 271, 1, 2), Cleve-Euler (1953, 1134b). N avicula latiuscula Kiitzing ( 1844, 93, 5, 40) . Valves elliptic to lanceolate, axial and central areas forming an irregularly lanceolate space; striae parallel, finely punctate, of varying length; longitudinal lines marginal. Distribution.-Aransas Bay; Pensacola (Florida) . 57. Caloneis liber (W. Smith) Cleve (Plate 4, Fig. 57). Cleve ( 1894, 26, 54), A.S.A. (1881, 50, 16-18), Boyer (1927, 310). Navicula liber W. Smith (1863, 48) . Valves oblong, elliptic with rounded ends; axial area very narrow; central area small, circular; striae parallel, transverse, radial at ends of valve; longitudinal lines median, may be single or double. Distribution.-Lower Laguna Madre, Aransas Bay. 58. Caloneis permagna (Bailey) Cleve (Plate 4, Fig. 58) . Cleve (1894, 59), A.S.A. (1911, 271, 30, 31), Boyer (1916, 82, 21, 1; 1927, 313), Cleve· Euler ( 1953, 1120) . Pinnularia permagna Bailey ( 1850, 40, 2, 28, 38) . Valves rhombic-lanceolate, margins sometimes slightly triundulate; axial and central areas forming an irregularly lanceolate space; longitudinal lines broad or double, median, striae radial. Distribution.-Corpus Christi Bay. 59. Caloneis probabilis (A.S.) Cleve (Plate 4, Fig. 59). Cleve ( 1894, 56) . N avicula probabilis A.S.A., ( 50, 46-48) . Valves linear-elliptic with rounded but slightly produced ends; raphe sinuate; axial area narrow, central area small; striae coarse, punctate, perpendicular to raphe, longi­tudinal lines double. Distribution.-Aransas Bay. Genus CAMPYLOD/SCUS Ehrenberg, 1841 Valves orbicular to cordate, saddle-shaped, the frustule consisting of two saddle-shaped valves at right angles to each other, girdle varying in shape according to position; raphe marginal; valve surface with radial costae and a hyaline central space or a central line. 60. Campylodiscus biangulatus Greville (Plate 4, Fig. 60) . Greville (1863, 4, 2), A.S.A. (1875, 14, 18-22). Valves heart-shaped or sub-circular, strongly convolute; costae strong, bifurcate near margin, reaching linear-ovate median space; costae very strong in valve view. Distribution.-Laguna Madre. 61. Campylodiscus echeneis Ehr. (Plate 4, Fig. 61) . Ehrenberg (1841, 206), A.S.A. (1886, 54, 36), Boyer (1916, 130, 37, 5; 1927, 552). Valves circular; costae indistinct, short, marginal; surface with rows of round or elongate puncta, unequal and at irregular intervals, converging towards a lanceolate median space. Distribution.-Pensacola Bay, Florida. 62. CamVJlodiscus hibemicus Ehr. (Plate 4, Fig. 62). Ehrenberg (1845, 54) , A.S.A. (1876 55, 9-14), Boyer (1916, 130, 37, 5; 1927, 555). Valves subcircular, with cruciform median space; highly convolute; in semi-girdle view cordate with radial ribs extending to median space. Distribution.-Upper and Lower Laguna Madre. Genus CAMPYLOSIRA Grunow, 1882 Frustules in ribbons, united by middles of valves; valves with unequally gibbous mar­gins; punctate. 63. Campylmira cymbelliformis (A.S.) Grunow (Plate 4, Fig. 63). Grunow (in van Heurck 1880--85, 45, 43), Hustedt (1929, 128, 650). Frustules in ribbons, united by the middles of the valves; in girdle view with undulate margins, gibbous in the middle, and swollen at the ends; valves rostrate with unequally' gibbous margins the dorsal being more convex; valves strongly punctate. Distribution.-Lower Laguna Madre, Corpus Christi, Aransas, Copano Bays. Genus COCCONEIS Ehrenberg, 1935 Valves elliptical dissimilar, epontic; one valve with raphe, the other differently marked and with a pseudoraphe, frustule usually with a rim or annulus. 64. Cocconeis apiculata A.S. (Plate 4, Fig. 64). A.S.A. (1894, 198, 30), Boyer (1927, 251). ' Frustules elliptic with apiculate ends; rapheless valve with punctate striae parallel, transverse; pesudoraphe narrow. Distribution.-Aransas Bay. 65. Cocconeis costata Gregory {Plate 4, Fig. 65). Gregory (1855, 39, 4, 10), Hustedt (1923, 332, 785). Valves elliptic; rapheless valve with double rows of puncta between the radial striae; pseudoraphe narrow; raphe valve with tapering striae, a narrow rim; straight raphe and narrow areas, often with a narrow stauros. Distribution.-Lower Laguna Madre. 66. Cocconeis disculoides Hustedt (Plate 4, Fig. 66 a, b). Hustedt (1955, 17, 5, 8-11; 7, 8). Valves elliptic; rapheless valve with a narrow, lanceolate pseudoraphe semi radiate striae, which are coarse, interrupted, forming several longitudinal lines; raphe valve with straight raphe and narrow axial area; striae punctate, only identifiable as such in the marginal zone, otherwise consisting of fine puncta. Distribution.-Aransas Bay. 67. Cocconeis disculus (Schumann) Cleve (Plate 4, Fig. 67). Cleve (1895, 172), Hustedt (1933, 345, 799). N avicula disculus Schumann ( 1864, 21, 2, 23) . Valves elliptic to elliptic·lanceolate; rapheless valve with coarse, interrupted striae giving the effect of a series of dashes; pseudoraphe lanceolate; raphe valve finely striate, striae radial, raphe straight with very narrow areas. Distribution.-Upper and Lower Laguna Madre, Baffin Bay, Aransas and Matagorda Bays. 68. Cocconeis distans Gregory (Plate 4, Fig. 68). Gregory (1857, 18, 1, 23) , Hustedt (1933, 343, 797) . Valves elliptic; rapheless valve with finely punctate margin and distant radial ribs with several irregular puncta therein; pseudoraphe linear; raphe valve with regularly punc­tate, radial striae; raphe straight; areas small. Distribution.-Upper and Lower Laguna Madre, Aransas, Capano and Matagorda Bays. 69. Cocconeis heteroidea Hantzsch (Plate 4, Fig. 69). Hantzsch (1863, 1, 21), Boyer (1927, 248) , Hustedt (1933, 356, 811) . Cells solitary, usually attached; valves circular to elliptic; rapheless valve with fine radial striae interrupted by hyaline an~as and crossed by curved longitudinal lines; raphe valve with strongly marked radial striae; central nodule indistinct; raphe sig­moid, margin hyaline. Distribution.-Lower Laguna Madre. 70. Cocconeis maxima (Grunow) Perag. (Plate 4, Fig. 70). Peragallo (1897, 18, 3, 1-4), Hustedt (1933, 335, 789) . Mastogloia maxima Grunow (1863, 516, 4, 1). Cocconeis lorenziana A.S.A. (1894, 191, 28-34). Valves ellip~ic; rapheless valve with short marginal ribs, which submarginally are separated by a double row of puncta and more centrally consist of rows of puncta; pseudo­raphe lanceolate; raphe valve with straight raphe, narrow areas, fine, punctate, radial striae not reaching margin, which is hyaline, with an inner ring of fine striae separated by puncta. Distribution.-Lower Laguna Madre. 71. Coccon'!is pensacolae A.S. (Plate 4, Fig. 71 a, b). A.S.A. (1894, 192, 4 a-f). Valves elliptic; central area of rapheless valve elliptic, wide; striae marginal, punc­tate, radiate; raphe valve with straight raphe, fine, marginal striae and wide, elliptic central area. Distribution.-Lower Laguna Madre, Aransas and San Antonio Bays; Pensacola, St. Andrews Bay (Florida). 72. Cocconeis placentula Ehr. (Plate 4, Fig. 72). Ehrenberg (1838, 194), Boyer (1916, 57, 16, 29; 1927, 244), Hustedt (1933, 347, 802). Valves elliptical; rapheless valve clearly punctate in radial striae forming zig-zag longitudinal lines; pseudoraphe narrow, linear; raphe valve with narrow raphe and axial area, striae fine, radial, punctate; loculi rudimentary. Distribution.-Laguna Madre; Baffin Bay, Aransas Bay, Matagorda Bay, St. Andrews Bay (Florida). 73. Cocconeis scutellum Ehr. (Plate 4, Fig. 73 a). Ehrenberg (1838, 194), Hustedt (1931, 337, 790). Cells epiphytic, attached, solitary; frustule in valve view broadly elliptic; rapheless valve with coarse radial puncta and marked pseudoraphe, finely punctate at margin with puncta in rows; raphe valve with straight raphe, small central area, finely radially striate with broad marginal annulus. Distribution.-Laguna Madre, Baffin, Corpus Christi, Aransas and Matagorda Bays; St. Andrews Bay (Florida). v. stauroneiformis W. Smith (Plate 4, Fig. 73 b). W. Smith ( 1853, 30, 34). Central area of raphe valve forming a stauros reaching the margin. Distribution.-Lower Laguna Madre, Corpus Christi and Aransas Bays. 74. Cocconeis sp. (Plate 4, Fig. 74). Valves elliptical; pseudoraphe sigmoid ex centric, narrow; striae coarse, punctate, radial. Raphe valve unknown. Distribution.-Laguna Madre. Genus COSCINODISCUS Ehrenberg, 1838 Frustules cylindrical, usually solitary; valves circular or elliptic, rarely reniform; surface areolate or punctate; central area present or absent; central rosette of larger cells may occur. 75. Coscinodiscus argus Ehr. (Plate 5, Fig. 75) . Ehrenberg ( 1829, 39), Kolbe ( 1954, 28). Frustules discoid; valves with a small, angular central space; areolate; areolae larger near center, decreasing, increasing and decreasing again to margin. Distribution.-Upper Laguna Madre, Corpus Christi, Aransas, and Matagorda Bays. 76. Coscinodiscus asteromphalus Ehr. (Plate 5, Fig. 76). Ehrenberg (1844, 77),Boyer (1916,23,2, 16; 1927,56). Valves convex with a small central space surrounded by a rosette of large, polygonal cells from which radiate hexagonal areolae increasing to about halfway to margin, then decreasing. Distribution.-Aransas, Matagorda and Galveston Bays; Lake Pontchartrain (Louis­iana). 77. Coscinodiscus blandus A.S. (Plate 5, Fig. 77). A.S.A. ( 1886, 59, 35). Valves almost flat; areolae coarse, irregularly arranged, no central area or rosette. Distribution.-Pensacola Bay (Florida), Type loc. Gulf of Mexico (A.S.). 78. Coscinodiscus concavus Gregory (Plate 5, Fig. 78). Gregory (1857, 31, 500), Boyer (1927, 45}. Cells solitary; valves nearly flat; central space absent; areolae of constant size, ir­regular in center but somewhat concentric near margin. Distribution.-Laguna Madre, Baffin, Aransas, San Antonio, Matagorda and Galveston Bays. 79. Coscinodiscus decrescens Grunow (Plate 5, Fig. 79). Grunow (in A.S.A. 1878, 61, 7-10), Hustedt (1927, 430, 233}. Cells with convex valves, strongly areolate, areolae much larger in the center than at the periphery; without the deep margin of C. marginatus. Distribution.-Matagorda and Galveston Bays; Pascagoula (Mississippi}. 80. Coscinodiscus divisus Grunow (Plate 5, Fig. 80). Grunow (1878, 125), Rattray (1889, 499), Hustedt (1928, 409, 218). Vah-es with irregularly radiating fascicules of areolae arranged in irregular orders, with an irregular central rosette. Distributlon.-Matagorda and Galveston Bays. 81. Coscinodiscus elegans Greville (Plate 5, Fig. 81) . Greville ( 1866, 3, 1, 6) , A.S.A. ( 58, 7; 163, 10) , Boyer ( 1927, 59) . Valws with rows of coarse puncta radiating from the margin to the center and a de­pressed central area about 1h diameter of valve, containing scattered to radial puncta. Distribution.-Corpus Christi Bay. 82. Cosdnodiscus excentricus Ehr. (Plate 5, Fig. 82). Ehrenberg (1840, 146), Hustedt (1927, 388, 201). Cells diEcoid; valves flat with narrow margins, having spinules in an irregular circle; areolae in slightly curved, nearly parallel rows, but with a varying arrangement which may differ on each valve; no obvious central area or rosette. Distribution.-Upper Laguna Madre, Corpus Christi, Aransas, Copano, Matagorda and Galveston Bays. 83. Coscinodiscus kuetzingii A.S. (Plate 5, Fig. 83). A.S.A. <1878, 57, 17, 18), Hustedt (1927, 398, 209). Frustules drum-shaped, flat; valves areolate, areolae decreasing slightly from center to margin, arranged in fasciculae giving a V formation and a secondary arrangement con­ sisting of a series of intersecting curves. Distribution.-Aransas Bay. 84. Coscinodiscus lineatus Ehr. (Plate 5, Fig. 84). Ehrenberg I 1838, 129, 37) , Hustedt ( 1928, 393, 204). Frustules discoid; valves flat with hexagonal areolae arranged in rows in 3 directions at 120° angles; no rosette or central area; irregular forms intergrade with a number of other species. Distribution.-Upper and Lower Laguna Madre, Aransas, Copano, San Antonio, Mata­gorda and Galveston Bays; Apalachicola ( Flordia). 85. Coscinod'iscus moelleri A.S. (Plate 5, Fig. 85). A.S.A. ( 1878, 59, 17), Hustedt ( 1928, 395, 206). Valves convex, areolate; areolae diminishing from center to margin in an arcuate­ tangential arrangement; small papilla in center. Distribution.-Aransas, Copano, and Matagorda Bays. 86. Coscinodiscus marginatus Ehr. (Plate 5, Fig. 86). Ehrenberg (1841, 142), Hustedt (1927, 416, 223). Valves flat, convex at margin; surface strongly areolate, areolae hexagonaL diminish­ing to margin, internal pores usually obvious; no rosette or central area; margin with strongly marked, radiate structure. Distribution.-Aransas, San Antonio, Matagorda and Galveston Bays. 87. Coscinodiscus nodulifer A.S. (Plate 5, Fig. 87). A.S.A. (1878, 59, 20-23), Hustedt (1928, 426, 229). Frustules discoid; valves Hat; surface coarsely areolate, usually without specific ar· rangement, but occasionally radial; a small central area present with a small papilla or nodule. Distribution.-Laguna Madre, Baffin, Aransas, Copano and Galveston Bays. 88. Coscinodiscus oculus iridis Ehr. (Plate 5, Fig. 88). Ehrenberg (1841, 147), Hustedt (1927, 454, 252). -Cells discoid; valves slightly concave; hyaline area may be pre~ent; rosette usually large, areolae large, refractile, somewhat radial and in two intersecting excentric curved rows; marginal cells small. Distribution.-Matagorda Bay. 89. Coscinodiscus radiatus Ehr. (Plate 5, Fig. 89). Ehrenberg (1840, 148, 3, 1), Hendey (1937, 250). Frustules discoid; valves flat with polygonal areolae decreasing in size to margin; no rosette or central area. Di~tribution.-Upper Laguna Madre, Corpus Christi, Aransas, San Antonio, Matagorda and Galveston Bays; Pascagoula (Mississippi). 90. Coscinodiscus rothii (Ehr.) Grunow (Plate 5, Fig. 90). Grunow ( 1878, 125), Hustedt ( 1928, 400, 211). Heterostephania rothii Ehrenberg (1854, 35a, 14b, 4, 5). Frustules convex with depressed center; valves with fasciculate areolae forming sec· ondary rows at an angle of about 120°; small center rosette. Distribution.-Aransas, Copano, Matagorda and Galveston Bays; Pascagoula (Mis· sissippi). 91. Coscinodiscus sp. 1 (Plate 5, Fig. 91). A.S.A. (58, 44). Valves strongly convex; surface with hexagonal areolae concentric to a number of points external to the margin and intersecting; irregular central rosette present. Distribution.-Matagorda Bay. 92. Coscinodiscus sp. 2 (Plate 5, Fig. 92). Valves strongly convex, with puncta arranged in irregularly parallel rows without secondary arrangement. Distribution.-Matagorda Bay. Genus COSCINOSIRA Gran, 1900 Frustules in chains united by several filaments emanating well within the margin of the valves; cells drum-shaped, valves flat or rounded. 93. Coscinosira mediterranea Schroder (Plate 6, Fig. 93). Schroder 11911, 628, 5), Hustedt (1927, 318, 156). Frustule discoid with convex valves and without spines; cells in chains of 2-5, joined by from 2 to 5 strands; valves finely and evenly areolate. Distribution.-Upper Laguna Madre, Baffin, Corpus Christi, Aransas and Copano Bays. Genus COSMIODISCUS Greville, 1866 Cells solitary, discoid; surface punctate, puncta in radiate rows with hyaline areas between bundles of rows; central area irregular, hyaline with scattered puncta. 94. Cosmiodiscus elegans Greville (Plate 6, Fig. 94). Greville (1866, 79, 13), A.S.A. (1892, 229, 2). Actinocyclus elegans Karsten (1905, 93, 9, 9). Coscinodiscus perikompsos Rattray (1890, 576). Cosmiodiscus beaufortianus Hustedt, 1955. Frustules in girdle view undulate; valves circular, with a number of rays ending mar­ginally in small tubercles; surface punctate in fasciculate radial rows, varying in num­ber between rays; hyaline areas between fasciculae, at ends of rows of puncta and an irregular hyaline area in center. Resembles Actinocyclus except for lack of a pseudo­cellus. There is considerable variation of form in this species. Distribution.-Lower Laguna Madre; Pensacola (Florida) . Genus CYCLOTELLA Kiitzing, 1833 Frustules single or in pairs, rarely chains; discoid; valves with undulating or cen­trally raised surface; marginal areas radially striate. 95. Cyclotella comta (Ehr.) Kiitzing (Plate 6, Fig. 95). Kiitzing (1844, 20), Hustedt (1928, 354, 183). Discoplea comta Ehrenberg (1842, 267). Cells small with central swelling; striae up to half radius long radial with thickenings between every 2nd or 3rd of the striae; central area punctate in more or less radial rows. Distribution.-Upper and Lower Laguna Madre, Redfish, Aransas, Matagorda and Gal­veston Bays (dominant in the last). 96. Cyclotella kuetzingiana Thwaites (Plate 6, Fig. 96) . Thwaites (1848, 169), Hustedt (1928, 338, 171). Cells drum-shaped, tangentially swollen; valves with radial striae from margin up to half cell diameter; central area smooth with scattered puncta. Distribution.-Galveston and Aransas Bays. 97. Cyclotella menenghiniana Kiitzing (Plate 6, Fig. 97). Kiitzing (1844, 50), Boyer (1927, 28), Hustedt (1927, 341, 174). Cells in girdle view with undulate valve surfaces; valves with center area finely punc­tate; margin well defined with coarse radiating striae. Distribution.-Upper and Lower Laguna Madre, Baffin, Aransas, San Antonio, Mata­gorda, and Galveston Bays. 98. Cyclotella strwta (Klitzing) Grunow (Plate 6, Fig. 98). Grunow (1880, 119), Hustedt (1927, 344, 176). Coscinodiscus strwtus Kiitzing, 1844, 131, 1, 8. Valve surface sinuate; margin with radiate striae; central area with irregular flecks, sinuate valve surface appearing as elongated darker area. Distribution.-Upper and Lower Laguna Madre, Corpus Christi, Aransas and Mata­gorda Bays; St. Andrews Bay (Florida). 99. Cyclotella stylorum Brightwell (Plate 6, Fig. 99). Brightwell (1860, 6, 16), Hustedt (1927, 348, 179). Valves circular, large with strong tangential swelling; marginal zone broad with radial striae and marginal chambers; central area irregularly punctate with lunate or irregular puncta. Distribution.-Copano and Matagorda Bays; Pascagoula (Mississippi). Genus CYMBELLA Agardh, 1830 Frustules free, stipitate or enclosed in tubes; valve boat-shaped with a curved raphe and one valve margin more gibbous than the other. 100. Cymbella cistula (Hemprich) van Heurck (Plate 6, Fig. 100 a). van Heurck (1885, 64) , Boyer (1927, 280). Cocconema cislula Hemprich in Ehr. ( 1838, 224) ; A.S.A. ( 1875, 10, 24, 25). Valves arcuate, ventral margin swollen, ends rounded or sub-truncate, terminal nodules reflexed; central area dilated on dorsal side; distinct row of puncta on ventral side of central nodule; striae radial, punctate. Distribution.-Laguna Madre, Baffin and Corpus Christi Bays. v. maculata (Kiitzing) Grunow (Plate 6, Fig. 100 b) . Grunow (1884, 45, 1, 8). Dorsal margin lunate, ventral straight or slightly convex; raphe straight to slightly curved; striae radial at center otherwise transverse. Distribution.-St. Andrews Bay (Florida). lOL Cymbella yarrensis (A.S.) Cleve (Plate 6, Fig. 101). Cleve (1894, 162). Enc'Yonema yarrensis A.S.A. (1876, 71, 16). Cells rectangular in girdle view with rounded ends; in valve view with rounded dor· sal and straight ventral margins, slightly rostrate to capitate; raphe almost straight, slightly curved at center; axial area lanceolate, not differentiated from central area; striae transverse, radial at center. Distribution.-Upper and Lower Laguna Madre, Aransas Bay (common). A Study of the Diatom Fl,ora of Fresh Sediments of the South Texas Bays 257 Genus DIATOMA de Candolle, 1805 Frustules oblong or quadrate, in filaments attached by alternate angles; valves linear to elliptic with transverse costae, rows of puncta and a pseudoraphe. 102. Diatoma hiemale (Lyngbye) Heiberg (Plate 6, Fig. 102). Heiberg (1853, 68), Hustedt (1931, 102, 631). Fragilaria hiemale Lyngbye ( 1819, 185). Cells in girdle view rectangular with rounded ends; girdle bands numerous valves linear to linear-lanceolate, varying in shape; ends rounded, may be produced; transapi­cal ribs coarse, often irregular with striae between; pseudoraphe linear, crossed by ribs. Distribution.-Lower Laguna Madre, Aransas, Matagorda, and Galveston Bays; Carra­belle (Florida). Genus DIMEROGRAMMA Ralfs 1861 Frustules quadrangular raised and hyaline at the corner<:; chains formed; va\ves elliptic-lanceolate to linear; pseudoraphe lanceolate; hyaline areas at ends but not in the middle. 103. Dimerogramma marinum Ralfs (Plate 6, Fig. 103 a, b). Ralfs (1861, 790), Boyer (1916, 46, 12, 9-10; 1927, 193). Valves lanceolate, ends produced; hyaline areas at ends small; pseudoraphe lanceo­late; striae consisting of 4 to 5 rows of coarse puncta perpendicular to margin. Distribution.-Aransas Bay. 104. Dimerogramma minor (Gregory) Ralfs (Plate 6, Fig. 104 a-d). Ralfs (1861, 790), Hustedt (1931, 118, 640, 641). Denticula minor Gregory ( 1857, 23, 2, 35). Frustules in chains or single, in girdle view with undulate valves, ends obliquely produced, valves touching at ends and in the middle; valves bicuneate, apical areas round, hyaline; pseudoraphe linear, may be widened towards middle of valve. Distribution.-Lower Laguna Madre, Aransas, Copano and Matagorda Bays. Genus DIPLONEIS Ehrenberg, 1840 Valves elliptical to panduriform; raphe enclosed in strong siliceous horns; resembling the lateral areas of Navicula lyra but never punctate, central nodule quadrate. 105. Diploneis bombus Ehr. (Plate 6, Fig. 105). Ehrenberg ( 1844, 84) , Hustedt ( 193 7, 7 04, 1086) . Valves panduriform; central area large, quadrate horns more or less divergent at base, then convergent; longitudinal canal linear; transapical ribs strong, radial, crossed by 2-5 longitudinal ribs parallel to margins. Distribution.-Upper and Lower Laguna Madre, Corpus Christi, Aransas, Copano, San Antonio, Matagorda and Galveston Bays. 106. Diploneis chersonensis (Grunow) Cleve, 1894 (Plate 6, Fig.106). Cleve (1894, 91), Hustedt (1937, 709, 1088). Navicula chersonensis A.S.A. (1875, 12, 40). Valves panduriform, ends rounded to subacute; central nodule moderate; horns nar­ row, parallel with a row of large puncta; costae strongly marked, radiate crossed by 2 or more usually straight, rarely irregular longitudinal ribs. Distribution.-Aransas, Copano, and Matagorda Bays. 107. Diploneis cynthia (A.S.) Cleve (Plate 6, Fig. 107). Cleve (1894, 82), Hustedt (1937, 599, 106). N avicula cynthia A.S.A. ( 1875, 8, 41). Valves elliptic to rhombic-elliptic; central area rather small, quadrate; horns parallel; longitudinal canals broad; ribs tranverse to radial; loculi unpaired. Distribution.-Aransas, Copano and Matagorda Bays. 108. Diploneis fusca (Gregory) Cleve (Plate 6, Fig. 108). Cleve (1894, 93) , Hustedt (1937, 654, 1053). Navicula smithii var. fusca Gregory (1857, 14, 1, 15). Valves elliptic to linear-elliptic; central nodule large, subquadrate; horns strongly marked, tapering towards apices, expanded near central area; costae transverse strong, radial to parallel with numerous longitudinal ribs; areolae adjacent to horns in group~ of 4 to 5. Most specimens in this region are asymmetric. Distribution.-Corpus Christi, Aransas, Matagorda and Galveston Bays. 109. Diploneis gemmatula (Grunow) Cleve (Plate 6, Fig. 109). Cleve (1894, 103) , Hustedt (1937, 626, 1038). Navicula gemmatula Grunow in A.S.A. (1875, 13, 20). Valves linear, sides constricted, ends obliquely rounded; central area small, rounded· quadrate; horns strong, parallel, converging at ends; longitudinal canal broad, linear; striae transverse to radial, loculi with rounded to elliptical pores forming longitudinal lines. Distribution.-Redfish Bay. 110. Diploneis ovalis (Hilse) Cleve (Plate 6, Fig. 110). Cleve (1891, 44, 2, 13) , Hustedt (1937, 671, 1065). Pinnularia ovalis Hilse in Rabenhorst 1861, 1025. Navicula ovalis A.S.A. (1875, 7, 33-36). Valves broadly· to linear-elliptic with convex sides and broadly rounded ends; central area large, variable; horns strong, parallel; longitudinal canal usually' narrow; ribs transverse, strong, crossed by somewhat irregular longitudinal lines. Distribution.-Aramas Bay, Copano Bay. 111. Diploneis papula (A.S.) Cleve (Plate 6, Fig. 111). Cleve (1894, 85), Hustedt (1937, 679, 107la-c). NaviculapapulaA.S.A. (1875, 7,45--47; 69,33). Valves elliptic to linear-elliptic with slightly convex to parallel sides and broadly rounded ends; central nodule small, quadrate; horns strong, divergent at base, con· vergent at ends; longitudinal canal narrow, lanceolate; striae transverse, slightly radial, crossed by a longitudinal, sub-marginal line. Distribution.-Aransas and Redfish Bays. A Study of the Diatom Fl.ora of Fresh Sediments of the South Texas Bays 259 112. Diploneis smithii (Brebisson) Cleve (Plate 6, Fig. 112). Cleve (1894, 96), Hustedt (1937, 647, 1051). Navicula smithii Breb. in W. Smith (1856, 92). Valves elliptic; central nodule more or less elliptic, ends truncate; horns parallel on inner, evenly curved on outer edge; costae transverse, radial towards end, separated by 2 rows of areolae, decreasing in size from margin. Distribution.-Upper Laguna Madre, Aransas, Copano, Matagorda and Galveston Bays. 113. Dipfoneis splendida (Gregory) Cleve (Plate 6, Fig. 113). Cleve (1894, 87), Hustedt (1937, 712, 1089). Navicula splendida Gregory, 1856, 44, 5, 14. Valves panduriform; central area moderate, quadrate to rounded; horns strong, paral­lel; longitudinal canal broad, linear, slightly constricted at ends; ribs radial, crossed by straight to irregular longitudinal lines farther apart than the transverse ones; a row of pores on the longitudinal canal. Distribution.-Aransas Bay. 114. Diploneis weissflogii (A.S.) Cleve (Plate 6, Fig. 114). Cleve (1894, 91), Hustedt (1933, 703, 1085). Navicula weissflogii A.S.A., 1875, 12, 26-32. Valves constricted in the middle; evenly rounded with round ends; central area small; horns almost parallel, approaching slightly at ends; transapical costae coarse, elongated in the middle, somewhat radial, crossed by several almost straight or slightly irregular longitudinal lines, broken on either side of the central nodule. Distribution.-Aransas, Copano, San Antonio, Matagorda and Galveston Bays. Genus ENDICTYA Ehrenberg, 1845 Frustules in chains; cylindric; surface areolate; margin with strong teeth. 115. Endictya oceanica Ehr. (Plate 6, Fig. 115) . Ehrenberg (1845, 76), Hustedt (1928, 297, 136). Cells cylindric; valves flat; areolae coarse, slightly diminishing towards margin; corners of areolae papillate; inner mesh finely punctate; margin with fine teeth; mantle areolate. Distribution.-Matagorda Bay. Genus EPITHEMIA Brebisson, 1838 Cells epiphytic; rectangular in girdle view, sometimes swollen in the middle; valves arcuate with an inner costate and outer punctate strata. It seems logical to unite the genera Epithemia and Rhopal.odia as the distinction is slight and species of both genera are very variable, but to avoid confusion the customary separation will be followed here. 116. Epithemia argus (Ehr.) Kiitz. (Plate 6, Fig.116). Kiitzing (1844, 35, 29, 55, 56). Eunotia argus Ehrenberg (1842, 125). Valves with arcuate dorsal and almost straight ventral margin, ends rounded; costae strong, alternating with more than 2 rows of puncta. Distribution.-Redfish, Aransas, and Galveston (rare) Bays. 117. Epithemia zebra (Ehr.) Kiitz. (Plate 6, Fig. 117). Kiitzing ( 1844, 34, 12, 3-5), Boyer ( 1927, 490). Navicula zebra Ehrenberg (1833, 262). Valves with arcuate dorsal and straight ventral margins; ends acute to produced; costae radiate with several rows of puncta between. Distribution.-Corpus Christi, Aransas and Copano Bays. Genus EUNOTIA Ehrenberg, 1837 Frustules epiphytic, in bundles or single; valves arcuate with transverse striae; raphe rudimentary at terminal nodules, no central nodule. 118. Eunotia hebrUlica A. Berg (Plate 6, Fig. 118). A. Berg in Cleve Euler (1953, 121, 459). Valves linear, more or less elongate, slightly curved with parallel sides and capitate ends; terminal nodules large, striae coarse transverse. Distribution.-Pensacola Bay (Florida). Genus EUNOTOGRAMMA Weisse, 1854 Frustules rectangular; valves elliptic to lunate, divided by septa which constrict the margin. 119. Eunotogramma laeve Grunow (Plate 7, Fig. 119). Grunow in van Heurck ( 1880-1885, 126, 6, 7, 9, 15). Frustules rectangular; valves with 2 to 6 pseudosepta, which number may differ on 2 valves of the same cell; one margin straight, the other arcuate. Distribution.-Matagorda Bay'. 120. Eunotogramma marinum (W. Smith) Peragallo (Plate 7, Fig. 120 a,b). Himantidium marinum W. Smith (1857, 10, 2, 14), Hustedt (1955, 10, 4, 10-17). Frustules rectangular; valves linear to linear.lanceolate with 4 to 18 pseudosepta, one margin straight, the other slightly arcuate. Distribution.-Matagorda and upper Galveston Bays; Houston. Genus EUPODISCUS Ehrenberg, 1844 Valves circular, areolate with 2 to 4 ocelli but no ridges or processes. 121. Eupodiscus ovalis (A.S.) (Plate 7, Fig. 121). (non Norman, 1861) A.S.A. (U5, 5--7; 1940, 440, 8, 9) . Biddulphia ovalis Boyer (1901, 712). Valves flat, circular, with fine radiate areolae; ocelli large. Hustedt ( 1940 I.e.) con­ siders this species close to Eupodiscus and in fact it fits this genus better than Cerataulus, Distribution.-Upper Laguna Madre. 122. Eupodiscus radiatus Bailey (Plate 7, Fig. 122). Bailey (1851, 39), A.S.A. (1940, 440, 3-5). Valves circular, flat, slightly rounded at margins where there are 4 irregularly spaced ocelli; valve surface with indefinitely arranged, coarse, hexagonal areolae, and a punctate stratum. Distrihution.-Matagorda Bay. Genus FRAGILARIA Lyngbye, 1819 Frustules in ribbons, more or less rectangular; valves lanceolate to cruciform; pseu· doraphe variable; striae transverse. 123. Fragilaria brevistriata Grunow (Plate 7, Fig. 123). Grunow ( 1881, 45, 32, 34) . Cells forming ribbons; valws linear to linear-lanceolate, with bluntly rounded to pro· duced ends; striae short, marginal; pseudoraphe lanceolate, broad. Distribution.-Matagorda and Aransas Bays. 124. Fragilaria capucina Desm. (Plate 7, Fig. 124). Desm. (1825, Plants Crypt. France, 453) , Boyer (1927, 187), Hustedt (1931, 144, 659 a-h). Frustules in long ribbons, linear with blunt ends in girdle view; valves linear with sub· rostrate apices; striae transverse, marginal. Distribution.-Laguna Madre, Baffin Bay, Aransas Bay. 125. Fragilaria construens {Ehr.) Grunow {Plate 7, Fig. 125). Grunow ( 1862, 371, 7, 10), Hustedt (1931, 156, 670a,c). Staurosira construens Ehrenberg, 1841, 424. Cells in girdle view rectangular, often very long; valves of very varied shape, lanceo­late to cruciform or triangular; striae coarse; pseudoraphe lanceolate. Distribution.-Baffin Bay. 126. Fragilaria pinnata Ehr. (Plate 7, Fig. 126). Ehrenberg (1841, (1843). 127, 1, 3, 9), Hustedt in A.S.A. (1913, 297, 55--58, 65-72; 298, 47-74). Valves lanceolate to elliptic-lanceolate with rounded ends, very variable in shape; costae broad, slightly alternate. Distribution.-Upper Laguna Madre, Corpus Christi Bay, Aransas Bay, Matagorda Bay; Florida coast. 127. Fragilaria virescens Ralfs (Plate 7, Fig. 127). Ralfs (1843, 12, 110), A.S.A. tl913, 297, 3-33), Boyer (1927, 184) . Frustules rectangular, in long ribbons; valves linear to linear-elliptic attenuate at apices, obtuse; transversely striate, punctate; pseudoraphe jndistinct, variable. Distribution.-Lower Laguna Madre. Genus FRUSTULIA Agardh, 1824 em. Grunow, 1865 Valves naviculoid; raphe between two thickened, hyaline ribs; central and terminal nodules frequently elongate; valve surface with longitudinal and transverse lines. 128. Frustulia interposita (Lewis) de Toni (Plate 7, Fig. 128 a,b). de Toni (1891, 278), Hustedt (in A.S.A. 1930, 369, 10). 262 A Study of the Diatom Flora of Fresh Sediments of the South Texas Bays Navicula interposita Lewis (1865, 2, 19). Valves linear-elliptic with broadly rounded ends; axial ribs strong; central pores of raphe distant; central area symmetrical (differing from that shown by Hustedt (I.e.) ; longitudinal and transverse network of valve surface regular except near central area. Distribution.-Aransas Bay. 129. Frustulia rhomboUles (Ehrenberg} de Toni (Plate 7, Fig. 129a). de Toni (1891, 277), Hustedt (1937, 728, 1098). Navicu/,a rhomboides Ehrenberg ( 1841, 3, 15). Valves rhombic to lanceolate with rounded ends; raphe with central nodules distant, axial ribs strong; longitudinal and transverse network of valve surface regular except for central area. Distribution.-Aransas Bay. v. saxonica (Rabenhorst} de Toni (Plate 7, Fig. 129 b). de Toni (1891, 277), Hustedt (1937, 729, 1099). Valves elliptic-lanceolate, ends more or less produced. Distribution.-Laguna Madre. Genus GRAMMATOPHORA Ehrenberg, 1840 Frustules rectangular; forming zig-zag chains; valves lanceolate with gibbous center; septa two, usually slightly sigmoid. 130. Grammatophora maxima Grunow (Plate 7, Fig. 130). Grunow (1862, 416, 8, 5) , Hustedt (1933, 44, 572). Frustules with coarse septa, rather coarser than in G. marina; valve surface finely areolate; valves linear, slightly gibbous, pseudoraphe narrow. Distribution.-Lower Laguna Madre. 131. Grammatophora marina (Lyngbye) Kiitzing (Plate 7, Fig. 131 a,b). Kiitzing (1884, 17, 24) , Boyer (1927, 56.) Diatoma marinum Lyngbye (1819, 180, 62). Cells in zig-zag chains or single; frustules in girdle view rectangular, with rounded ends, in valve view linear or linear-elliptic; internal sep•a straight or curved near margin with knobbed ends; valve surface areolate. Distribution.-Laguna Madre, Corpus Christi, Aransas and San Antonio Bays. 132. Crammatophora oceanica Ehr. (Plate 7, Fig. 133) . Ehrenberg (1854), Hustedt (1931, 45, 573-4). Cells solitary or in zig-zag chains; frustules in girdle view linear-oblong; septa appear H-shaped near margin, linear with knobbed ends; values lanceolate, ends may be slightly capitate; striae very faint. Distribution.-Laguna Madre, Corpus Christi and Aransas Bays. Genus HANTZSCHIA Grunow, 1877 Valves bean-shaped with rostrate ends; keel puncta short, raphe lateral on keel; surface of valve striate. 133. Hantzschia amphioxys (Ehr.) Grunow. Grunow ( 1880, 103), A.S.A. ( 1930, 329, 11, 12, 15, 20). Eunotia amphioxys Ehrenberg, 1841, 25, 1, 26. Valves slightly arcuate with capitate apices; keel puncta irregular; striae transverse. v. compacta Hustedt (Plate 7, Fig. 133). Hustedt in A.S.A. (1930, 345, 11). Frustule broader than type, valve more sinuate; striae transverse. Distribution.-Florida Gulf coast. 134. Hantzschia marina (Donkin) Grunow (Plate 7, Fig. 134) . Grunow (in Cleve & Grunow, 1880, 105), Boyer (1916, 114, 32, 22). Epithemia marina Donkin ( 1858, 29, 3, 14) . Valve bean-shaped, capitate, with dorsal margin slightly arcuate, ventral straight; keel puncta prolonged into striae across valve; separated by puncta. Distribution.-Upper Laguna Madre, Aransas Bay. Genus HUTTON/A Grove & Sturt, 1887 Frustules rectangular; valves twisted on pervalvar axis; ocelli on blunt processes within valve margin. 135. Huttonia reichardtii Grunow (Plate 7, Fig. 135). Grunow (1888, 39), Hustedt (1929) . Cells equidimensional in girdle view with sinuate girdle and processes set at an angle, within valve corners; valves circular but irregularly depressed near ocelli; valve and girdle surface areolate. Distribution.-Copano and Matagorda Bays. Genus LICMOPHORA Agardh, 1827 Frustules cuneate, stipitate, often forming more or less branched, fan-shaped colonies; septate; valves cuneate with rounded or capitate distal ends, proximal end acute. 136. Licmophora fiabellata (Carmichael) Agardh (Plate 7, Fig. 136). Agardh (1830-1832, 41), Boyer (1927, 165), Hendey (1951, 39, 16, 1, 2, 12). Cells frequently attached basally to a branched stipe, up to 20 cells per stipe; frustule in girdle view cuneate, with numerous septa penetrating from upper part of cell; valves cuneate-lanceolate to clavate; base slightly swollen; faintly striate. Distribution.-Aransas Bay, rare in muds. Genus LITHODESMIUM Ehrenberg, 1840 Frustules prismatic, chain forming; attached by persistent girdle bands and a central spine; valves triangular, undulate with raised center and 3 marginal processes. 137. Lithodesmium undulatum Ehr. (Plate 7, Fig. 137). Ehrenberg (1840, 75, 4, 13), Hustedt (1930, 789, 461). Frustules prismatic, in chains; valves with central spine, undulate with 3 raised termi­nal processes; surface with radial puncta. Distribution.-Copano Bay, Matagorda Bay (normally a planktonic species). 264 A Study of the Dwtom Flora of Fresh Sediments of the South Texas Bays Genus MASTOGLOIA Thwaites, 1856 Frustules rectangular; valves naviculoid; surface with transverse and diagonal or longitudinal lines; a loculiferous plate between valve and girdle. 138. Mastogloia acutiuscula Grunow (Plate 7, Fig. 138 a,b). Grunow (1883, 495), Hustedt (1931-1933, 515, 947). Valves linear·lanceolate with acutely rounded ends; raphe straight, between 2 coarse, longitudinal ribs; surface with transverse ribs; loculi even, numerous, not reaching ends. Distribution.-Upper Laguna Madre. 139. Mastogloia angulata Lewis (Plate 7, Fig. 139). Lewis (1861, 65), Boyer (1927, 334), Hustedt (1931-1933, 465, 885). Valves elliptic with slightly produced ends; loculi numerous, two or three larger loculi in the middle; axial area narrow; central area small, may be almost absent; striae punctate in rows parallel to transverse axis. Distribution.-Upper Laguna Madre, Aransas Bay. 140. Mastogloia apiculata W. Smith (Plate 7, Fig. 140, a,b). W. Smith (1856, 65) , Hustedt (1931-1933, 515, 946). Valves elliptic-lanceolate, sometimes produced; raphe straight, enclosed between 2 longitudinal ribs; central area very small; striae transverse to slightly radiate, punctate; puncta in logitudinal rows; loculi small, even, almost reaching ends of valves. Distribution.-Upper and Lower Laguna Madre, Corpus Christi, Aransas and Galveston Bays; St. Andrews Bay (Florida). 141. Mastogloia asperula? Grunow (Plate 7, Fig. 141). Grunow ( 1892, 23, 12), Hustedt ( 1933, 480, 901). Valves elliptic-lanceolate with rostrate ends; raphe straight to sinuate; axial area very narrow; central area small, round; surface areolate, forming a network of crossing sys­tems; areolae hexagonal; loculi small, even, reaching apex. Distribution.-Aransas Bay. 142. Mastogloia baldjikiana Grunow (Plate 7, Fig. 142). Grunow (in A.S.A., 1893, 188, 1, 2), Hustedt (1931-1933, 550, 981). Valves rounded, elliptic or elongate with rounded to subrostrate ends; raphe straight or ·excavated; axial area very narrow; central area widened to form two longitudinal furrows; valve surface with transverse costae crossed by faint longitudinal ridges; loculi even, about 10, not reaching ends. Distribution.-Upper and Lower Laguna Madre, Aransas and Copano Bays, Florida Gulf Coast. 143. Mastogloiabinotata (Grunow) Cleve (Plate7,Fig.143). Cleve (1895, 148), Hustedt (1931-1933, 470, 889). Orthoneis binotata Grunow, 1867, 15. Valves broadly elliptic with evenly rounded ends; raphe straight; axial area very narrow; central area transverse, sagittate; valve surface areolate, areolae forming an even network; one long loculus on either side, with inner margin straight. Distribution.-Lower Laguna Madre. 144. Mastogloia braunii Grunow (Plate 8, Fig. 144). Grunow (1863, 156, 4, 2), Hustedt (1931-1933, 551, 982). Valves lanceolate with tapering or slightly produced ends; raphe strong I y curved; axial area narrow, central area large, rectangular, extending into H-shaped extensions towards apices; loculi rectangular, numerous, some enlarged; not reaching ends ; puncta in transverse rows; longitudinal rows narrower than transverse. Distribution.-Upper Laguna Madre. 145. Mastogloia chersonensis A.S. (Plate 8, Fig.145 a,b). A.S.A. (1893, 186, 31, 32), Hustedt (1931-1933, 565, 999) . Valves linear-elliptic to linear-lanceolate, almost rhombic, with broadly rounded ends; raphe sinuate, axial area narrow; surface with transverse, slightly radial striae, longi­tudinal interrupted lines; loculi small, numerous, narrowest in the middle. Distribution.-Redfish Bay. 146. Mastogloia cocconeiformis Grunow (Plate 8, Fig. 146) . Grunow (1860, 578, 7, 13) , Hustedt (1931-1933, 469, 888). Valves elliptic, almost circular; raphe slightly curved; axial area very narrow; central area small, circular to elliptic; valves with even, hexagonal areolae forming a threefold system; loculi narrow, numerous, reaching apices. Distribution.-Aransas Bay. 147. Mastogloia cribrosaGrunow (Plate 8, Fig. 147). Gurnow (1860, 577, 5, lOc) , Hustedt (1931-1933, 468, 887). Cells solitary', often enclosed in a gelatinous sheath; valves broadly elliptic; central nodule small, raphe straight; areolae transverse, regular; loculi numerous, reaching apex. Distribution.-Upper and Lower Laguna Madre, Aransas Bay. 148. Mastogloia crucicula (Grunow) Cleve (Plate 8, Fig. 148 a,b). Cleve (1895, 148), Hustedt !1955, 19, 6, 12). Orthoneis crucicula Grunow ( 1877, 177, 195, 8). Valves elliptic, ends rounded to acute; raphe straight; axial area narrow, straight; central area transverse, forming a stauros; areolae in radiate rows, loculi 4 on each side, elongate. Distribution.-Aransas Bay. 149. Mastogloia erythraea Grunow (Plate 8, Fig. 149). Grunow ( 1860, 577, 7, 4). Mastogloia interrupta Hantzsch in Rabenhorst (1863, 20, 6a, 5a,b), A.S.A. ( 196, 37). Valves lanceolate to rhombic lanceolate with more or less produced acute ends; raphe sinuate, areas narrow; surface transversely striate, longitudinal lines present; loculi small in the middle and at the ends, larger between. Distribution.-Aransas Bay. 150. Mastogloia horvathiana Grunow (Plate 8, Fig. 150). Grunow (1860,578, 7,13),A.S.A. (188,41),Hustedt (1931-33,471,890). Valves broadly elliptic; raphe curved; axial area very narrow; central area small; valve sudace evenly areolate, forming radiate and concentric systems; loculi numerous, narrow, reaching apices. Distribution.-Upper Laguna Madre. 151. Mastogloia labuensis Cleve (Plate 8, Fig.151). Cleve in A.S.A. (1893, 187, 2), Hustedt (1931-33, 578, 950). Valves linear, sides parallel, ends acute, slightly produced; raphe straight; axial area straight, central area elliptic; striae transverse with irregular longitudinal lines; loculi numerous, even, not reaching apex. Distribution.-Upper Laguna Madre. 152. Mastogloia lanceolata Thwaites (Plate 8, Fig. 152 a,b). Thwaites in W. Smith (1856, 64, 54, 340), Hustedt (1931-33, 497, 922). Valves lanceolate with bluntly rounded or slightly produced ends; raphe slightly curved in the middle; axial area very narrow, central area small, circular; valve surface with transverse and irregular longitudinal striae; loculi numerous, not reaching apices. Distribution.-Aransas Bay, dominant at one station in Lower Laguna Madre. 153. Mastogloia latericia (A.S.) Cleve (Plate 8, Fig. 153). Cleve (1895, 162). Orthoneis latericia A.S.A. (1893, 188, 40). Valves elliptic with acute ends; raphe straight, axial and central areas narrow; areolae in transverse rows forming irregular longitudinal pattern; loculi rectangular, not reach· mg apex. Distribution.-Aransas Bay. 154. Mastogloia pumila (Grunow) Cleve (Plate 8, Fig. 154 a,b,c). Cleve (1895, 157), Hustedt (1931-33, 553, 983). M. braunii v. pumila Grunow, in van Heurck (1880-85, 4, 23). Valves linear-lanceolate with tapering, rounded ends; raphe straight; axial area nar· row; central area rectangular, extended apically to form an H-shaped lateral area; strong radial ribs on transverse axis, longitudinal lines fine; loculi 6 to 8, one to three in the middle larger, not reaching ends. Distribution.-Upper Laguna Madre; Fort Pike (Mississippi). 155. Mastogloia pusilla Grunow (Plate 8, Fig. 155). Grunow ( 1878, 111, 3, 11), Hustedt ( 1931-33, 568, 1002a-c). Valves linear-elliptic with lanceolate to rounded or slightly produced ends; raphe straight, areas very narrow; striae transverse, crossed by" slightly closer longitudinal striae; central loculi larger, loculi not reaching ends. Distribution.-Upper Laguna Madre, Corpus Christi and Aransas Bays; St. Joe's (Florida). 156. Mastogloia quinquecostata Grunow (Plate 8, Fig. 156). Grunow (1860, 578, 7, 8), Hustedt (1931-33, 556, 989). Valves linear·elliptic with acute ends; raphe undulate; axial area narrow; loculi 18-20 almost reaching apices; valve surface with punctate, transverse striae, with irregular longitudinal arrangements; on each side of raphe are several longitudinal depressions which lack striae. Distribution.-Lower Laguna Madre. 157. Mastogloia smithii Thwaites (Plate 8, Fig. 157). Thwaites (in W. Smith, 1856, 65, 54, 341), Boyer (1916, 87, 17, 19) , Hustedt (1931-33, 502, 928a). Frustules in valve view elliptic-lanceolate, ends slightly produced; raphe straight; axial area narrow, central area small, round; striae transverse, punctate, forming longitudinal lines; loculi usually 6-9, not reaching apices. Distribution.-Upper Laguna Madre, Aransas Bay. 158. Mastogloia subafjirmata Hustedt (Plate 8, Fig. 158 a, b). Hustedt in A.S.A. (1927, 368, 13; 1931-1933, 526, 960a-f). Valves broadly elliptic to rhombic lanceolate with produced, sharp ends; raphe strongly curved, narrow; areas narrow, following raphe; surface with transapical striae crossed by irregular longitudinal lines; loculi numerous, small. Distribution.-Lower Laguna Madre. Genus MELOS/RA Agardh, 1824 em. de Toni, 1892 Frustules cylindrical to globose, attached by valve ends to form straight chains; furrow between valve and girdle usually evident. 159. Melosira granulata (Ehrenberg) Ralfs (Plate 8, Fig. 159). Ralfs (in Pritchard, 1861) , Hustedt (1927, 248, 104). Callionella granulata Ehrenberg ( 1843, 170) . Frustules in chains, may be slender, elongate, broad or short, with wide, clear apertures between alternate cells; puncta more or less spiral, may be large or small; a variable form. Distribution.-Corpus Christi, Redfish and Galveston Bays; Pascagoula (Mississippi). 160. Melosira nummuloides (Dillwyn) Agardh (Plate 8, Fig. 160). Agardh (1824, 8), Hustedt (1927, 231). Conferva nummuloUles Dillwyn (1809, 43). Frustules spherical to cylindric:elliptic with flattened apices and cylindrical mantle; valve surface punctate with radial margin. Distribution.-Upper Laguna Madre, Corpus Christi, Aransas and Matagorda Bays. 161.· M elosira ornata Grunow (Plate 8, Fig. 161). Grunow (1884, 9S, 39, 40), Hustedt (1927, 274, 117). Frustules in cylindrical chains with low mantle; valves flat, walls strong with a fine, threefold pore arrangement and a series of inwardly open chambers around the margin, internally concentric markings and irregularly arranged puncta. Distribution.-Aransas Bay. 162. Melosira setosa Greville (Plate 8, Fig. 162). Greville (1866, 436, 6, 17-19), A.S.A. (182, 42-46). Frustules in short chains, subspherical; valves with rounded margins, evenly areolate with a mat of setae on somewhat flattened valves. Distribution.-Upper Laguna Madre, Baffin Bay, Matagorda Bay. 163. Melosira sulcata (Ehr.) Kiitzing (Plate 8, Fig. 163). Kiitzing (1844, SS, 2, 7), Hustedt (1927, 276, 119). Frustules usually in short chains or single, thick walled, discoid with robust margin and coarsely granulate surface in girdle view; valves with strongly reinforced margin and rays extending a variable distance towards center which is usually hyaline. Distribution.-Upper Laguna Madre, Baffin, Aransas, San Antonio, Espiritu Santo, Matagorda and Galveston Bays. Genus NAVICULA Bory, 1826 Valves linear to elliptic, ends variable, raphe straight, axial area usually distinct; cen· tral area may be small or extended into lyrate lateral areas; striae transverse to radiate, punctate. 164. Navicula ambigua Ehr. (Plate 8, Fig. 164). Ehrenberg (1842, 2, 9), A.S.A. (211, 42-47). Valves elliptic-lanceolate with capitate ends; axial and central areas narrow; striae transverse; frustule craticulate. Distribution.-Aransas, San Antonio, and Galveston Bays; Pensacola Bay (Florida). 165. Navicula clavata Gregory (Plate 9, Fig.165). Gregory (18S6-7, 46, S, 17), A.S.A. (1876, 70, SO) , Boyer (1927, 415). Valves elliptic; lateral areas semi-lanceolate, ends diverging, interrupting the trans­ verse punctate striae. Distribution.-Aransas and Matagorda Bays. 166. Navicula delawarensis Grunow (Plate 9, Fig. 166). Grunow (1891, 13, 1, 8, 7), Boyer (1916, 92, 25, 3; 1927, 406) , A.S.A. (244, 10, 11). Valves elliptic with produced apices; axial area narrow, central area slightly bilobed; striae fairly coarse, radiate, punctate. Distribution.-Aransas Bay. A Study of the Diatom Flnra of Fresh Sediments of the South Texas Bays 269 167. Navicu"/a directa (W. Smith) Ralfs (Plate 9, Fig. 167). Ralfs (1861, 906), A.S.A. (1875, 47, 1-5), Boyer (1927, 395) . Valves elongate-lanceolate, ends acute; axial and central areas narrow, even; striae coarse transverse, parallel. Distribution.-Laguna Madre, Baffin, Aransas and Matagorda Bays. 168. Navicula distans (W. Smith) Ralfs (Plate 9, Fig. 168). Ralfs (1861, 907), A.S.A. (1878, 46, 11-14). Pinnularia distans W. Smith, 1853, 56, 18, 169. Valves linear-lanceolate with acutely rounded ends; raphe curved; axial area narrow, even; central area wide, oblong, bounded by 2 or 3 very short striae; striae coarse, punc­tate, radiate. Distribution.-Baffin, Matagorda and Aransas Bays. 169. Navicu"/a diversistriata Hustedt (Plate 9, Fig. 169 a,b). Hustedt ( 1955, 28, 9, 6-9) . Valves elliptic-lanceolate with acute, subrostrate ends; axial area narrow-lanceolate somewhat dilated between apical and terminal nodules; structure of 2 valves different in one the central area is dilated, in the other not; striae radiate in the former, transverse in the latter. Distribution.-Baffin, Galveston and Aransas Bays. 170. Navicula forcipata Greville (Plate 9, Fig.170). Greville (1859, 83, 6, 10-11), A.S.A. ( 1876, 70, 18). Valves elliptic to linear-elliptic; surface striate, punctate; striae transverse, inter­rupted by hyaline lateral areas constricted in the middle and at the ends; axial area dilated at central nodules. Distribution.-Upper Laguna Madre, Corpus Christi, Aransas and Matagorda Bays. 171. N avicula granulata Bailey (Plate 9, Fig. 171) . Bailey (1853, 7, 10), Boyer (1927, 404). Valves elliptic-lanceolate, broad; axial area may be straight or lanceolate; central area round; striae at right angles to margin, punctate, often irregular towards center. Hustedt (1955) rightly unites N. brasiliensis with N. granulata; both forms and inter­grades are common in the Texas material. Distribution.-Laguna Madre, Aransas, San Antonio and Matagorda Bays; Pensacola Bay (Florida). 172. Navicula grevillei Agardh (Plate 9, Fig. 172). Agardh (1830, 18), Cleve (1894, 152) . Valves elliptic-lanceolate with obtuse ends: axial area indistinct; central area small; striae closer at the ends, the 4-5 median striae being more radiate than the others. Frustules often encased in a mucilaginous tube (Schizonema). Distribution.-Laguna Madre. 173. Navicula hummii Hustedt (Plate 9, Fig. 173). Hustedt (1955, 23, 8, 8-10, 24). Valves broadly elliptic; raphe straight with terminal nodules distant from the ends, central pores distant; axial area wide, contracted at middle and at ends; central area forming a stauros and bow-shaped lateral areas separated from the axial area by a row of coarse puncta; striae punctate at right angles to lateral area. Distribution.-Lower Laguna Madre, Aransas Bay. 174. Navicula impressa Grunow (Plate 9, Fig. 174). Grunow in A.S.A. (1875, 6, 17, 18, 36), Boyer (1927, 407). Valves broadly lanceolate, sides parallel, slightly constricted in the middle, ends acute rostrate; axial area narrow; central area slightly dilated; striae transverse, central ones may be interrupted; punctate. Distribution.-Upper Laguna Madre. 175. Navicula longa Gregory (Plate 9, Fig. 175). Gregory (1856, 47, 5, 18), Ralfs (1861, 906), Boyer (1916, 27, 20; 1927, 297). Valves linear-lanceolate, elongate; axial and central areas small; striae coarse, radiate. Distribution.-Corpus Christi Bay. 176. N avicula nummularia Greville (Plate 9, Fig. 176). Greville (1859, 249, 5, 6), Hustedt (1955, 22, 7, 15, 16). Valves elliptical to circular; raphe straight, axial area narrow, central area extended, the lateral areas forming an 8; striae coarse, radiate with puncta between. Distribution.-Lower Laguna Madre. 177. Navicula peregrina (Ehr.) Klitzing (Plate 9, Fig. 177). Klitzing (1844, 97, 28, 52), Boyer (1916, 94, 26, 20; 1927, 339). Pinnularia peregrina Ehrenberg ( 1844, 133) . Frustules in valve view linear-lanceolate with abruptly rounded ends; central area oval or rectangular, larger on one side; striae radiating at center, otherwise at right angles to margin. Distribution.-Aransas Bay. 178. Navicula pseudobacillum Grunow (Plate 9, Fig. 178). Grunow ( 1880, 45, 2, 52), Cleve ( 1894, 137). Valves linear-elliptic with rounded ends; terminal nodules expanded laterally; axial area narrow, raphe broad; central area small; striae more distant in the middle than at the ends, radial, finely punctate. Distribution.-Carrabelle (Florida) . 179. Navicula punctigera Hustedt (Plate 9, Fig. 179). Hustedt (1955, 26, 7, 4). Valves broadly elliptic, rap he straight; axial area lanceolate, rather large; central area irregular, somewhat transapically dilated; striae radiate, distinctly punctate, some shorter striae in middle of valve. Distribution.-Matagorda Bay. 180. Navicula rostellata Kiitzing (Plate 9, Fig. 180). Kiitzing (1844,95,3,65),A.S.A. (1876,47,31). Valves elliptic-lanceolate with rostrate ends; axial and central areas narrow; striae coarse, radiating at center, transverse at ends. Distribution.-Aransas Bay. 181. Navicula ruttneri Hustedt (Plate 9, Fig. 181). Hustedt in A.S.A. (1936, 402, 30-52) . Valves lanceolate with broadly rounded ends, sometimes produced to capitate; raphe straight; central nodules prominent; axial area narrow-lanceolate; striae coarse with cen· tral area dilated; one or two short striae irregularly spaced in central region. Distribution.-Aransas Bay, Carrabelle (Florida) . 182. Navicula seductilis A.S. (Plate 9, Fig. 182). A.S.A. ( 1875, 2, 35) . N. lyra v. seductilis Cleve (1895, 64). Valves linear-elliptic, ends rounded, acute; raphe straight; axial area narrow; central area extended longitudinally forming an H about half cell width, tapering to apices; striae relatively coarse, punctate. The lateral areas are not lyrate as in N. lyra and there seems no reason for following Cleve in retaining this among the too numerous N. lyra forms. Distribution.-Aransas Bay. 183. Navicula spuria Cleve (Plate 9, Fig. 183). Cleve ( 1895, 31) , Peragallo ( 1908, 12, 5) . Valves narrow-lanceolate, acute ; axial area very narrow; central area small, striae radiate in the middle, parallel at ends. Distribution.-Corpus Christi Bay. 184. N avicula subcarinata Hendey (Plate 9, Fig. 184). Hendey (1951, 50, 10, 2, 3). N. lyra v. subcarinata Grunow in A.S.A. ( 1875, 2, 5) . Cells solitary; valves elliptical with somewhat rostrate ends; in girdle view, axial area elevated, particularly at ends. Distribution.-Lower Laguna Madre, Matagorda Bay; Pensacola (Florida) . 185. N avicula subdiffusa Hustedt (Plate 9, Fig. 185) . Hustedt (1955, 24, 8, 22). Valves broad, linear with cuneate or produced ends; raphe straight with hooked termi­nal pores; axial area linear-lanceolate; central area dilated; striae at right angles to margins, punctate, puncta closer near margins otherwise tend to be irregular. Distribution.-Aransas Bay. 186. Navicula viridula Kiitzing (Plate 9, Fig. 186). Kiitzing (1844, 91, 30, 47), Cleve (1895, 16), Peregallo (1908, 12, 21, 24). Valves lanceolate with produced apices; axial and central areas narrow, striae parallel, slightly radiate at center. Distribution.-Baffin. Aransas, Copano and Galveston Bays. 187. NavU:ula weissflogii (Grunow) Cleve (Plate 9, Fig. 187). Cleve (1894, 152) , Boyer (1927, 375), A.S.A. (1934, 397, 42). Brebissonia weissflogii Grunow in Cleve, 1878, 7, 10. Valves rhomboid with obtuse ends; raphe with distinct median and terminal pores; axial area indistinct, central area elongate; striae transverse in the middle, radiate at ends, punctate, puncta forming undulate longitudinal rows. Distribution.-Lower Laguna Madre, Aransas, Copano and San Antonio Bays. 188. l\'avicula yarrensis Grunow (Plate 9, Fig. 188). Grunow (in A.S.A., 1876, 46, 1-6), Boyer ( 1927, 418) . Valves elliptic-lanceolate with acute ends; axial area narrow, widened centrally; striae radiate in the middle, slightly convergent and closer at ends. Distribution.-Laguna Madre, Corpus Christi, Copano, Matagorda and Galveston Bays; Florida Gulf. 189. NavU:ula zostretii Grunow (Plate 10, Fig. 189). Grunow ( 1860, 528, 4, 23), A.S.A. ( 1875, 4 7, 42-44). Vah-es elongate-lanceolate with rounded, acute ends; raphe straight; axial and central areas narrow; striae coarse, radiate. Distribution.-Laguna Madre, Corpus Christi and Matagorda Bays; associated with Diplanthera in the Cut, Laguna Madre. 190. Navicula elegans W. Smith (Plate 10, Fig. 190). W. Smith ( 1853, 1, 49), Boyer ( 1916, 31, 2; 1927, 418). Valves broadly elliptic-lanceolate with cuneate ends; raphe straight; axial area nar­rower in the middle and at ends, central area slightly dilated; striae consisting of rows of rectangular puncta at an angle to line of striae; striae radiate, closer at center and at ends. Distribution.-Aransas Bay. Genus NITZSCHIA Hassel, 1845 em. Grunow, 1880 Frustules free, enclosed in sheath or in filaments; valves with keel bearing the raphe, keels diagonally opposite; keel puncta variable. 191. Nitzschia acicularis (Klitzing) W. Smith (Plate 10, Fig. 191 a,b). W. Smith (1853, 43, 15, 122), A.S.A. (1921, 335, 13-17). Synedra acU:ularis Klitzing ( 1844, 63, 4, 3) . Valws aciculate lanceolate, with awns about the length of the median part; striae fine, keel puncta even. Distribution.-Mat_agorda Bay. 192. Nitzschia constricta Ralfs (Plate 10, Fig. 192). Ralfs (in Pritchard, 1861, 780) , A.S.A. (1921, 33·3, 18) . Valves slightly constricted in the middle with rounded and slightly produced ends; central fold marked; valve surface punctate in transverse rows but forming an hexa­gonal pattern; keel puncta coarse, even. Distribution.-Matagorda Bay. 193. Nitzschia distans Gregory (Plate 10, Fig. 193 a, b). Gregory (1857, 58, 6, 103), Hustedt (1921 in A.S.A., 334, 1, 2), Boyer (1927, 512). Valves linear-lanceolate, with acute, tapering ends; striae fine, transverse, keel puncta irregular, more distant towards ends. Distribution.-Aransas Bay. 194. Nitzschia gracilis Hantzsch (Plate 10, Fig. 194). Hantzsch (1859, 40, 6--8), Hustedt in A.S.A. (1924, 349, 34-37) . Valves fusiform, slender, slightly sigmoid; striae somewhat coarse, marginal longi­ tudinal fold more or less hyaline; keel puncta regular, conspicuous. Distribution.-Laguna Madre, Aransas Bay, Matagorda Bay. 195. Nitzschia granulata Grunow (Plate 10, Fig. 195). Grunow (1880, 395, 12, 7), A.S.A. (1924, 330, 4-9), Boyer (1927, 496). Valves elliptic to semi-lanceolate; striae in double rows on keel margin; puncta on valve surface in transverse rows, large, more distant in center. Distribution.-l"pper Laguna Madre, Aransas Bay, San Antonio Bay. 196. Nitzschia hungarica Grunow (Plate 10, Fig. 1%). Grunow 0862, 568, 12, 31), A.S.A. (1924, 331, 6-13), Boyer (1927, 498). Valves linear-lanceolate narrower in the center, ends rostrate; longitudinal fold marked; striae transverse, coarse; keel puncta coarse. Distribution.-Lower and Upper Laguna Madre, San Antonio, Matagorda, Baffin, Ar­ ansas and Galveston Bays; Pensacola Bay, Florida. 197. Nitzschia longissima (Brebisson) Ralfs (Plate 10, Fig. 197). Ralfs in Pritchard ( 1861, 783). Ceratoneis longissima Brebisson in Kiitzing ( 1849, 891). Cells solitary; frustules spindle-shaped with long, usually curved awns; keel puncta even; one chromatophore extending into awns. Distribution.-Aransas and Matagorda and Galveston Bays. 198. Nit:.schia lorenziana Grunow (Plate 10, Fig. 198 a,b). Grunow (in Cleve &Grunow, 1880, 101) , Boyer (1927, 524). Valves narrow, fusiform, sigmoid with ends pointing in opposite directions, blunt; keel puncta irregular, the two median distant; striae distant in the middle, closer at ends. Distribution.-Laguna Madre, Aransas Bay, Matagorda Bay. 199. Nitzschia mediterranea Hustedt (Plate 10, Fig. 199). Hustedt in A.S.A. (1921, 331, 22). Vah·es broad, constricted in the middle, with obtuse, produced ends; raphe excentric; keel puncta marked; fold strong; surface punctate, puncta in diagonal, transverse and longitudinal arrangement. Distribution.-l"pper Laguna Madre, Aransas and Matagorda Bays. 200. Nitzschia obtusa W. Smith (Plate 10, Fig. 200 a,b). W. Smith (1853, 39, 13, 109), Boyer (1916, 121, 39, 16; 1927, 516), A.S.A. (1921, 336, 20, 21, 352, 6, 7). Valves sigmoid, sides straight, curved oppositely at the ends; keels excentric; inflexed in the middle; two median keel puncta distant. Distribution.-Laguna Madre, Galveston Bay; Pensacola (Florida). 201. Nitzschia palea (Kiitzing) W. Smith (Plate 10, Fig. 201). W. Smith (1856, 99), Boyer (1916, 122, 32, 15 ; 1927, 521),A.S.A. (1924, 349, 1-10). Synedra palea Kiitzing) W. Smith (Plate 10, Fig. 201). Valves linear-lanceolate, ends slightly rostrate; striae very fine, keel puncta regular. Distribution.-Lower and Upper Laguna Madre, Baffin and Galveston Bays. 202. Nitzschia panduriformis Gregory (Plate 10, Fig. 202 a,b) . Gregory ( 1857, 529, 14, 102) , Hustedt in A.S.A. (1924, 331, 19, 21). I Valves panduriform, apices acute; longitudinal fold marked; striae transwrse and oblique; keel puncta coarse. Distribution.-Lower Laguna Madre, Aransas, Corpus Christi and Matagorda Bays. 203. Nitzschia plana W. Smith (Plate 10, Fig. 203). W. Smith (1853, 42, 15, 114), Boyer (1916, 117, 32, 2; 1927, 500), A.S.A. (1924, 330, 3). Valves linear, slightly constricted in the middle; apices acute, may be slightly pro­duced; longitudinal fold marked, distant from keel; striae irregular, interrupted; keel puncta strong, oblong. Distribution.-Aransas and Galveston Bays. 204. Nitzschia punctata (W. Smith) Grunow (Plate 10, Fig. 204). Grunow in Cleve & Grunow (1880, 69) , A.S.A. (1924, 330, 10-14). N. compressa Boyer (1916, 116, 39, 7; 1927, 496). Valves elliptic-lanceolate with produced ends; striae transverse, coarsely punctate; longitudinal line broad; keel puncta regular. Distribution.-Laguna Madre, Aransas, Matagorda and Galveston Bays. 205. Nitzschia sigma (Kiitzing) W. Smith (Plate 10, Fig. 205). W. Smith ( 1853, 39, 13, 108) , Boyer ( 1916, 121, 39, 13; 1927, 514). Synedra sigma Kiitzing (1844, 67). Valves linear, ends sigmoid, tapering to the subacute ends; keel excentric; striae fine, punctate. Distribution.-Laguna Madre, Aransas, Matagorda and Galveston Bays. 206. Nitzschia silicula Hustedt, 1955 (Plate 10, Fig. 206). Hustedt (1955, 14, 16, 19, 20). Valves lanceolate with very slightly rostrate, subacute ends; fold slight; keel ex cen­ tric; keel puncta indistinct; transverse striae crossed by longitudinal striae. Distribution.-Laguna Madre, Baffin, Aransas, San Antonio and Galveston Bays; St. An­drews Bay (Florida) . 207. Nitzschia tryblionella Hantzsch Hantzsch (1859, in Rabenhorst, 984), A.S.A. (1921, 3S2, 14), Boyer (1916, 116, 32, 8; 1927, 495). Valves elliptic-lanceolate with subacute ends; longitudinal fold well marked; keel very excentric; striae coarEe, transverse, puncta between striae indistinct. v. victoriae (Grunow) van Heurck (Plate 10, Fig. 207) . Grunow in Cleve & Grunow (1880, 69). Valves broad, sometimes slightly constricted, ends cuneate, striae coarse. Distribution-Laguna Madre, Aransas, Matagorda and Galveston Bays; Biloxi (Missis· sippi). 208. Nitzschia sp. (Plate 10, Fig. 208). Valves linear, ends evenly rounded; longitudinal fold close to margin; striae coarsely punctate, transverse; keel puncta not distinct. Distribution.-Aransas Bay. Genus OPEPHORA Petit, 1888 Frustules rectangular; valves cunieform, ends unlike; pseudoraphe present; striae transverse, punctate. 209. Opephora pacifica (Grunow) Petit (Plate 10, Fig. 209). Petit (1888, 131), Boyer (1916, 43, 10, 18; 1927, 182), Hustedt (1955, 13, 4, 47-49). Fragilaria pacifica Grunow (1862, 373, 6, 19) . Valves elongate, pyriform; pseudoraphe lanceolate; striae punctate, coarse, slightly alternate. Distribution.-Baffin and Aransas Bay; St. Andrews Bay, Florida. 210. Opephora schwartzii (Grunow) Petit (Plate 10, Fig. 210). Petit (1888, 38, 346), Boyer (1916, 43, 10, 16; 1927, 182). Fragilaria schwartzii Grunow ( 1863, 143, 5, 7). Valves linear-ovate, ends rounded; pseudoraphe lanceolate; costae transverse, punc­ tate; fine areolae between costae. Distribution.-Upper Laguna Madre, Aransas, Galveston Bays; St. Andrews Bay (Florida). Genus PINNULARIA Ehrenberg, 1843 Valws linear with rounded ends; axial area broad, raphe curved ; central and termi­nal areas large; costae smooth, transverse or radiate or a combination of both. 211. Pinnularia viridis (Nitzsch) Ehr. Ehrenberg (1838, 182), A.S.A. (1875, 45, 9-11) , Boyer (1927, 446). Bacillaria viridis Nitzsch ( 1817, 97). Valves linear-elliptic with rounded ends; raphe complex; axial area narrow at apices widened towards the middle; costae slightly divergent in the middle, convergent at ends, crossed by a broad band. v. rupestris (Hantzsch) Cleve (Plate 10, Fig. 211). Cleve ( 1895, 92) . Striae finer than type. Distribution.-Matagorda and Galveston Bays. Genus PLAGIOGRAMMA Greville, 1859 Frustules rectangular, in chains or free; valves linear-elliptic to lanceolate with 2 me­dian and 2 terminal costae, and one median and two terminal hyaline spaces. 212. Plagiogramma obseum Greville (Plate 10, Fig. 212). Greville ( 1865), Boyer ( 1916, 43, 10, 12). Valves biconical with rounded ends; central area hyaline, transverse, apical areas rounded; pseudoraphe evident; surface with punctate striae forming radial and longi­tudinal rows. Distribution.-Aransas Bay, Matagorda Bay. 213. Plagiogramma wallichianum Greville (Plate 10, Fig. 213). Greville ( 1865, 13, 1) , Boyer (1927, 179) , Hustedt ( 1955, 11, 4, 29). Valves linear with rounded ends, pseudoraphe narrow or absent; central space rec­tangular, terminal spaces large; striae at right angles, evident also in central and term­inal spaces. Distribution.-Lower Laguna Madre, Aransas Bay, Matagorda Bay; Pensacola Bay (Florida). Genus PLEUROSIGMA W. Smith, 1852 Valves lanceolate-sigmoid; axial area very narrow; central area small; raphe more or less sigmoid. There seems no valid reason for separating Pleurosigma and Gyrosigma solely on the striation of the valves, especially as there are much greater differences in valve structure in other genera, e.g., Mastogloia and Navicula which contain more species, and are not thus divided. The two genera are here considered as one. 214. Pleurosigma angulatum (Queckett) W. Smith (Plate 10, Fig. 214, a,b). W. Smith (1853, 65, 21, 205), Boyer (1916, 74, 22, 61; 1927, 421). N avicula angulata Queckett ( 1848, 438, 7, 47) . Valves sigmoid-rhomboid, with at times a definite angle on the valve margin adjacent to the central nodule; raphe sigmoid, central; central nodule small, more or less rhombic; valve surface with fine, oblique cross-hatching, which become transverse-longitudinal at apices. This is not shown in Smith's drawing, or mentioned in his description, but occurs in specimens from the type locality and in the Texas specimens. It does not occur in Australian and New Zealand specimens. Distribution.-Upper Laguna Madre, Aransas and Matagorda Bays. 215. Pleurosigma (Gyrosigma) balticum (Ehr.) W. Smith (Plate 10, Fig. 215 ). W. Smith ( 1853, 66, 22, 207), Boyer ( 1916, 75, 23, 2; 1927, 456). Valves linear with sigmoid extremities; raphe sigmoid and slightly curved close to central nodule; striae longitudinal and transverse. Distribution.-Laguna Madre, Aransas and Matagorda Bays. 216. Pleurosigma (Gyrosigma) beaufortianum Hustedt (Plate 10, Fig. 216). Hustedt (1955, 34, 10, 7, 8). Valves sigmoid, linear-lanceolate with acute ends; raphe central, sigmoid; central nodule extended to a stauros; striae transverse and longitudinal, the latter very fine; the shape varies considerably as shown by Hustedt's and the present illustrations. Distribution.-Aransas and Galveston Bays. 217. Pleurosigma (Gyrosigma) distortum W. Smith. W. Smith (1855, 7, 1, 10). Valves sigmoid, margins evenly rounded, ends acute, sharply rounded; Etriae trans­verse and longitudinal. v. diaphana (Cleve) Peragallo (Plate 10, Fig. 217). Peragallo (1908, 173, 34, 27) . G. diaphana Cleve ( 1894, 115, 6, 6). Ends more produced than in type. Distribution.-Aransas Bay, Galveston Bay. 218. Pleurosigma distinguendum Hustedt (Plate 11, Fig. 218 a,b). Hustedt (1955, 36, 11, 3-5). Valves lanceolate, with sub-acute, rounded ends slightly produced; raphe sigmoid, ex­centric towards ends with extremities strongly curved in opposite directions; axial and central areas narrow; striae oblique, equidistant; these specimens have a more sigmoid raphe with less undulation than those figured by Hustedt. Distribution.-Galveston Bay. 219. Pleurosigma (Gyrosigma) fasciola (Ehrenberg) W. Smith (Plate 11, Fig. 219). W. Smith ( 1853, 67, 21, 211), Boyer ( 1927, 463) . Valves sigmoid, extremities drawn out into long, curving beaks, raphe almost straight, central to beaks, then sigmoid; striae transverse and longitudinal. Distribution.-Upper and Lower Laguna Madre, Aransas and Matagorda Bays. 220. Pleurosigma formosum W. Smith (Plate 11, Fig. 220). W. Smith 0853, 63, 20, 195), Boyer (1916, 73, 22, 5; 1927, 467). Valves sigmoid; raphe strongly sigmoid, sweeping from central nodule towards valve margin, giving a very twisted appearance; striae oblique forming a diamond-shaped network. Distribution.-Laguna Madre, Baffin, Aransas, Matagorda and Galveston Bays. 221. Pleurisigma naviculaceum Breb. (Plate 11, Fig. 221) . Brebisson (1867, 17), Boyer (1916, 74, 22, 6; 1927, 471). Valves lanceolate, slightly sigmoid at the subacute ends; raphe nearly central, sigmoid near ends; central nodule dilated transversely; striae oblique in 2 directions. Distribution.-Aransas and Matagorda Bays. 222. Pleurosigma (Gyrosigma) peisonis Grunow (Plate 11, Fig. 222 a,b). Grunow (1860, 562, 6, 8), Hustedt (1955, 10, 4). Valves with parallel sides, inner and outer margins both sigmoid; raphe sinuate, 278 A Study of the Diatom Flora of Fresh Sediments of the South Texas Bays median, then approaching outer margin; striae coarse, transverse and longitudinal. Distribution.-Matagorda Bay; Pascagoula (Mississippi). 223. Pleurosigma (Gyrosigma} simile Grunow (Plate 11, Fig. 223). Grunow (1860, 56), Boyer (1916, 76, 23, 4; 1927, 457). Valves linear, one margin sharply rounded giving a bluntly sigmoid appearance to the valve; raphe sigmoid at ends; striae transverse and longitudinal. Distribution.-Aransas and Matagorda Bays. Genus PODOSIRA Ehrenberg, 1840 Frustules spheroidal to lenticular; single or in pairs; valve surface with fasciculate areolae. 224. Podosira hormoides (Mont.) Kiitzing (Plate 11, Fig. 224 a,b) . Kiitzing (1844, 52, 28, 5, 29, 84), Hustedt (1928, 283, 123). Trochiscia moniliformis Montagne (1837, 349). Melosira hormoides Montagne (1839, 2). Frustules lenticular with strongly convex valves; without valve mantle; valve surface with fasciculate rays of areolae. Distribution.-Aransas and Matagorda Bays. Genus PYXIDICULA Ehrenberg, 1833 Frustules globular, solitary or in pairs; valves more or less hemispherical, areolate, without spines. 225. Pyxidicula cruciata Ehrenberg (Plate 11, Fig. 225). Ehrenberg (1833, 3, 8), Boyer (1916, 19, 38, 8). Cells solitary or in pairs; valves hemispherical with large, hexagonal areolae, largest at center, uniform towards valve margins; no constriction between valve and girdle; no spines, spinules or processes. Distribution.-Baffin, Aransas and Matagorda Bays. Genus RHABDONEMA Kiitzing, 1844 Frustules rectangular, in chains or single; containing a number of septa; surface costate, costae united by cross ribs. 226. Rhabdonema adriaticum Kiitzing (Plate 11, Fig. 226). Kiitzing (1844, 126, 18, 7), Boyer (1927, 150). Cells in ribbons, shortly stipitate; frustules in girdle view square to oblong with rounded corners, multiseptate, septa with 3 foramina in valve view; valves linear with rounded ends; surface in girdle view costate, costae united by cross ribs, in valve view transversely striate, striae with hyaline areas at each end. Distribution.-Aransas Bay. Genus RHAPHONEIS Ehrenberg, 1844 Frustules linear in girdle view, lanceolate, to elliptic, lanceolate in valve view; pseudo· raphe distinct. 227. Rhaphoneis amphiceros Ehr. (Plate 11, Fig. 227 a). Ehrenberg (1884, 87), A.S.A. (1911, 269, 44-45), Boyer (1927, 190). Valves broadly lanceolate to semicircular, with produced ends; striae moniliform, radiating, granulate, the granules in longitudinal lines. Distribution.-Laguna Madre, Aransas Bay. 228. Rhaphoneis castracanei Grunow (Plate 11, Fig. 228). Grunow (in van Heurck, 1880-85, 36, 28), A.S.A. (294, 35-37) . Valves hexagonal, with concave sides; pseudoraphe linear-lanceolate; puncta coarse forming curved striae. Distribution.-Aransas Bay. 229. Rhaphoneis surirella (Ehrenberg) Grunow (Plate 11, Fig. 229 a). Grunow in van Heurck (1880-85, 36, 26, 27a). Zygoceros surirella Ehrenberg ( 1840, 4, 12). Valves elliptical, ends slightly acute; pseudoraphe narrow, slightly wider at ends; puncta irregularly spaced in middle. Distribution.-Lower Laguna Madre. v. australis Petit (Plate 11, Fig. 229 b,c). Petit (1877, 174, 4-6). Dimerogramma australe Boyer (1927). Valves elliptical to linear elliptic, ends acute; pseudoraphe broad, slightly constricted in the middle; striae coarse, punctate, radiate at ends, transverse in the middle, forming longitudinal rows. Distribution.-Aransas Bay. Genus RHOPALODIA Mliller, 1885 Frustules in girdle view linear to clavate; valves reniform to lunate; raphe on convex edge, often not visible; the separation of this genus from Epithemia is questionable. 230. Rhopalodia gibberula (Ehrenberg) 0. Mliller (Plate 12, Fig. 230 a-d). Boyer (1927, 450). Eunotia gibberula Ehrenberg ( 1843, 125) . Frustule elliptic-lanceolate; valves lunate, ends may be rostrate, very variable; costae distant with intermediate rows of fine puncta. Distribution.-Upper and Lower Laguna Madre, Baffn, Aransas, Corpus Christi, Mata­ gorda and Galveston Bays (rare in upper waters of the last two) . 231. Rhopalodia musculus (Klitzing) 0. Mliller (Plate 11, Fig. 231 a). 0. Mliller (1895, 278), A.S.A. (1905, 255, 1-12). Epithemia musculus Klitzing (1844, 33, 30, 6). Boyer (1927, 490). Frustules elliptical with acute, slightly truncate ends; costae well marked, alternating with rows of fine punctae striae. Distribution.-Aransas Bay. v. constricta Breb. (Plate 11, Fig. 231b,12, 231 c). Brebisson in W. Smith (1853). Valves slightly constricted in the middle. Distribution.-Laguna Madre, Baffin, Aransas, rare in Matagorda and Galveston Bays. Genus SKELETONEMA Greville, 1865 Frustules discoid, forming chains united by a series of marginal filaments which may be as long as cells and are joined by nodes. 232. Skeletonema costatum (Greville) Cleve (Plate 12, Fig. 232) . Cleve ( 1878, 18) . M elosira costata Greville ( 1866, 8, 3-6) . Chains thin, usually straight; cells lenticular to cylindrical, joined by a row of straight, interlocking marginal spines. Spores brown, spherical bodies. Distribution.-Galveston Bay (common in sediments of this area). Genus STAURONEIS Ehrenberg, 1843 Valves lanceolate; raphe straight; axial area straight, central area forming a stauros. 233. Stauroneis phoenicenteron (Nitzsch) Ehrenberg (Plate 12, Fig. 233). Ehrenberg (1843, 134) , Boyer (1927, 421), Hustedt (1937, 766, 1118). Bacillaria phoenicenteron Nitzsch (1817, 92, 4). Valves lanceolate with obtuse ends, may be slightly produced; axial area linear, stauros transverse; puncta in longitudinal and oblique rows. Distribution.-Lower Laguna Madre, Aransas Bay; Pensacola Bay, ---------+­ 100• 95' 90• Fie. 4. Prevailing winds of the Gulf Coast. From U.'S. Congress (1953). The wind rose in each 5° square shows the yearly average winds that have prevailed within that square. The arrows fly with the wind. The length of the arrow measured from the outside of the circle as demonstrated on the scale below gives the per cent of the total number of observations in which the wind has blown from or near the given direction. The number of feathers shows the average force of the wind on the Beau­fort scale. The figure in the center gives the percentage of calms. Wind roses for 18-month period ending July, 1946 were compiled from "Pilot Charts of the North Atlantic Ocean" issued by the l-Iydrographic Office, U.S.N. WINO DIRECTIONS SWELL DIAGRAMS "'T"'!MUQo-...Sf>t: ~Oll..:w.JKtoU'o _..,. .,., ... WJ_•~ COllUIOIT>llClO'ISI _...OT l&Tin.ot: I'S'~ ~>(lOC.•~ ~"~"-­ -LOIO' "'1.U l• -6oUTl a..-··-01 ..-., ,o• • '"""$WO.U lo-t:• •IH(T) Fie. 5. Wind diagrams of the Gulf Coast. Fie. 6. Swell diagrams of the Gulf Coast. From From U.S. Congress (1953). Based on hourly U.S. Congress ('1953). readings 1905--1944 by the U.S. Weather Bureau. Just below Mineral Wells the Brazos encounters Cretaceous rocks and continues on these for some distance below Waco. The Cretaceous outcrop consists chiefly of lime­ stone and marl of the Comanche series and the Gulf series. At Waco the Brazos crosses the Balcones fault zone and passes onto the Gulf Coastal Plain, which is composed of Tertiary sandstone and clay with a few thin limestone beds. At mile 160 the Brazos passes into the outcrop of the Quaternary Lissie and Beaumont clays and at Columbia, 40 miles from the mouth, into Recent alluvium. The maximum width of the drainage area is roughly 120 miles in central Texas, whereas at the mouth it narrows to about 10 to 15 miles. Brazos River Hydrology. The gradient of the Brazos River ranges from 6 feet per mile in the High Plains, where it heads at 4000 feet to essentially zero in its lowest reaches. Deussen ( 1924, p. 13) presents a longitudinal midstream profile of the Brazos River from Waco, Texas, to the mouth, and it is from this profile that the following observa tions concerning the stream gradient are made. From mile 430 (Waco) to mile 260 (Eocene-Miocene contact) the gradient is locally variable but averages 1.27 feet per mile, and the Cretaceous and Eocene beds, across which the river flows in this belt, have a regional dip of from 40 to 90 feet per mile. From mile 260 to mile 160 (Pliocene-Quaternary contact) the gradient is 0.65 feet per mile, the Miocene and Pliocene beds traversed have a regional dip of from 30 to 40 feet per mile. From mile 160 to mile 50 the gradient is 0.92 feet per mile in the Quaternary beds, which have a regional dip of from 20 to 30 feet per mile. Finally, the gradient is less than 0.1 feet per mile in the essentially flat lying Recent deposit from mile 50 to the Gulf, this portion of the stream course being tidal. Several interesting observations may be made from the above calculations. First, a progressive decrease in the regional dip of the formations traversed is reflected in the stream gradient. Second, ultimate base level has progressed 50 miles upstream, the knick­point having traveled 10 miles beyond the Quaternary-Recent contact. Third, when the overall gradient from mile 160 to mile 0 is calculated it is found to be 0.66 feet per mile and thus is identical to that of mile 160 to mile 260. This same gradient is maintained up to mile 305, the base of the Upper Eocene. Therefore, an original uniform gradient existed for the lower 305 miles of the Brazos prior to headward transgression of base level. Fourth, a second knickpoint is observed at mile 160, the Pliocene-Quaternary con­tact. The riwr profile is a result of river filling and cutting. During the last major lowering of sea level, at the close of Pleistocene time, the Brazos River entrenched itself across the Coastal Plain in a valley almost 200 feet deep and built a large offshore delta. The present Brazos River filled in its old valley almost completely and is in the process of building a new delta. The existing channel, therefore, lies in Recent fill, which the Brazos itself deposited. River width and depth are locally variable hut in general fit the idealized pattern rather well. Depth increases toward the mouth, being 25 to 30 feet below mean low tide at the Gulf. Width also increases toward the mouth to more than 500 feet. Flood plains are best developed in the last few miles before the Brazos enters the Gulf, extend­ing roughly 5 miles on either side of the main channel. Natural levees on this section of the river are at the most 1 foot high. Rises at the mouth of the Brazos are in the order of inches, so that at the gauging station on the Intracoastal Waterway locks, floods are re­corded by velocities rather than by measurements of increased river height. Table 1 is compiled from Bloodgood and Mortensen (1951, p. 57-58) and summar­izes discharge data for the Brazos River and other ·major Texas streams. The important figures are the yearly amount of silt in tons and the percentage of silt by weight. The TABLE l Summary of silt data for some of the major Texas streams for water year ending September 3, 1950 (Bloodgood and Mortensen, 1951) Total Average Average Net length record runoff or stream amount of ~ill S;t1 by weight drainage Million Million Thousand Stream Silt station Years acre.feet tons Per cent square miles Brazos Richmond 26 5.69 34.74 0.448 34.81 Colorado Columbus-E. Lake 7 3.17 8.99 0.209 '29.141 Nueces Three Rivers 23 0.67 0.76 0.083 15.60 Rio Grande Roma 14 4.17 19.20 0.338 157.20 Sabine Ruliff l 11.41 5.77 0.037 9.44 Trinity Romayor 14 6.66 6.62 0.073 17.19 average figure of 0.448 percent silt by weight for the Brazos is almost double that of any other Texas stream and is roughly 17 times larger than that for the Mississippi River (Odem, 1953a, p. 19) . Referring again to Bloodgood and Mortensen (1951, p. 57) it appears that the con­struction of Possum Kingdom Dam in 1942 served to trap silt from the upper reaches of the river, thus subtracting the upstream silt contribution from the river load. Prior to construction of the dam, Glen Rose gauging station recorded 0. 794 per cent silt by weight, while Possum Kingdom Dam gauging station (below the lake) now records 0.016 per cent silt by weight. However, the pertinent fact is that the eventual discharge of silt into the Gulf has remained almost constant over the last 26 years (as recorded at Richmond gauging station). It may be concluded that most of the material being dumped into the Gulf of Mexico by the Brazos River is a product of bank erosion between Waco and the mouth. Subaerial Delta.-The present subaerial delta of the Brazos River has been forming only since 1929 when the mouth of the river channel was diverted to a point southwest of the then existing mouth at Freeport Harbor. Since 1880 the lower 5 miles of the Brazos River course have been used as a salt water port. Freeport Sulphur Company shipped large tonnages of sulphur mined from Bryan Mound, just to the south of Free­port, until recently when it shifted its operation to Hoskins Mound from which the sulphur now moves by rail to Galveston. At one time 70 per cent of the U. S. produc­tion and 35 per cent of the world production of sulphur moved through Freeport Har­bor. Since the diversion of the lower 7.3 miles of the Brazos River to the southwest (making the harbor tidal), Dow Chemical Company has made use of the harbor facilities. Before 1929, with every rise on the Brazos the harbor silted up to non-navigable depths and had to be dredged. Considering the silt load carried by the Brazos during rises, 5 to 10 per cent by volume (Fox, 1931), and the fact that rises occur on an average of 5 times a year (IO times a year from 1920 to 1924, Odem, 1953a, p. 22) , the prob­lem can be envisioned. A reduction in harbor depth of from 25 feet to 12 feet during one flood is reported. Shoaling at the river mouth was another difficulty; channels shifted frequently and constant dredging was necesrnry. In 1928, the decision was made to make Freeport a tidal harbor by diverting the river at a point above Freeport and leaving the old channel as a tidal lagoon in the hope that this would eliminate or cut down maintenance costs. By September, 1929, the diversion had been accomplished and the Brazos River then entered the Gulf of Mexico 6.5 miles southwest of Freeport Harbor. The new channel was 5.5 miles long (measured from the point of diversion 7.3 miles above the original mouth) and trended for the last 6000 feet at an angle of 63° to the shoreline. The upper portion of the di­versionary channel was dredged to a width approximately equivalent to that of the river above the point of diversion ( 450 feet), while the lower extent was only about half this wide. Dredging was carried on to a depth of 12.5 feet with the spoil used to build levees on either side. A steel-reinforced earthen dam blocks off Freeport Harbor and completes the diversion. The dredging operation served only to act as a guide for the river, which was left to scour its own channel. This the Brazos has accomplished rapidly, and flooding has been largely eliminated. Although rises do not cause the river to leave its banks, the area is inundated daily by high tide causing large marshy flats inland from the beach. The new channel is showing no tendency to establish meanders such as existed in the old channel. The effectiveness of marine agents and the dynamic state of shoreline development may be seen in a study of the shoreline adjacent to Freeport Harbor (Fig. 7). In 1887, prior to construction of jetties, the shoreline configuration was roughly comparable to that existing presently at the mouth of the diverted Brazos and the 3 fathom contour was well offshore. Following construction of the jetties between 1889 and 1908, rapid accre· tion occurred in the areas now protected from longshore currents on either side of the jetties. Prograding of the shoreline and seaward shifting of the 3 fathom contour on the east side of the jettied channel lagged behind that on the west side because of the drifting of the silt load, in deeper water, to the west. These conclusions may be inferred from the 1932 shoreline and 3 fathom contour. Southwest of the harbor jetties the shoreline advanced 4000 feet and the 3 fathom contour advanced 5000 feet. The cor­responding shoreline and 3 fathom contour northeast of the jetties advanced 1800 and 1500 feet respectively. These data for 1932 are construed to represent maximum de· velopment of the Old Brazos River delta, as this is approximately the date of the diversion. The abrupt cessation of river current and silt load caused by the 1929 diversion evoked a rapid change in the shoreline configuration between the harbor and the new river mouth. By 1946 the shoreline in this area had retreated 1300 feet and the 3 fathom contour occupied its 1887 position. Conditions on the northeast side of the jetties in 1946 show essentially no change from 1932. The 1952 shoreline, (not shown on Fig. 7) , shows a further regression to a position coincident with the original 1887 shoreline (U.S. Congress, 1957), thus completing the cycle. Following diversion in 1929, and the flood of 1930, a depth survey of the nearshore ShaJ,low Marine Sediments Offshore from the Brazos River, Texas area was made (Fox, 1931). From this survey maximum deposition was found to be about one-fourth mile offshore, well in front of the channel mouth. Depth survey"s were subsequently made for the following 4 years by the Corps of Engineers in an effort to ascertain whether the channel would maintain itself or whether it would clog up. These surveys indicated that the crest of the delta was moving seaward at a rate suf­ficient to keep the channel clear. The 1929 bathymetric map of the area off the mouth of the diversion channel (prior to diversion) shows a uniform depth increase offshore, with contours parallel to the shoreline (Fig. 8). From bottom contour maps for succeeding years the following ob­servations are made. By 1931 (Fig. 9) the delta crest had moved seaward 3000 feet (2000 feet since 1930) and was 2 feet below sea level. Slight deposition over a wide area is shown by t}:ie 16 foot contour. The channel has already begun to swing south­east and the steepest face of the delta is also in this direction, as indicated by the closer spacing of the 6 through 14 foot contours. Irregularities in the contour configuration farther offshore are caused by rip currents. By 1932 (Fig. 10), or 3 years after the diversion, the river deepened its channel and had developed a submerged distribution system, while the crest of the delta had ad­vanced 3000 feet and was clearly" defined by steep circumferential contours. Increased areal extent of the delta is obvious. Portions of the delta became subaerial in 1933 (Fig. 11) and a symmetrical pattern had developed. Again, the southeastward trend of the main distributary channel has been progressively emphasized. Although areal extent has not increased significantly since 1932, the slope off the crest has become much more uniform. Most of the deposi­tion during this interval has been nearshore, resulting in elevation of this part of the delta above water. The changes in the delta are less clear on the map for 1934 (Fig. 12). Areas of the delta formerly subaerial are once again submarine: the main channel is not as well defined, and deposition has shifted in part to the adjacent northeast region. A less uni­form slope and an advance 1500 feet seaward of the delta is partly due to a redistribu­tion of sediment rather than any great increase of new deposits. Pronounced smoothing results in a marked parallel configuration of the delta face with the shoreline. lsopach maps, employing the 1929 bottom contour as zero datum, indicate delta growth even more clearly. Initial rapid buildup establishes the channel and gives the delta rough form (Fig. 13), and when areal extent and vertical thickening have reached a balance, determined by the environment (Fig. 14) , growth proceeds in a uniform manner in three dimensions (Fig. 15) . A flattening and gradual loss of character of the delta configuration developed by 1934 (Fig. 16). The orientation of the main channel has now shifted from southeast to due south and channels parallel to shore are well developed. The zero contour is con­siderably" contracted, indicating a loss of areal extent, thickening has not only ceased but has actually decreased, and a loss in volume has probably occurred. Development of the delta, as observed in the contour and isopach maps, may be con· veniently explained in terms of the interaction of river current and silt load, and wave, tide, and current action (in other words, the environment). Assuming marine agents (waves, tides, and currents) to be reasonably uniform for the years 1929-1934, the ex­planation must be sought in variations in the Brazos River. Table 2 summarizes silt data Frc. 10. Bottom contour map off the mouth of the Brazos River for 1932. From Odem (1953a). Frc. 11. Bottom contour map off the mouth of Frc. 12. Bottom contour map off the mouth of the Brazos River for 1933. From Odem (1953a). the Brazos River for 1934. From Odem (1953a). for the Brazos River for the 4 years following the diversion. Water years refer to a calendar year of discharge measurements extending from October 1 to September 30. Hydrographic surveys of the area were made in the early summer months, so that the 1931 survey represents conditions mmlting mainly from the 1929-1930 water TABLE 2 Summary of silt data for Brazos River watershed at Richmond gauging station (Bloodgood and Mortensen, 1951) Discharge SHt load Average percentage of stream of stream of dry sill by weight '\\"aler )'·ear acre· feel tons acre-feel per cent 1929-30 5,218,900 38,686,330 25,373 0.545 1930-31 5,639,000 27,766,(J(i() 18,212 0.3'62 1931­3'2 8,041,000 63,649,510 41,749 0.582 1932-33 2,563,100 '15,175,520 9,954 0.435 year and so on. Thus, the water year of most abundant discharge, 1931-1932, ac­counts for the greatest development of the delta shown by the hydrographic survey of 1933. The marked decrease in discharge in the water year 1932-1933, correspondingly accounts for a redistribution and grading of the delta by marine agents as shown in the hydrographic survey for 1934. Rapid adjustment to changes in dynamic equilibrium conditions are here illustrated in a graphic fashion. When the Brazos River discharge increased significantly, its share of the energy environment also increased significantly and delta growth accelerated. ConYersely, when the Brazos decreased its discharge, its energy contribution correspond­ingly decreased, and marine agents attained a proportionately larger influence resulting in modification of the delta by these same agents. The constantly accelerated rate of delta accretion since 1931 (75 per cent of the 1952 delta developed since 1942), indicates either that less and less of the silt load of the river is lost to longshore currents, or that longshore currents are unable to operate effectively against so impressive an obstacle and therefore dump their load on the delta. F1G. 13. Isopach map off the mouth of the Brazos RiYer for 1929-'1931. Adapted from Odem (1953a). Fie. 16. Isopach map off the mouth of the Brazos River for 1929-1934. Adapted from Odem (1953a). If at the present time longshore currents are agents of deposition rather than of trans­portation, it is a complete reversal of their original role. Analysis of borings (Odem, 1953a, p. 87-88) reflects a permanent sedimentary record of vertical fluctuations in depositional history of the delta by intrastratification of different textural types. During periods of flood, coarse, poorly sorted material is de­posited rapidly, but at times of low water, marine agents distribute layers of fine clayey and silty material over the entire region. Longshore currents deposit beach material on offshore bars and scour the channels between the bars. Although a major storm or hurricane may completely redistribute the upper fluid sediment layers in a matter of days, the pattern of extensive bottomset beds of fine material (evenly distributed by marine action) and foreset beds of coarser material (deposited by river action) is generally not distributed to the extent that the sequence is not readily identifiable. At the time of the writer's study the subaerial portion of the delta exhibited well de­veloped bars and spits on both sides of the mouth, and had an overall cuspate appear­ance (Bates, 1953, Fig. 20). The main distributary channel is oriented approximately at right angles to the shoreline, an increase of roughly 22° over the original angle of intersection of the diversion channel with the shoreline. Hooked spits and barriers have grown to such an extent that they have enclosed lagoons behind them, and it is in con­nection with these lagoons that the action of tides becomes significant. Daily tides inun­date the lagoonal areas, depositing fine grained material which eventually fills in the lagoons. The result is a more stable configuration of the delta and shoreline. Figures 4 and 10 depict the several agents acting on the delta by means of quantitative energy approximations and explain adequately the symmetrical configuration of the present delta. Effects of longshore currents are not evaluated, but from other data it 326 Shallow Marine Sediments Offshore from the Brazos River, Texas appears that their contribution must be minor. Longshore currents have a dual role of transportation and deposition. Unquestionably, beach sand is being carried longshore in a southwesterly direction as concluded by Bullard (1942, p. 1042) and as indicated by the heavy mineral analysis of this report, but this fact should not be interpreted as signifying erosion and subsequent net removal of material to the southwest. Under uniform conditions only a certain limited amount of material can be transported at any specific time by a longshore current. As the current picks up material for trans­port it must then deposit a corresponding amount. Therefore, the actual net volume transfer of material at such a point may be zero, as is more evident when the mode of transportation of longshore currents is considered. As pointed out previously, longshore currents are primarily agents of transportation, with the evidence indicating that the transported load moves primarily by traction and saltation. To roll or saltate a large sand grain possessing an exposed surface area is much easier than to pick up a very fine silt grain or cohesive clay flake and place it in suspension (Hjulstrjllm, 1939, p. 10-11). Sargent Beach is a case in point; during periods of normal tides and moderate current conditions a thin veneer of sand covers the beach from high tide to some feet below low tide, but during periods of increased activity a hard slippery clay bottom is exposed. Erosion of this clay bottom is proceed­ing very slowly' by a process of vertical caving in chunks, with mud balls being carried up onto the beach. Certainly at Sargent the clay material from the exposed bottom is not being picked up particle by particle and moved in suspension, nor, for that matter, is it even being eroded effectively. Contrast this situation in regard to the clay to the relative ease of movement of the sand veneer overlying it. This same clay bottom is exposed at low tide on either side of the Brazos mouth, its resistance to erosion and transportation accounting for the existence of straight sections of shoreline at these points. Only after enough sand has been deposited to bury the presently exposed clay will the shoreline become curved and fit the configuration of the delta in a more uniform manner. From an examination of Fig. 4, 5 and 6 it may be concluded that almost all wave movement on the average is oriented directly onshore-offshore. This condition could be expected to give rise to locally and seasonally variable littoral drifts of low net magni­tudes. The symmetrical configuration of the Brazos delta and adjacent shoreline, and of the present shoreline on either side of the Freeport Harbor jetties, substantiate this con­clusion, as do wave refraction diagrams for the nearby Caplen, Texas, area (Beach Erosion Board, 1956). Bascom (1954) presents evidence indicating that stream outlets will shift in the direction of low wave attack, which would also be the direction of littoral drift. The main distributary channel of the Brazos River, however, has shifted from the southwest to a south-southeasterly direction, which circumstance, according to Bascom's reasoning, indicates a northeast longshore drift. Direct measurements of littoral currents and measurements of accretion, made by the Corps of Engineers on Galveston Island, have been interpreted by them as showing the existence of locally variable drifts, with frequent reversals of direction being common (U. S. Congress, 1953, p. 22-23). On the other hand, petrologic evidence from Bullard (1942), and from this report (covered in a later section), indicate a net migration of material to the southwest. The nature of the movement of this material is conjectural as far as the study area is con· cerned. Mason (1953, p. 569) stated that for material moved by wave action, as much Shallow Marine Sediments Offshore from the Brazos River, Texas as 80 per cent is moved in the zone between breakers and shore. Evidence presented by Trask (1931) ;in a study of sand movement around promontories in southern California, establishes the movement of sand parallel to shore in depths of water up to 60 feet. From a summary of recent studies concerning the rate of littoral transport (Johnson, 1956, p. 2217) it appears that maximum littoral transport occurs at a certain critical wave steepness which prevails for intermediate or summer waves and not for storm waves. The critical angle of wave approach with the shoreline for maximum littoral transport is approximately 40° (Johnson, 1956, p. 2217), considerably different than the prevailing angle of wave approach for the study area. Sediment characteristics also have an effect on longshore transport. Evaluating all the evidence presented, the conclusion is reached that longshore move­ment of material in this area proceeds at some depth well seaward of the breaker zone. Furthermore some mechanism places this transported material into the zone landward of the breakers where it can be deposited on the beach by local littoral drifting. Longshore currents smooth shorelines by means of transportation and deposition, but the extent of their erosive power in this area is questionable. SAMPLING AND ANALYSES COLLECTION OF SAMPLES Samples were collected in 1955 during the middle summer months when winds and storms are at a minimum. The Institute of Marine Science of The University of Texas, at Port Aransas, Texas, served as a permanent base of operations while field sampling was carried out from Freeport Harbor. The J 673, a 42-foot twin screw diesel launch converted from an Army air-sea rescue boat by the Institute of Marine Science, was employed in the sampling program. Sampling and navigation equipment was installed by the writer and the boat drydocked prior to putting to sea, for which the Mobil Oil Company very generously provided a grant. A Bendix 400-foot, 400 fathom fathometer provided for a continuous depth record of all sample traverses. An outrigger davit was fabricated to handle sampling equipment in combination with a small hand winch. Bottom samples were secured with a Peterson grab sampler, a clam-shell device which is simple in construction and operation, is indeEtructible, and almost never malfunctions. Sample locations are shown in Fig. 2, p. 000. There are five traverses normal to shore; from west to east they are: traverse A (off Cedar Cut which is no longer in existence but is indicated on hydrographic charts), traverse B (off the San Bernard River), traverse C (off the mouth of the Brazos River), traverse D (off Freeport Harbor), and traverse E (off Oyster Cut, also no longer in existence). Sample stations were determined by observation nearshore and by dead reckoning offshore, specifically, by compass bearing and boat speed after making necessary allowances for drift. This method proved entirely satisfactory as indicated by very close agreement of the bottom profiles with hydrographic charts. The pattern of widely spaced traverses of closely spaced sample stations ( 1 mile apart) provides for detailed profiles while at the same time establishing a grid pattern for spatial control of the entire area. Shallow Marine Sediments Offshore from the Brazos River, Texas LABORATORY TECHNIQUES Size Analysis. Size analysis was done following the hydrometer method utilizing the theoretical approach developed by Day (1950, 1953, 1956) in which the effective depth of an observed hydrometer (density) reading is calculated for the non-uniform sus­pension displaced by the hydrometer bulb. Values of effective depth calculated for the standard hydrometer 152H appear in ASTM tables for 1955. Procedure employed in analyzing samples for this report was as follows: Approximately 20 gram aliquots of raw sample were wet sieved through a U. S. No. 325 mesh screen, the coarse fraction washed to remove salt, dried, and sieved on the Ro-Tap for 15 minutes using a nest of screens employing a quarter phi interval. Visual estimations of shell and aggregates were made under a binocular microscope and subtracted from the measured weights (a necessary step in the interest of accuracy). All weighings were done on an analytical balance; fractions less than 1 gram being weighed to the nearest 0.01 grams. This order of precision is necessary when the cumulative curves are subsequently plotted on prob­ability paper, which greatly expands the extremes. The fine material washed through the wet sieve was retained, 2.55 grams of "Calgon" (sodium hexametaphosphate) added as dispersant, the mixture dispersed for 5 minutes in a malted milk mixer, and the sample plus enough water to make 1000 ml placed in a 1000 ml soil hydrometer jar. Sixteen hydrometer jars were lined up for hydrometer analyses to be run simultaneously. Hydrometer readings were made at 1, 2, 4, 8, 15, and 30 minutes, and at 1, 2, 4, 7, 16, 24, and 48 hours, these times representing half phi intervals in the size distribution. Data obtained from the sieving and hydrometer analyses are used to plot cumulative curves on arithmetic probability paper after the particle sizes have been converted to phi units. Statistical parameters are then calculated employing graphic values read from the cumulative curves. Heavy Mineral Analysis. Aliquots for heavy mineral analysis were taken in such a quantity as to provide 20 to 30 grams of coarse material for subsequent bromoform separation. For some samples containing only a small percentage of coarse sizes, the aliquot was necessarily quite large. Clay was decanted from the raw sample, care being taken not to decant off any of the silt, as it was desired to obtain all of the heavies con­tained in the sample, not just those of a particular size grade. (The choice of which size grade to use in view of the large standard deviation of many of the sediments would be both difficult and questionable.) After oven drying of the coarse fraction, it was placed in a separatory funnel filled with bromoform, the heavy material (sp. gr. > 2.87) withdrawn, weighed, and reduced by means of an Otto Microsplit to a quantity suitable for mounting in Canada Balsam. The light fraction also was weighed. Counts of 100 grains each for each slide were made subsequent to cruising the entire slide for determination of all the mineral types present. Neglecting mineral occurrences of low frequency·, a count of 100 grains provides an ample degree of accuracy. Clay Mineral Analysis. For clay mineral analysis approximately 10 grams of raw sample were placed in a beaker and treated with 36 per cent H20 2 until all activity ceased, which generally required several additions of the reagent. After oxidation, the samples were washed by decantation with distilled water until the suspension remained long enough to withdraw a minus 2 micron fraction, which in turn was used to sediment a glass slide (Grim, 1934). The oriented aggregate sample thus obtained was then analyzed on a General Electric XRD-3 X-ray diffraction unit employing a goniometer speed of 2° 2() per minute. Spectrometer traces were recorded on a logarithmic scale, and direct measurements of intensity (peak heights) were made from the trace after a suitable imaginary base line had been drawn. Three slides of each sample were made--) scale of Krumbein ( 1934) is employed throughout to facilitate calculations and also as a matter of common usage; its relation to other measures is indicated in Table 3. Most of the samples analyzed for this report contained clay in varying amounts, many in such large amounts that the 95 percentile, and not infrequently the 84 per­centile, were beyond the practical limits of size analysis; therefore, the extrapolation method of Folk and Ward (1957, footnote p. 13) was employed. This practice consists of extrapolating lineally from the last measured point (approximately lOcf>) to 100 per cent at 14cf>, and plotting these extrapolated values on the cumulative curve. A sound basis for this practice may be found in electron microscope photographs of clays (Ref­ 330 Shallow Marine Sediments Offshore from the Brazos River, Texas erence Clay Minerals, 1951, p. 129), which show a majority of clay flakes to have an average size of approximately 12. TABLE 3 Relationship of grain size scales for sediments Millimeters Microns Phi (cf>) Wentworth size cla!16 1.00 0.0 0.34 0.25 0.71 0.5 Coarse sand 0.59 0.75 o.5,,,_______500>-----­ --1. 0.42 420 1.25 0.35 350 1.5 :Medium sand 0.30 300 1.75 0.2 25{}<-------2. 0.210 ·210 2.25 0.177 177 2.5 Fine sand 0.149 149 2.75 0.12 12:>--------3. 0:105 105 3.25 0.088 88 3.5 Very fine sand 0.074 74 3.75 0.0625 62.5-----4. 0.053 53 4.25 0.0441 44 4.5 Coarse silt 0.037 37 4.75 0.031 31------5. 0.0156 15.6 6.0 Medium silt 0.0078 7.8 7.0 Fine silt 0.0039 3.9 _ _ ___ _,, Very fine silt 0.0020 2.0 9.0 0.00098 0.98 10.0 Clay 0.00049 0.49 11.0 0.00024 0.24 1'2.0 0.00012 0.12 13.0 Colloid 0.00006 0.06 14.0 Results and Discussion TEXTURAL DISTRIBUTION AND GRAIN SIZE PROPERTIES The neritic zone of marine deposition affords an excellent opportunity to study the interaction of source area and depositional environment as recorded in the texture of the sediments being deposited. Regardless of the original modality of material being supplied to this area by terrestrial agency it is believed that marine distributive forces tend to impart a modal distribution unique to the environment. This condition necessarily results from the features of hydraulic transport-more specifically, division of the load into a finer fraction carried in suspension and a coarser fraction moved by traction ("bed load" in lluvial terminology), the specific division being characteristic of the transport­ing energy of the waves at a particular point. Coarse material moving onshore by traction (essentially) creates a progression of single modes of decreasing medium size in the offshore direction. Super-imposed on this situation is the deposition of a fine mode from suspension with the net result being a bimodal sediment. Additional complexities in the final textural distribution of the sediments are introduced by intermediate means of transport, such as saltation, and sometimes by extreme fluctuations in both the intensity and nature of the transporting agents. Source area will, of course, he representative of the aggregate modal frequency of the entire area of deposition, but its only local influ­ence in the neritic zone will be to control the abundance of individual modes as they occur in the final depositional pattern. The analysis in terms of modal interaction set forth by Folk and Ward (1957) has largely remedied the previously speculative inter· pretation of sediments laid down under these conditions. Distribution. A triangular classification employing sand, silt, and clay as poles pro· vides a convenient means of indicating gross textures of the sediments analyzed for this report (Fig. 17). It may be noted that silt is present only in minor amounts with the exception of a small area near the mouth of the Brazos and in the very nearshore zone immediately to the west. The absence of material in the study area in the size range 6-104> is patent from a consideration of Fig. 18, which is a frequency curve plotted on the basis of all of the samples analyzed. This curve signifies that the source area is not supplying much medium and fine silt. and further presents the possibility that a uni­versal deficiency of fine or medium silt may exist because the Brazos drains a large and diverse terrain. Future observations on this point certainly are indicated. Pure clays are absent from the distribution, 83 being the highest percentage obtained in the sample suite, but pure sands do occur on the beaches. The textures represented on the triangular diagram (Fig. 17) and the modal frequencies shown on Fig. 18 set up the limits within which the following discussion of sedimentary parameters must necessarily be bounded -afact which should be constantly borne in mind. A textural nomenclature employing the same sand-silt-clay triangular scheme (Folk, 1954, p. 349) is illustrated in Figure 19. The distribution of sediment types in the study area based on this nomenclature is shown in Figure 20. At first glance a certain amount of abrupt change between sediment types seems to prevail-this results from the gross nature of the classification and is not entirely indicative of the actual textural order attained by the sediments. Sand-silt-clay ratio is not refined enough to indicate the finer details of sedimentary distribution. In the discussion of the spatial aspects of the statistical parameters which follows later, this fact will be appreciated more fully. An essentially uniform progression of sediment types extends from the well sorted unimodal fine sand and coarse silt of the beach to the predominantly clayey sediment at a depth of 50-60 feet just shoreward of the shoal area, at which point the trend re­ Ftc. 18. Frequency distribution of size grades for all samples. .• ·::. ••SIU Fie;. 19. Textural nomenclature triangle. Adapted from Folk (1954) . verses and the sediment once again becomes coarser. The cause of this reversal is the presence of the submerged deltaic plain (the entire area seaward of the 60 foot depth contour) discussed at some length previously. Within the plain itself, a tongue of very fine sandy mud extends from. the west in 10-90 feet of water into the main region of muddy very fine sand surrounding it. The uniform progression of sediment types referred to above is the result of a de· crease in modal size offshore from the beach. These modes comprise the "coarse" frac­tion referred to in the following sections and range from fine sand through coarse silt. The offshore topographic highs also supply a coarse mode in the sand size range. The "fine" mode referred to in following sections is a poorly sorted clay mode included be­tween 10 and l4. A band of silt adjacent to the mouth of the Brazos and extending west parallel to shore is the result of deposition of Brazos material, and represents a smooth transition from very fine sand through coarse silt to medium silt, at which size a definite break in properties occurs. Distribution of the sediment about the modern delta follows a similar pattern to that described by Scruton (1955) and Shepard (1956) for the eastern Mississippi delta. Classical topset beds, represented by the subaerial portion of the delta surrounding the mouth of the Brazos, consist largely of fine material carried into lagoons by tides and storm waves (cf. previous section entitled Subaerial Delta). Borings from the delta (Odum, 1953a, p. 89-96) show coarse reworked material interlayered with fine ma­terial causing rather poor sorting. Sand, sandy silt, and silt zones grade seaward into an area of mud deposition, exhibiting a characteristic decrease in grain size into deeper water as well as in a lateral direction away from the delta proper. This sequence of sedi­ment may be compared to the so-called "foreset" beds of the literature, but the dips of the beds in the study area are much less ( 1-2°). Slopes of this order are typical of most modern deltas (Shepard, 1956, p. 2615-2620). A clay belt 7-8 miles offshore from the subaerial delta in 60 feet of water is related, as a general rule, to delta formation. According to Shepard (1956, p. 2559-2560) clay zones are related to river mouths in the Mississippi River delta: "Off all the passes there appears to be a consistent 50-70 per cent clay zone found within a few miles of the river mouths and forming a band around the distributaries." Scruton ( 1955) referred to the same zones as "offshore clays." Maximum deposition of clay from the suspension . •. Frc. 20. Distribution of sediment types. load of the river accounts for this clay accumulation. No relation exists between these clay belts and depth, their distribution with respect to the mouth of the river is more lateral than vertical. Still farther seaward an abrupt coarsening to a zone of sand and muddy sand mar­ginal to the clay belt occurs. Its fine material (fine silt and clay) is being deposited out of suspension from material supplied by the Brazos River, while the sand size material is probably derived from older sand of the submerged deltaic plain; that is, from the topographic highs caused by the outcrops of late Pleistocene sand. It is less likely, but nonetheless possible, that these outcrops are remnants of buried beach ridge, offshore bars, or possibly even reefs. A unique condition of double source area is thus imposed on the sediments of this region, and it was from this line of reasoning that the true re­lations presented by the contour map of kurtosis was revealed. What the map really indicates is the trimodal tendency of the sediment. The relative progression of mode size toward the offshore sand outcrops substantiates this interpretation. Sample A-10 (clay) has a subordinate sand mode at 3.25, A-11 (muddy sand) has a sand mode at 2.75, while on top of the high A-12 (sand) has a single mode at 2.70. Relatively minor deposition of fine material over the large region seaward from the clay zone would constitute the "bottomset" beds needed to complete the classical pat­tern of deltaic deposition for the study area. As no cores were taken, direct evidence is 334 Shallow Marine Sediments Offshore from the Brazos River, Texas lacking that such a deposition of fine material is actually taking place. Paleontological and clay mineral composition data, however, indicate that deposition of clay is occurring in this area, at least in the region 10-20 miles offshore. Fluctuations in the sediment distribution in the far offshore portion of the study area are the result of selective patterns of winnowing and sand deposition. Abnormal agents, e.g., hurricanes that operate in this region could account for the movement of large fiIUantities of material, which would not subsequently be subject to modification by normal agents. Properties. Consideration of the textural properties by means of their statistical para­meters will be enhanced by noting the modal character of the shallow marine sediments as indicated by their size distributions. Typical cumulative curves plotted on probability paper with their respective frequency curves are illustrated in Figure 21. Oyster cut is a very well sorted, nearly symmetrical, mesokurtic, unimodal sediment typical of the beach sand. Sample B-7 represents an almost unimodal clay distribution (100 per cent clay distributions are not present in the suite of samples from the study area). It is very poorly sorted and very negative­to negative-skewed, which would be anticipated from a predominant clay mode because of the physical properties of clay, and is mesokurtic despite its being coarsely skewed because of its very poor sorting. In D-7 a subequal mixture of the two modes results in a very poorly sorted, positive-skewed, very platykurtic size distribution. The clay mode in this sample is rather well developed. The modal character of sediments in the study area may be reviewed in the following manner: 1. A "coarse" mode is represented by a well sorted mode in the fine sand to medium silt range, the particular size of the mode being determined by its position in the wave energy spectrum. 2. A "fine" mode consisting of a poorly sorted range of material in the clay size range. In a few sediments two modes are distinguishable within this range, resulting in trimodality of the particular sediments. A 100 per cent fine mode is not represented as such by any of the sediments in the study area. 3. These two principal modes may occur independently or may be mixed in any . proportions. Figures 22, 23, 24, 25, and 26 are profiles of the four grain size parameters plotted versus sample location (distance) . For each traverse the depth profile is also indicated. These profiles should be referred to in the subsequent discussion. Mean Size.-Values of mean size range between 2.3 and 10.5, clustering in the region of 5 to 7. This cluster of mean sizes approximately midway between the two main modes represents mixing of subequal portions of the modes (chiefly in the muddy sand and sandy mud zones offshore) and not an actual predominance of material of this particular size range in the sediment. Because of the scarcity of fine silt in this environment none of the samples analyzed had a primary mode in this region (as indicated by the sorting rnlues--an interrelationship to be discussed in detail in a later section) . A significant feature of the mean size-slope relationship is the dependence of slope on the grain size of the sediment supplied to the slope. This is emphasized in Traverse B, where an abundance of silt size material has caused the slope to adjust in such a manner as to accommodate that particular grain size. Bascom (1951, p. 874) has also Frc. 21. Typical cumulative curves and their respective frequency distributions for sediment in the area of investigation. noted this dependence of beach face slope on median diameter of the sand, and the long range effects of changing sand supply (or rather, changing grain size distribution) on the breach slope has been noted at Oceanside, California (Wiegel, Patrick, and Kim­berley, 1954, p. 895). A marked relationship of grain size with depth is at once apparent from an examina­tion of the respective profiles. A bivariant plot of these parameters (Fig. 27), in which samples from the nearshore zone are designated by an x and those from the submerged deltaic plain by a circle, illustrates a number of interesting features. First, mean size and depth are obviously closely interrelated in the nearshore zone, decreasing regularly from an average of 2.8 on the beach to over lO at a depth of 60 feet in the clay belt. Scatter around the indicated trend is the result of inequalities in grain size of ma­terial being supplied to the various localities. This conclusion naturally follows from the observation made in the preceding paragraph that slope is a function both of specific wave energy and mean size, and that, therefore, a particular locale will accommodate any relative spread of grain size being supplied to it by adjusting its slope. With this fact in mind it is not difficult to visualize the difficulty in attempting to carry a par­ticular depth-mean size trend common to one area into another area where different local conditions of supply prevail. This weakness actually suggests a possible value of mean size-depth plots in respect to comparing various locales with regard to source area. If the respective trends were similar a common source would be indicated, but if the trends were quite different distinct source areas would be indicated (all the foregoing dependent on similar wave conditions). Second, Figure 27 shows a break in steepness of the trend to occur at approximately 25-30 feet. The previously mentioned observation of Dietz and Menard (1951) to the 336 Shallow Marine Sediments Offshore from the Brazos River, Texas ~~,,~-,"--·"--·, .~.-.L.-ZLO ZLZl""'-­ .~~~~~~,'--,"--,"--L.. "--."--·"--,~-O-ZL-Z ...::J:Z< Somplt LOCOllOll 10 II ll l} " Somp lt Loco t1o n 10 II ll 13 I~ Sompl t Loccil 1on 10 JI 12 IS " Sompl t lotolion " Sompl t Locollon FIG. 22. Profiles of depth, mean size, sorting, skewness, and kurtosis for Traverse A. effect that maximum erosion probably takes place at 25-30 feet also should be recalled. This feature might be a significant point to establish in analyzing ancient sediments with respect to determining direction to the paleoshoreline. Third, the cluster of points about 6cf> in depth below 60 feet indicate the bimodal mix­ture of subequal sand and mud in the region seaward of the 60-foot depth-contour, and ~ ..~___,.,,,:::::.::::::=========-­ FIG. 23. Profiles of depth, mean size, sorting, skewness, and kurtosis for Traverse B. a slight trend toward increased coarseness of the sediments offshore also seems to be indicated. This grouping of points serves both as evidence for the presence of an older deposit (the submerged deltaic plain) being reworked and for the deposition in this region of fine material from the Brazos with coarse material being brought in from another source. Another interesting feature of this variance of mean size with depth is that in the close inshore zone of steepest slope and highest wave energy the sediment is unimodal (or at worst has a very predominant coarse mode), the modes decreasing in size offshore. The progression of coarse modes extends through the silt size range, but modes this fine are secondary, i.e., they make up only a minor portion of the sediment. Note is once again made of the deficiency of this size material in the entire sample suite. Medium and fine So11pl1 LocallOft . So111pl 1 Locolion Fie. 24. Profiles of depth, mean size, sorting, skewness, and kurtosis for Traverse C. silt approach the lower limits of applicability of the laws of hydraulics and a certain amount of diffuseness might therefore be anticipated in their size distribution for this reason. It may be concluded, then, that sorting in this region is segregating specific modes irrespective of any original modes the sediment may have inherited from the source area. The source area will, however, dictate the abundance or, for that matter, the l l 4 ' ' 1 • ' 10 So111 ple Locohon ,;;= • i. .. -0. l 1 I t 10 II Sampl1 Locol1on Samplt local1on Sampl t Locorion FIG. 25. Profiles of depth, mean size, sorting, skewness, and kurtosis for Traverse D. occurrence of any particular mode. (Proof of this statement is the abovementioned pro· gression of modes offshore.) Topography is clearly reflected by mean size which outlines the sand outcrops and shows a consistent decrease offshore (to 60 feet) ; nevertheless, it is a moot question as to which parameter is independently and which dependently variable. The fact that Frc. 26. Profiles of depth, mean size, sorting, skewness, and kurtosis for Trawrse E. the elevations occur at approximately 60 feet, which is the depth generally taken to be the lower limit of effective wave action, is probably significant. In Traverse E only a slight increase in elevation in the vicinity of stations 13-18 is related to a marked increase in mean size. Standard Deviation.-The relationship between sorting and mean size mentioned above also apply to the plot of standard deviation. Best sorting occurs in the beach and nearshore region, with relatively good sorting on the topographic highs, particularly at station A-12. Values of standard deviation ranged from 0.25 at E-1 to 3.96 at D-7. A general trend toward improved sorting values (relative to the adjacent sorting values) in the vicinity of the clay belt is caused by the predominance in this region of the nearly pure clay mode (cf. particularly Traverse A (Fig. 22) and Traverse B MEAN SIZE It) Frc. 27. Scatterplot of mean size and depth. (Fig. 23). Poorer sorting (higher standard deviation values) exists in the intermediate area between the beach and the clay zone as a result of mixing of the two main modes. Proof of the statement made by Ippen and Eagleson (1955, p. 77-88) concerning the mixing of various size grades at any break in bottom slope is obtained by comparing the profiles of depth and standard deviation. At each change in slope on the depth profile a corresponding abrupt increase in values of standard deviation occurs, indicating vny poor sorting due to a more or less heterogeneous mixture of size grades. High values of standard deviation (poor sorting) evident in the region of the sub­merged deltaic plain indicate that this area is functioning passively in respect to sedi­ment transport. A predominance of mean size values in the range of a rather coarse mode would be expected to occur with a lower range of standard deviation value than actually· are present. The conclusion can be drawn, then, that in depths of water greater than approximately 60 feet (the minimum depth of water over the region of the deltaic plain) fine material derived from areas onshore of the 60-foot depth-contour is quietly being deposited in this deeper water. Turbulence caused by waves is insufficient at these depths to lift the bottom sediment and place it in motion or even to keep the suspended load arriving in this region from settling out. Poor sorting in depths greater than 60 feet may be interpreted as placing a lower limit on the effectiveness of sorting action in the neritic environment. Beyond this point the sediments can be expected to become pro­gressively finer grained and sorting becomes a function entirely of the depositing medium-no redistribution occurring after the suspended material has been deposited. Skewness.-Skewness is a very effective indicator of the modal nature of sediment. Well developed unimodal distributions are symmetrical, as are equal mixtures of two modes, while mixtures of two modes in very subequal amounts cause extreme values of skewness. Depending upon which mode is dominant, coarse or fine, skewness values will be positive or negative, respectively. Traverse A (Fig. 22) is an excellent example of skewness as a function of bimodality. The well developed unimodal beach sample ex­hibits near symmetry, but as distance offshore increases the sediment becomes pro­gressively finer and finer {more positively) skewed to a point where the addition of the finer mode is in a large enough quantity to effect the spread of the central portion of the curve as well as the tails, and skewness values decrease. When the modes are mixed Shallow Marine Sediments Offshore from the Brazos River, Texas in equal amounts (in the region of sample A-5) a symmetrical condition arises and in the region farther offshore skewness becomes progressively more negative. A return to symmetrical values in the proximity of A-10 indicates mixing of the two modes in equal amounts once again, rather than a return to a perfectly unimodal sediment, as a pure clay (fine mode) is not present. The bulk of the zone offshore from the 60-foot depth­contour has strong positive skewness because of the dominance of the coarser mode. For the study area skewness ranged from -0.35 to +0.88, with a predominance of positive-skewed values. The significance of the fact that a majority of the samples were positive-skewed is that the sample suite nearshore represents a shallow neritic environ­ment with the coarse mode still dominant. If sampling had been carried out to greater depths, where the clay (fine) mode predominated, negative-skewed values would be the order of the day. With no great stretch of the imagination one can envision a fre­quency plot of skewness values serving to indicate direction from the shoreline-an increase in positive-skewness values showing progressive nearness to the shoreline, while an increase in negative-skewness values would indicate an offshore direction. Sharp peaks of positive-skewness effectively mark the edges of the topographic highs. Kurtosis.-Like skewness, kurtosis is an effective indicator of the modal relationships of a sediment. Values of kurtosis range from 0.53 to 9.37 for the study area, inclusive of a fairly uniform spread of platykurtic and leptokurtic values. The uniform progression of modal additions noted on Traverse A (Fig. 22) in the previous discussion of skewness is also indicated in an obvious fashion by the profile of kurtosis values. The nearly unimodal (but not perfectly unimodal) samples are ex­cessively peaked (leptokurtic), while the intermediate samples representing subequal proportions of the two modes become progressively mesokurtic, and those sediments with equal amounts of the modes are deficiently peaked (platykurtic). The non-normal nature of kurtosis is illustrated in Figure 21. From the frequency curve it will be noted that in sample A-2 the addition of a small proportion of the fine mode ( > 15-20% ) causes extreme leptokurtosis. The addition of slightly more of the fine mode (20-30% ) produces mesokurtosis as indicated in sample D-29. Subequal or equal amounts (30-709(-) of both of the modes cause platykurtosis, as on Sample D-7. Thus, from the range of relative values of kurtosis for a given sample suite one might predict the relatiYe proportions of the modes contained in a particular sample. Traverse C (Fig. 24) presents an interesting situation. The kurtosis and depth pro­files are almost identical. The latter feature points up the high degree of interrelation between not only kurtosis but all of the statistical parameters with each other and with their environment as represented by the depth profile. The fact that all of the samples in this traverse, which is off the mouth of the Brazos, are deficiently peaked indicates that the river is depositing coarse material faster than marine forces can redistribute it. The progressive sorting action of the neritic environment does not have the opportunity to rework the sediment with the net result being a poorly sorted sediment with a wide separation of modes occurring in subequal to equal amounts. Further detailed discussions of the four statistical parameters follow in the next sections. SPATIAL RELATIONSHIPS OF GRAIN SIZE PROPERTIES Having presented the significance of the several grain size parameters in profile, we may now proceed to the spatial aspects. Recent papers on spatial distributions are almost entirely lacking with a few notable exceptions (Krumbein and Aberdeen, 1937; Inman and Chamberlain, 1955; Trask, 1955; and Shepard, 1956). The writer knows of no papers in which skewness and kurtosis have been individually treated. Mean Size. Contours of mean size (Fig. 28) conform with topographic contours off­shore to the limit of effective sorting by wave action. Beyond this point the alongshore configuration is hardly patent, the change indicating that a different set of agents pre­dominate. The geologic history of the study area beyond the 60-foot depth-contour, as recorded in sedimentary properties retained from an earlier period of deposition, may explain the present lack of alongshore conformity. If normal nearshore agents were operative in this depth of water (> 60 feet) an inherited configuration might be de­stroyed and subsequently replaced by one more compatible. Storm waves may be in large part responsible for the grain size distribution in this deeper zone inasmuch as normal wave action cannot operate at these depths to erase the effects of the occasional storm waves. Another agent that may influence the mean size pattern in deep water is bottom current for which we do not yet know the mechanics. The transport of heavy minerals from the Mississippi River out to a depth of at least 200 feet, mentioned by Shepard (1956, p. 2598), suggests that deep-water bottom currents may be rather competent. Also, the presence of the submerged deltaic plain must partly (or maybe dominantly) influence the distribution of mean size in the portion of the study area that it occupies. Topographic highs are precisely reflected by mean size, as would be anticipated. The closed lOcp contour approximately 7-8 miles offshore accurately delineates the relation­ship of the so-called "clay belt" to the mouth of the Brazos River. Standard Deviation. Sorting and mean size are so interdependent that the trends of mean size (Fig. 28) are also reflected in contours of standard deviation (Fig. 29). Progressively poorer sorting occurs offshore to a maximum midway between the loca­tions of the two main modes, the beach and the clay belt respectively. The poor sorting of the clay mode is so dominant that the bimodality of the sediments is partly obscured, indicating the necessity of employing jointly all of the statistical parameters in order to accurately interpret the sediment. Once again, the topographic highs are clearly outlined. A wedge of improved sorting extending into the area from the northeast illustrates the effectiveness of the winnowing process on even very minor elevations (in the range of 2-4 feet of relief). Contours of mean size did not reflect this particular topographic anomaly. The existence of relatively poorer sorting closer to shore in the northeastern portion of the study area probably is due to a local reduction in wave energy caused by the minor elevation offshore from the anomalous zone. Skewness. Contours of skewness (Fig. 30) effectively illustrate the modal nature of the sediment in an orientation parallel to shore. The fine mode, which was almost obscured on the map of standard deviation, is clearly indicated by negative-skewness values. Also, the modal characteristics of the sediment onshore from the 60-foot depth­ 344 Shallow Marine Sediments Offshore from the Brazos River, Texas FrG. 28. Contour map of mean size. contour, which were completely obscured by poor sorting, are shown in detail by the skewness contours. Topographic features are reflected only to a very minor extent (in comparison to mean size and sorting) by skewness values, indicating again that the various para­meters must be used in conjunction with one another. The change in grain size repre­sented by the 7cp contour on the mean size map is also reflected by a trend toward more symmetrical skewness relative to the adjacent sediment. Kurtosis. An entirely different pattern is presented by the map of kurtosis (Fig. 31), showing more similarity with the plot of standard deviation than with any of the other parameters. At first glance the modal character of the sediment as defined by kurtosis is quite different from that as defined by skewness. The apparent conflict is due to the extreme sensitivity· of the kurtosis measure. Although, as has been mentioned previously, the pure clay mode is not present in the sample suite of the study area, its presence is clearly indicated by the platykurtic area contained within the 0.400 K ~contours. Specifically proceeding seaward from the beach, where mesokurtic values signify a well developed unimodal sediment, extreme leptokurtosis is encountered, representing additions of a secondary clay mode in amounts less than 15-20 per cent. Farther off­shore kurtosis values decrease, indicating progressively larger additions of the fine mode until platykurtic values occur, signifying approximately subequal amounts of the two Shallow Marine Sediments Offshore from the Brazos River, Texas u•tt• ... . Fie. 29. Contour map of standard deviation (sorting). modes. Still farther offshore an exactly reversed condition prevails until on top of the topographic high an essentially pure coarse mode is once again encountered. The closest approach to the pure clay mode is shown by the small 0.475 K~ contour, indicating an approximate 10 per cent addition of the fine mode. Clay is actually present in the amount of 83 per cent, the discrepancy being introduced by the occurrence of a third mode in the range of 7-8.p. These two modes generally are not distinguishable and show up as one poorly sorted fine mode. The fact that kurtosis indicated this tri­modality was not immediately realized, as was indicated in the discussion of the distri­bution of sediment types (p. . ) . Three areas of coarse modes are shown on the map; the beach, the prominently elevated region, and the very minor elevation in the east central portion of the study area. The closed 0.400 K ~contour off Freeport Harbor represents a remnant of the Old Brazos River delta in the nature of a clay belt, which always occurs off the mouths of rivers. Kurtosis and skewness together can yield a complete picture of the modal character­istics of sediment. and an increased usage of kurtosis is certainly indicated. INTERRELATIONSHIP OF GRAIN SIZE PARAMETERS A detailed bivariant analysis of the various grain size parameters is useful in deter­mining the geologic significance of the individual environment. Frequent reference to Shallow Marine Sediments Offshore from the Brazos River, Texas FIG. 30. Contour map of skewness. the contour maps presented in the preceding section will aid materially in visualizing the interrelationships to be indicated by means of the following scatterplots. MEAN SIZE VERSUS STANDARD DEVIATION The relationship of mean size and standard deviation is the best known and most thoroughly studied of all of the grain-size parameters. For the limited range of sizes available in the study area, the scatterplot (Fig. 32) exhibits a marked trend which is related to the particular modal characteristics of the sediment. Beach and very nearshore samples are very well sorted to well sorted and cover a relative! y large range of mean size from 2.3 to 3.Scp. These sediments are the product of the highest sorting attainable in the neritic environment-a fact which accounts for the extended size spread. The efficacy of sorting in this zone is such that regardless of the size of the material supplied, good sorting is imposed. Support of this statement is to be found in the previously mentioned dependence of beach slope to median size. A similar conclusion is drawn by Folk and Ward (1957, p. 18-19) in a theoretical consideration of the bivariant nature of mean size and standard deviation. These beach and very nearshore sediments represent the well developed coarse modes (very fine sands or coarse silts) which are mixed in decreasing proportions with the not so well developed fine (clay) mode to produce the poorly sorted sediment of mean size intermediate between the two main modes. Modal mixtures of roughly equal proportions yield the Frc. 31. Contour map of kurtosis. poorest sorting, as they possess well developed extremes and a poorly developed central portion (cf. Fig. 21, Sample D-7). Generally poor sorting prevalent in the finer grades (clay size range) is a result of the essentially uniform reaction of these sizes to hydraulic action in the form of traction movement or creep. Nevertheless, as suggested by Inman (1949, p. 61-63), when this material is suspended it is sorted by the large differences in settling velocities of the various grain sizes. A trend toward improved sorting is definitely shown on Figure 32 for samples with mean size finer than Sep. Although no pure clay was present in the sample suite, it is assumed that the standard deviation of even a relatively· pure clay would not qualify it to be placed in much more than a poorly sorted classification because it is colloidal and probably is composed of a variety of minerals, and conse­quently its physical properties are variable. Assuming the indicated trend to be sinusoidal, the equation of its curve can be de­termined as a matter of interest. Examination of Figure 32 indicates that for an average maximum standard deviation of 3.9 Vr, average mean size is 7.0ep; and that for an average minimum standard deviation of 0.3 v;:average mean size is 3.0ep. Employing these values and applying the general formula for a sine function y =a sin 8 + b, the specific relation Vr = 1.8 sin 45° (Mz -Sep) + 2.1 '\['; is established. The dashed line of Figure 32 is the curve of this equation. .­ ' D -8uc• ~ z -on ,,_.,,.,,~-',-___.,.,,o~,, ~.,~~., ,,, > ""°~.~,,~~~~~.,~~_.,,.~--',~ 4.0 5.0 6.0 10 8.0 9.0 10.0 11.0 12.0 Meon Siu (M1J Mean S1rt (M, ) Frc. 32. Scatterplot of mean size and standard F1G. 33. Scatterplot of mean size and skewness. deviation. A continuation of this sinusoidal trend into coarser sizes can be observed in grain size studies made by Blatt (1958, p. 74) and Folk and Ward (1957, p. 17). Blatt's curve, representing beach sand and gravel, directly adjoins the curve of this report, while that of Folk and Ward, compiled from analyses of river sand and gravel, has a similar con­figuration but is displaced upward into poorer sorting values. These three studies are directly comparable as they all employed the same statistical measures, namely, those of Folk and Ward (1957). Both from this study and by comparison with the above mentioned work it may be concluded: 1. A distinctive sinusoidal relationship exists between mean size and standard devia­tion which is an accurate measure of the modality of sediments and an effective indicator of environment. 2. The relative position of the curve with respect to sorting distinguishes the littoral environment from the fluvial environment. Mean Size versus Skewness. A sinusoidal trend is apparent in the scatterplot (Fig. 33) of mean size and skewness, but is displaced toward the coarser sizes in comparison to the mean size-standard deviation plot. The high degree of scatter in the near symmetrical zone is caused by the independent nature imparted to mean size by the efficacy of the very nearshore environment. Predominance of extremely positive-skewed samples is a result of sampling only nearshore sediment, with the trend toward negative-skewed sediment farther offshore from the 100-foot depth-contour being clearly predicted. From left to right, the indicated trend passes through nearly symmetrical unimodal samples (relatively size independent) to fine skewed and extremely fine skewed sediment representing mixtures of the two main modes with the coarse mode dominant. Continu­ing around the curve, skewness values decrease to zero for samples containing approxi­mately equal modal proportions, and skewness is negative for the remaining samples, which are composed predominantly of the clay mode with a very small amount of coarser material. If additional samples consisting of 100 per cent clay size material were avail­able for this region, it is assumed that they would cause the trend to reverse once again with the subsequent symmetrical values of skewness indicating a return to a unimodal condition. Additional evidence of the relationship of skewness to mean size may be had by re­ferring back to the contour maps of these two parameters (Figs. 28 and 30). Mean Size versus Kurtosis. The extreme sensitivity of kurtosis to slight additions (2-10% ) of a second mode to a primary mode is strikingly illustrated in the scatterplot of mean size and kurtosis (Fig. 34) . A well developed coarse mode, at approximately 3cf>, quickly passes from a mesokurtic condition into one of extreme leptokurtosis with the addition of about 5 per cent of a secondary mode. Increasing amounts of the fine mode, up to 20-25 per cent, causes a subsequent decrease in leptokurtosis until the fine mode makes up about 25-30 per cent of the sediment, at which point a return to meso­kurtosis occurs. Platykurtosis results when the two main modes are mixed in subequal amounts with maximum platykurtosis prevailing at a 50-50 modal ratio. If the clay mode were present, the curve would extend on up into extreme lepto­kurtosis values and then return to mesokurtosis to complete the entire cycle. The uni­form distribution of values about the curve is probably characteristic of the uniform, gradational energy pattern of the neritic environment-fluvial sediment showing a marked tendency to cluster (Folk and Ward, 1957, p. 20) as a result of a fluctuating energy budget. Scatter in the region coarser than 5cf> is caused by the inconsistency of the size of the coarse mode; it will be recalled that sorting causes a progressive size decrease of the coarse mode in the offshore directio.n. If the coarse mode remained constant, as it would if it were inherited from a particular source area, there would be no scatter and an environment other than neritic would be indicated. Mean size-kurtosis variation therefore has usefulness as an environmental indicator based on the degree of spread (cluster) and on the presence or absence of scatter in the 2-6cf> region. Standard Deviation versus Skewness. The relationship of standard deviation and skew­ness can be established theoretically (Folk and Ward, 1957, p. 20) as being a circular trend; unimodal samples with good sorting and equal mixtures of two modes with the poorest possible sorting both will yield symmetrical skewness values, whereas 75 :25 mixtures of the two modes will yield the most nonsymmetrical skewness values. The top half of the trend is exhibited fairly well (Fig. 35 ), with a clustering of samples having a coarse to fine mode ratio of 3 to 1 in the region of very poor sorting and positive skewness. The significance of the relationship between skewness and sorting was indicated by the discovery that kurtosis indicated trimodality. Mixtures of two well developed modes will result in sediments which fall on the circular trend, but mixtures of one well de­veloped mode and one poorly sorted mode result in sediments which depart from the curve. From Figure 35 it will be noted that the unimodal beach sediment is symmetrically skewed and possesses uniformly good sorting. Progressing in a clockwise direction around the trend, additions of the poorly sorted secondary mode (which actually is a mixture of two lesser modes) causes departure from the ideal circular trend. Increased 350 Shallow Marine Sediments Offshore from the Brazos River, Texas L[GOO • 1 ......... _.1/ d 0 . ' - .,... l 0·30~io--:!:,,:--,.o----,.o --;;1.0·"'°1o"'n--,!-,,---,!o i.o:---t;;-;:s"'°,,,..--,t,,.---•"'•----,•o-oJ11.o12. Mean Sia (M, ) Stondord Otv1ohOl'I (Vil FIG. 34. Scatterplot of mean size and trans· FIG. 35. Scatterplot of standard deviation and formed kurtosis. skewness. departure results with increasing additions of the poorly developed fine mode, reaching an extreme when the fine mode predominates, as is indicated by the randomness of the negative skewed samples. Because of the inherent poor sorting of clay the indicated trend does not return to low values of standard deviation, but rather terminates at a higher value of standard deviation which represents the maximum sorting obtainable by 100 per cent clay. Bivariant plots of skewness and standard deviation have now been established as possessing usefulness in determining the relative degree of development of modes and in ascertaining the polymodal nature of sediment. Standard Deviation versus Kurtosis. The relationship between sorting and kurtosis is shown in Figure 36. Once again, poor sorting of the fine mode accounts for the scatter in the platykurtic samples. Starting with the unimodal beach samples possessing good sorting and normal kurtosis, a slight addition of clay causes extreme leptokurtosis, reaching a peak at 1.5 YI· Increased additions of the fine mode up to 20-30 per cent, cause a return to mesokurtosis and a shift to poorer sorting. Mixtures of approximately equal amounts of the two modes cause platykurtosis and poorest sorting. Further addi­tions of the fine mode in excess of 50 per cent cause the trend to reverse and to terminate in a region of slightly better sorting and mesokurtosis. Two groups of sorting values are easily noted, either the sediments are very well sorted and unimodal or they are poorly sorted and polymodal. Skewness versus Kurtosis. A number of interesting relations appear on the plot of skewness versus kurtosis (Fig. 37) . First is the lack of samples with normal skewness and kurtosis, with only the unimodal beach samples falling into this category. Second, although symmetrically skewed very platykurtic samples are relatively abundant, there are no symmetrically skewed extremely leptokurtic samples. As Folk and Ward (1957, p. 21) explain, in order for an extremely leptokurtic sediment to be symmetrically FIG. 36. Scatterplot of standard deviation and FIG. 37. Scatterplot of skewness and trans-transformed kurtosis. formed kurtosis. skewed it would have to have both a coarse and a fine tail in exactly equal amounts; in other words, a trimodal sediment with a very pronounced middle mode. No such samples were present in the study area. The significant feature of this plot is the well developed trend with only two or three samples departing at all from the trend. The reason for this is that skewness and kur­tosis are related in such a manner that they react similarly to sorting and, therefore, when they are plotted against one another the effect of sorting cancels out. This is fortunate, as it permits examination of sediment with poorly developed modes, so as to determine the modality independently of the obscuring effect of sorting. The trend (Fig. 37) represents the following sediment variation: Unimodal samples, at A, exhibit normal kurtosis and are symmetrical. Slight additions of a second mode cause extreme leptokurtosis and positive-skewness, B; additions in excess of 5-7 per cent and less than 20 per cent cause the sediment to remain positive-skewed, but to return to a mesokurtic condition. Increasing amounts of the fine mode make the sediment platykurtic (but still positive-skewed), and at C a change in direction occurs where the samples remain platykurtic and become progressively more symmetrical, normal sym· metry being acquired when the modes are present in equal amount. The curve stops at D for the suite of samples from the study area because of the poor development of the clay mode. (If the clay mode were well developed the remainder of the cycle would be similar and opposite to the half just described.) Four-dimensional Relationship. Folk and Ward (1957), in a gravel-sand bar on the Brazos River, have accurately plotted a helix illustrating the interrelationships of all four of the grain size parameters to each other in one plot. The sediments examined in this report extend their four-dimensional plot into the region of finer sizes and indicate the validity of such a helical model in the sand to clay size range also. In the writer's opinion, careful analysis of bivariant plots and, in par­ticular, contour maps of the individual parameters, offers the most fruitful field for determining the environment and predicting directional trends of ancient sediments. MINERALOGY Mineralogy of the coarse fraction ( > 4.5) only will be discussed in this section, clay mineralogy being reserved for later independent treatment. Light Mineral,s. Canada Balsam mounts of the light minerals were made for all the samples subsequently examined for heavy mineral content. The light fraction is rather uniform within the study area and consists predominantly of subangular quartz, with some feldspar (probably derived from the Colorado River drainage area or, in a remote sense, from the crystalline rocks of northeastern New Mexico) and variable amounts of organic material. Mineralogically, the offshore sediment is classified as subarkose, con· taining 15-25 per cent feldspar and 75-85 per cent quartz. Beach samples are pre­dominantly quartzose, containing more than 95 per cent quartz, and compositionally fall in the orthoquartzite clan (Folk, 1954). Metamorphic rock fragments were not detected in any of the sediments. Glauconite occurs throughout the study area with the exception of the beach and surf zone. Most of it is fresh, frequently showing striations; generally it has a larger grade size than the terrigenous minerals-both characteristics indicating formation in place, with no, or very little, subsequent transportation. Material in the study area always occurred as well rounded pellets. Glauconite, although common and persistent, comprised less than one per cent of the sediment and therefore was not included in the mineral counts. Shell Fragments. Shell fragments are not plentiful in the study area except in samples of sediment from the topographic highs, where they constitute about 50 per cent of the sample, the other 50 per cent being sand. All other samples contain less than 2-3 per cent shell, which comprises the coarsest size grade of the sediment. Pelecypod fragments make up the bulk of shell material ; much smaller amounts of echinoid spines and a few ostracod valves making up the remainder of the shell. The presence of echinoid spines in almost all the samples seems to confirm the conclusion drawn by Shepard and Moore ( 1955, Fig. 28) that echinoid spines are characteristic of the open Gulf. Heavy Minerals. Heavy mineral distribution is a powerful tool for the three-dimen· sional interpretation of a sedimentary body. In this study sorting factors have been judged to exhibit a minor influence, permitting the determined heavy mineral suite to be analyzed in terms of source areas. Figure 38 illustrates the relative abundance of heavy minerals in respect to the coarse decant cut of each sample. The areas of the circles are directly proportional to numerical values of percentage by weight, which are also indicated. Slightly higher percentages are obtained in most of the eastern part of the area, indicating a "dilution" of the central and western parts resulting from a paucity of heavy minerals currently being contributed by the Brazos. The present siltload of the Brazos River is derived primarily by erosion of the predominantly second cycle Cenozoic sedimentary rocks of the Coastal Plain, bank erosion between Waco and the Gulf accounting for essentially the entire siltload of the Brazos. Any of the less stable minerals which have not already been removed from the mineral suite of these sedimentary rocks may not exist after outcrop weather· ing and subsequent transportation down the Brazos. However, the Beaumont clay is unique. It possesses an abundance of hornblende derived from erosion of the Central Mineral Region during the Pleistocene Epoch. The hornblende is carried only a short Fie. 38. Distribution of heavy mineral fraction relative to gross decant cut. Numbers represent percentage by weight. distance to the Gulf, so that a small percentage of relatively unstable minerals are actu­ally included in the Brazos suite. Local variations, probably caused by small scale patterns and the sampling procedure, were observed in the percentages by weight of heavy minerals in the nearshore zone where offshore bars were developed. If a sample were taken from a ripple ridge it would contain almost no heavy minerals, but if it were obtained from the adjacent ripple trough it would contain an abnormally high percentage of heavy minerals. In the study area the most abundant heavy minerals are hornblende, zircon, epidote, garnet, tourmaline, rutile, and apatite; basaltic hornblende, clinozoisite, enstatite, mona· zite, staurolite, and zoisite are common. Rarer and less persistent minerals include ac­tinolite, anatase, andalusite, biotite, muscovitt, diopside, hypersthene, kyanite, pied­montite, sillimanite, titanite, tremolite, and wollastonite. Bullard's (1942) description of the heavy minerals from the adjacent beach sand applies also to the heavy minerals from the study area. Relative abundances of the important mineral species are graphi­cally indicated on maps described in the following paragraphs. Hornblende in the area was of two types, the blue-green soda-rich variety so characteristic of the Colorado River drainage area and the more common green-brown variety. Garnet carried by the present Brazos River is confined to the bottom sediment immediately adjacent to the mouth of the Brazos, and possesses distinctive mammillary etching which definitely characterizes modern Brazos River material. Dullnig (1957) concluded from studying heavy miner­als of the Brazos River that mammillary etched garnet occurs throughout the drainage area of the river system, being most abundant in the Pennsylvanian outcrop. Tables 4 and 5 indicate the relative abundances of each heavy mineral species in percent, and Figures 39, 40, 41, and 42 show the distribution of the more abundant diagnostic minerals. Once again, areas of the circles are directly proportional to percent­age relative abundance. Hornblende exhibits a fairly uniform distribution (Fig. 39) except in the region immediately adjacent to the mouth of the Brazos, where it is deficient, and in the region just offshore to the east, where percentages are high. The pattern for epidote (Fig. 40) is similar to that for hornblende, although for epidote the pattern is much more pronounced. Garnet (Fig. 41) and zircon (Fig. 42), in contrast, indicate a distribution reversed to that of hornblende and epidote. Garnet is extremely abundant in and adjacent to the mouth of the Brazos, but is present only in decreased amounts to the east The same situation prevails with respect to zircon, except that it is even more deficient in the eastern part. For all four of the mineral species plotted, the distribution over the seaward half of the area (the submerged deltaic plain) in general is consistently uniform, and suggests that the assemblage in this area is inherited and that erosion (or non-deposition) is taking place. The distribution could also be explained if the sediment had become homo­geneous by long submergence. This evidence fits in with a consideration of the equilib­rium profile in that an "obstacle" will undergo grading to the extent of bringing it into proper configuration with the profile. Following Bullard (1942), the writer found it very informative to split the heavy mineral suite into a less resistant group ( andalusite, biotite, epidote, hornblende, hyper­sthene, apatite, basaltic hornblende, enstatite, diopside, clinozoisite, zoisite, tremolite, wollastonite, and actinolite), and a more durable group (anatase, garnet, kyanite, monazite, rutile, sillimanite, staurolite, titanite, tourmaline, and zircon). These percent­ages are plotted in Figure 43, the area of the solid-line circles representing the per­centage of more durable minerals, and the area of the dashed-line circles representing the percentage of less resistant minerals. The relationship suggested by the relative distributions discussed above is now emphasized. A less resistant assemblage is domi­nant to the east, while a more durable suite prevails adjacent to the mouth of the Brazos River and to the west. Bullard ( 1942) has analyzed a series of samples from the Brazos River for some distance upstream. His conclusion that the river carries an ultra-stable assemblage of heavy minerals is in agreement with the conclusion drawn previously on the basis of heavy mineral abundance. Since the Brazos River and the bottom sediment in the region of the Brazos delta carry a more durable mineral suite, which is in marked contrast to that characteristic of the remainder of the study area, the obvious conclusion is that deposition of heavy minerals from the Brazos River is diluting the existing suite of less resistant minerals already present in the area. As the present Brazos River suite of heavy minerals is not representative of the offshore area as a whole, some other source must be found. In the outcrops of Cenozoic sedimen­tary rocks from the Colorado River to west-central Louisiana, Cogen (1940, p. 2090­2094) found a hornblende assemblage confined to outcrops within the drainage area of the Colorado River, an epidote assemblage from the Colorado River northeast to the Trinity River where the suite interfingers with a dominant kyanite assemblage, which TABLE 4 Heavy mineral analysis (per cent by number of grains; for each sample counts of 100 grains each were made) Sample no. A-1 A-2 A-3 A-5 A-10 A-15 A-24 D-1 B-2 B-3 B-5 B-10 B-20 C-1 C-2 C-4 C-8 C-10 C-15 C-24 D-7 D-10 D-20 D-25 E-1 E-2 E-3 E-5 E-7 E-10 E-15 E-20 E-30 Actinolite 1 1 Anatase 1 1 1 1 .... Andalusite 1 1 1 1 1 1 Apatite 2 12 13 11 3 4 2 7 6 6 6 6 3 8 9 3 7 9 7 4 2 5 3 5 4 6 4 4 9 2 4 Basaltic hornblende 4 2 5 4 6 4 1 2 2 4 2 1 4 3 2 9 5 3 5 3 3 2 5 4 6 1 Biotite/ Muscovite 4 7 10 2 3 5 2 4 6 I 2 2 l 2 4 3 1 5 1 2 6 4 1 2 l 1 Clinozoisite 2 2 2 3 3 4 3 3 3 2 2 5 3 2 2 l 2 2 2 2 3 3 1 3 Diopsite Enstatite 1 1 2 3 1 2 3 2 5 1 1 1 1 3 2 '2 2 7 2 112 4 3 3 2 113111112 4 1 4 5 2 1 3 2 3 2 22 4 4 8 Epidote 4 13 11 '11 11 14 15 4 1 18 2 8 13 2 10 15 7 11 10 6 13 19 8 9 15 17 18 21 21 16 9 12 18 Garnet 12 13 11 4 12 6 3 14 16 15 7 6 12 21 8 3 19 7 7 8 15 7 9 12 8 14 9 6 8 10 6 7 9 Hornblende 9 10 26 23 24 39 25 14 11 15 25 28 3'3 3 17 31 18 22 30 27 28 29 35 31 26 26 31 17 29 21 20 28 25 Hype:·sthene 1 1 3 6 1 l 1 1 2 1 3 Kyanite Monazite 1 1 2 4 1 3 1 1 1 1 3 1 4 5 3 1 2 4 2 2 211 2 3 3 2 2 1 1 2 1 1 2 4 3 2 1 11 4 1 1 Piedmontite 1 Ru tile 5 9 2 6 3 3 6 2 4 4 2 1 1 14 9 2 1 4 3 5 3 3 1 4 5 2 1 3 Sillimanite 1 1 1 1 1 1 l 1 Staurolite 3 3 1 4 2 4 2 2 4 2 3 2 2 3 4 1 2 1 1 1 5 1 2 3 5 2 6 2 Titanite 2 1 1 3 1 l 3 1 1 1 1 1 1 4 1 1 1 1 Tourmaline 10 4 5 2 6 3 4 22 8 2 12 6 4 11 1 2 6 3 4 2 5 5 4 4 13 4 2 2 8 4 7 8 1 Tremolite 1 1 1 1 1 1 '2 1 '2 1 'l 3 2 3 3 1 1 1 l 1 2 1 Wollastonite 2 1 2 l l 1 1 1 1 1 Zircon 30 19 14 1'2 '21 11 19 23 37 28 21 27 14 27 '28 14 29 29 11 '25 16 27 24 17 4 17 18 17 7 18 18 13 21 Zoisite 6 1 1 2 2 2 2 1 2 l '2 4 1 2 3 5 1 1 3 1 3 5 8 1 1 w C/l C/l 356 Shallow Marine Sediments Offshore from the Brazos River, Texas TABLE 5 Supplement to heavy mineral analysis Sample Per cent Estimated Per cent no. heavy fraclion size (Phi) black opaques A-1 LOO 4.1 49 A-2 0.61 4.4 45 A-3 0.024 4.4 43 A-5 0.88 4.5 24 A-10 0.53 3.8 39 A-15 0.68 3.8 '21 A-24 0.8'2 3.9 36 B-1 0.39 2.5 50 B-2 0.87 4.6 45 B-3 1.14 4.6 59 B· 5 0.63 4.4 34 B-10 0.48 3.8 25 B-20 l.'21 3.5 22 C-1 1.09 3.3 53 C-2 0.29 4.2 81 C-4 0.72 3.6 34 C-8 0.52 3.1 29 C-10 0.67 3.4 38 C-15 1.22 3.6 18 C-24 1.02 3.6 37 D-7 0.97 3.4 37 D-10 1.12 3.3 22 D-20 0.84 3.5 32 D-25 0.80 3.6 24 E-1 0.81 3.6 20 E-2 1.87 4.1 50 E-3 1.13 3.8 36 E-5 0.80 3.9 33 E-7 0.80 4.1 '29 E-10 0.75 3.6 38 £cl5 1.04 3.8 27 E-20 0.85 3.5 24 E-30 1.04 3.5 '25 continues on into Louisiana. A similar petrologic trend in the subsurface Cenozoic for­mations was established by Bornhauser ( 1940, p. 133). The presence of large quantities of hornblende in the Pleistocene Series (and to a lesser extent in the Pliocene-Miocene) of Colorado County, Texas, has been pointed out by Bailey (1923) . Goldstein (1942) divided the border of the Gulf of Mexico into petrologic provinces, including a Western Gulf Province, a Mississippi River Province, and a Transition zone between them. Char­acteristic suites of the Mississippi River and Western Gulf Provinces are similar, except that the former contain large amounts of pyroxene whereas the latter is almost com· pletely lacking in pyroxene; amphibole, epidote, ilmenite, and biotite are common to both suites. As part of API Project 51, van Andel and Poole (1960) have presented essentially the same results as Goldstein obtained. Because kyanite is absent or lacking in significant amounts in the sediment of the study area it may be assumed either that sediment derived from the northeast is not being transported into the area offshore from the Brazos River or that not enough of this material is entering the Gulf to produce a noticeable effect. Hornblende is therefore supplied by either the Colorado or Mississippi rivers. Further­more, pyroxene, particularly augite, is characteristic of the Mississippi River assem­blage, but in contrast these minerals are minor constituents of the Colorado River and Fie. 39. Distribution of hornblende. Numbers in per cent. study area assemblages. The implication, of course, is that the Colorado River is the source of the particular heavy mineral assemblage found offshore from the Brazos. The history of the Colorado River explains the wide distribution of Colorado River material in the northwestern Gulf of Mexico. This river is well known for frequently shifting its lower course during historic time, and a similar prehistoric wandering tendency is recorded in the Pleistocene formations of the Gulf Coast. Wadsworth, who mapped the different stream courses of the Colorado during Pleistocene and Recent time, states (1941, p. 49-50): "After leaving the Tres-Palacios stage {represented by late Beaumont depo­sition} the river flowed southeastwardly to empty, with the Brazos River, into what must have been an inland bay of considerable size. This bay occupied the region of southeastern Matagorda County and southwestern Brazoria County. The presence of such a bay is indicated by occurrences of salt water in shallow water wells found in the vicinity of Hawkinsville. At the suggestion of Weaver, the writer interprets these occurrences as connate Gulf or Bay water trapped in sand lenses at the time the river was building its delta. The Caney stage is so named by the writer because it is believed that Caney Creek, similar to Tres-Palacios Creek, represents the final remnant of a former prominent destributary {sic} channel of the Colorado River. FIG. 40. Distribution of epidote. Numbers in per cent. A large amount of sediments reached sea level in this area at that time, since the two largest rivers in Texas were emptying loads into the Bay only a few miles apart. The resultant delta is one of the most striking on the Texas Gulf Coast. The entire bay area was filled and the mainland was pushed seaward over the barrier beach until it is now in direct contact with the Gulf of Mexico. It is interesting to note that this is one of only two similar places on the Texas coast. The other being in the vicinity of High Island {sic}. The river occupied the Caney stage probably in early Recent times. It main· tained this position until late Recent, and then shifted westward to occupy its present position." The extensive erosion and deposition that followed the last great Pleistocene lowering of sea level, during which time the Colorado and Brazos rivers enjoyed a common delta, account for the characteristic Colorado River mineral assemblage in the northwestern Gulf of Mexico. The heavy mineral suite of the Colorado River would be expected to dominate over that of the Brazos River in this period because the Colorado was deriving its sediments from a primary source area rich in accessory minerals (Central Mineral Region) as opposed to the Brazos, which was reworking sedimentary rock already much reduced in heavy mineral content. Fie. 41. Distribution of garnet. Numbers in per cent. Effects of longshore currents and storm waves on the heavy mineral distribution in 'this same area is effectively summarized by Goldstein ( 1942, p. 84) : "In summation, it would seem that sediment from the present Mississippi River is being swept slowly but surely to the west, diluted by the contributions of streams along the coast, perhaps mixed with sediment carried from the south­west by storms or currents, and exchanging with and being contaminated by reworked Pleistocene sediments upon the continental shelf." Some admixture of material from the Mississippi River and the Rio Grande in the study area is indicated by a trace of basaltic hornblende in all the samples. Basaltic hornblende, however, is an extremely durable mineral and for this reason is not too significant. An admixture of less resistant minerals from the Mississippi River and the Rio Grande would afford much more impressive evidence for mass transportation by longshore currents. CLAY MINERALS Identification. The montmorillonites exhibited properties which divided them into two groups. The first group exhibited a 14 AU periodicity, was difficult to expand to 17 AU and collapsed shortly after treatment, and upon heating developed a diffuse but obvious 14 AU peak. These properties can best be explained in terms of a poorly 5cp) suggests a detrital origin for the chlorite in the study area as contrasted to that of the Rockport area. Quantitative Estimations. From an examination of spectrometer traces of samples spread over the entire study area, it became apparent that a great deal of quantitative variation existed between the samples. In an effort to establish the nature and direction of this variation, a method of quantitative estimations based on comparison of relative peak heights within each specific sample was adopted. In many respects it is similar to the procedure adopted by John, Grim, and Bradley (1954) for use in analyzing recent clay. Clay contained in recent sediment generally possesses relatively poor crystallinity and is intimately mixed in addition to being in a state of flux in regard to its cation exchange properties. For this reason they defy a completely accurate analysis on the basis of clay mineral species, and as a result quantitative estimations are necessarily not as precise as might be desired. Numerical results obtained from quantitative estima­tions therefore have greatest significance when they are rounded off and various small errors cancel out. In order to provide a means of comparison of peak heights within each sample, illite is arbitrarily chosen as unity and the othe~ constituents compared to it. This procedure eliminates the effects of sample to sample variation and, furthermore, compares miner­als of the same relative degree of crystallinity, this last mentioned factor making absolute comparisons with well crystallized reference minerals imp0ssible. lllite is well suited for its role as it is present in all of the samples and possesses a unique, clearly defined peak at 10 AU. Relative abundances of illite and montmorillonite are determined from the glycolated sample by comparing the heights of the 10 Al! and 17 AU peaks. Before these peaks can be compared directly a correction must be made to compensate for the structure factor of montmorillonite type minerals. From the curve of the form factor for mont­ morillonite it is determined that scattering efficiency at angles corresponding to 17 AU exceeds that at angles corresponding to 10 AU by a factor of approximately four. For comparative purposes, then, the 10 AU peak height on the glycolated sample is multi­ plied by four before comparing with the 17 AU peak height to determine the relative amounts of illite and montmorillonite in the sample. The procedure with respect to chlorite and kaolinite is much more complicated be­ cause of the difficulty of distinguishing between the two. Comparison of the heights of the 3.3 AU (illite) and 3.5 AU (chlorite, kaolinite and montmorillonite) peaks is pos­ sible based on the assumption that scattering in this restricted high angle range is roughly comparable for the three minerals. The problem, then, is to assign chlorite and kaolinite their respective portions of the 3.5 AU peak. The contribution of montmorillonite may be automatically subtracted by employing the data from the glycolated sample for chlorite-kaolinite computation. Intensity variations resulting from heating of chlorite minerals (Weiss and Rowland, 1956a and 1956b) indicate that the 14 AU peak result­ ing from ignition to 650°C is, on the average, 5/ 3's as intense as the 3.5 AU peak in the unheated condition. As the form factor for chlorite is extremely variable, depending on the specific type of chlorite mineral in question and on the amount of iron present, this 5/ 3's figure is very general and gives an approximation. The contribution of kaolinite to the 3.5 AU peak on the glycolated sample may be determined by subtraction of the above determined value of chlorite from the peak. As the 3.3 AU peak on the glycolated sample represents both illite and montmorillonite (3.3 being the 5th order of 17), reference must be made back to the untreated sample. This may be done simply by multiplying the intensity of the 3.5 AU peak on the gly· colated slide by the ratio of the intensities of this peak on the untreated and glycolated slides respectively. Finally, a correction for quartz contamination is made by subtracting the intensity of the 4.25 AU quartz peak from the 3.3 AU illite peak on the untreated sample (John, et al., 1954, p. 250). An example of the above procedure is given for sample E-30 in Table 6, which lists TABLE 6 Relative intensity data for sample E-30 17 AU 14AU 10 AU 7 AU 3.5 AU 383 204 765 246 210 173 984 125 265 24 22 159 125 (approx.) lgnitt d • 650°C 3.3 AU Comments 474 442 666 725 (Untreated sample) Illite corrected for quartz (Glycolated sample) Illite corrected 3.5 AU peak corrected (Ignited sample) Chlorite corrected Kaolinite y.,/'"--------~-=--=----­ IV\_/_______ -­......... ~........ ----------------------------------------­ ,/·., //------------­ •6 ----'<' ·./ '~-~,\/~~~~-~-~~~=~~--=------­ '' ' ' . ;--.......... TRAVERSE C v\__/ ---------­ /\..-----·-..,_ ----­ - ·.......-· ~ 2 ", .... -------------------­ ~~......__,.___.._..__,,__~~--;,,~~~---; /,_____ TRAV(RS.{ 8 \ I -----­ '-·-T'"-'::::i<. _.. ~ L><-.. ·., '---------.::.:::-_____ ---------­ .. TRAV(RSf A -­ --':<(~/~---··y/~ ,........-" ',_......./ ............ -----~-.... ··-....... . .. ··---­ 2 ',________________________ 0 '° 2.0 lS IO 1417 AU 1 2] Sompl' Lotol1on /.10''"'"°'"11flllt ---Cf>fot•I• -----l •• lf -··-··-K110 ll(t1/t FIG. 44. Spectrometer traces for sample E-30 FIG. 45. Profiles of relative abundance in parts in the air-dried, glycolated, and ignited states. in ten of major clay mineral constituents. 364 Shallow Marine Sediments Offshore from the Brazos River, Texas TABLE 7 Clay mineral composition for sample E-30 Montmorillonile Chlorite Illite Kaolinite Comments 0.78 0.28 1.0 Parts per one part of illite 37.8 13.6 48.5 Approximate percentage of each constituent 3.5 LO+ 4.5 Parts in 10 of each constituent allowing 10 per cent for material not registering data obtained from the spectrometer traces illustrated in Figure 44, and Table 7, which is a compilation of the results of the analysis. The value for chlorite (Table 6) has been rounded off inasmuch as the approximate corrected value is slightly high. Although the procedure for determining the relative amounts of chlorite and kaolinite is rather complicated and subject to some error, the aggregate percentage of these two minerals with respect to the total clay fraction is small, being on the order of 5-10 per cent; therefore, even large errors in this part of the analysis will not cause any significant variation in the relative percentages of the other main constituents and should not be considered a serious drawback to the pro· cedure as a whole. Final results are presented as parts in 10 of each constituent for the total clay· mineral composition allowing 10 per cent for material not registering, and are rounded off to the nearest half, which is consistent with the accuracy of the method. Table 8 lists the results of quantitative analysis of a number of samples from the study area. The relative nature of this data may be made clear by an example. Sample A-7 contains 4.0 parts montmorillonite, 1.0 parts chlorite, and 4.0 parts illite; that is, the sample has equal amounts of illite and montmorillonite, four times as much illite as chlorite, and kaolinite is absent. The data should not be interpreted as meaning exactly 30 per cent more illite is present than chlorite, and so on. Individual components may be compared from sample to sample, however. In comparing sample A·7 with sample A-24 ( 6.5 parts montmorillonite, 0.5 parts chlorite, 2.0 parts illite) it may be assumed that A-24· contains 25 per cent more montmorillonite, 5 per cent less chlorite, and 20 per cent less illite than A·7. Another factor to be kept in mind is that the clay mineral amounts are based on the clay fraction of the sediment as 100 per cent. In order to make comparisons between different samples in respect to absolute amounts of the different clay minerals present, it would first be necessary to reduce the data in terms of the percentage of total clay in the sample. Distributwn. Distribution of the various clay mineral constituents is shown diagram­matically for each of the traverses in Figure 45. Chlorite content is fairly uniform and is minor in comparison to illite and montmorillonite, the latter two functioning re· ciprocally. There is a suggestion of a trend of increasing montmorillonite from the beach to about 10 miles offshore followed by a subsequent decrease and levelling off in a sea· ward direction. In addition it seems that montmorillonite is low and illite high directly adjacent to the beach. In the farthest seaward portion of the study area all three main clay mineral constituents occur in uniform relative amounts. Any series of random samples might also show the same variation. In order to test the significance of the most pronounced variation (mentioned above at approxi­ TABLE 8 Most probable clay mineral composition in parts in '10 allowing 10 per cent for material not registering Basal Depth relleclion Sample (feel) (AU) Monlmorillonite Chlorile lllite Kaolioile AUC Flood 15.2 3.5­ 1.5 4.0+ (Brazoria, plain Texas) A-1 8 2.0 3.0 4.0+ A-2 23 14.5 3.5­ 2.0 4.0 A-3 33 15:2 3.5+ LS-­ 4.5­ A-5 45 15.8 5.0 LO 3.0 A-7 54 14.7 4.0 LO 4.0 A-10 61 14.7 5.5 LO 2.5+ A-17 84 14.7 3.5 LO 4.5 A-20 92 5.5 LO 2.5 A-24 100 15.2 6.5 0.5 2.0 B-2 22 14.5 2.0 2.0­ 5.5­ B-3 27 1L3 2.0 3.0 3.5+ 0.5 B-5 412 14.9 4.0 L5 3.5+ B-7 56 15.0 3.0+ L5 4.0+ B-10 57 15.2 6.5 1.0 L5 B-17 84 15.8 5.0­ 1.0­ 3.5­ TR B-24 100 15.0 4.0 0.5 4.0 0.5­ C-3 32 15.2 2.0 1.5­ 6.0­ C-4 42 15.3 6.0­ o.5+ 2.5 C-5 51 14.7 4.5+ LO 3.0+ C-7 62 15.5 4.5 LO 3.5 C-8 56 15.4 4.5­ 1.0 3.5+ C-10 67 14.7 7.0 0.5 1.5+ C-17 84 14.4 4.5 1.0 3.5 C-24 100 15.4 5.0 1.0­ 3.5­ D-1 Zl 3.5+ 1.5 3.5+ D-3 37 15.0 41.s+ 1.0 3.5­ D-5 53 L5 2.0 5.5 D-7 61 15.2 4.5­ LO 3.5+ TR D-10 66 14.9 6.0 0.5 2.0 0.5 D-20 85 15.7 5.0 0.5­ 3.0+ 0.5 D-29 100 15.8 5.0­ 1.0­ 3.5 E-2 30 14.7 5.5+ 1.0­ 2.5 E-3 38 15.2 2.5 1.5 5.o+ E-5 49 14.5 6.5­ o.5+ 2.0 E-7 56 14.3 4.5+ 1.0 3.5 E-10 63 15.5 4.5 1.0 3.5 E-30 100 15.0 3.5 LO+ 4.5 mately 10 miles offshore), data for this point was compiled and tested statistically by means of the t-test. Results indicated a probability of 0.17. A sample from the flood plain of the Brazos River at Brazoria, Texas, about 20 miles upstream from the Gulf, indicated 3.5 parts montmorillonite, 1.5 parts chlorite, and 4.0 parts illite. Assuming this ratio to be representative of material arriving in the Gulf, it may be concluded that differential deposition and source area account for the clay minera,l distribution in the study area. This follows strictly from a consideration of the relative proportions of clay mineral constituents and accounts for the mineral­ogical trend only. Volumetric comparis~ns are impossible due to the nature of the analytical method employed. It is observed, then, that illite and chlorite are preferentially deposited from sus­pension prior (closer to shore) to montmorillonite; thus montmorillonite exhibits greatest deposition farther seaward, in this situation about 10 miles offshore. Beyond this point montmorillonite content decreases and at approximately 17 miles offshore ceases, probably marking the offshore limit of significant deposition of Brazos River material. Seaward, clay mineral character is either inherited from older deltaic sediment or the Brazos suite of clay minerals is being deposited intact; probably at a slow rate. The above conclusions are supported by consideration of the color distribution of clay in the study area. Clay derived from the Brazos River is characteristically red, and because of this property may be easily traced offshore. Despite the olive color of the gross bottom sediment due to organic material, the true color of the clay fraction may be ascertained by simple mechanical separation of the clay or by the addition of a very small amount of oxidizing agent. Red clay extends from the beach out to the shoal area ( 60-foot depth-contour), at which point it tends to become olive. The limit of dep­osition of Brazos River material, as indicated by red clay, is essentially the same as that determined by considering the minerals of the clay fraction. Grim and Johns (1954, p. 95) found similar proportions of clay minerals in the Gulf of Mexico offshore from the barrier islands in the vicinity of Rockport, and also reported an improved crystallinity of the chloritic phase in this offshore region cor­responding to that in the study area. In the writer's opinion no positive evidence exists in favor of diagenesis in the area under discussion. The fact that red color of the clay has not been destroy·ed in such a potentially reducing environment does not favor diagenesis. Higher temperatures neces­sary for thermal modification plus the development of sharp peaks on diffraction pat­terns indicate a detrital source for the clay in question instead of a diagenetic origin. Distribution of the four main clay mineral types in the study area may be summarized as the result of both selective deposition and source area. Furthermore, diagenesis is not causing any significant changes in the clay mineral suite. FoRAMINIFERA A selected group of samples from the study area from depths of 61-92 feet were ex· amined for the purpose of determining all of the species of Foraminifera present. Table 9 shows the results of this study, listing 101 species. Most abundant genera were Elphidium and "Rotalia," and Bigenerina, Bolivina, Bulimina, Cibicides, Cibicidina, Discorbis, Eponides, Nonionella, Planulina, Pseudoclavulina, Quinqueloculina, Recto­bolivina, Reussella, Textularia, Uvigerina, and Virgulina were common. Pelagic genera included Globigerinella, Globigerinoides, and Globorotalia, but were, on the whole, rather rare in the study area. A few pyritized tests were also identified from heavy mineral mounts. The thanatocoenose content of the coarse fraction ( > 4.5cj>) was less than one per cent on the average, indicating either an "old shelf deposit" or a "reworked delta de­posit" (Shepard, 1956, p. 2570). This evidence supports previous statements to the effect that the portion of the study area seaward of the 60-foot depth-contour is an TABLE 9 Distribution of Foraminifera in the area offshore from the Brazos River, Texas Station A-10 C-10 E-10 A-20 C-20 E-20 Depth 61' 67' 63' 92' 92' 76' Ammobaculites salsus x A.sp.A x x A.sp. x x Ammoscalaria pseudospiralis x Bigenerina irregularis x x x x x x Bolivina fragilis x x x B. lowmani x x x B.minima x x x x B. pulchella primitiva x x x x x x B. simplex x x x B. striatula x x x B. subaenariensis mexicana x B. subspinescens x B. sp. x x Bulimina affinis x B. marginata x B. striata mexicana x x B. tenuis x Buliminella cf. bassendor fensis x x x B. elegantissima x x Cancris oblonga x x x x Cassidulina norcrossi australis x Cibicides concentricus x x x x x x C. cf. concentricus x x x x x C. io x x x x x C. robustus x x x x C. umbonatus x c. sp. l x Cibicidina strattoni x x x Discorbis bertheloti x x x x D. candeiana x D. floridana x x D. floridensis x x Eggerella bradyi x Ehrenbergina spinea x Elphidium discoidale x x x x x x E. fimbriatulum x E. cf. fimbriatulum x x x x E. galvestonense x x x x E. gunteri x x x x x x E. incertum mexicanum x x x x x x Elphidium sp. cf. e. koeboeense x x x E. poeyanum x E. translucens x x x Epistominella vitrea x Eponides antillarum x E. haunai x x x x E. polius x x E. regularis x Gandryina (pseudogandryina) atlantica x Globigerinella acquilateralis x Globigerinoides rubra x x x x Globorotalia punctulata x Guttulina australis x x x Gyroidina soldanii altifonnis x Lagena x Loxostomum truncatum x x x x Marginulina planata x Nodosaria x x Nonionella atlantica x x x x x x N. opina x x N. cf. opina x Planulina exorna x x x x TABLE 9-'Continued Distribution of Foraminifera in the area offshore from the Brazos River, Texas Slalion A·IO C-10 E-10 A-20 C-20 E-20 Deplh 61' 6i' 63' 92' 92' 76' Proteonina diffiugiformis x Pseudoclavulina mexicana x x Pullinia bulloides x Pulleniatina obliquiloculata x Quinqueloculina bicostata x Q. compta x x x Q. horrida x x Q. lamarckiana x Q. poeyana x x x Q. cf. vulgaris x Q. sp. cf. q. compta x Rectobolivina advena x x x x Reussella atlantica x x x x x x "Rotalia" beccarii x x x x x x "R." beccarii variant A x x x x x x "R." beccarii variant B x x x x x "R." pauciloculata x x "R." rolshauseni x x x x x " R." translucens x x x x Sigmoilina schlumergeri x Siphonina pukhra x x x Siphotextularia affinis x x x x S. rolshauseni x x Textularia foliacea occidentalis x T. mayori x x x x T. cf. mayori x T. mexicana x x Triloculina trigonula x Uvigerina peregrina parvula x x x U. hispido-costata x Virgulina complanata x x x V. compressa x x V. mexicana x x V. pontoni x x x x x V. spinicostata x x x x old delta. Observation of the coarse fraction also showed most of the individuals to be air-filled, indicating a predominantly living population (Phleger, 1951, p. 82). A comprehensive study of the Foraminifera of the Gulf of Mexico from a depth of about 75 feet on into the Sigsbee Deep was made by Phleger (1951) from samples ob­tained during the 1947 cruise of the Woods Hole Oceanographic Institution research vessel "Atlantis." Two of the traverses of this cruise extend into the study area, and although Phleger does not include data for samples taken from the shallow end of these traverses, a close correlation does exist between the foraminiferal distributions of his deeper water samples and those determined for the study area. Occurrences in the study area, however, do extend the shallow limits (Phleger, 1951 ) of some species into somewhat shallower water. Essential agreement is also present between the study area distribution and the open-Gulf facies of the Mississippi Sound (Phleger, 1954), San Antonio Bay (Parker, et al., 1953), and Mississippi delta (Phleger, 1955) areas. Summary and Conclusions The composite energy spectrum of the study area results in a marked symmetrical configuration of the modern delta of the Brazos River. This delta is comparable to other modern deltas in that it possesses poorly sorted sandy topset beds, extensive foreset beds dipping at 1-2° and grading from sand and silt to mud and clay in deeper water, and thin bottomset beds. A clay belt lying 8--10 miles off the mouth of the Brazos is also characteristic of the delta. Longshore currents are not significant as far as shaping the delta is concerned, but they do distribute the mineral suite to the southwest. The limit of effective deposition of material from the Brazos is approximately 10-17 miles off­shore in 60-70 feet of water, and beyond this point sand size material is supplied from a source farther offshore. Sediment in the study area can be accurately interpreted in terms of its modality, which is th~ result primarily of sorting by waves and secondarily of source area. From the beach seaward a series of well developed coarse modes, decreasing in size from fine sand to medium silt offshore, are combined with progressively increasing amounts of a poorly sorted fine (clay) mode to about 60 feet of water, where the fine mode is pre­dominant. At this boundary topographic highs occur which contribute a second coarse (sand) mode to the sediment. Material of intermediate size ( 6-10.p) is essentially lack­ing in the area. Skewness and kurtosis, considered independently, are effective indicators of the modal character of the sediment, and when plotted versus one another describe the relative proportions of the modes independent of sorting in any specific sample. Bivariant plots of mean size and kurtosis, mean size and skewness, and standard deviation and kurtosis, also indicate the relative proportions of each mode in the sediment. Development of the individual modes in regard to sorting is evident from the plot of standard deviation and skewness, whereas the plot of mean size and kurtosis indicates the consistency of specific modal grain sizes in a group of sediments. Best sorting oc­curs in the unimodal beach samples, intermediate sorting in the predominantly clay samples, and poorest sorting in subequal mixtures of these two end members. Mean size and standard deviation together shape a trend, the position of which, in respect to absolute values of sorting, distinguishes the littoral and neritic environment from the fluvial environment. Direction to the shoreline is determinable from frequency plots of skewness, predominantly positive-skewed values indicating proximity to the shoreline and predominantly negative-skewed values indicating an offshore location. Topography is reflected directly by mean size and indirectly by other parameters characterizing the modality of the sediments. Mean size and depth vary in uniform manner from shore to the 60-foot depth-contour, a break in slope of the trend occurring at 25-30 feet marking the depth of maximum marine erosion. Specific trends of these two variables distinguish variations in sediment supply at particular localities and, there­fore, are of correlative value. Topographic breaks in slope are precisely marked by abrupt changes in values of standard deviation, signifying poor sorting of sediments at these points due to the mechanics of sorting by waves. Geologic history of the area is reflected in the heavy mineral distribution, which is the result of coalescence of the Brazos and Colorado river deltas during late Pleisto­cene and early Recent time. After these two rivers had built an extensive delta and completely filled in a large bay, the Colorado River once again shifted its course and in late Recent time was discharging into Matagorda Bay. The more durable heavy mineral suite currently carried by the Brazos is diluting the existing less resistant suite in the region immediately adjacent to the mouth of the Brazos. The shoal area seaward of the 60-foot depth-contour represents a submerged deltaic plain formed during the last major Pleistocene lowering of sea level. 370 Shallow Marine Sediments Offshore from the Brazos River, Texas Clay mineral distribution is the result of selective deposition of detrital clay from the Brazos, with no evidence of diagenesis occurring upon deposition. Acknowledgments The writer is indebted to many persons for material help and encouragement during the progress of the work. Foremost has been Dr. Fred M. Bullard, Chairman of the Supervisory Committee, whose friendship, understanding, guidance, and inspiration has been a major factor in the success of the project. Dr. Robert L. Folk has been most helpful in all phases of the work, and his en­thusiasm and encouragement have been an inspiration at all times. During the early stages of the work, Dr. Gordon Gunter and Dr. Henry Hildebrand, of the Institute of Marine Science of the University of Texas provided assistance in carrying out the sampling. A grant for equipping the boat was secured by Dr. D. E. Feray and Dr. H. E. Nelson of the Mobil Oil Company Research Department, who also provided sampling gear, information, and advice. The writer is also indebted to Professors R. K. Deford and S. P. Ellison, the Depart­ment of Geology of the University of Texas, for suggestions and criticisms in the preparation of the final report. Drs. M. A. Hanna, R. J. LeBlanc and Hugh Bernard, all of Houston, suggested the problem and assisted in getting the work started. Dr. F. P. Shepard, Scripps Institution of Oceanography, made available information concerning American Petroleum Institute Research Project 51, as well as giving advice on various aspects of the work. Finally', Mr. C. E. 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Petrol. 27: 23--26. Fox, M. P. 1931. Improving the Brazos River. Civ. Engng. 1: 287-292. Geyer, R. A. 1950. Bibliography of Gulf of Mexico. Tex. J. Sci. 2: 44--92. Goldstein, August, Jr. 1942. Sedimentary petrologic provinces of the northern Gulf of Mexico. J. sediment. Petrol. 12: 77-84. Grim, R. E. 1934. The petrographic study of clay minerals-a laboratory note. J. sediment. Petrol. 4: 45--46. I.rim, R. E., and W. D. Johns. 1954. Clay mineral investigation of sediments in the northern Gulf of .Mexico, pp. 81-103. In Clays and Clay Minerals, Nat. Acad. 'Sci., Nat. Res. Council Puhl. 327, 498 p. Hjulstr~mm, Filip. 1939. Transportation of detritus by moving water, pp. 5--31. In Recent marine sediments, a symposium. Amer. Assoc. Petrol. Geol., Tulsa. Inman, D. L. 1949. Sorting of sediments in the light of fluid mechanics. J. sediment. Petrol. 19: 5'1-70. ----. 1952. Measures for describing the size distribution of sediments. J. sediment. Petrol. 22 : 125--145. Inman, D. L., and T. K. Chamberlain. 1955. Particle-size distribution in nearshore sediments, pp. 106-127. In Finding ancient shorelines, a symposium, Soc. Econ. Paleontologists and Minera­logists, Spec. Puhl. 3. lppen, A. T., and P. S. Eagleson. 1955. A study of sediment sorting by waves shoaling on a plane beach. Beach Erosion Board Tech. Memo. 63, Corps of Engineers, Washington, D.C., 8'3 p. Johns, W. D., R. E. Grim, and W. F. Bradley. 1954. Quantitative estimations of clay minerals by diffraction methods. J. sediment. Petrol. 24: 242-251. Johnson, J. W. 1956. Dynamics of nearshore sediment movement. Bull. Amer. Assoc. Petrol. Geo!. 40: 2211.-:2232. Keulegan, G. H., and W. C. Krumbein. '1949. Stable configuration of bottom slope in a shallow sea and its bearing on geological processes. Trans. Amer. geophys. Un. 30: 855--861. Krumbein, W. C. 1934. Size frequency distributions of sediments. J. sediment. Petrol. 4: 65--77. Krumbein, W. C., and E. Aberdeen. 1937. The sediments of Barataria Bay. J. sediment. Petrol. 7: 3--17. Krumbein, W. C., and F. J. Pettijohn. 1938. Manual of sedimentary petrography. Appleton-Century­ Crofts, Inc., N.Y., 549 p. Kuenen, Ph. K. 1950. Marine geology. John Wiley &Sons, N.Y., 568 p. Lohse, E. A. 1952. Shallow-marine sediments of the Rio Grande Delta. Ph.D. Dissertation. Univ. Tex., 113 p. Mason, M. A. 1953. Surface water wave theories. Trans. Amer. Soc. Civ. Engin. 118: 569. Mattison, G. C. 194S. Bottom configuration in the Gulf of Mexico. J. Coast and Geod. 'Sur. 1: 76-82. Milner, Henry B. 1952. Sedimentary petrography. Thomas Murby & Co., London, 666 p. Odem, W. I. 1953a. Delta of the diverted Brazos River of Texas. Master's Thesis. Univ. Kansas. Shallow Marine Sediments Offshore from the Brazos River, Texas ----. 1953b. Subaerial growth of the delta of the diverted Brazos River, Texas. Compass 30 (3) : 172-178. Parker, Frances L., F. B. Phleger, and J. F. Peirson. '1953. Ecology of Foraminifera from San Antonio Bay and environs, Southwest Texas. Cushman Fdn. Spec. Puhl. 2, 75 p. Phleger, F. B. 1951. Ecology of Foraminifera, northwest Gulf of Mexico. Part I. Foraminifera distribution. Mem. geol. Soc. Amer. 46, 88 p. ----. 1954. Ecology of Foraminifera and associated microorganisms from Mississippi Sound and environs. Bull. Amer. Assoc. Petrol. Geol. 3-8: 584-647. ----. 1955. Ecology of Foraminifera in southeastern Mississippi delta area. Bull. Amer. Assoc. Petrol. Geol. 39: 71'2-792. Phleger, F. B., and F. L. Parker. 1951. Ecology of Foraminifera, northwest Gulf of :Mexico. Part II. Foraminifera distribution. Mem. geol. Soc. Amer. 46, 61 p. Post, R. J. 1951. Foraminifera of the South Texas coast. Puhl. Inst. Mar. Sci. Univ. Tex. 2(1): 165-:176. Price, W. A. 1953. The classification of shorelines and coasts, and its application to the Gulf of Mexico. Dept. Oceanogr. A&M College of Tex., Contr. 15, 111 p. Unpublished. ----. 1954'a. Shorelines and coasts of the Gulf of Mexico, pp. 39-66. In Gulf of Mexico: Its origin, waters, and marine life. Fishery Bull. 89, Fish and Wildlife Service, Washington, D.C., 604 p. ----. 1954b. Dynamic environments: Reconnaissance mapping, geologic and geomorphic, of continental shelf of Gulf of Mexico. Trans. Gulf Coast Assoc. Geol. Soc., Houston .t: 15-107. Rogers, A. F., and P. F. Kerr. 1942. Optical mineralogy. McGraw-Hill Book Co., N.Y. 390 p. Scruton, P. C. 1955 Sediments of the eastern Mississippi delta, p. 21-51. In Finding ancient shore­lines, a symposium, Soc. Econ. Paleontologists and Mineralogists Spec. Puhl. 3. Shepard, F. P. 1956. Marginal sediments of Mississippi delta. Bull. Amer. Assoc. Petrol. Geo!. 40: 2537...:2623. Shepard, F. P., and D. G. Moore. '1955. Central Texas coast sedimentation: Characteristics of sedimentary environment, recent history and diagenesis. Bull. Amer. Assoc. Petrol. Geol. 39: 1463-1'593. Shepard, F. P., F. B. Phleger, and Tj. H. Van Andel, (ed.) 1960. Recent sediments, northwest Gulf of Mexico. Amer. Assoc. Petrol. Geol., Tulsa. 394 p. Tenth annual report of the State Engineer, 1930-1931, New Mexico. Trask, P. D. 1955. Movement of sand around southern California promontories. Corps of Engineers, Beach Erosion Board Tech. Memo. 76: 31. U. S. Congress. 1948. Freeport Harbor, Texas: House Doc. 195, 81st Congr., 1st Session. ----. 1953. Gulf shore of Galveston Island, Texas, beach erosion control study. House Doc. 218, 83rd Congr., 1st Session. ----. 1957. Freeport Harbor, Texas, engineering report. House Doc. 433, 84th Congr. 2nd Session. Van Andel, Tj. H., and David M. Poole. 1960. Sources of recent sediments in the northern Gulf of Mexico. J. sediment. Petrol. 30: 91-122. Wadsworth, A. H., Jr. 1941. Lower Colorado River, Texas. Master's thesis. Univ. Tex., 61 p. Wave statistics for the Gulf of Mexico off Caplen, Texas. 1956. Corps of Engineers, Beach Erosion Board Tech. Memo. 86. Weiss, E. J., and R. A. Rowland. 1956a. Effect of heat on vermiculite and mixed-layered vermiculite­chlorite. Amer. Min. 41: 899-914. ----. 1956b. Oscillating heating X-ray diffractometer studies of clay mineral dehydroxylation. Amer. Min. 41 : 117-126. Wiegel, R. L., D. A. Patrick, and H. L. Kimberly. 1954. Wave, longshore, current, and beach profile records for Santa Margarita River Beach, Oceanside, California, 1949. Trans. Amer. geophys. Un. 35: 887-896. Experiments With Engineering of Marine Ecosystems1 HowARD T. ODUM,2 WALTER L. S1LER,3 RoBERT J. BEYERS,• AND NEAL ARMSTRONG• Abstract Moderate sized ecosystem cultures were attempted in concrete ponds simulating some principal bay types found on the Texas Coast: (a) the reef-plankton brackish bay, lb) the grassy bottom, and (c) the blue-green algal flats. Processes and successional changes within the engineered systems were monitored with diurnal curve methods. Some general aspects of photosynthesis, community respira­tion, and organismal dominance were similar to those of the bay prototypes. The relative role of respiration and reaeration was delimited in several experiments. In a sequence of extreme salinity shocks, one oyster reef-hay system exhibited rapid metabolic recovery and suc­cessive diatom blooms like that in San Antonio Bay. Some experimental means for partial replication of artificial ecosystems were tested with concrete reef ponds in triplicate. High alkalinity regimes at controlled salinity were developed with evapo­ration and freshwater inflow sequences like that in some Texas river estuaries. pH control was also demonstrated with carbon dioxide gas injections from tanks. Over a six-month period a semi­anaerobic system replaced an aerobic system. It was shown that a pollution-resembling syndrome could gradually emerge from a more normal aerobic system where there was initial inorganic nutrient ferti­lization. The graphs resembled oome based on data from upper Galveston and Nueces Bays. The low nighttime oxygen regime was a climax for the summer weather regime. Pyrheliometer data were used to compute efficiencies of gross photosynthesis ( 0.8 -3%), in utilizing the visible wave lengths somewhat less than in the bay prototypes. In a large concrete pond, a grassy bottom system without stratification provided populations of diatoms, zooplankton, and foraminifera with diurnal variations, trace element concentrations, and metabolic quotients like those in Redfish Bay and Aransas Bay. In very shallow ponds, heavy blue-green algal mats once transplanted, were maintained with large diurnal oxidation and reduction changes and high metabolic quotients like those in parts of the Laguna Madre. Some similarity of processes and concentration levels maintained in these artificial ecosystems may justify their use for controlled experimental study of the bays. Introduction In previous papers measurements of gross photosynthesis and system respiration were reported for various bays along the Texas coast (Odum and Hoskin, 1958; Odum and Wilson, 1962; Odum, 1963; and Odum, Cuzon, Beyers, and Allbaugh, 1963). The metabolic measurements indicated the functional state of these ecosystems under in­fluences of seasonal change, pollution, dredging, and other experimental changes. In such large bays, the investigations were restricted to the natural experimental situations fortuitously provided. For further study of these bays, some smaller models were needed in which controlled experimental manipulations might be feasible. 1 Aided by the National Science Foundation through grant NSF G-13160 for the study of Ecological Microcosms, the Public Health Service, Grant WP 00204-03 for the study of abnormal marine eco­systems, and the Atomic Energy Commission Contract AT (40--1) 2580 providing funds for pond systems. 2 Institute of Marine Science, The University of Texas, Port Aransas, Texas; present address: Puerto Rico Nuclear Center, Rio Piedras, P.R. 3 Department of Geology, The University of Texas, Austin, Texas. 4 Institute of Marine Science, Port Aransas. In I960 and I96I, to meet the need for experimental ecosystems, plastic and concrete ponds were built. Attempts were made to develop formulae for culturing ecosystems with ecological engineering methods. By selection of depth, salinity, and mechanism of cir­culation, conditions in several bays were simulated and these ponds were heavily seeded with water, muds, and organisms from the several bay prototypes. This is a report of the metabolic patterns which resulted in 4 types of ecosystem cultures in these ponds. Conditions in the pond systems were devised to simulate three important bay eco· system types. The first type was the low salinity, turbid bay containing oyster bars in which a biogeochemical cycle was maintained that included the phytoplankton-produc­ing water circulating over the concentrations of sessile reef consumers, filter-feeding and releasing nutrients from the reefs. Copano, San Antonio, and Matagorda Bays were examples. A plastic system (Fig. IA) in I960 was continued with concrete systems in I962 (Fig. IB). The second type was the shallow grassy bottom bay at about 309'00 with much of the photosynthesis by benthic plants such as parts of Redfish and Aransas Bays. The large pond (Fig. IC) was used. The third type was the system of blue-green algal mats carpeting the thin-water flats of part of the Laguna Madre often under hypersaline conditions. Shallower, smaller ponds were used for these (Fig. ID). ECOSYSTEM CULTURING, ECOLOGICAL ENGINEERING Experiments with small microcosms have been useful in showing some of the abstract general patterns of succession, climax, population structure, and biogeochemical cycling that are observed in larger natural ecosystems. Because of their small size they could be replicated and manipulated in controlled experiments at the ecosystem level of study (Odum and Hoskin, I957; Beyers I962, I963a, 1963b). A logical continuation was the culture of somewhat larger experimental ecosystems in concrete tanks so that some of the larger-scale processes might be included such as larger animals, larger genetic reservoirs, water current systems, natural lighting fields, larger geochemical reservoirs, and sea-air exchanges. Such larger microcosms may serve as simulators of the expansive natural systems where enough of the dominant or­ganisms and controlling processes can become established. The culture of ecosystems thus may provide means for study and eventual management of larger ecosystems. For example, can species of commercial interest be most simply managed by culturing the ecosystem in which they are dominant? In a previous commentary (Odum, I962), ecological engineering was defined as en­vironmental manipulations by man using small amounts of supplementary energy to control systems in which the main energy drives are still coming from natural sources. Formulae for ecological engineering may begin with natural ecosystems as a point of departure, but the new ecosystems which develop may differ somewhat since boundary conditions established in the engineering process are different. Thus attempts to culture some marine ecosystems in ponds are also experiments in ecological engineering of new systems because of such special conditions as pumped circulation, tank walls, constant salinity, and diminished imigration from larger popula­tion reservoirs. FIG. I. A. Plastic oyster reef pond system with island and circulatory pump. B. Triplicate reef ponds in concrete. C. Grass Pond. D. Blue-green mat ponds. Methods MEASUREMENTS Diurnal curve methods for study of photosynthesis and respiration were followed as described in other papers on oxygen (Odum and Hoskin, 1958; Odum and Wilson, 1962) ; on pH-C02 (Beyers and Odum, 1959; Beyers, et aL, 1963) . Diurnal curves were very uniform and regular without the complication of diurnally varying current velocities found so often in field measurements. However, reaeration constants in the reef ponds were a function of the stirring rates in the ponds with pumps. Reaeration constants for the plastic pond and the grass pond were estimated from the graphs on the limiting premise of constant nighttime respiration. This older pro­cedure overestimates the diffusion constant because it includes any change in nighttime respiration rates as part of changes in reaeration rate. In the triplicate reef ponds an experiment was conducted to infer the reaeration con­stant comparing a plastic covered pond with one not covered as reported in Fig. 2. Fol­lowing a winter shut-down period, new oysters and other reef components were added and the ponds interpumped for two days. After ponds were again isolated on May 3-4, a heavy polyethylene transluscent sheet was placed on top of the surface of pond number 1 with less than 1 % of the water surface exposed to air. Pond 2 was left uncovered. Evi­dence that the oxygen patterns of the ponds were similar was obtained May 6-7 with both ponds uncovered. Since insolation was less that day as indicated by the pyrheliom· eter the May 6-7 data are not a perfect control on the plastic experiment May 3-4. The two May 3--4 diurnal oxygen curves (covered and uncovered) were plotted to­gether for comparison (Fig. 2). The rates of oxygen decrease at night were greater in the covered pond. The difference between the rates of night decline in the two ponds divided by the saturation deficits provided a reaeration coefficient that was used for computing oxygen metabolism values in these ponds (0.5g 0 2/m3/ hr at 100% deficit). That this coefficient led to oxygen data in agreement with pH-C02 method with a night­time RQ of 0.7 to 1.1 was a check on the approximate accuracy of the reaeration constant used. Rate of change graphs corrected with this constant show a decline of respi­ration between sunset and sunrise as already studied extensively by Bey'ers (1963a, 1963b) in other systems. When the constant respiration assumption is made in the old procedure, a reaeration constant between 1 and 2 g oxygen per m3 results. As discussed elsewhere (Odum, Beyers and Armstrong, 1963) the respiration decline at night is expected to be maximal in a system like that of the reef ponds in which nanoplankton are important and less important in systems with more plant storage capacity for labile new photosynthetic products like the benthic systems including the grass pond and the blue-green mats. For the shallow blue-green mat ponds, a reaeration constant of 1 g/m3/hr at 100% deficit was used based on studies of other shallow environments with benthic corr. munities (Odum and Wilson, 1962) . Application of the Ohle ( 1953) test for Winkler interference was made in the ponds with results similar to findings in the bays. Winkler results were not more than a few tenths of a mg/l off in aerobic conditions, but larger errors 1 mg/1 or more developed during the low oxygen periods late at night. Thus, as indicated in Table 1, Ohle correc­ Reef Ponds-Reoerotion Experiment 15.6%0 10 0 2 Moy 3-4, 1963~-. ,---:· Mg/I . ~ . . 6\ 6 ~ 0 ~­Pond 2 ~6(:, open \ jl~,Q'fl·D \~ . ·6 0 5.0 '',,{'l 4'' ·. hf--~ Iii: Pond I covered by _Y c,... polyethylene sheet 0 0 5.0 0 Pyrheliometer ~100 0 ..c N'-.. E ' u 0 u O> pH 9.0 / Moy 5 -6, 1963 ------ _L----­ _.,,-------------------­ -___ .... -~­ \ 2 Moy 3, 1963 8.000 06 12 18 00 HOUR S Fie. 2. Comparison of diurnal oxygen graphs in interpumped triplicate ponds with and without plastic sheets resticting reaeration, May 3-6, 1963. pH records are for uncovered ponds. The diurnal records of total insolation were made by an Eppley pyrheliometer and the visible fraction computed by subtracting the values when covered by an RG-8 Schott filter which transmits in the infra-red. Experiments in Engineering Marine Ecosystems TARLE 1 Ohle Analyses l 2 3 4 5 Winkler Winkler Ohle Correcled Anomaly Plus Ohle only (2-3) (1-4) Reef Pond, Sept. 12, 1962 Pond 1 0600 0 0 0 2.72 2.60 2.65 1.99 1.44 1.98 Pond 2 1830 0 11.37 11.37 11.47 2.66 14.21 14.11 14.06 1.80 2.55 2.52 2.55 .86 -.86 Mat Pond, July 3, 1962 Pond 1 1500 11.40 14.13 14.14 13.92 13.49 14.95 2.54 0.17 0.28 11.59 -0.19 Mat Pond, Sept. 4, 1962 Pond 1 1845 13.81 7.38 7.33 14.44 9.02 8.82 0.22 0.08 0.14 14.22 -0.41 Pond2 0540 7.35 0.0 0.0 8.92 0.28 0.59 0.11 0.0 0.0 8.81 -1.46 Mat Pond, Sept. 3, 1962 Pond 1 1900 0.0 6.93 2.88 0.44 3.42 4.24 0.0 1.35 1.13 Blue-green Mat Transplanted to Laboratory Cylinder, Sept. 5, 1962 0600 4.90 12.4 10.6 3.83 14.4 12.2 1.24 1.03 1.80 2.59 -2.31 Sept. 5, 1962 1800 11.50 9.20 14.70 12.40 13.3 11.10 18.10 15.40 1.41 0.0 1.35 2.39 11.89 -0.39 12.l 14.9 1.25 13.65 -1.55 tions are required in the night periods. That this occurs in fertile marine systems without pollution is of considerable interest. Since metabolic rates are computed as changes, the effect on computations of rates becomes significant mainly in the computation which correc~s for reaeration. In this paper the original Winkler analyses are shown and the Ohle correction also indicated where known, but the metabolic rates are made with an Ohle correction. Further evidence for a diurnal change in Winkler interference is pro· vided in a paper on abnormal bays (Odum, et al., 1963). Since the pH-C02 method involves neither reaeration correction nor interference cor· rection c~mparirnn of the metabolic results of the two methods concurrently are im­portant. Metabolic quotients are computed where data are available (Table 2). Gror photosynthesis and 24 hour respiration rates are related on a molar basis (C02/0c). As indicated in the several examples in the figures, a slanted straight line is drawn --om pre-dawn respiration to post-sunset respiration for this purpose. The : lancy-Okun lead-silver membrane electrode for oxygen was used in the systems with n'" ~naerobic conditions to show the presence of some oxygen and confirm the interfcr~'.1ce with the Winkler analyses indicating zero at that time. Phosphorus measure­ TABLE2 Metabolism, Metabolic Quotients, and Efficiencies of Gross Production based on 50% of pyrheliometer records. Metabolic Oxygen Carbon quolient Efficiency Pond g/m2/day g/ m2/day co2102 O,X4.5 number p R p R AQ RQ % of visible Reef Ponds (See also Fig. 6) March 23-25, 1962 1 9.3 11.5 2.8 3.1 0.80 0.72 2.1 2 12.5 11.4 2.3 3 16.7 14.6 3.3 March 25-26, 1962 1 1.9 2.8 March 26, 1962 1 .... 1.6 1.7 ··-· April 18-19, 1962 1 5.8 11.6 0.9 June 7-8, 1962 11 6.9 6.8 1.0 2 0.4 10.8 1.6 3 6.7 7.3 1.0 July 19-20, 1962 1 7.7 12.2 1.4 2 5.8 8.7 2.6 2.5 1.22 0.78 1.0 3 6.6 9.6 1.2 August 8-8, 1962 1 7.8 9.5 0.8 2 8.9 10.7 3.8 3.5 1.1 0.88 0.9 3 5.8 10.0 0.6 Sept. 11-12, 1962 1 13.7 13.7 2.2 2 15.2 19.2 2.4 3 4.7 9.5 0.7 Sept. 12-13, 1962 ¥.! covered with plastic 1 14.0 17.0 2.2 Uncovered 2 13.2 14.1 2.3 May 3-4, 1963 With plastic cover 1 6.6 7.4 .... 0.7 Uncovered 2 5.1 5.8 2.2 2.0 1.2 0.7 0.6 May 6-7, 1963 1 5.1 7.1 2.5 2.4 1.7 1.1 1.05 2 5.1 4.8 1.05 Grass Pond (Also see Fig. 11) June 8, 1961 3.3 4.8 1.7 1.9 1.3 1.06 0.5 June 15-16, 1961 2.8 3.8 1.2 0.72 1.1 0.5 0.7 July 12-13, 1961 4.8 3.8 4.0 1.5 2.2 1.0 0.6 Blue-green Mat Pond July 3-4, 1962 5.2 5.4 5.2 5.2 2.7 2.5 0.5 July 22-23, 1962 1.3 1.3 Aug. 6-7, 1962 12.3 12.0 Plastic Pond (See also Fig. 4) Nov. 6, 1960 1.5 0.1 1.2 0.7 2.1 1.9 ments were made with perchloric acid digestions following Zwicker and Robinson (1944) . Iron analyses were made by Miss Lorna McGough and Dr. Patrick Parker using the phenanthroline method of Lewis and Goldberg (1954). Alkalinites were titrated with dilute HCl to an end point of pH 5.0 indicated with a glass electrode. Except during August, 1961, and August, 1962, continuous recordings with a 50 junction Eppley pyrheliometer were taken using an amperometric recorder of Yellow Springs Instrument Co. Calibration was made using the electrical voltage equivalent of radiant energy supplied by the Eppley Co. and by means of amperage measurements with a Weston-calibrated microammeter. To obtain the fraction available to photo­synthesis, the pyrheliometer was covered with a box made of RG-8 Schott filters which excluded the visible rays available for photosynthesis but transmitted the infra-red rays not usable in photosynthesis. The difference between the two was taken as available energy for primary production. See the example in Fig. 2. To compute efficiency where the filter was not used, visible light was taken as 50% of total pyrheliometer record. In much of the field work reported in previous papers, a hand light meter with an approximate foot-candle scale provided by the manufacturer was used (General Electric Golden Crown Exposure Meter, Type PR3, with an incident light attachment). The ease of use, sensitivity, portability, and low cost made the meter useful in the field. Whereas it is not possible to convert approximate foot-candle data to energetic data without detailed analysis of the spectral composition, in practice where there are some similarities in spectral composition of incident insolation it may be possible to obtain some empirical relations between the foot-candle data and the pyrheliometer data for some representative sunny conditions such as clear sky and broken cumulus. Foot-candle and pyrheliometer graphs were plotted as overlays in several diurnal graphs in this paper. A graph of foot-candle estimates with the GE meter is plotted as a function of pyrheliometer readings in Fig. 3. This graph provides a rough method for converting one type of data to the other where only one was available in similar circumstances in the south Texas area. The abscissa is 50% of total insolation so that foot-candle estimates can be converted to available energy for photosynthesis. The dashed line is extremely • • 10,000 ff) Q) "'O c: 0 u 5,000-­ - 0 0 LL 2 g cal/cm2/hr 50°/o of Pyrheliometer Record Fie. 3. Graph of foot candles from a General Electric hand exposure meter as a function of 50% of the total radiation from an Eppley Pyrheliometer. approximate. Use of the Schott filter indicated that percentages of total insolation in the visible were from 45 to 80% depending on clouds. Total organic matter in water samples, and the organic matter in millipore filtrates were analyzed according to the persulfate digestion and infra-red C02 method of Wilson ( 1962). After the experience with cracking of the large pond in Hurricane Carla, later ponds were constructed with enough reinforced steel and basic foundations on creosote pilings jetted 12 feet into the sand to prevent damage from undermining of the sand by hurri­cane waves and currents. DIURNAL SAMPLING Buoy With the help of Dr. Marcel Gres and Tracor, Inc., of Austin, Texas, a floating fiber­glass buoy was developed for filling 125 cc glass stoppered bottles over a 24 hour period. A timing motor operating from a storage battery operated a solenoid valve and a selector switch allowed the bottles to fill every three hours by gravity fill. Originally, the buoy was designed to take samples for later measurement of oxygen and pH, but no satisfactory method was found for preservation since all of the preservatives and poisons yet tested either changed oxygen contents or interfered with the Winkler method. Curves which duplicated those in the outside water were obtained only in turtle grass beds in which the plankton was negligible and the waters entering the buoy were thus effectively removed from the metabolism of the community. Although designed with a chamber for ice, tests of the buoy operating with ice indicated inadequate preservation. The mechani­cal system of the buoy was found to work adequately in the experimental ponds, and the buoy may become useful with diurnal sampling studies involving sampling for radio­tracers and other chemical entities not subject to metabolic change while in the bottles. Tracor Corp. manufactured the buoy for $800. PONDS AND ·SEEDING SEQUENCES With the reasoning applied in the microcosm studies, organic biomass and essential inorganic constituents were transferred from the environmental prototype to the tank so that the release of chemicals from respiration and decomposition would provide the inorganic ratios most suitable for the plants of that system and inversely so that the plant species thus competing with that inorganic composition would have the proper nutritive ratio for the consumers normally in that system. Then the dominant boundary conditions of the prototype were set with respect to water depth, circulation rate, and sediment type. Finally species from the prototype environment were added in quantity and diversity including micro-organisms, plankton, benthic animals, and small fishes. Where replications were desired, ponds were intermixed with inter-pond pumping. The ecosystems which emerged in a few days were the result of organizational influences such as natural selection and behavioral responses of species within the system. A moderately large metabolic rate resulted in each of the experimental sequences. Plastic Reef Pond. In July, 1960, a pond ecosystem simulating a low salinity bay was improvised by laying a black sheet of polyethylene in an excavation in the sand 4.9 by 5.1 m as shown in Fig. IA. A small island was arranged at one end, and a live oyster reef from San Antonio Bay was introduced into the narrow channel 0.6 m wide made by the island. A pump was arranged to draw water from the broad part of the pond discharging across the reef at about 0.2 m/ sec. Thus the pond water was being ~82 Experiments in Engineering Marine Ecosystems moved from bay area to reef simulating bay-reef relations of the oligohaline Texas bays. In several diurnal curves, oxygen sampling was done just above and below the rapid current zone of the reef and the values reported separately (Fig. 5). Fresh water was added to balance evaporation. The area of reef to total photosynthetic surface was 1 to 20 like that in a diagram for the Copano Bay area given by Hedgpeth (1954) . Twenty­eight grams of nitrogen and phosphorus fertilizer were added. There were immediate blooms of diatoms with a rich brown color. Then the patterns were followed through the summer and during the fall. In this period, there were interruptions due to heavy rain­floods which overran the pond decreasing the salinity and covering the pond bottom with sand and sediments from outside. In this pattern of even'.s, conditions in the upper bays were simulated. After one such flooding all the oysters were killed and replaced. It was obvious during the fall experiments that the plastic had been punctured, and the pond was in exchange with the ground water. At the end of the experiment, the system was allowed to become entirely fresh. Triplicate Reef Ponds in Concrete. In the fall of 1961, the arrangement for the reef­ 1960 1961 1960 1961 Fie. 4. Seasonal graph of salinity, metabolism, and the sequence of events in the plastic oyster-reef pond system (Fig. IA). Mg/I 0 12 10 8 6 4 2 0 12 10 8 6 4 2 0 12 10 2 0 Aug. 4-5, 1960 25.4 °loo , , , , 00 06 12 18 00 HOURS FIG. 5. Four diurnal curves of oxygen in the plastic oyster reef systems. Measurements were made upstream and downstream from the reef assemblage. island-hay plankton system in the plastic pond was constructed in triplicate in concrete as shown in Fig. lB. Sea water, sediment, and reef materials were introduced and seeded as before. Depth was adjusted to 0.52 m and salinity to about 16 %o· The area of water in each pond was 11.4 m2 and the volume was 5.87 m3• The three ponds were homogenized by interconnecting intake and discharge hoses of the 3 pumps. Then the pumps were returned to their single pond function of circulating water from the broad area to the reef. Metabolic patterns were compared between the three ponds. In setting up the three ponds the first time 5 pounds of nitrogen and phosphorous fertilizer was added on March 19, 1962, (6% N, 12% P20 5, 6% K, Wonder Gro Fertilizer Co., San Antonio, Texas). Very heavy nanoplankton blooms were sustained and anemones, gam­marids, mud crabs, barnacles, and other animals on the reef became very numerous. Few oysters survived, however; rotifers dominated the zooplankton. After a period of 6 weeks without intermixing, differences became noticeable in the ponds. lnterpumping was con­tinued every few weeks. Later in the summer when the pumps became fouled so that circulation stopped, some stratification and the excess of respiration over photosynthesis produced an almost anaerobic nighttime condition. Then when the pumps were returned to adequate function, the ecosystems continued to maintain a near anaerobic nighttime phase. With declining light in the fall, metabolism in the pond and densities of animals on the reef declined also. Salinities were adjusted by adding tap water to balance evaporation to a mark pre­viously established on the wall. The alkalinity of the tap water used was 2.1 milli­equivalents per liter on May 5, 1962, this water being derived from Corpus Christi water mains and ultimately the dam on the Nueces River. A study of alkalinities was made in these ponds under the arrangement of adding high alkalinity fresh water to balance evaporation. Twice in May after sediments were added, carbon dioxide gas from a tank was injected for several hours into the pump intake lowering the pH. The carbon dioxide bubbles entering the pump were completely dissolved in passing through the pump system. A diurnal study of total and filtered organic matter was made by Ronald Wilson on March 24, 1962. For economy reasons, the interchangeable pump units in these experiments were % horsepower "Mitey Mites" with the disadvantage of a bronze impeller which un­doubtedly contributed copper to the systems. Dicharge rates were 62.5, 63.4, and 60.9 liters per minute on May 7, 1963. Grass Pond. In the spring of 1961, a concrete pond 13 m by 11 m and 1.3 m deep was constructed with rounded corners as shown in Fig. lC. In early June turf of turtle grass bottom and associated animals and sediments were brought from Redfish Bay covering the bottom with grass beds in many places and with a layer of sediment throughout. Water to a depth of 0.4 meters was pumped from the inlet nearby. Thereafter, tap water was added as needed to balance evaporation to a mark thus simulating a similar process in the hays where addition of river water tends to balance evaporation. Plankton seeding was continued from many hays during the month. The pond was seined during the month and components of the nekton smaller than about 4 inches were allowed to remain. Diur­nal curves of metabolism were taken with oxygen and pH-C02 methods. Class projects were done on the ecosystem, including a study of foraminifera by Warren Horton and attached diatoms by Alice E. Sharp. Diurnal measurements of a number of variables were made. The effectiveness of mixing under wind stress was studied with duplicate oxygen and temperature measurements. Studies were terminated by Hurricane Carla which flooded and broke the tank September 9, 1961. The cracks have since been repaired and the system is again in use. Blue.Green Algal Mat Ponds. In spring, 1962, additional small concrete ponds were built as shown in Fig. ID. The bottom was covered with a layer of sand. Then on June 28, 1962, partially dry, leathery blue-green algal mats from heavy beds near a bleed-water outfall in the Laguna Madre 3 miles south of the Flour Bluff Causeway Toll Station were collected, stacked, and transported in a station wagon like sheets of burlap. The mats had Microcoleus, lyngbya and other genera as interwoven filaments. These mats were placed over 90% of the bottom sands of the ponds. Sea water was added to a depth of about 10 cm simulating the conditions on the blue-green flats. There­after the water levels were allowed to rise and fall with rain and evaporation. Diurnal measurements were made for comparison with similar measurements in the blue-green mat systems of the bays such as reported by Odum, Cuzon, Beyers, and Allbaugh ( 1963). Results Metabolic rates for all pond experiments are given either m the tables or m the seasonal graphs. REEF POND SYSTEMS The sequences of salinities, metabolism, and events are given for the plastic pond experiment in Figs. 4 and 5, and for the triplicate concrete ponds in Figs. 6-10. PlastU: Reef Pond. The system was exposed to an alternating sequence of sharp salinity changes like that in the bay prototype. The graph (Fig. 4) shows a rapid re­covery of community metabolism following salinity ~hocks even when the salinity changes caused death of the oysters and other dominant populations as on August 11 and Oc­tober 20. The ability of the system to substitute new populations with little interruption of photosynthesis or respiration was also noted in field measurements in Nueces Bay (Odum et al., 1963) . The decline of metabolism during the latter part of the season accompanied decline in insolation and resembled the decline in metabolism in the bays. The slight metabolism on August 11-12 was associated with heavy rain clouds during the day. The evaporation rate was 8 to 12 cm per week. Daily temperature sequences ranged from 28 °C at dawn to 39°C before sunset. With the pump then being used, there was some injection of bubbles. The reaeration coefficients as determined from the diurnal curves (subject to the assumption of constant nighttime respiration) were variable, in part due to the variable effectiveness of the pump, and ranged from 0.8 to 3.0 gm oxygen per m3 per 100% deficit. The diurnal curves were all without anaerobic nighttime phases. P and R were out of phase more than in some experimental ecosystems in which irregular boundary fluctuations were elimi­nated (Beyers, 1963a). A slightly different oxygen concentration was rnmetimes found below the reef stream compared with that above (Fig. 5) the difference representing the metabolic and reaera­tion roles of the reef under the adapted conditions. Possibly significant differences (paired points not overlapping) were present in two of the four graphs, (July 27-28 and August 3-4). Reef Ponds 't::;;' 5 Salinity 20 0/oo 10 QI--­ Alkalinity / L'r~ \" ..0.. -3 ' ' ' ' 3 ' ' /_ _....o ··O ___ \ ··... \ meq ,.--' ·• \ ........_\, ·._ , liter ·._ , '•.\ ()/ \. ,... 2 \"... \ \ \\ /? \ "·. .· ' \\8// ' .-----+--:-:---+---, \0 / pH ' \Id. ' ~ O FEB. MAR. APR. MAY JUNE -JULY AUG . SEPT 1962 FIG. 6. Seasonal record of metabolism, salinities, alkalinities, and the sequence of events in the triplicate reef ponds in 1962. The pH record during the carbon-dioxide gas injection experiments is given as an inset. Reef Ponds March 24-25, 1962 00 06 12 18 00 HOURS Frc. 7. Diurnal record of oxygen content, total insolation, carbon and oxygen metabolic rate, temperature, and organic carbon concentration in the triplicate reef ponds March 24-25, 1962. Reef Ponds June 7-8, 1962 T5 °/oo 10,0 00r--"""T"---ir--"""T"'"".....,.-"'T"""....,..-.,.-~-,.--....,...-,.--_ 10 Mg/I ............ ,', ............... ,,'' ', , ~ I 0 00 06 12 18 00 HOURS FIG. 8. Diurnal record of incoming insolation, foot candles incident, and oxygen concentrations in the three reef ponds June 7-8, 1962. Reef Ponds July 19-20, 1962 17.7 %0 HOURS Frc. 9. Diurnal record of incoming insolation, incident foot candles, temperature, oxygen content, and pH in the triplicate reef ponds July 19-20, 1962. 00 06 12 IS 00 Fie. 10. Diurnal record of incident foot candles, oxygen concentration and rate of carbon and oxygen metabolism in the triplicate reef ponds August 8--9, 1962. In the upstream and downstream data in Fig. 4, the changes in oxygen concentration range from values too small to be significant to changes of 1.0 mg/ 1. With a flow of 0.2 m/sec. through a reef cross sectional prism of 0.6 by 0.1 m or less, the reef metabolism ranges from 0 to 2 g/ m2 per hr as prorated over the 22m2 of the total bay-reef system. Thus the reef at times may have had a metabolic rate dominating the total metabolism, but at other times the metabolic contribution of the reef was minor. Some photo­synthetic contribution from reef algae to the system may be detectable in these upstream­downstream curves as indicated by oxygen increases in daytime July 27-28 and Au­gust 4-5. The changes on July 23-24 suggest aeration. Large variations in the respira­tion of an oyster reef may be consistent with the findings of Collier ( 1959) that oysters pump at widely varying rates in relation to the food concentration. On November 1, 1960, after the reef had been removed, diurnal metabolic measure­ments were taken in which the oxygen ranged from 90 to 150 per cent of saturation. Then, on November 2, a new reef of oysters and barnacles was placed in the island channel and another diurnal oxygen curve was taken on November 3 in which the oxygen ranged from 70 to 125 per cent. Whereas photosynthetic rates were similar (November 1, 1.4 g/m2/day; Nov. 3, 1.6 g/m2/day) the respiration rates increased from 0.3 g/m2/day on Nov. 1to1.9 g/m2/day on Nov. 3. However, a low respiration rate of 0.3 g/m2/day was obtained again on Nov. 6. At peak population the reef held 123 Crassostrea virginica, 410 Brachiodontes exusta, 36 small mud crabs, and many Balanus eburneus and bryozoa. The spectacular diatom bloom contained numbers up to 1300 Pleurosigma sp. and Amphora sp. per square millimeter of bottom ooze. The same species were present in six oyster stomachs in con­centrations 9 to 10 times greater than outside. Although the water remained relatively clear, diatoms were being transported from their prevalent position on the bottom ooze of the system to the stomachs of the reef organiEms via the current system. Increases in the brown blooms were observed after each influx of fresh or salt water. On the evening of August 10 a large number of the heteronereis form of Nereis dumerlii was found swarming on the water surface of the tank, the congregation lasting 2 hours. Triplicate Reef Ponds. The results of the salinity, alkalinity, and circulation manipula­tions are graphed in Figs. 6-10. Whereas the plastic pond experiment simulated oyster-diatom populations of the moderately fertile low salinity reef containing bay, different populations developed in the triplicate ponds resembling most the heavily enriched systems of upper Galveston Bay and Nueces Bay. Most of the oysters did not survive, but there was a very heavy reef growth of other consumers, Balanus eburneus, gammarids, mud crabs, and sea anemones. The extremely productive plankton was dominated by small green nanoplankters and rotifers. The swarm of small animals on the reef was very much like that observed on reefs between Corpus Christi and Nueces Bays in the same season. In the spring and early summer the diurnal range of oxygen was within the aerobic range suitable for most larger animals (Figs. 7-8 ), but by the end of the summer the amplitude of oxygen range had increased so that oxygen values near zero were reached at night (Figs. 9-10). Temporary pump failures caused temporary stratifications and anaerobic nighttime bottom conditions during several days in July. When pump functions were restored, the system continued to develop near-anaerobic nighttime conditions even Experiments in Engineering Marine Ecosystems with sustained mixing. This sequence demonstrated that an enriched bay could follow a succession towards an anaerobic nighttime oxygen condition where radiation and mixing conditions were sustained. Such oxygen regimes provided limits to the number and type of participating animal and plant populations. This experiment indicated that a wide oxygen range pattern once stimulated by some enrichment such as from pollution influx could be self maintaining. Recovery of ecosystems to normal patterns from bay enrich­ment may not be possible without flushout. The three ponds set up in a similar manner, seeded, and then interpumped did produce rough replicates with similar dominant plankton, animal populations, salinities and alkalinities. Replication of metabolic rates was not as good since conditions in the ponds gradually drifted apart over a several-week period. As indicated in Fig. 6, interpumping was arranged several times during the 6-month sequence. The degree to which the repli­cations were maintained can be observed from the graphs of ponds 1, 2, and 3. Whereas interpumping momentarily makes the fluid uniform, the nekton, benthos, and reef com­ponents are sufficiently different to keep metabolic patterns somewhat apart. A study was made of the alkalinity changes that accompanied the high rates of pond metabolism. In March when metabolism did not get an effective start in the bare tanks, fertilizer and a sediment floor was added, followed by tremendous blooms in which the alkalinity was lowered as pH levels became very high. What contribution alkali from new concrete was making at this time is not known. Later, as in all the concrete experi­ments, the walls became heavily coated with a biological encrusting layer thus making the walls similar to the bottom sediments as living biogeochemical exchange surfaces. Then, in April, more seeding with organic matter containing muds contributed to respiration lowering pH levels somewhat. To control the alkalinity range upward and the pH range downward, an experiment was twice made with injecting carbon dioxide into the ecosystem as an ecological engineering technique. As indicated by the graph in Fig. 6, pH was immediately lowered, rising again in several days with increased alka­linity as the free carbon-dioxide added was neutralized by carbonate solution from the sediments. During much of the summer, salinities were held fairly constant by adding the hard tap water to maintain a constant water level of 0.5 m. That little further rise in alkalinity developed indicates an equivalent deposition of calcium carbonate in the ecosystem as in the rapid growth observed in barnacles and mussels on the reef. The increase of alkalinities over that of sea water due to the use of high alkalinity fresh water to balance evaporation apparently duplicates the situation in some Texas bays. Park, et al. (1958) showed the increase in alkalinity to chlorinity ratio in the bays. A series of 22 alkalinities from the Aransas Pass inlet into Baffin Bay via the Corpus Christi and Laguna Madre ranged from 2.9 milliequivalents/1 at Port Aransas through values above 3.0 in the upper Laguna Madre to 4.0 in Baffin Bay (Park et al., 1958) . This system of high alkalinities is favorable for a regime of calcareous depositions in biological components reefs and sediments so that a steady state can develop between evaporation-inflow and losses from deposition and Gulf exchange. Thus the general car­bonate geochemical patterns of the pond sequences were similar to the bay prototypes. Wilson ( 1963) was able to demonstrate direct changes in organic matter in dark and light bottles containing plankton with direct organic matter determinations. The diurnal measurement sequence on March 24, 1962 (Fig. 7) suggests the diurnal pattern to be expected although the method was not sensitive in this situation. Organic matter levels in the water on February 12, 1962, just after the ponds were started, were 5-11 mg/l, not much above that of the Gulf water used to start the ponds. By March, however, the ecosystem was maintaining levels of 19 to 30 mg/l like those in some of the isolated bays like the Laguna Madre and Baffin Bay. It may be postulated that with restricted diversities among the consumer networks, the organic levels in the pond must rise, thus stimulating micro-organism metabolism adequate to balance photosynthesis just as in the bays. It may be suggested that there is a general inverse relation between dissolved organic matter and diwrsity of consumer circuits among higher organisms. The low nighttime oxygen regime favors restriction of species and increase of organic matter. In this sequence the organic matter is entirely self-generated and is not controlled by import or pollution. The energetic input to the triplicate ponds during the summer was from two sources, the sunlight and the circulatory energy supplement supplied from man's civilization as a power supplement. In the absence of this circulatory energy, the processes of photo­synthesis and respiration, each dependent on recirculation of products of one to the other, would have been limited to those circulatory mechanisms paid for from the systems own energy as with fishes, diurnally moving zooplankton, migrating dinoflagellates or pump­ing of reef animals. The pumping rate of 62.2 liters per minute from electrical power supplement contributed 4.2K Calories kinetic energy per square meter per day to the system as compared to 4200K Calories per m2 of visible light received. If, in the absence of such circulation, the ecosystem were circulating nutrients by supporting large nekton at the herbirnre and carnivore levels, the transfer of visible light energy through the trophic lewk thus concentrating power enough to provide movement independent of the medium, would result in the same order of magnitude of power for nutrient circula­tion. In the Laguna Madre, Hellier (1962) found a conversion of gross plant production to fish production of 0.0749(. . In a number of graphs replicate Winkler analyses showed irregularities in the diurnal curve of oxygen at a time when the pump-driven reaeration was unchanging and the light fields were unchanging. These variations appeared, for example, in Figs. 2, 9, and 10. These changes observed in field work have often been attributed to wind variations affecting reaeration and differences in local trajectory, fish schools, etc. In the tanks they apparently represent large changes in the system metabolism such as might be provided by components of the reef pumping or not pumping. The rise in oxygen about midnight or before dawn observed in several curves may represent cessation or decline of some respiratory functions such as pumping. GRASS Pmm The records of metabolism and events in the grass pond are given in Figs. 11-13. Shortly after transplanting and seeding of the large pond a moderately high photo­synthesis and respiration developed which was similar to that in parts of Aransas and Redfish Bays (Odum and Wilson, 1962; Odum, 1963) . During the summer, animal and plant populations developed like those in the bay prototype. Thalassia testudinum, Diplanthera wrightii, and Ruppia. maritima continued to maintain new growths. Benthic FIG. 11. Seasonal record of salinity, temperature, wind at night, reaeration constant for 100% oxygen deficit, system metabolism and the sequence of events in the grass pond. 0/oo oc 20 mph Grass Pond Ju ly 13-14, 1961 0.53m 300..-...............~.--...--.---.-~...............-.--............ Filtered iron Foot Cond !es ,'\ 10,00 I' / /I \ \ Mg/m3 ' ' ~· 5,000 Oi------;----+----+~--~ ' ' ' ' pH ' ' :' ' ' \ ' 8.5 ' 01------T----+----·\ ~---~ o, 8.0l------+---_....-----1----~ Mg/I 5.0 • 100 2.0 T 34 oc 32 30 0 100 28 Transparen cy O/o Salinity ~ 50 0/oo 31 -Jf­ 30 29 0 00 06 12 18 00 06 12 18 00 HOURS HOURS FIG. 12. Diurnal record of incident foot candles, oxygen concentration, temperature, salinity, iron in millipore-filtrates, pH, phosphorus, and bottom transparency in the grass pond, July 13-14, 1961. diatom populations were observed in sediments and water, especially Nitschia closterium and Navicul.a grenville (identified by E. J. Ferguson Wood). The dominant vertical mi­gration of Acartia was verified on August 23, 1961, (Fig. 13). Brown shrimp, Bairdiella, Cyprinodon variegatus, Fundulus similis, and Menidia beryllinia were common. When the pond was examined after draining on September 9, 5-inch oysters and heavy barnacle growths were observed on the walls just as on the solid substrates of the prototype bays. A dense population of bottom foraminifera was observed and studied by Wayne Horton. From his measurements of metabolism per individual with the pH-C02 method in vials, and from 10 bottom counts, he estimated that 5% of the total metabolism (0.030g 0 2/ Gross Pond Aug.31-Sept. 1, 1961 0.5m 33.--..................--................................................................................................... Fie. 13. Diurnal record of salinity, iron in rnillipore-filtrates, and inorganic phosphorus in the grass pond, August 31-'Septernber 1, 1961. Total phosphorus is given for August 21-22, 1961, and concen­trations of the copepod Acartia tonsa are given for August 23, 1961. m2/hr) was attributable to the dominant benthic foraminifera: Ouinqueloculina poeyana and Streblus becarii. The diurnal variations of many properties were explored as reported in Figs. 12-13. The level of phosphorus maintained by the cycles of the ecosystem was 50 to 115 mg/m3, similar to that in the bays (Odum and Wilson, 1962). There was a curious diurnal change in water transparency conspicuous to people in the pond area even without instru­mental measurements (Fig. 12). The per cent transmission to the bottom with a selenium photometer in daylight was 50% in the early morning improving to 66% by afternoon. Salinities were successfully maintained between 28 %o and 34 %o by balancing tap water against evaporation which was about 8 to 12 cm per week. The pH remained between 7.2 and 9, the temperature between 28 and 35°C, and efficiencies of gross photosynthesis between 0.5 and 1.5 per cent of visible light incident on the pyrheliometer. Not all of the diurnal patterns were as expected from bay studies. Although the pH rose during the day, the iron concentration of millipore filtrates increased during the day (Fig. 12) , a reverse effect from that expected from considerations of pH effect on iron solubility. Phosphorus in the graphs for July 13-14 (Fig. 12) showed variation with little trend. The graphs for August 21-22 have day and night minima. The August 31 series (Fig. 13) had inorganic phosphate increasing during the day, in reverse from that expected from studies of Bruce and Hood ( 1959) for the bays. One finding of considerable significance for future pond work was the demonstration of continuous mixing without stratification in the larger pond under ordinary wind stresses of the Texas coast. By having straight walls and rounded corners, no consistent vertical temperature or oxygen differences developed. The water was observed to drift and roil slowly as it does in the bays when there is little wave action. The reaeration constant as computed from the graphs ranged from 0.4 to 1.1 g oxygen/m3/ hr for 100% deficit, a value less than that of strongly mixed open bays but more than in stratified ponds. Light penetration and bottom heating helped maintain daytime turnover. The General Marine Science class found constant vertical temperature patterns in a diurnal study July 6-7, 1961, measuring temperatures at 1, 5, 10, 20, and 30 cm depth. Dr. Reid Bryson and Dr. Robert Ragotzkie pointed out verbally that the diurnal measurements of temperature and salinity in the pond could be used as a net radiometer. As a sample, they computed from the temperature curve of the water on a clear day for July 7, 1961, an increase of heat content in the water from dawn to dusk of 300 calories per cm2, a heat loss due to evaporation of 128 cal/ cm2, and a heat loss through conduc­tion of 13 cal/cm2 for a total of 441 cal/cm2/day net radiation input. The total insolation received from pyrheliometer readings was 765 cal/cm2 • The hundreds of diurnal temperature curves taken in the bays in the past 5 years as part of diurnal oxygen studies are presumably usable for similar analysis. pH-C02 graphs were made along with oxygen on two days in the summer. Metabolic molar quotients were computed as the ratio of carbon to oxygen in Table 1. These values mainly show some confirmation of the oxygen method and carbon methods. These quotients fall within the ranges found in the prototype environments. Thus in many indices with which bay processes are measured, similar values were maintained by the grass pond system during the summer period. BLUE-GREEN ALGAL MAT PONDS In a week after seeding, the blue-green algae developed fresh green new mats over the bare sand between the transplanted mats so that there was a continuous carpet. A heavy population of corixid water bugs developed. Metabolic curves with an anaerobic nighttime phase with low redox potentials were observed just as in the environmental prototype. A vertical structure of filaments and black organic ooze was maintained like that analyzed by Sorensen and Conover (1962). In November, 1962, with the onset of cold weather, the blue-green algae disappeared and the heavy black ooze below the mats declined. Microscopic examination during the winter showed only diatoms. Then in late March, 1963, the ponds turned bright yellow as the blue-green algae again bloomed as a bottom carpet. Although salinities ranged from oligohaline to hypersaline, the water bugs were abundant in the water over the bottom throughout the summer, winter, and spring. In Figs. 14-16 are the diurnal properties observed in the blue-green algal mat pond which may be compared with those in the environmental prototype (Odum et al., 1963}. The low level of the water allowed the heat and metabolic reception of the sun's energy to be concentrated so that very wide daily ranges of temperature, oxygen, redox potential, and pH were observed (Fig. 14) as in the prototype. Salinity was initially 15 %o but increased to 20-30 %o by evaporation when the metabolic pattern was recorded in Fig. 14. Alkalinity ranged between 2.1 and 2.6 milliequivalents per liter. By July 22 when metabolism was again measured (Fig. 15) the salinity had reached 74.4 %o· These wide ranges precluded the development of many kinds of organisms. The persistence of these mats and metabolic patterns in these ponds through the summer confirmed the role of the shallow depth as a mechanism controlling biota. The role of the anaerobic nighttime phase in restricting consumers and thus favoring the deposition of organic matter suit­able for oil petrogenesis was proposed earlier (see abstract, Odum and Vick, 1962}. The feasibility of culturing the blue-green mat system in ponds and smaller micro­cosms has implications for experimental study of sedimentary diagenesis. The diurnal variations in potential and the significance of electrochemical power take off from this ecosystem is explored in a manuscript by Armstrong and Odum (1963). The comparison of metabolic rates computed for carbon are compared with those for oxygen in Fig. 14. As in the blue-green mat ecosystems in the bay prototypes, a very large molar metabolic quotient (COif0 2 ) developed. The discrepancy exists even after over-corrections are made for Winkler interference and reaeration. The discrepancies between carbon and oxygen were particularly large after dawn when it may be postulated that oxygen deficits accumulated in the mat during the low oxygen periods of the night were oxidized thus masking the gross photosynthesis. The metabolic patterns of carbon in Figs. 14 and 15 were not greatly asymmetrical and were similar to those in aerobic systems . . The record on August 5-7 in Fig. 16 indicates the rising salinity with evaporation during a two day period as well as the normal metabolic rise and fall of pH. With high pH values and carbonate equilibria shifted mainly toward the carbonate state, photo­ synthesis in this system is apparently operating directly on carbonate fractions as indi­ cated by the variation in alkalinity. The steady rise in salinity charted in Fig. 16 reflects the evaporation rate. DISCUSSION In these examples, control and morphometry, circulation, and seeding in ponds allowed Mat Pond Ju ly 3-4, 1962 0.17m 22 °/oo 9.0 8.0 Mg/ I oc 0 .3 0.2 -0.1 FIG. 14. Diurnal record of pH, oxygen concentration, temperature, and carbon and oxygen metabolic rates, July 3--4, 1962, in the blue-green mat pond. Oxygen rate was overcorrected for reaeration by using KG 1.5. 0 .200 Fie. 15. Diurnal record of pH, total carbon dioxide, and rate of carbon metabolism, July 22-23, in the blue-green mat pond. Alkalinity was 2.1 meq/l. Mat Pond Aug. 5-7, 1962 l l pH Alkalinity 3.0 ~ i.o.....-----+------+------+------4 Salinity 0/oo 27 25 23_0_0______~0~6---'--_.__.12~---_...~1~s~-----~oo HOURS FrG. 16. Diurnal record of pH, alkalinity, and salinity, August 5-7, 1962, in the blue-green mat pond. productive ecosystems to develop with many properties like those of the bay prototypes being simulated. Not all the properties and components were like the bays, however, as in the instances of rotifers in the reef ponds or the water-bugs in the blue-green mat ponds. The systems cultured were similar but not the same as the prototypes. Nighttime low oxygen conditions were developed according to the water depth and nutrient concentrations without contributions or organic pollution, especially when respiration exceeded photosynthesis following periods of high productivity. In very shallow waters, low nighttime oxygen tension was apparently a necessary consequence of appreciable productivity. Discrepancies between carbon and oxygen rates by these methods apparently exist even when potential artifacts such as Winkler interference and inadequate reaeration corrections are eliminated. In the shallow blue-green mat system photosynthetic oxidants apparently go for oxidation of system substances without appearing as dissolved oxygen so that the diurnal oxygen underestimates the metabolism as measured by carbon. A similar process may have been involved in the sequence in the triplicate ponds in which respiration seemed to be exceeding photosynthesis through much of the summer. Diver­sion of some plus charge "holes" in photosynthetic receptors into some processes other than relea~e of oxygen causes the P /R ratio to be too low and the assimilatory quotient to be too high. Whereas P /Rand AQ are objective parameters of the ecosystem, regard­less of the diversions of electrons or holes to other processes, the P /R and AQ under these conditions are representing only part of the basic oxidation and reduction processes driven by light. The circumstances resemble those in the Black Sea as studied by Kriss ( 1963). Considering all the pond experiments, metabolic rates were mostly less than 6 g oxygen per m2 per day without outside pumping energy and somewhat higher in the triplicate reef ponds with auxiliary power supplement through the pump. These values involve photosynthetic efficiencies 0.5 to 3% of visible energy received and were generally some­ what less than the best developed prototype bays. Considering the cost of marine field work, the pond method for experimental and replicated study of the bay prototypes is attractive for intensive controlled study of metabolism and marine biogeochemistry. For example, radiotracer experiments in ecosystems of known metabolism and populations can be safely followed in the pond systems and used to interpret bay phenomena with some justification. The pond systems were less diversified than the bay prototypes as expected due to their isolation from large population reservoirs. Total metabolism was also less than in some prototypes. Formulae for ecological engineering such as those tested in this study may be useful in channeling energies into particular food chains in ecosystem culture. Acknowledgments We are grateful for measurements and chemical assistance by Mr. John Meadows, John Ellison, Bill Gillespie, Frank Little, Millard L. Kelly, Richard A. Davis, Jr., Cathy Smith, Tommy Brayshaw, Mrs. Mary Ann Chilen Davis and Mrs. Barbara Beyers. Ponds were designed by Mr. William Ogletree, Marine Engineer, Corpus Christi, Texas. Dr. B. J. Copeland provided pictures and collaborated in measurements in Sep­ tember, 1962 and May, 1963. Dr. Patrick Parker and Miss Lorna McGough provided iron analyses and Mr. Ron Wilson organic matter determinations. Illustrations were done by Mrs. Pauline West. Literature Cited Beyers, R. J. 1962. Relationship between temperature and the metabolism of experimental ecosys­tems. Science 136, (3520): 980-982. Beyers, R. J. 1963a. The metabolism of twelve laboratory microecosystems. Ecol. Monogr. 33(4): 281-306. Beyers, R. J. 1963h. A characteristic diurnal metabolic pattern in balanced aquatic microcosms. Puhl. Inst. Mar. Sci. Univ. Tex. 9: 19-27. Beyers, R. J., J. Larimer, H. T. Odum, R. Parker, and N. Armstrong. 1963. Directions for the de­termination of changes in carbon dioxide concentration from changes in pH. Puhl. Inst. Mar. Sci. Univ. Tex. 9: 454-489. Beyers, R. J., and H. T. Odum. 1959. The use of carbon dioxide to construct pH curves for the meas· urement of productivity. Limnol. and Oceanogr. 4 ( 4) : 499-502. Bruce, H., and D. W. Hood, 1959. Diurnal inorganic phosphate variations in Texas Bays. Puhl. Inst. Mar. Sci. Univ. Texas. 6: 133-145. Collier, A. 1959. Some observations on the respiration of the American Oyster Crassostrea virginica (Gmelin). Puhl. Inst. Mar. Sci. Univ. Tex. 6: 92-108. · Hedgpeth, J. W. 1954. Bottom communities of the Gulf of Mexico in Gulf of Mexico, its origin, waters, and marine life. U.S. Fish. Bull. 55(89): 203-216. Hellier, J. R. 1962. Fish production and biomass studies in relation to photosynthesis in the Laguna Madre of Texas. Puhl. Inst. Mar. Sci. Univ. Tex. 8: 1-22. Kriss, A. E. 1963. Marine Microbiology (Deep Sea) transl. by J. M. Shewan and Z. Kahata. Oliver and Boyd, London, 536 p. Lewis, G. J., and E. D. Goldberg, 1954. Iron in marine waters. J. Mar. Res. 13: 183-187. Odum, H. T. 1962a. Man in the ecosystem. Proc. Lockwood Conference on the Suburban forest and ecology. Bull. Conn. Agr. Station. 652: 57-75. Odum, H. T. 1962b. The use of a network energy simulator to synthesize systems and develop analogous theory: the ecosystem example. Proc. Cullowhee Conference on Training in Biomathe­matics. p. 291-297 (p. 390). Odum, H. T., and C. M. Hoskin. 1957. Metabolism of a laboratory stream microcosm. Puhl. Inst. Mar. Sci. Univ. Tex. 4: 115-133. Odum, H. T., and C. M. Hoskin. 1958. Comparative studies of the metabolism of marine waters. Puhl. Inst. Mar. Sci. Univ. Tex. 5: 16-46. Odum, H. T. 1963. Productivity measurements in Texas turtle grass and the effects of dredging an intracoastal channel. Puhl. Inst. Mar. Sci. Univ. Tex. 9: 48-53. Odum, H. T., R. J. Beyers, and Neal Armstrong. 1963. Consequences of small storage capacity in nanoplankton pertinent to measurement of primary production in tropical waters. J. Mar. Res. 21(3): 191-198. Odum, H. T., and N. Vick. 1962. The paradox that film ecosystems are anaerobic basins. (abstract) p. 493 in Gorsline, D. S. Proc. First Natl. Coastal and Shallow Water Research Conference, Tallahassee, Florida, 897 p. Odum, H. T., and R. F. Wilson. 1962. Further studies on reaeration and metabolism of Texas Bays, 1958-1960. Puhl. Inst. Mar. Sci. Univ. Tex. 8: 23-55. Odum, H. T., R. Cuzon, R. J. Beyers, and C. Allhaugh. 1963. Diurnal metabolism, total phosphorus, Ohle anomaly, and zooplankton diversity of abnormal marine ecosystems of Texas. Puhl. Inst. Mar. Sci. Univ. Tex. 9: 404-454. Ohle, W. 1953. Die chemische, und die electrochemische Bestimmung des molecular ge!Osen 'Saver­stoffes der Binnengewasser. Mitteil. Int. Assoc. Theoret et appl. Limnolgie 3: 1-44. Parker, P. L., Ann Gibbs, and Robert Lawler. 1963. Cobalt, Iron, and Manganese in a Texas Bay. Puhl. Inst. Mar. Sci. Univ. Tex. 9: 28-33. Park, K., D. W. Hood, and H. T. Odum. 1958. Diurnal pH variation in Texas Bays, and its application to primary production estimation. Puhl. Inst. Mar. Sci. Univ. Tex. 5: 47-64. Sorensen, L. 0., and J. T. Conover. 1962 Notes on algal mat communities of Lyngbya con/ervoides (C. Agardh) Gomont. Puhl. Inst. Mar. Sci. Univ. Tex. 8: 61-74. Wilson, R. E. 1963. Studies on organic carbon in Aquatic Ecosystems. Ph.D. dissertation. The Uni­versity of Texas, 180 p. Wilson, R. E. 1961. Measurement of organic carbon in sea water. Limnol. and Oceanogr. 6, (3): 259-261, (1). Zwicker, B. M. G., and R. J. Robinson. 1944. The photometric determination of nitrate in sea water with a stychnidine reagent. J. Mar. Res. 5: 214-232. Diurnal Metabolism, Total Phosphorus, Ohle Anomaly, and Zooplankton Diversity of Abnormal Marine Ecosystems of Texas1 HowARD T. 0DuM2, RENE P. CuzoN DU REST 3, ROBERT J. BEYERS, AND CLYDE ALLBAUGH 4 Institute of Marine Science The University of Texas Port Aransas Abstract Diurnal patterns of metabolism, total phosphorus concentrations, Ohle oxidation-reduction anom­alies, and species diversities of zooplankton were studied in some abnormal marine ecosystems of Texas under influence of waste effluents. Diurnal measurements of oxygen and pH were made simul­taneously at several stations in each bay system. Metabolic computations were made by summing the similar curves from the several stations in a bay, by summing diurnal data from several strata in deeper waters, and by using Ohle corrections and oxygen electrodes to confirm oxygen patterns. Metabolic quotients (C02/02 ) were computed where both carbon dioxide and oxygen metabolic rates were obtained. Metabolic quotients ranged from 0.4 to 1.9. Some photosynthetic efficiencies were computed with pyrheliometer data. A bleedwater lagoon with a benthic blue-green algal mat ecosystem contained 26 to 876 ppb total phosphorus, little or no zooplankton, large and variable Ohle anomalies (0.3 to 2.8 ppm both oxidizing and reducing), a diurnal curve with nearly zero oxygen at night but super-saturation in daytime, a post sunrise oxygen deficit, a moderate efficiency 1 % to 3% of visible light energy received, and an excess of respiration over photosynthesis. In natural briny conditions of the Mexican Laguna Madre at 121%0, oxygen remained nearly zero through the day with little evidence of photosynthetic metabolism. A seafood waste system in Conn Brown Harbor at Aransas Pass, Texas maintained total phos­phorus 53-306 ppb, zooplankton species diversities 4-14 species per thousand individuals, large amplitudes of diurnal oxygen and pH curves, respiration in excess of photosynthesis, and photo­synthetic efficiencies of 0.8% to 3.8% of visible light energy received. The Brownsville Shrimp-boat channel with less concentration of wastes had 10 to 200 ppb total phosphorus and 8 to 18 species of zooplankton per thousand individuals. Ship channels at Houston and Corpus Christi receiving heavy influxes of wastes varied markedly depending on conditions of flushing with phosphorus ranging from 2 ppb to 1290 ppb, species diversities ranging from 1 to 11 species per thousand or no zooplankton, some diurnal metabolic curves of large amplitude but also some of little amplitude, some wide-ranging patchy conditions, large Ohle anomalies up to 7 ppm both oxidizing and reducing, large and variable pH fluctuations, and oxygen stratification with near anaerobic bottom conditions. Shallow bays receiving wastes from the ship channels and peripheral sources, Nueces Bay, Corpus Christi Bay, and Galveston Bay contained total phosphorus contents 2 to 2000 ppb, zooplankton species diversities 2 to 19 species per thousand, Ohle anomalies up to 1.4 ppm, and metabolic curves ranging from almost no metabolism to 60 g/m2 per day usually with respiration in excess of photo­synthesis, and patchy conditions in distribution of oxygen and pH with large ranges. Abnormal bays were usually but not exclusively higher in phosphorus, lower in diversity, more erratic in diurnal patterns, with larger Ohle anomalies, and had recognizably extreme diurnal meta­ 1 Supported by a grant from the U.S. Public Health Service, Division of Water Pollution Research, WP 00204-04. N.G. Vick was leader of field teams. 2 Present address: Puerto Rico Nuclear Center, Rio Piedras, P.R. 3 Present address: National Oceanographic Data Center, Washington, D.C. 4 Present address: Department of Biology, Texas A&M University, College Station, Texas. bolic patterns. A classification of diurnal patterns associated with waters receiving wastes included: (1) excess of photosynthesis over respiration (1 case); (2) excessive respiration with undersaturation continuously but with a photosynthetic pattern; (3) regular but amplified diurnal pattern; (4) toxic system with near saturated non-metabolic pattern; (5) wide ranging patchy condition in oxygen and pH properties; (6) stratified channel with reduced bottom waters; (7) diurnal deficit regime with nocturnal anaerobic curve and large daytime photosynthesis. Many of the Texas Bays in the 1960-1962 period were demonstrably affected by the wastes. The phosphorus data, Ohle anomaly measurements, the counts of zooplankton species diversity, photo­synthetic efficiencies, and diurnal curve characteristics were found to be sensitive means for indi­cating normal or abnormal conditions. Introduction Behind the beach line of Texas into a million and a half acres of shallow green bays, the expanding urban culture of coastal Texas is accelerating its rates of marine waste discharge. With little daily tide and relatively little exchange of water with the open Gulf, the contributions of the rivers, the Gulf tides, and the waste flows are stirred by the strong Texas winds to provide new regimes with corresponding changes in the ecological systems which result. What kinds of abnormal ecosystems are developing? How are these systems identified and contrasted with the previous ecological systems? How is the total metabolism and productivity affected? What sensitive indicator tech­niques are available for monitoring the areal extent of the system types? Considerable knowledge exists on the marine pollution of Texas bays mainly in a number of unpublished reports of the Texas Game and Fish Commission, the Texas Health Department, Philadelphia Academy of Sciences, Texas A. and M. Research Foundation, and many of the coastal industries. Fish kills in Offatts Bayou, a corner of Galveston Bay near Galveston, were described by Gunter (1942), and the dinoflagellate blooms and patchy oxygen patterns there were described by Connell and Cross (1950). Bacterial patterns related to wastes were traced by Oppenheimer, Travis and Woodfin ( 1961) for several bays. Detailed studies of biological and physical properties related to wastes were given by Chambers and Sparks (1959) and Hohn (1959) for the Houston Ship Channel. In a sequence of previous papers, the normal patterns of total photosynthesis, total respiration, and total phosphorus were presented for some Texas Bays relatively less affected by the urban waste flows (Odum and Hoskin, 1958; Park, Hood, and Odum, 1958; Bruce and Hood, 1959; and Odum and Wilson, 1962). These papers report the use of diurnal curve methods where the conditions of thorough mixing and shallow depth without much tidal transport or stratification are particularly favorable. It was also noted that such methods provided sensitive means for assay of abnormal regimes and their metabolism (Odum, 1960b; Copeland and Dorris, 1962). In this paper, these measurements are made in ecosystems of the Texas marine bays where waste flows are important. Effort was concentrated on 3 types of abnormal eco· systems and on some zones between the abnormal systems and normal systems where indices of ecosystem function were useful for delimiting the boundaries of influence between normal and abnormal types. The three main types of systems studied were as follows: I. Bleedwater-bluegreen system. A complex of diurnally oscillating aerobic and anaerobic conditions develops in very shallow marine bay waters receiving the bleed water wastes of oil drilling. The very hard waters, rich in nutrients and contaminated with some oil, combine to produce massive bluegreen algal mats and associated sulfur bac­terial phenomena such as red water. An example of this complex was studied in a lagoon three miles south of the Flour Bluff toll station on the west side of the Upper Laguna Madre of Texas (see Fig. 1). The natural brines of the Mexican Laguna Madre were studied for comparison. II. Seafood waste system. A complex of highly metabolic plankton waters develops where regular discharges of wastes from packing of shrimp and crabs are returned to the sea waters. Such a complex was studied in Conn Brown Harbor and Brownsville Ship Channel (see Figs. 2, 3 and 4). III. Composite ship channel waste system of an oil city. The multiple pollutions from refinery wastes, municipal wastes, and wastes from chemical processes related to the oil industry exist in the Houston Ship Channel which discharges into upper Galveston Bay (Figs. 5 and 6) and in the Corpus Christi Ship Channel which connects with Corpus Christi Bay (Fig. 7). These two composite waste systems, representing extreme concen­trations of waste in a marine environment, were studied and their influence on adjacent bays followed with the several methods. The Houston Ship Channel was diluted and flushed at irregular rates by the San Jacinto River into Galveston Bay as shown by Chambers and Sparks (1959) whereas the Corpus Christi Channel was discharged by exchange at its connection to Corpus Christi Bay without river flow and by steady pumping of channel water through the Central Power and Light Company cooling systems out into Nueces Bay, water being replaced from Corpus Christi Bay through the mouth of the channel. A complete map of the Houston Ship Channel and adjacent industrial plants is given in Chambers and Sparks ( 1959). Fie. 1. Corpus Christi Bay with adjoining smaller bays. Numbers indicate stations. Dashed lines indicate ship channels. Frc. 2. View of Conn Brown Harbor, Aransas Pass, Texas, location of sea-food waste discharge, Feb. 1, 1960; view from the east. 5 ,4,5, 10 . ' ' ' ' ' ' ' ' ' ' ' ~\ 13, 10, 17, 13 .. 86, .. .. . . 260,_1_!! . "V ,, ",, \ye~ .l ~.·~:·~:·.:.~:~·;·~:·~:·:·~···-'.·.. ,, ... " ' ' ' ' \\ 36,~ ",,,,,, ':,, I ""\\ " " \\,, . \\ I ' I: ! I I czd~_­\\~~ : 18, 15, 18, 11 Total Phosphorus mg/m3 1962 ~ January 17-18, 1961 Morch 10·14, June 20, 1961 August 15, --­ Species per 1,000 indivi duo Is Mor. 16, Apr. 13, Moy 23, June 7 Frc. 3. Distribution of variables at stations in and near Conn Brown Harbor, Aransas Pass, Texas. Diagram on the right depicts channel through Aransas Pass jetties. Methods The methods were extensions of those used in the studies of the normal bays cited with the addition of some new features. DIURNAL OXYGEN METABOLISM MEASUREMENTS The diurnal curve procedures set out in Odum and Hoskin (1958) were used with several changes. Generally, it was possible to run several concurrent stations making it Abnormal Marine Ecosystems of Texas "' g -0 ·;; ~30 0 0 0 ...: 20 ., c. "' -~ 10 ., c. Cf) 30 201--~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~--1 Tota I 200 µg/ I Jon. 21, 1961 lOO Aug. 28, 1961 FrG. 4. Distribution of variables in the Brownsville Ship Channel. Graphs and map drawn to horizontal scale. possible to provide more confidence about the representativeness of the curves used for computations. Instead of determining the diffusion constant from the diurnal curve on the basis of an assumption about respiration the process was reversed. The estimates of diffusion contant (k = 1 gm/m3 per 100% deficit) based on previous diurnal curve work in normal bays (Odum and Wilson, 1962) were used for diffusion corrections and the night-time respiration obtained by subtraction. Where interference was suspected with Winkler processes at low oxygen tension, some oxygen electrodes were also used. The Jarrel-Ash-Kanwisher portable battery apparatus was used to survey microenviron­ments in the bleedwater system. Recordings were made from a Maney-Okun (Maney and Westgarth, 1962) electrode operating in the field from portable generators. Most of 409 Upper Galveston Boy April 18-19, 1961 .·\• ~"'"" Stations F1G. 5. Distribution of variables in Upper Galveston Bay, April 18-19, 1961 including diurnal record of oxygen, pH, and derived quantities. the graphs were prepared from data taken by standard Winkler analysis corrected for interference with the Ohle anomaly procedure (Ohle, 1953). OHLE ANOMALY The Ohle procedure (Ohle, 1953) was used not only for a Winkler correction but also as a measure of oxidizing and reducing substances present that may be related to Houston Sh ip Channe l July 17-18, 1961 JO mg /I 5 mg / I o, San Jo cinto Monument (I) 8 4m i:~t:-~;:::~:;E; o, Baytown Refinery (2) 0 4Qr-~~~...-~~~-r-~~~...-~~~, 0 2 Sum 2x2m 4 x 4m 2 x 7m 1 x 9 m San Jacinio Monument 2 Baytown Refinery 3 Baytown Tunnel o-~~~-+-~~~--+-~~~--o~~~--o ' '" /> " \ \~ ,.;.ir' \ " )~ " \3,, \ // \ -­,' \ • _______/··••2 \.._____ _____ ··....·­----­---~ Surface T fc _/,./···--1~---------•••_____ 91-~~~~~~~~~~~~~~~--12 00 06 12 18 00 HOURS FIG. 6. Diurnal oxygen, pH, and temperature patterns at 3 stations in the Houston Ship Channel July 17-18, 1961. Four levels are given at each station and a rough calculation of the total oxygen in vertical column is made for the diurnal period. FIG. 7. Stations in Nueces Bay and in Corpus Christi Ship Harbor. waste distribution. The procedure is outlined in Table 1. A precise amount of the Ohle iodine-iodide reagent (1.0 ml) was added to duplicates so that any oxidizing or reducing that might take place abnormally in the Winkler process would presumably work on the added iodine or iodide. By leaving the manganous sulfate out of one set of duplicates, the contribution of dissolved oxygen to the final thiosulfate titration was eliminated. Subtracting the Ohle control from the Ohle plus oxygen titrations, provided an Ohle­Winkler analysis from which interference either of oxidizing or reducing nature had been removed. The Ohle anomaly was then calculated by subtracting this Ohle Winkler analysis from the regular Winkler analysis to obtain the amount of interference in mg/liter. Where the standard Winkler analysis was larger than the Ohle Winkler, the anomaly indicated oxidizing interference (plus); where the standard Winkler analysis was smaller than the Ohle Winkler, reducing interference (minus) was indicated. These anomalies were plotted on graphs and maps. TABLE 1 Ohle anomaly procedure Collect a half carbuoy of water; homogenize by swirling 3 minutes; siphon 6 duplicates into Winkler bottles. Add reagents as follows: Bottles 1 & 2 : Follow regular Winkler procedure. l Bottles 3 &4: Bottles 5 &6: Add Ohle iodine-iodide reagent; follow with regular Winkler procedure. Add Ohle iodine-iodide reagent; llSubtract t<> getIthe Ohle Winkler jSubtract to get fOhle anomaly J follow with regular Winkler procedure except omit manganous sulfate. Some oxygen graphs were corrected for interference by adding the Ohle anomaly. However, demonstrating that there are substances which are interfering with the Wink· !er process to the extent of the anomaly did not guarantee that oxygen was present. A zero oxygen analysis and evidence of reducing interference in the Ohle test may or may not indicate there is oxygen present. One cannot, therefore, make a blanket correction to oxygen curves in their anaerobic periods. DIURNAL pH-C02 METHODS The diurnal pH methods were improved versions of those reported in Beyers and Odum (1959) involving empirical pH versus C02 change graphs. Principal improve­ments are described in papers by Beyers ( 1963) and Beyers et al. ( 1963) . These include a revolving tonometer for equilibration of C02 water, convenient tables, and a computer program for calculations. Field data for pH were taken with a Model W and with zero­matic model Beckman meters operating from generators. DIURNAL CURVES IN STRATIFIED WATERS Most of the diurnal curve studies made in Texas marine waters have concerned shallow, continuously·mixing waters. However, some of the harbors and channels reported in this paper were either stratified, or had vertical mixing rates of the same order as the metabolic rates. Therefore, vertical gradients with exchanges from one stratum to another developed. McFarland and Prescott (1959) in their kelp study com­ puted diurnal changes in each of several arbitrary vertical layers. They used an inter­ layer diffusion constant derived in the same way that the reaeration constant is calcu­ lated from the rates of diurnal metabolism and saturation gradient. This method may require more data and more accuracy than is ordinarily available, but it does provide an independent way of obtaining the Austausch vertical turbulence coefficients. For these studies, however, the diurnal curve method was applied by first adding the oxygen con­ centrations of each layer to obtain a graph of the total oxygen per area. In some instances this involved adding the data from several stations. The rate of change was computed from this area-content graph. The reaeration constant was applied according to the surface saturation graph. Although continuous, vertical mixing was sometimes evident from the similarity of vertical temperature values, the area-sum procedure was generally used for the harbors and channels. With this method, the diffusion of oxygen from one layer to the other does not affect the sum for the vertical column. One of the observations made in the bays receiving wastes was the patchy character as observed in variation between duplicate samples and especially duplicate stations. The heterogeneity of the diurnal curves in the Nueces and Galveston Bays prevent any one curve from providing statistical evidence as to representativeness for metabolic calculations. Metabolic changes accumulated at one station drift to another, and show up as lags in the peaks of diurnal curves. If water moves from shallow to deep areas, over highly metabolic bottoms, through fish schools, or receives wastes, a very hetero· genous character may result. Just as the vertical layers were summed thus including oxygen that was transferred from one layer to another, so in large bays with drifting patches of water of different metabolic quality, it was possible to average to obtain a single oxygen graph for the bay. Although the pH-C02 method has some advantages for the study of large bays such as reliable recorder output, minimal reaeration effects, speed and minimal interference, the oxygen methods were more trustworthy because of the rough conditions of operation in small boats with spray, varying power in generators, and human errors where field assistants have limited experience with electronic equipment. Bottle experiments were made for comparison with the free water methods. Dark and light bottles were suspended at 0.5; 2.0; and 3.0 meters for six-hour periods. One series of radiocarbon measurements was made in bottles suspended for six-hour periods following the procedures summarized by Strickland (1960) . Bottles were filled from various levels with a submersible pump. ZooPLANKTON DIVERSITY The much used principle that abnormal new ecosystems affected by man's culture have less diversity of species was investigated for these marine bays using zooplankton counts and Gleason's ( 1922) species diversity index. Margalef's ( 1957, 1961) several measures of information content of species distributions were computed using a computer program written by Neal Armstrong of the Institute of Marine Science. It was found theoretically more suitable to compute the information content of the number of species only, a measure not computed by Margalef. Following Brillouin (1957) informational content of the number of circuits is the log of the number of circuits. Using each species as a biogeochemical food circuit (Odum, 1960a) , the informational content as a measure of organization of the ecosystem's species is the log of the number of species. It may be reasoned, consistent with the vast literature on species isolation mechanisms, that an ecosystem does provide means for insulation of its separate species circuits. Conse­quently, this species-information represents organization that has been specified, whereas much of the informational content that Margalef computed represents the uncertainty that has not been specified by organizing influences of the ecosystem. Thus, the informational content of the species as a measure of system organization may be expected to decrease as abnormal, newly-organizing, less-evolved system combi­nations resulting from wastes replace the older evolved systems. In this paper, the diversity index was compared to other symptoms of abnormal regimes such as unusual phosphorus and metabolic patterns. The reader who wishes may convert to bits by taking the logarithm. In the early phase of the investigation zooplankton collection was done with a Clark­Bumpus sampler fitted with a #2 net towed for 6 minutes. Insufficient numbers of plank­ton were obtained, however, partly because of the seasonal paucity of the plankton during the winter, and the relatively small (approximately 6 m3 ) volume of water filtered during each haul. To alleviate these difficulties a 1h m net with #12 mesh netting was used for the balance of the investigation. A #6 mesh net was used as a stand-by; in some instances the clogging resulting from the catch of numerous coelenterates was excessive with a fine mesh net. The hauls were all made at the surface for 4 minutes at approximately 2 knots. To minimize the clogging, the duration of the hauls with the 1h m net was reduced to 4 minutes, insead of 6 minutes, as the population densities increased in March. One thousand individual zooplankters were counted and the number of cumulative species were recorded for 10, 100, and 1000 individuals, thus abbreviating the semi­ log plot of species and individuals (Odum, Candon, and Komicker, 1960). Data were plotted as "species per thousand individuals", a number that may be com­pared for plankton, trees, microbes, etc. In all the bays and in the Gulf waters near the shore, the copepod Acartia tonsa was dominant throughout the year with 1 to 3500 individuals per m3• In a technique test, counts made at 4 hour intervals Dec. 28-29, 1961, at Port Aransas were 11, 8, 12, 10, 12 species per 1000. At the same time the number of plankters per cubic meter varied from 75 or less during daylight to 375 or more during darkness. TOTAL PHOSPHORUS Total phosphorus has long been used as a sensitive indicator of abnormal imbalances of respiration over photosynthesis or of abnormal wastes of many kinds. Its usefulness as a waste tracer in shallow marine bays in Florida was shown previously (Odum, 1953a). Total phosphorus procedures were designed to show larger differences in general nutrient level in the water, in the plankton, suspended clays, organic substances, etc., over the range from 2 to 2000 parts per billion. Water was collected and stored in glass stoppered 125 ml pyrex bottles previously cleaned with sulfuric acid and rinsed with distilled water. Water was emptied into 250 cc erlenmeyer flasks; the bottle walls were scrubbed with a rubber policeman and washed with perchloric acid which was then added to the flasks. Samples were digested by evaporation down to fuming condition with care that samples were removed before loss of white vapors. Then the salty paste residues were diluted with 100 cc of distilled water. The colorimetric analysis was made with the ammonium molybdate-stannous chloride procedures and compared with standards. A blanket 20% salt correction may be used, although data are reported without it here. The large magnitude and range of total phosphorus in these waters justified elimina­tion of procedures that would be used in the open sea for maximum accuracy such as field freezing of samples, making standards in phosphorus free sea water, high pressure autoclave digestion, and special glasses. New phosphorus data in this paper can be com­pared with earlier data (Odum and Wilson, 1962) . PYRHELIOMETER AND FooT CANDLE DATA Starting in 1961 a 50 junction Eppley pyrheliometer was mounted on the roof of the Institute of Marine Science. Recordings on a Yellow Springs Instrument amplifier­Rustrak recorder system were calibrated with a low resistance Weston precision micro­ammeter using the Eppley Company calibration relating current to g-cal/cm2 per hr. In the field the hand exposure meter was used: GM Golden Crown Meter with approxi­mate foot candle scale provided by the manufacturer with its incident light attachment. Under rough field circumstances the values must be regarded as very approximate. Where field measurements were within 25 miles of the Institute, it was considered feasible to compare pyrheliometer and foot candle records. With the cumulus types of clouds in summer, large local differences may be expected, but during frontal regimes with stratiform clouds, similarities may be expected. An RG-8 glass filter box was placed over the pyrheliometer to exclude the visible light, the difference being the visible light available for photosynthesis. This value varied with cloud type, but the 50% often quoted in the literature was about right for sunny days. Wind measurements were made in the field with a hand anemometer. Results In the following paragraphs are introduced diurnal graphs and aereal maps of proper­ties in the abnormal systems and nearby bays. I. BLEEDWATER-BLUEGREEN SYSTEM In Figs. 8 and 9 are presented diurnal data for a station in the bleedwater-bluegreen system on the edge of the Laguna Madre in 1961 at a time when benthic blue-green growths were heavy and the water was pink, and in 1962 when the pink color was less marked. In the very shallow, highly saline waters, there was a large diurnal range of conditions from nearly anaerobic to aerobic states with corresponding pH change due to carbon dioxide metabolism and other possible effects such as may have resulted from the changing oxidation conditions in the sulfur states. Whereas the carbon dioxide rate of change curve as inferred from pH indicated photosynthesis throughout the day, the oxygen curve for the first 3 hours after sunrise remained close to zero on the membrane mg / I ,..._--~oo 06 12 18 00 HOUR S HOU RS Fie. 8. Diurnal record of oxygen, pH, temperature, and light in the bleedwater lagoon containing bluegreen algal mats July 25-26, 1961. The position of stations is indicated in the sketch map. Bleed­water is entering at station 3; the lagoon discharges into the Laguna Madre to the left. Bleedwoter Blue-green Lagoon June 26, 1962 100 10,00 ~ s::; ;;-. Pyrhel iometer "'­ June 24 / pH E u ' 0 u "' mg/I corrected 5 \ uncorrected Money-Okun electrode / µa I I 0 .l...• .. Salinity 0/00601---.>.--­ f 50 0.2 40 3or-_r_ __,___ 1 20 "' JO ., oc 10 0 E oi--~~""""'~~~-t~~~-t-~~~~ 5 Wind 20 mph 0o~o,,..-~~0~6~~~........2~~~-,~8~~~00 1~ HOURS Frc. 9. Diurnal record of variables in the bleedwater lagoon June 26, 1962. Rates of change of oxygen are plotted with and without Ohle correction. Rates of change of carbon dioxide are plotted with negative values up as computed from the pH data. Metabolic quotients are plotted for the Ohle­corrected graphs. A winter radiation graph is included for comparison with sunny and cloudy summer days. electrode suggesting that an anaerobic deficit of reduced compounds were being oxidized by oxygen as fast as the oxygen was formed. Ohle anomalies were done a week later on July 3 (Table 2) at which time stations had up to 2.71 ppm of apparent oxygen decrease due to reducing substances. In contrast some stations further out in the bay had reversed anomalies indicating oxidizing effects. Also, quite variable results were found on July 16, 1962 (Table 2). Apparently the substances in the water at different places and times of day may have quite different effects on the Winkler process. A Kanwisher (Jarrel-Ash Co.) oxygen analyzer was carried over the lagoon by wading observers on a sunny day and the oxygen tensions explored in microenvironments. Near zero oxygen tensions were observed in the deeper waters, visibly turbid with pink bacterial activity, but as the probe was moved into the shallower water the oxygen rose immediately into the supersaturation range associated with the brilliant colored blue-green algal bottom mats. Maney-Okun electrode recordings TABLE 2 Ohle anomaly data 2 3 4 5 Ohio plus Ohle Corrected Anomaly Winkler Winkler only Winkler 2-3 1-4 Bleedwater-bluegreen system July 3, 1962 Station 1 4.46 5.15 10.99 10.05 4.80 10.52 5.15 1.29 3.11 7.41 -2.71 Station 2 0 0 0 1.56 1.64 1.60 0.50 0.20 0.35 1.25 -1.25 Station 3 5.61 6.52 9.91 (4.61 ?) 6.07 9.91 3.54 3.44 3.49 6.42 -0.35 Station 4 6.02 6.04 10.13 10.59 6.03 10.36 4.15 3.47 3.81 6.55 -0.52 Station 5 5.26 5.30 5.28 7.52 7.13 7.32 3.57 3.59 3.58 3.74 1.54 July 16, 1962, Dawn Station 1 0 0 0 0 Station 2 0 0 0 0 Station 3 4.46 4.54 4.50 7.35 7.54 7.43 4.34 3.98 4.16 3.27 1.23 Station 4 4.21 3.47 3.84 7.62 7.68 7.65 3.81 3.76 3.79 3.86 -0.02 Station 5 3.92 3.30 3.61 7.18 7.48 7.33 4.50 6.89 5.69 1.64 1.97 July 16, 1962, Sunset Station 1 0.99 1.03 1.02 4.85 4.26 4.55 2.10 0.87 1.48 3.07 -2.05 Station 2 0 0 0 0 ... Station 3 5.77 4.49 5.13 7.87 8.13 8.00 3.33 3.51 3.42 4.58 0.55 Station 4 5.35 5.30 5.32 8.90 8.89 8.90 3.06 2.96 3.01 5.88 -0.56 Station 5 5.54 5.73 12.35 9.30 5.64 10.82 3.43 3.43 3.43 7.39 -l.75 Houston Ship Channel August 22, 1962 Baytown Refinery 1000 Surface 3.52 3.52 3.52 6.98 6.98 2.16 2.04 2.10 4.88 -1.36 1910 Surface 3.36 3.48 3.42 7.10 7.58 7.32 2.98 2.67 2.82 4.50 -1.08 TABLE 2-Continued Ohle anomaly data Winkler 2 Ohle plus Winkler 3 Ohio only 4 Corrected Winkler 2-3 5 Anomaly 1-4 3.3m 3.43 2.30 2.86 6.60 5.70 6.15 2.74 2.57 2.65 3.50 -0.64 6.lm 0.48 1.34 0.91 4.56 5.23 4.89 2.78 2.74 2.76 2.13 -1.22 9.lm 1.96 0.59 1.27 3.86 4.50 4.18 2.91 2.81 2.86 1.32 -0.07 Galveston Bay August 22, 1962 Station 1 0755 6.06 5.30 5.63 9.12 8.92 9.02 3.49 3.55 3.52 5.50 0.10 1710 8.55 8.64 12.67 12.67 8.59 12.67 3.50 3.50 9.17 -0.58 Station 2 0820 5.59 5.78 5.69 9.60 9.90 9.65 3.56 3.79 3.67 5.98 -0.29 1730 8.05 7.98 12.50 12.85 8.01 12.27 3.31 3.17 3.24 9.03 -1.02 Station 3 0840 5.59 5.53 5.56 9.70 9.60 9.65 3.60 3.71 3.65 6.00 -0.44 1750 7.06 6.72 11.52 10.56 6.89 10.55 3.36 3.36 7.19 -0.30 Station 4 1810 7.74 7.79 11.25 11.60 7.76 11.42 3.46 3.07 3.52 7.90 -0.14 Station 5 0925 10.55 7.10 10.71 10.93 8.82 10.82 2.82 3.23 3.02 7.80 1.02 1835 7.60 7.82 11.39 11.38 7.71 11.38 3.25 3.15 3.20 8.18 -0.47 Station 7 1030 4.66 4.84 4.75 8.60 8.45 8.52 2.91 2.95 2.93 5.59 -0.84 2010 4.85 4.85 4.85 8.65 9.00 8.82 2.91 2.91 2.91 5.91 -1.06 Nueces Bay October 1-6, 1960 Station l 7.29 7.22 7.27 8.81 8.74 8.78 2.06 1.88 1.97 6.81 0.46 Station 2 8.23 8.19 8.21 9.66 9.61 9.63 2.00 1.42 1.71 7.92 0.29 TABLE 2-Continued Ohle anomaly data 2 3 4 5 Obie plus Ohle Corrected Anomaly Winkler Winkler only Winkler 2-3 1-4 Station 2b 10.24 11.52 2.89 10.32 11.38 2.07 10.28 11.45 2.48 8.97 1.31 Station 3 6.19 9.78 3.04 7.31 9.76 3.12 6.75 9.77 3.08 6.69 0.06 Station 4 6.38 8.22 2.19 6.58 8.32 2.11 6.48 8.27 2.15 6.12 0.36 Station 6 7.57 9.80 3.10 7.55 9.90 3.20 7.56 9.85 3.15 6.70 0.86 Station 7 7.55 10.30 3.17 7.66 10.27 3.19 7.61 10.28 3.18 7.10 0.51 Corpus Christi Bay Station 7 5.7 6.8 0.75 5.4 6.8 0.70 5.55 6.8 0.72 6.06 -0.45 Station 8 6.4 7.0 0.8 6.4 7.0 0.7 6.4 7.0 0.75 6.25 0.15 Station 9 6.5 6.8 0.6 6.8 7.4 0.6 6.65 7.0 0.6 6.4 0.25 Station 10 6.2 7.3 0.6 6.1 7.0 0.6 6.15 7.20 0.6 6.60 0.45 Station 11 6.0 4.8 0.4 6.1 6.6 0.8 6.0 5.7 0.85 4.85 1.15 Corpus Christi Ship Channel September 29, 1960 Station 1 Bay 6.65 9.12 2.51 6.63 9.07 2.72 6.64 9.10 2.61 6.59 0.05 Station 2 Corpus Christi 4.17 6.97 2.10 Turning Basin 4.57 5.32 2.08 4.37 6.14 2.09 4.05 0.37 Station 3 Avery Basin 4.36 6.58 2.26 4.22 6.54 2.60 4.29 6.56 2.38 4.18 0.10 Station 4 Tule Basin 2.18 4.20 0.88 2.29 4.40 0.81 2.23 4.30 0.84 3.46 -1.23 Station 5 Viola Basin 0.44 2.81 1.73 0.53 2.81 1.80 0.49 2.81 l.i8 1.03 -0.50 Corpus Christi Harbor July 21-22, 1962 Waters were not homogenized first in this series. Viola Basin (Station 5) 0530 Surface 5.43 7.68 6.98 6.15 6.14 9.41 5.79 6.91 8.14 -1.23 7.02 Abnormal Marine Ecosystems of Texas TABLE 2-Continued Ohle anomaly data 2 3 4 5 Ohle plus Ohle Corrected Anomaly Winkler Winkler only Winkler 2-3 1-4 2.8m 7.22 6.18 6.70 9.27 8.44 8.80 6.18 7.79 6.39 2.41 4.29 5.7m 3.65 6.90 5.28 2.97 5.57 4.27 3.82 6.04 4.93 -0.66 5.94 9.5m 5.19 0 2.60 5.23 6.11 5.68 0 0 0 5.68 -3.08 2000 Surface 4.86 3.72 4.29 7.91 9.66 8.79 9.26 5.35 7.31 1.48 2.81 2.8m 5.61 2.72 11.16 8.58 4.17 9.87 3.96 4.08 4.02 5.85 -1.68 5.7m 6.44 6.21 10.01 9.93 6.33 9.97 6.21 4.61 5.41 4.56 1.77 9.5m 2.64 8.74 5.30 10.77 5.67 8.04 7.22 3.66 5.44 2.60 3.07 Chemical Basin (Station 3b) 0615 7.87 3.98 5.43 6.56 5.84 6.20 5.84 4.65 5.25 0.95 4.48 2045 0 0 0 4.13 6.34 5.24 2.46 2.46 2.78 -2.78 Main Basin (Station 2) 0647 6.64 5.24 5.94 9.78 5.48 7.58 4.59 6.69 6.09 1.49 4.45 2131 6.82 12.90 5.76 8.52 11.70 7.01 7.67 12.30 6.39 Corpus Christi Bay (Station 1 in Fig. 7) 0722 11.55 8.98 10.97 8.08 12.58 9.97 9.81 10.78 10.47 5.91 0.31 1.76 9.50 1745 7.86 10.47 10.72 7.86 10.59 4.95 4.78 4.86 5.73 2.13 Conn Brown Harbor July 10-11, 1962 0605 7.00 10.68 4.56 6.12 0.88 1035 9.95 12.97 3.82 9.5 0.80 were also obtained which indicated that a near zero oxygen tension was in the water during the night and morning hours. From the molar ratio of carbon and oxygen changes, assimilatory quotients were computed for each hour. The action of the anaerobic system in putting oxygen and carbon-dioxide changes out of phase and in masking the oxygen production, produced very different quotients over a short time period (Fig. 9) than those normally found in an aerobic ecosystem (Beyers, 1963), or in single kinds of metabolic processes. If the rate of change graph for oxygen is plotted without any correction a very large photosynthetic quotient results (3 to 30 moles C02/ mole oxygen, see Fig. 9). The Mancy­Okun electrode did not show any oxygen getting through the membrane until late in the morning, but the Ohle analyses implied that substances were present in the water capable of interfering with the Winkler test. In the rate graphs of Fig. 9, an Ohle correction was applied even though there was no assurance that it should be applied before oxygen appears in the Winklers. For the purpose of computing rate of oxygen metabolism, the Ohle correction may be considered as "negative oxygen" during the period between sunrise and the time of appearance of oxygen in the regular Winkler. The reduced substances which tend to reduce oxygen as fast as it is formed may also provide an Ohle reducing anomaly. In Fig. 9, the adding of the Ohle average anomaly corrects the Winklers upward and con­verts the negative oxygen to fictitious positive oxygen for the purpose of computing the rate of change graph for oxygen metabolism. The resulting graph is plotted and the molar ratio of C02/ 0 2 becomes more like that expected from photosynthesis and respira­tory metabolism. The course of respiration rate of oxygen varied from a minimum before dawn and a maximum after sunset when oxygen tensions were still high. Respiration during the afternoon was presumably high since oxygen tensions were highest and recent photo­synthesis had accumulated labile organic matter. Whether one makes special computations like that in Fig. 9 or not, it is certain that the metabolism of carbon dioxide and oxygen are not concurrent in systems with night­time anaerobic phases. Respiratory and photosynthetic quotients over short periods of time may take a wide range of values. With parts of the shallow system storing reduced substances as oxygen deficits that are made up later in the day, there is a tendency for carbon metabolic values to be higher and more representative of the total biological metabolism of organic matter. The high AQ and RQ values obtained in other studies (Park et al., 1958; Wilson, 1963) may reflect these processes of delayed oxygen respira­tion and asymmetric carbon and oxygen processes in various degrees. Before dawn, the oxygen tensions were close to zero, but the system was not anaerobic in its upper layer and the blue-green algal mat was not operating without oxygen, for there was a steady reaeration influx. The graphs when corrected for the diffusion using the constant from other shallow bays show a considerable respiration (Fig. 9). The inflowing briny bleedwaters (station 3, Fig. 8) and the lagoon system were high in phosphorus (Table 3 and Fig. 8). These data indicate phosphorus levels much higher than in the Upper Laguna Madre (Odum and Wilson, 1962) into which the bleedwater lagoon drains. Phosphorus in another bleedwater pit near Ingleside July 11, 1961, was 206 ppb. MEXICAN LAGUNA MADRE-A NATURAL BRINEWATER For comparison with the bleedwater-bluegreen abnormal system produced by hot saline bleedwaters discharging into the Texas Laguna Madre, measurements were also made in similar depth in the Laguna Madre of Mexico where briny conditions are pro­duced by the natural climatic conditions. Graphs of diurnal oxygen are given for two stations and two seasons in Fig. 10 as obtained by Mr. Norman Vick, Mr. Robert Lawler, and Dr. Henry Hildebrand from the Mexican Laguna. The waters of La Capia at 121%0 on May 10, 1961 had no appreciable Ohle inter­ference. Winklers were zero; Winklers plus Ohle reagent 0.98; 0.92; Ohle without manganous inons was 0.95; 0.98. pH ranged from 7.5 to 7.8 without much pattern in the diurnal record. Apparently the very high salinities, 50 to 121%0 , favor nearly anaerobic conditions. Mexican Laguna Madre HOURS Fie. 10. Diurnal records of oxygen and temperature from the Laguna Madre of Mexico May 12­13, 1%1 {Data taken by N. Vick, R. Lawler, and H. Hildebrand) and Oct. 20-21, 1961 (Data taken by R. S. Jones) . Brines haYe a saturation oxygen tension as low as 1 mg/ liter. With the exclusion of many normal animals and other consumers, organic matter added by streams or by photosynthesis can develop high concentrations with water evaporation favoring some microbial decomposition. Some photosynthesis or photochemical liberation of oxygen was observable, but unlike the bleedwater lagoon total metabolism was small. Also given in Fi11;. 10 is a diurnal oxygen graph further south at Carvajal opposite the eighth Pass when salinities were 50.4%0• Although no more saline than the very fertile water of the Texas upper Laguna, the graph in Fig. 10 indicates a very small metabolic amplitude (P, 2.0 g/ m2 per day; R, 1.2 g/m2 per day). Waters were very turbid with suspended clays. Total phosphorus values in the hypersaline Mexican Laguna Madre, May 11-13, 1961, were relatively high (Table 3). TABLE 3 Total phosphorus for abnormal marine systems Location Date Station Total phosphorus in ppb Bleedwater-bluegreen system July 25, 1961 Mexican Laguna Madre May 11, 1961 May 13, 1961 Oct. 21, 1961 Seafood Waste System, Conn Brown Harbor March 10-14, 1961 June 20, 1961 Aug. 15, 1961 Lower Galveston Bay July 15-19, 1961 Upper Galveston Bay April 18-19, 1961 Corpus Christi Harbor Jan.9,1961 March 6, 1961 March 20, 1961 April 22, 1961 May 22, 1961 1 2 3 Los Flores La Capia Los Ciciones Arroyo El Tigre Brackish water arroyo Arroyo Del Gomeno Arroyo La Seca Los Flores La Capia Los Ciciones Brackish water arroyo Carvajal 1 2 3 1 2 3 1 2 3 1 2 5 6 7 8 9 10 11 12 1 2 3 4 5 2 3 4 5 2 2 2 2 142, 124, lll, 101 112, 32, 26, 41 378, 778,543,876 62, 62 127, 119 18, 20 78, 76 63,64 496,500 195,191 180, 186 59,57 98, 95 471 34 86 110 98 260 88 53 189 151 87 494,500 1116, 1302 2000+ 1222, 1295 830,890 568,569 431,488 487,497 385, 346 298, 345 215 8 178,315 4, 19 112 1000, 213 273 252 296 104, 106, 114, 108 119, 119 176,27 219,280,329,339 TABLE 3-Continued Total phosphorus for abnormal marine systems Location Date Station Total phosphorus in ppb June 12-13, 1961 2 214,157 3 3B0,325 4 364,372 5 312 Aug. B, 1961 1 2 170 161 3 146 5 2B3 Nueces Bay March 3, 1961 1 2 9, 6, 10 64,150,155 3 29,144, 14B 6 97,4 Aug. 3, 1961 1 2 126, 132 136,120 3 9B, 114 5 92, 110 6 llB, 115 Corpus Christi Bay March 6, 1961 BB 9 B, B, 11 96,97,103 10 113, 114 11 56,57,19,20 March 20, 1961 7 B6,BB,162 B 6, 14 9 7B,l30 10 74, 75 April 22, 1961 7 BB 175, 69 17,27 9 B,4 11 59,3 May 22, 1961 1 13B, 12B 2 142,144 3 15B,157 4 184 7 506,524 BB 306,329 9 230,232 10 22B,220 11 134, 140 Aug. B, 1961 1 74,64,12B 2 63, 7B,B4,100 3 66,66,124 4 70, 61, 17B, 151 5 61,39,52, 7B 7 299,26B B 20B,2B4 BB 151,141 9 170,152 10 229, 112 II. SEAFOOD wASTE SYSTEMS Conn Brown Harbor, Aransas Pass, Texas In Figs. 3 and 11-18 are presented maps of station data and diurnal curves for Conn Brown Harbor, Aransas Pass, Texas, including three stations, different seasons, and different levels. The basin was artificially produced by a spoil bank formed from dredg­ing (Fig. 2) and lined with shrimp boat docks and food processing plants. Fifty to 400 shrimp boats were present in the basin and refuse from crab and shrimp loading and 12. 10. 8. MO/ L 6. 4. 2. 0. a 06 12 18 24 TIME ELAPSED, MINUTES Frc. 11. Dual Channel recorder trace of a Maney-Okun electrode for oxygen and a Beckman Model W pH meter, both operating on a pumped stream of water in a moving small boat in Conn Brown Harbor during the afternoon, Dec. 3, 1961. 14. 06 12 18 24 TIME ELAPSED, MINUTES Frc. 12. Comparison of recorder traces of oxygen with the Maney-Okun electrode during the after­noon and later at night after vertical surface cooling had produced mixing. packing were dumped into the water, which was 3 meters deep. Water exchange occurred through the channel entrance at the south end by means of wind and tide in­duced water levels varying about 0.3 m per day. Appreciable stirring and mixing of water levels was observed in the wake of the many shrimp trawlers which had draughts between 1 and 2.5 m. At times the basin was mixed fairly well vertically and horizontally as indicated by a comparison of oxygen and temperature data from several levels and stations IFig.15) . At other times some temporary vertical stratification was observed in the distribution of properties (Fig. 18), and some horizontal differences developed from one end of the basin to the other (Figs. 16 and 17). Variations of oxygen and carbon dioxide concen­trations over short distances were indicated in the recorder traces of the Maney-Okun oxygen electrode and the Beckman pH meter (Figs. 11-13). Figure 11 for the daytime showed partial thermal stratification with patchy patterns of waste and heterogenous pH December 3, 1961 0400 HOURS HOURS Fie. 14. Diurnal record of oxygen at three stations and three depths in Conn Brown Harbor, January 18, 1961. Data on temperature, light, and the sum of the 9 oxygen curves are plotted. Conn Brown Harbor March 10-11, 1961 O/o mph g/m2 \ .le Pyrheliometer (visible 53% 297g col/day) g/m7'hr -..­ 8 0 "' oc HOURS Fie. 15. Diurnal record of wind, light, temperature and oxygen, in Conn Brown Harbor March 10-11, 1961. The sum of the 9 oxygen curves is plotted and used to determine the rate of change. Diffusion corrections for reaeration are made according to two assumptions using the percent satura­tion curve of the 3 surface curves. metabolism, whereas at night with cooling at the surface there was better mixing of the basin water (Fig. 12). The dominant role of metabolism in causing patchy variation in properties was indicated by the correlation of pH and oxygen in Fig. 11. The under-saturated condition of the waters (Figs. 14-17) indicated that the basin often maintained a higher respiration than photosynthesis (see results of metabolism computations in Table 4). At other times (Fig. 18) photosynthesis equaled respiration and diurnal curves were normal although with more amplitude than in less disturbed bays of similar depth, such as Corpus Christi Bay. Only on June 20-21, 1961 (Fig. 16) was metabolism small with irregular patterns of oxygen during the day. Efficiency of utilization of sunlight on this day was only 0.8% of visible energy received. The highest rate of gross photosynthesis, measured on July 10-11, 1962, was 42 g oxygen per m2 per day, with a corresponding efficiency in conversion of visible light energy at 3.8%. This value is as high as that observed in the undisturbed turtle grass beds outside the basin in Redfish Bay (Odum, 1963). Conn Brown Harbor June 20-21, 1961 22 %0 30.------..-----..-----..-------. 0 0 00 06 12 18 00 00 06 12 18 00 HO URS HOU RS FIG. 16. Diurnal record of oxygen, light, and temperature on a clear day June 20-21, 1961. The sum of the oxygen data is also plotted for the basin. Conn Brown Harbor August 15-16, 1961 Salinity 34 %0 o, al / mg I I a> / 61f / /J!>/ .r" ro-' '',,Jl _,/ tl T 33 oc 32 _.1··· <__ 31 30::~> 2900 06 12 HO URS 18 00 ~80 ::I 0 Nueces Bay J uly 30-31, 1959 1 0.25 15.2 28-37 2.7 2.2 .... ;;· <'I> July 16-17, 1960 2 0.45 34.6 29-33 9.2 4.3 i:., Oct. 5-6, 1960, 6 0.5 31-36 24-29 6.6 9.0 ~ 0 Nov. 1-2, 1960, 6 station mean 6 1.0 0.6-0.8 20-23 11.7 14.4 "'~ June 26-27, 1961 4 Aug. 3-4, 1961 5 Seafood Waste System, Conn Brown Harbor Jan. 17-18, 1961 3 0.92 0.78 3.0 8-26 13-18 7.4 27-30 27-32 14-15 0.5 4.7 4.0 3.2 7.5 s.o 0.05 ~ <'I> ;:! "' 0- March 10-11, 1961 Ju ne 8-9, 1961 3 3 3.0 3.0 27-30 21.0 17-20 28-29 15.0 15.0 17.0 17.0 2.0 2.1 '"-3 <'I> J une 20-21, 1961 Aug. 15-16, 1961 3 3 3.0 3.0 22.0 34.0 27-29 30-32 8.0 18.0 12.0 23.0 0.8 ~ ~ July 10-11 , 1962 3 3.0 33.0 29-33 42.0 35.0 40.0 48.0 0.7 LO 3.8 Corpus Christi Bay May 24-25, 1961 5 4.0 25-28 24-27 21.6 48.0 Dec. 28-29, 1961 4 4.0 12-15 26-27 1.3 1.3 June 19-20, 1961 5 4.0 25-27 27-29 14.0 27.0 1.9 *Inflowing hot bleedwaler station. t Possible C02 diffusion of importance. t Elttciency of p;ross photosynthesis computed as 4 KCal per gram of oxygen product ion oul pul and 50o/t) of pyrheliomcter re<'ords taken as available input. .... Nl '° In the series taken July 10-11, 1962 (Fig. 18) a comparison was made between the oxygen and radiocarbon bottle methods for measuring production and the diurnal free­water oxygen and pH methods in the highly productive plankton-type system existing at that time. Per area, daily gross production in free water was 1.3 moles for oxygen and 0.9 moles for carbon dioxide. In bottles oxygen production was 0.47 moles while radiocarbon fixation was about 1.4 moles, although bottles were variable. Examinations of the plankton at this time indicated a dominant phytoplankton of small green flagel­lates and minute diatoms. The zooplankton was dominated by Acartia tonsa., a species of Olithona, and pelecypod larvae. In March, 1962, the zooplankton contained mainly Acartia tonsa, Centropages, barnacle larvae and zoeae larvae. In Fig. 3 and Table 3 are given total phosphorus analyses (mean of paired samples) for Conn Brown Harbor and adjacent waters. High phosphorus values (averaging 143 ppb) were found in the harbor as compared to the outside waters (49 ppb) over the turtle grass beds where most of the nutrients of the ecosystem were bound into benthic components. The zooplankton species diversity of the outside bay waters (Fig. 3) averaging 14 species per 1000 individuals decreased to about 6 species per 1000 in the north end of the harbor. BROWNSVILLE CHANNEL Shown in Fig. 4 are data for the Brownsville shrimpboat channel which extends from the open Gulf westward through jetties, the Lower Laguna Madre of Texas, and through a dredged 3--4 m channel to the city of Brownsville. In depth, in aspects of restricted circulation, and in frequency of shrimp boats, this channel resembles Conn Brown TABLE 5 Light and dark bottle measurements for oxygen* in Conn Brown Harbor based on triplicates, g/m3 P gross (L-D) R (l·D) I D L D 0 .£: ;;­ 5so ' 0 u oL--~~..::....r.~~~.....i.~~~.::t::==-~~~ "' 00 06 12 18 00 HOURS HOURS Frc. 26. Diurnal records of variables at several stations in Nueces Bay Aug. 3-4, 1961 and June 26-27' 1961. When tested October 1-6, 1960, with the exception of station 2B near effluents, the Ohle anomaly in Nueces Bay was small and oxidizing (Table 2). Total phosphorus values obtained in Nueces Bay were moderately high (Table 3 and Fig. 7). On July 5, 1961 in the Nueces River at the Route 77 Bridge, 529 and 166 ppb were found. Corpus Christi Bay · The waste waters entering the Corpus Christi Harbor and Nueces Bay are exchanged HOURS Frc. 27. Diurnal record of oxygen and pH at two stations on the Nueces River July 5-6, 1961. with the western end of Corpus Christi Bay, a well mixed body. 3 to 4 m deep (Fig. 1). Wastes were also entering from aluminum and oil drilling industries on the north side. On the south side treated wastes from municipal effiuents were entering indirectly through Oso Bay and from the Naval Air Station. In a hydrographic survey, Hood (1953) indicated the land-locked properties of Corpus Christi Bay and the small tidal exchange with the Gulf. At that time he warned of the infrequent flushing and conditions favoring accumulation of wastes. Diurnal curves of oxygen, pH and related variables are given in Fig. 28-31 for 11 stations (see Fig. 1). Stations 1-5 were taken from a launch making a circle every 3 to 5 hours. Station 6 was in the La Quinta Ship Channel 10 m deep leading to the Reynolds Aluminum Plant. Stations 7-11 were at the end of long fishing piers and sampled from ~hore. Where agreement existed among stations the mean metabolism of the bay was calculated (Table 4). In the data for Oct. 13-14, 1960, boat stations may be compared with pier stations; temperatures, salinities, range of oxygen values, and dispersion of oxygen data are similar. However, an examination of single diurnal curves indicates greater irregu­larity and deviation from the regular diurnal curve in the pier stations as might be expected from water moving along the shores over some plant beds, receiving wastes, and less mixed. The La Quinta Channel (station 6) was somewhat stratified with little Corpus Christi Bay Oct. 13-14, 1960 Fie. 28. Diurnal record of variables at stations in Corpus Chrsiti Bay, Oct. 13-14, 1960. oxygen at the bottom, but the diurnal rise and fall in oxygen was observed at all depths indicating a high productivity per surface area. On Dec. 28-29 (Fig. 29), with relatively little incoming insolation indicated, oxygen values were very uniform and the diurnal swing with photosynthesis was hardly detect­able. The uniformity of the salinities indicates the well mixed condition. The species diversity counts in zooplankton expressed in species per thousand individ­uals counted were graphed in Fig. 32. This plot runs from the much polluted waters of Viola Basin, through Corpus Christi Bay to the inlet at Port Aransas, and 25 miles into the open Gulf. Species diversity ranged between 2 and 25 species per thousand. The two days in May and June (Fig. 30) represent a contrast to the winter condition in Fig. 29. Diurnal curves of photosynthesis were clearly recognizable and agreement between stations was good. The mean curves were used to calculate a single rate of change curve for the whole bay on the two dates. In both, respiration was exceeding photosynthesis. Although incoming radiation was similarly large in both instances, photosynthesis and respiration were almost twice as great in the May data from boat stations. In these data the agreement among oxygen samples over the large bay was good and quite in contrast to the wide ranging patterns in Galveston Bay (Figs. 19 and 20). Corpus Christi Bay Dec. 28-29, 1961 26-27 %0 Boat Stations 10.------.---"-T"----.---~ ~--~---~---......-----. Maney-Okun electrode 20 6.,,,,,;::::;2~~~~~~~...=-;;::~-~-;~-~ · -7.=......--...7-· .. mg/I µa ----­ ._·:.·· 0 5 Mean I 0/ oo 26.2 2 26 .6 3 26 . 3 4 26. 3 oc 10,00 0 pH Mean 8.5 "' Cl> "O ;3 c: 8.3 .·········· I 0 u ·... /-~:.-.::... 0 2' if 8 .1...._ ____,,____._____._____, 0 00 06 12 18 00 00 06 12 18 00 HOURS HOURS Fie. 29. Diurnal record of variables in Corpus Christi Bay, Dec. 2S--29, 1961. The heavy line is the mean of the curves. On August 9-10, 1961, at four shore stations, a pattern of irregular variation with little consistent diurnal variation was found both in oxygen and pH. Photosynthetic metabolism was small and hardly demonstrable. Phosphorus in Oso Bay, which receives treated municipal wastes, in ppb for July 11, 1961, were 394, 2, 455, 480, 64, 66, 173, and 168; and for March 6, 1961, 71 ppb. During 1961 the total phosphorus in the bay varied considerably (Table 3 and Fig. 1). For example, values were relatively lower on April 22, whereas May 22 values were much higher. The group of boat stations (stations 1-5 in Fig. 1) possessed lower phos­phorus content more like that of Gulf water from Port Aransas as compared with samples from the peripheral pier stations (stations 7-11). Phosphorus levels were very high for both May 22 and August 8 whereas the metabolic patterns for these days (Figs. 30 and 31) were very different. The August graphs indicated little metabolism in spite of the high nutrient level. Levels in March were much lower following the winter season. In winter the frequent passage of northers drops the outside Gulf tidal level as much as two feet for several days. The low tide permits the Corpus Bay system to flush out an appreciable part of its water and then to replace it with new Gulf water when the winds swing to the south and east on the reverse flow of passing cyclonic systems. Values in the mouth of Corpus Christi Harbor during 1961 were generally similar to those just outside in Corpus Christi Bay. This is consistent with the usual flow inward into the harbor mouth, driven by the large cooling flows of the industries pumping northward into Nueces Bay. Data from Less Disturbed Bays In San Antonio Bay, a low salinity bay fed by the Guadalupe River, March 3, 1962, ~-c;. --'Corpus Christi Bay_______________ HOURS HOURS Frc. 30. Diurnal record of variables in Corpus Christi Bay, May 24--25, 1961 and June 19-20, 1961. The heavy line is the mean of the curves. diversities were 1 species per thousand. On June 12, 1962, data indicated 8, 6, 5, 6, and 7 species per thousand. Total phosphorus in the Guadalupe River on May 28, 1961, was 228 ppb. In the Laguna Madre of Texas on May 8, 1952, diversity measurements were made from Port Aransas to ·Brownsville as follows: Values in Corpus Christi Bay were 19, 15, and 15 per thousand; in the hypersaline. region in upper Laguna Madre, values were 12, 9, 11, 9, 11, and 10; in the region of the land-cut south of Baffin Bay, values found were 9, 12, and 10; in the lower Laguna Madre, values were 13, 13, 12, 7, 10, and 10. These data are similar to those in the Brownsville Shrimp-boat channel (Fig. 4). In August 1960 the upper Laguna Madre had total phosphorus values of 43, 47, 36, 37, and 33 ppb, slightly lower than the 1957 data ( 40 to 130 ppb). Corpus Christi Bay August 9-10, 1961 Pier Stations 10.-----,,...-----.---.......-----. ~---.......----.----T'"-"----. Mean mg/I oc 5 0 Fie. 31. Diurnal record of variables in Corpus Christi Bay from pier stations Aug. 9-10, 1961. The heavy line is the mean of the curves. 10 27.2 9 27.7 8 30.5 7 31.6 HOURS 0 0 Q ., ~ 10 .. c. ., .." c. en ----------------50 Miles---------------­ F1c. 32. Species diversities in zooplankton (species per thousand individuals) from the western end of Corpus Christi Harbor to a station 25 miles out on the shelf of the Gulf of Mexico off Port Aransas. (See Map in Figure 1.) For Aransas Bay, values for species diversity were obtained from the water of the Gulf at Port Aransas jetties to the low salinity waters of Copano Bay. Diversities in Aransas Bay (see top of Fig. 1) ranged from 4 to 23 species per thousand. During the winter, as on Nov. 27, 1961, Dec. 8, 1961, Dec. 21, 1%1, Jan. 29, 1961, and March 8, 1962, diversities at Port Aransas ranging 14-23 species per thousand decreased as one passed north in Aransas Bay to 1, 6, 6, 5, and 8 species per thousand. In contrast, the spring and summer series, April 16, May 25, and June 12, showed little difference between Port Aransas and the northern end; diversities were 10 to 18 species per thousand throughout. During this period salinity ranged from 29 to 33%0 at Port Aransas, as compared to lower values of 24 to 27%0 at the northern end of the series. Total phosphorus values were 76, 75, and 55 ppb, May 28, 1961. Redfish Bay, the shallow bay opposite Port Aransas (Fig. 1) is covered with benthic communities such as turtle grass and has a more constant salinity. Salinities during the 1962 period were between 25 and 33%0 • Species diversities on March 16, 1962, were 11, 13, 11, 10, 9, 19, and 13. On April 13, 1962, values were 14, 15, 8, 10, 10, 4, 10, 14, and 14. On May 23, 1962, the values were 13, 17, 14, 16, 17, 16 ,18, and 11 species per thousand; and 16, 11, 13, 12, 10, and 11, on June 7, 1962. In addi­tion to total phosphorus analyses reported for 1962 (Fig. 3), 41and37 ppb were found July 31, 1961, and 48 and 26 ppb July 5, 1961. Sabine Bay (Lake) in east Texas receives the Sabine and Neches Rivers and has a low salinity community. Although there are heavy waste flows in the system, much of it by-passes the main Sabine Bay via the Beaumont-Port Arthur Ship Channel. In a traverse, the length of the bay, species diversities on April 7, 1962, were 15, 9, 7, 12, and 9 species per thousand; and on July 17, 1962, species diversities were 8, 6, 6, 4, 9, and 16 species per thousand. Total phosphorus of 288 and 128 ppb was measured in the Sabine jetties. Matagorda Bay was studied for species diversity. In the main bay on March 22, 1962, diversities were 10, 9, 10, and 11 species per thousand. On June 22, 1962, values were 9, 17, 19, and 5 species per thousand. Lower values (3, 6, and 4) were found in Lavaca Bay and near Palacios ( 4 and 4) . Wastes were received in these areas. In the south and east portion of Matagorda Bay total phosphorus on August 15, 1961, was 108, 116, 135, 89, 108, 119, and 121 ppb. In Lavaca Bay, May 28, 1961, total phosphorus in ppb was 204, 82, and 286; in Tres Palacios Bay values were 490, 447, and 494 ppb; and in the Colorado River, 216 and 225 ppb. Copano Bay which receives extensive bleedwaters had 175, 178, 240, 248, 118, and 144 ppb phosphorus on June 12, 1961. Freeport Jetties showed total phosphorus on the north side to be 133 and 153 ppb on Oct. 14, 1961. In Baffin Bay, on April 27, 1961, total phosphorus was 98 and 254 ppb at the eastern end. In Alazan Bay values were 98 ppb on Feb. 9, 1961; 4 and 86 ppb March 1961; and 3, 10, 15, 40, 36, and 49 ppb in August 1960. Discussion One result of these studies was the verification of the diurnal curve method of estima­ing carbon and oxygen metabolism in the whole bays by widespread simultaneous sampl­ing, by averaging curves, by averaging levels, and by considering each bay as a single swirling biogeochemical system. The phosphorus, Ohle anomaly, and diversity measures helped to confirm interpretations based on the diurnal oxygen and pH patterns. The several types of measurements tested showed some anomalies or extremes in magnitude in the bays receiving waste discharges, but the differences were in degree and there were no sharp boundaries between data from systems disturbed and undisturbed by wastes. Most of the extremes found associated with waste conditions have occasionally occurred without the influence of wastes. TOTAL PHOSPHORUS The general levels of total phosphorus were somewhat documented in a previous paper as about 40 ppb in the open Gulf increasing to about 150 ppb in the hypersaline bays (Odum and Wilson, 1962). In this paper the levels of phosphorus in the bays receiving wastes ranged generally higher up to 2000 ppb or more. The sources of wastes from treated municipal wastes, seafood processing wastes, bleedwaters, and some in­dustrial wastes were characterized by higher phosphorus values. Thus, values even higher than the natural values in the hypersaline bays were found in Galveston Bay, Conn Brown Harbor, Corpus Christi Harbor, Corpus Christi Bay and ~lsewhere. The higher values in Corpus Christi Bay in 1961 and 1962 when the salinities were high in the bay (35 to 36%0) contrast with some low values in 1957 and 1959 when salinities were lower and less industrial and municipal wastes were incoming. The total phosphorus measurements may be useful as indicators of the retention of relatively high levels of waste, especially when the high levels of phosphorus are accompanied by a decrease in effective metabolism. The accumulations of total phosphorus in the larger Texas Bays can readily serve as major fertilization influence exchanged into the open Gulf abruptly at times of strong cold fronts, low tidal set, or with flood conditions, causing freshwater flushing. METABOLISM FROM DIURNAL CURVES The metabolism and diurnal curve patterns in the bays receiving wastes ranged from very slight metabolism to very large values both in comparisons from place to place and also from time to time in the same place. The very large rates of photosynthesis and respiration in some instances in Galveston Bay ( 40 to 60 g/m2 per day) were equal to or greater than the high natural values in turtle grass of the lower Laguna Madre. Low metabolic rates (1-3 g/m2 per day) suggest toxicity in some stations in ship harbors, near Texas City, and in some instances in the larger bays. However values were not lower than in some graphs associated with extreme natural conditions such as in the Mexican Laguna Madre. METABOLIC QUOTIENTS As already found by Park et al. (1958) in some bays less affected by wastes, the ratio of carbon and oxygen metabolism from diurnal curve methods often deviated from the range of simple metabolic patterns (between 0.7 and 1.0 for glucose, protein, or fats). Thus, the metabolic quotients mainly ranged from 0.4 to 1.9. In bleedwaters strange diurnal ratios (Fig. 9 and Table 4) were traced to the out-of-phase pattern of photosynthesis and respiration in the cycle from daytime oxidative conditions to night­time reducing conditions with some carryover of residual products the following day. EFFICIENCIES OF GROSS PHOTOSYNTHESIS With multiple stations replicating diurnal data from the same bay and with accurate pyrheliometric measurements of available energy, it has been possible to accurately measure the range of photosynthetic efficiency found in Texas Bays, mainly 2.of productivity. Limnol. and Oceanogr. 4: 499-502. Breuer, J. P. 1962. An ecological survey of the lower Laguna Madre of Texas, 1953-1959. Pub!. Inst. Mar. Sci. Univ. Tex. 8: 153-183. Brillouin, L. 1957. Science and information theory. Academic Press, N.Y. 351 p. Bruce, H. E., and D. W. Hood. 1959. Diurnal inorganic phosphate variations in Texas Bays. Puhl. Inst. Mar. Sci. Univ. Tex. 6: 133-145. Chambers, G. V., and A .K. Sparks. 1959. An ecological survey of the Houston Ship Channel and adjacent bays. Pub!. Inst. Mar. Sci. Univ. Tex. 6: 213-250. Connell, C. H., and J.B. Cross. 1950. Mass mortality of fish associated with the protozoan Gonyaulax in the Gulf of Mexico. Science 112: 354--363. Copeland, B. J. 1963. Oxygen relationships in oil refinery effluent holding ponds. Ph.D. Thesis, Oklahoma State University, Stillwater, Okla. 110 p. Copeland, B. J. and Troy Dorris. 1962. Photosynthetic productivity in oil refinery effluent holding ponds. J. Water Poll. Contr. Fed. 34: 1104--1111. Gleason, H. A. 1922. On the relation between species and area. Ecology 3: 158-162. Gunter, G. 1942. Offats Bayou, a locality with recurrent summer mortality of marine organisms. Amer. :\lid!. Nat. 28: 63Hi33. Hohn, :\I. 1959. The use of diatom populations as a measure of water quality in selected areas of Gah-eston and Chocolate Bay, Texas. Pub!. Inst. Mar. Sci. Univ. Tex. 6: 206-212. Hood, D. W. 1953. A hydrographic and chemical survey of Corpus Christi Bay and connecting water bodies. Texas A&M Research Foundation Report No. 40. 23 p. Maney, K. H., and W. C. Westgarth. 1962. A galvanic cell oxygen analyzer. J. Water Poll. Contr. Fed. 34: 1037-1051. Margalef, R. 1957. La teoria de la informacion en Ecologia. Mem. Real Acad. Ciencias Artes. (Barcelona) 32: 373-449. Margalef, R. 1961. Communication of structure in planktonic populations. Limnol. and Oceanogr. 6: 124--128. McFarland, W. N., and J. Prescott. 1959. Standing crop, chlorophyll content and in situ metabolism of a giant kelp community in southern California. Pub!. Inst. Mar. Sci. Univ. Tex. 6: 109-139. Minter, K. W. 1964. Standing crop and community structure of plankton in oil refinery effluent holding ponds. Ph.D. Dissertation, Oklahoma State University, Stillwater, Okla. Odum, H. T. 1953a. Factors controlling marine invasion in Florida fresh waters. Bull. Mar. Sci. Gulf and Caribb. 3: 134--156. Odum, H. T. 1953b. Dissolved phosphorus in Florida water. Fla. Geo!. Surv., Tallahassee, Fla. Report of Investigations 9: 1-40. Odum, H. T. 1960a. Ecological potential and analogue circuits for the ecosystem. Amer. Sci. 48: 1-8. Odum, H. T. 1960b. Analysis of diurnal oxygen curves for the assay of reaeration rates and metabo­lism in polluted marine bays, p. 545-555. In E. Pearson (ed.), Waste disposal in the marine environment, Pergamon Press, N. Y. 569 p. Odum, H. T. 1960c. The requirement for freshwater in a general plan for multiple development of the marine bays. Proc. 6th Annual Conference on Water for Texas, A&M College, p. 32-34. Odum, H. T. 1963. Productivity measurements in Texas Turtle Grass and the effects of dredging an intracoastal channel. Pub!. Inst. Mar. Sci. Univ. of Tex. 9: 48-58. Odum, H. T., J. Cantlon, and L. S. Kornicker. 1960. An organizational heirarchy postulate for the interpretation of species-individual distributions, species entropy, ecosystem evolution, and the meaning of a species variety index. Ecology 41: 395-399. Odum, H. T., and C. M. Hoskin. 1958. Comparative studies on the metabolism of marine waters. Puhl. Inst. Mar. Sci. Univ. Tex. 5: 16-46. Odum, H. T., and R. Wilson. 1962. Further studies on reaeration and metabolism of Texas Bays, 1958-1960. Pub!. Inst. Mar. Sci. Univ. Tex. 8: 23--55. Ohle, W. 1953. Die chemische and electrochemische bestimmung des molekular gelosten sauerstoffes der Binnenge Wasser. Mitt. Int. Rev. Theor u. Ang. Limnol. 3: 1-44. Oppenheimer, C. H., N. B. Travis, and H. W. Woodfin. 1961. Distribution of coliforms, salinity, pH and turbidity of Espiritu Santo, San Antonio, Mesquite, Aransas, and Copano Bays, Texas. Water and Sewage Works: 298-307. Park, K., D. W. Hood, and H. T. Odum. 1958. Diurnal pH variation in Texas Bays and its appli­cation to primary production estimation. Pub!. Inst. Mar. Sci. Univ. Tex. 5: 47-64. Reish, D. J. 1960. The use of marine invertebrates as indicators of water quality, p. 92-103. In E. Pearson (ed.), Waste disposal in the marine environment. Pergamon Press, N. Y. 569 p. Strickland, J. D. H. 1960. Measuring the production of marine phytoplankton. Bull. No. 122. Fish. Res. Board of Canada. 172 p. Wilson, R. F. 1963. Organic carbon levels in some aquatic ecosystems. Pub!. Inst. Mar. Sci. Univ. Tex. 9: 64--76. Directions for the Determination of Changes Ill . Carbon Dioxide Concentration From Changes in pH1 RoBERT J. BEYERS, JAMES L. LARIMER, HowARD T. ODUM, RICHARD B. PARKER, AND NEALE. ARMSTRONG The University of Texas, Institute of Marine Science and Department of Zoology, Port Aransas and Austin Abstract This is a methods paper describing a tonometer apparatus and procedures for the determination of changes in total carbon dioxide concentration in waters from measurements of pH. Where pH changes in water result from the metabolic addition or subtraction of carbon dioxide, continuous records of metabolism may" be obtained from pH recordings. The calculations are facilitated by tables and a computer program. A sample calculation is included. Introduction In most natural waters, the pH of the water is a function of the dissolved carbon dioxide, and as the carbon dioxide content of the water varies so will the pH of the water vary. This relationship between pH and carbon dioxide has been used in many quantitative and qualitative studies of metabolic carbon dioxide changes in both field and laboratory situations. (Osterhout and Hass, 1919; Hass, 1919; Atkins, 1922, 1923; Wells, 1922; Brujewicz, 1930; Verduin, 1951, 1956a, b, 1957, 1960; Jackson and McFadden, 1954; McQuate, 1956; Odum, 1957a, 1957b; Revelle and Emery, 1957; Park et al., 1958; Jackson and Dence, 1958 ; Richman, 1958; Hepher, 1959; Wright, 1960; Larimer, 1961; Megard, 1961; Beyers, 1962, 1963a, b; Delco and Beyers, 1963). However, as pointed out by Beyers and Odum (1959, 1960) and Lyman (1961), some of these efforts have not always been free of error. The source of difficulty lies in the nonlinearity of the relationship between carbon dioxide concentration and pH. Change in pH can be translated into change in carbon dioxide in one of two ways: (1) theo­retically from computations involving alkalinity and dissociation constants; or (2) em­pirically by titration or gas analysis. The theoretical methods assume that natural waters are simple solutions containing carbon dioxide equilibria alone, and that they follow simple chemical laws. However the many different dissociation constants in the literature (Black, 1961) indicate the variable nature of the components and equilibria. Verduin (1956a) empirically determined the relationship between pH and carbon dioxide con­centration by titration with strong acids and bases, but Beyers and Odum (1959, 1960) and Lyman ( 1961) indicated that over some pH ranges strong acids or bases could not be used to simulate carbon dioxide. In these previously published notes, carbon dioxide saturated distilled water was described as a titrant for obtaining pH-carbon dioxide 1 These studies were aided by the National Science Foundation through grants NSF G-13160 and NSF G-23568. Computer programming was accomplished under WP 00204--03. graphs. In effect, the procedure w!ls a titration with gaseous carbon dioxide using dis­tilled water as a carrier. A known amount of gas (in a known amount of distilled water) was added to the experimental water and the change in pH was measured. From these data a graph was constructed correlating change in pH with change in carbon dioxide concentration. The curves were then used to estimate metabolic rates of aquatic organisms and eco­systems from pH changes (Larimer, 1961; Beyers, 1962; Delco and Beyers, 1963; Beyers, 1963a). The method has now been used to compute approximately 300 diurnal carbon dioxide rate of change curves at the Institute of Marine Science and a similar number for Mr. John Butler and Dr. Troy Dorris at Oklahoma State University. The method has also been used to measure the respiration of chironomid larvae at Oklahoma State University and decapod crustacea and small minnows at the University of Texas. This paper provides an account of the apparatus, procedure, and a sample calculation on sea water. Dr. K. G. Wood of Thiel College provided a comparison graph done by the Van Slyke method (Wood, 1963). In the following description, directions are given for ( 1) preparing the carbon dioxide saturated water with a tonometer burette, ( 2) titrating the sample water and (3) com­puting the total carbon dioxide changes. Tables of constants to aid the calculations and a computer program to calculate carbon-dioxide rate of change curves are also included. Procedure ( 1) PREPARATIO~ OF CARBON DIOXIDE SATURATED DISTILLED wATER Pure carbon dioxide at a flow rate of about 555 cc/min is passed through a copper coil (264 cm long, 0.75 cm inside diameter) to bring the gas to room temperature. The gas goes next to two Fieher-Milligan gas washers ( 27 4 cc volume) in series. These gas washers saturate the carbon dioxide with water vapor. The gas next encounters a "Y," one leg of which is closed with a clamp. The other leg leads through a long narrow tube into the barrel of the tonometer burette. This burette is pictured in its cradle in Fig. 1. The specifications for the burette and cradle are given in Table 1. Approximately 60 cc of distilled water is injected into the bulb B with a hypodermic syringe. Care is taken to keep water out of the barrel. The tube carrying the water-saturated carbon dioxide is inserted into the burette through the opening 0 and pushed down into the M FIG. 1. Tonometer burette in its cradle. Tonometer is rotated in this position to prepare carbon dioxide saturated distilled water. Burette is turned upright for titration. Opening 0 admits the gassing tube. B is the bulb which turns on the rollers R. Stopcock S, allows the introduction of carbon dioxide into the tonometer when it is in the upright position. Stopcock S, controls the flow of titrant during the titration. The motor M rotates the tonometer at 30 rpm during the equilibration period. TABLE 1 Specifications for tonometer burette and cradle. Burette is fabricated from a standard 50 ml burette graduated in 0.1 ml increments. Outside diameter of bulb Outside diameter of barrel Outside diameter of delivery tube below stopcock S, Total length of barrel Total length of delivery tube Distance from base of bulb to first graduation on burette Distance from bottom of stopcock S, to first graduation Total length of tonometer Slope of burette barrel in cradle Motor 10.14 cm 1.36 cm 0.79 cm 77.19 cm 13.00 cm 17.49 cm 12.86 cm 104.00 cm 60 '.\lode! SG15-30 RPM Yrerkle-Korff Gear Co. 213 Morgan St., Chicago, III. barrel until the end comes to rest near stopcock S2 which is closed. The stopcock S1 is also closed at this time. The motor M is started and the tonometer rotated at 30 revolu­tions per minute for twenty minutes. The bulb turns on the rollers R. During the rotation the carbon dioxide fills the barrel and bulb of the burette and saturates the water in the bulb. The water is spread out in a thin film on the sides of the bulb, and the film is constantly renewed as the bulb rotates. This action hastens the equilibrium of the C02 with the distilled water. During the rotation a standard mercurial barometer is read and the temperature of the barometer taken. After twenty minutes have elapsed, the motor is turned off. The small gassing tube is withdrawn from the burette and clamped. The stopcock S1 is opened and the carbon dioxide is again admitted into the tonometer via the larger diameter tube attached to the other leg of the Y. The tonometer is inverted and water is allowed to run down into the barrel. This inversion is done gently avoiding any bubble formation. The tonometer is then placed in a burette clamp and about 10 ml of titrant is drawn into a small beaker. This procedure provides a sample of titrant for temperature determination and also provides that saturated carbon dioxide water will fill the delivery tube below stopcock Sz. The burette and titrant are now ready for the titration. (2) TITRATING THE CARBON DIOXIDE WATER vs pH The water to be used is bubbled with carbon dioxide-free air or nitrogen until the pH of the sample is above the range of metabolic interest. A sample of the high pH water 100, 200, or 300 ml in volume is pipetted into a beaker for the· titration. The titrant is introduced from the burette tip in 0.1 or 0.2 ml increments under the surface of the sample water. After each increment of titrant is added the pH of the sample is measured. Stable pH's are achieved in 10 to 15 seconds after the introduction of the carbon dioxide water provided the sample is gently stirred with a stirring rod or magnetic stirrer in such a way as not to break the surface of the liquid. A table of data results like the first two columns in Table 2. As Lyman (1961) has pointed out, in performing titrations to obtain pH-carbon dioxide correlation curves, the volume of distilled water added must not be so large as to change significantly the alkalinity of the sample water. An average titration of a 300 ml sample requires about 15 ml of carbon dioxide-water, a volume which alters the alkalinity by a maximum of only 5% at the end of the titration. Since the quantity of water in the sample beaker changes after each TABLE 2 Data from a typical carbon dioxide-water titration of sea water. This water was taken from the vicinity of Woods Hole, Mass. The table shows the pH of the sample after the addition of each in­crement of titrant (Column 1) ; the mis of titrant added (Column 2) ; relative concentration of carbon dioxide in the sample after each addition of titrant using the relationship in equation (11) (Column 3) ; and the actual concentration of carbon dioxide in the sample after each addition using the relationship in equation (10) and Dr. K. G. Wood's determination of X (Column 4). The quantity X represents the carbon dioxide concentration at the start of the titration. A 300 ml sample was used. Relative Aclual concenlration of co2 concentration of co2 pH of ml of titranl in the sea water in the sea water sea water added (mM/I) (mM/I) 8.93 0.0 x+ o.oao 1.424 8.91 0.2 x + 0.022 1.445 8.89 0.4 X+0.045 1.467 8.87 0.6 x + 0.067 1.488 8.82 0.8 x + 0.089 1.509 8.80 1.0 x + 0.112 1.531 8.78 1.2 x+ 0.133 1.552 8.75 1.4 x + 0.156 1.573 8.72 1.6 x + 0.178 1.594 8.70 1.8 x + 0.200 1.615 8.68 2.0 x + 0.222 1.636 8.66 2.2 x + 0.244 1.657 8.62 2.4 x + 0.266 1.678 8.59 2.6 x + 0.288 1.699 8.57 2.8 x+o.309 1.720 8.54 3.0 x + 0.331 1.741 8.51 3.2 x + 0.353 1.762 8.49 3.4 x + 0.375 1.783 8.45 3.6 x + 0.397 1.804 8.42 3.8 x + 0.419 1.825 8.40 4.0 x + 0.440 1.846 8.36 4.2 x+o.462 1.867 8.33 4.4 x + 0.484 1.887 8.30 4.6 x + 0.506 1.908 8.26 4.8 x + 0.527 1.929 8.22 5.0 x+ o.549 1.949 8.18 5.2 x + 0.570 1.970 8.15 5.4 x + 0.592 1.991 8.11 5.6 x + 0.613 2.011 8.07 5.8 x + 0.635 2.032 8.03 6.0 x + 0.656 2.052 7.99 6.2 x + 0.678 2.073 7.92 6.4 x+o.699 2.094 7.85 6.6 x + 0.721 2.114 7.80 6.8 x + 0.742 2.134 7.74 7.0 x + 0.763 2.155 7.66 7.2 x+ o.784 2.175 7.60 7.4 x + 0.806 2.196 7.51 7.6 x + 0.827 2.216 7.44 7.8 x + 0.848 2.236 7.39 8.0 x + 0.869 2.257 7.32 8.2 x + 0.891 2.277 7.27 8.4 x + 0.912 2.297 7.21 8.6 x+ o.933 2.317 7.16 8.8 x+o.954 2.337 7.10 9.0 x + 0.975 2.358 7.05 9.2 x+ o.996 2.378 7.01 9.4 x + 1.017 2.398 6.97 9.6 x + 1.038 2.418 6.93 9.8 x + 1.059 2.438 6.90 10.0 x + 1.080 2.458 6.87 10.2 x + 1.101 2.478 6.83 10.4 x + 1.121 2.498 6.80 10.6 x + 1.142 2.518 TABLE 2-Continued Relativt) Actual concentration of co2 concentration of co:,! pH of ml of Litrant in the sea water in the sea water sea water added (mM/l) (mM/I) 6.78 6.75 6.72 6.70 6.67 6.63 6.60 6.58 6.50 6.42 6.37 6.31 6.28 6.23 6.20 6.12 10.8 11.0 11.2 11.4 11.8 12.2 12.6 13.0 14.0 15.0 16.0 17.0 18.0 19.0 20.0 22.0 x + l.163 x+ l.184 x+ 1.205 x + 1.225 x + 1.267 x + 1.308 x + 1.348 x + 1.390 x + 1.492 x + 1.594 x + 1.695 x+ 1.795 x + 1.895 x+ 1.994 x + 2.092 x + 2.287 2.538 2.558 2.578 2.597 2.637 2.676 2.716 2.755 2.853 2.950 3.047 3.143 3.238 3.333 3.427 3.614 introduction of titrant, the constantly changing volume must be corrected to a one liter basis by using the "F" factors before plotting the graph. After the titration, the sample may be used for other purposes. The fact that the sample is altered only by the addition of a few ml of distilled water is of great advantage in applications of this method to work where water is at a premium. (3) COMPUTING TOTAL CARBON DIOXIDE CHANGES The carbon dioxide concentration of the titrant after equilibration in the tonometer is a function of the barometric pressure and the temperature according to the laws for the solubility of gases. From the basic data of Bohr (1899) a table of M .values for carbon dioxide concentration in distilled water was calculated on a CDC 1604 computer using the relation: M = (B -btb -Wtt) (a,t) (1) (Bs) (ml/mM) where M is the millimoles C02 per ml of titrant. B is the observed barometric pressure in mm Hg. btb is the brass scale temperature correction in mm Hg at the temperature of the barometer. Wt, is the water vapor pressure in mm Hg at the temperature of the titrant. a is the absorption coefficient at the temperature of the titrant. B. is the standard barometric pressure, 760 mm Hg. ml/mM is the volume of carbon dioxide per millimole, 22.4 ml/mM. The part of the M table in the most useful range of temperatures is reproduced as Table 3. The entire program on cards may be obtained from the program library of the University of Texas Computation Center in Austin. Table 3 is entered with the values for the observed barometric pressure ( B) and the temperature of the titrant and the barometer (tb and tt). Table 3 was calculated on the assumption that these two tempera­ M values for observed barometric pressures between 550 and 799 mm Hg temperatures between 19.0 and 26.8° C. These values were calculated from the relationship expressed in equation ( 1). These tables should be entered with the observed barometric pressure and the temperature of the titrant and the barometer. These values hold good only if a brass scale barometer is used and the temperature of the titrant and the barometer are the same. TEMPERATURE 19.00 550.0000 .0281782 551.oooo • 0262310 552.0000 .0282838 553.0000 .0283366 554. 0000 .0283895 555.0000 .02841t23 556. ooco .0284951 557.oooo • 0285479 558.0000 .0286007 559.0000 • 0286536 560. 0000 • 0287064 561.0000 .0287592 562.0000 .0288120 563. 0000 .0288648 564 .0000 .0289177 565.0000 .0289705 566. 0000 .0290233 567.0000 .0290761 568. 0000 .029128q 569.0000 .0291818 570.0000 .029231t6 571.0000 • 02928 74 5 72. 0000 .0293402 573.0000 .0293930 574.0000 • 0294459 575.0000 .029498 7 576. 0000 .0295515 577.0000 . 0296043 578.0000 .0296571 579 . 0000 .0297100 580.0000 .0297628 581.0000 • 0298156 582.0000 • 0298684 583.0000 .02992 12 584.0000 .0299741 585. 0000 • 0300269 '586.0000 • 0300797 587.0000 . 0301325 588.0000 .0301853 589.0000 .0302382 590.0000 .0302910 591.0000 • 0303438 592.0000 .0303966 593.0000 .0304494 594. 0000 • 0305023 595.0000 .O'l05551 596. 0000 • 0306079 597. 0000 • 0306607 598.0000 .0307135 599.0000 .030766'9 600.0000 .0308192 601.0000 .0308720 602.0000 . 03092'98 603.0000 .0309777 604. 0000 .0310305 605.0000 .0310833 606. 0000 .03l1361 607.0000 .0311889 608. 0000 .0312418 609. 0000 .0312946 610.0000 .0313474 611. 0000 .0314002 617.. 0000 .0314530 613.0000 .031~059 614.0000 .0315587 615.0000 .0316115 616.0000 • 0316643 617.0000 .0317171 618.0000 .0317700 619.0000 .0318228 620.0000 .0318756 621.0000 .0319284 622.0000 .0319812 623. 0000 .0320341 624. 0000 • 0320869 625.0000 • 032 1397 626. 0000 .0321925 62 7. 0000 .0322~53 628. 000 0 .0322982 629.0000 .0123510 630.0000 .0324038 611.0000 .0324566 632. 0000 • 0325094 633.0000 .0325623 634. 0000 .0326151 635.0000 .0326679 636. 0000 . 0327207 6)7.0000 .0)27135 638.. COOO .0328264 639.0000 . 0328792 640.0000 .0329320 641.0000 • 0329848 642.oooo .0330376 6i.3.0000 ; 0330905 64'9.0000 .033lit33 645.0000 .0331961 646. 0000 .0332489 647.0000 .0333017 648.0000 .0313546 649.0000 .0331t074 650.0000 .. 0334602 651.0000 .0335130 652. 0000 • 0335658 653.0000 .0336187 65•.0000 .0336715 655.0000 .0337243 656.0000 . 0337771 657.0000 .0338300 658. 0000 .. 0138828 659.0000 • 0339356 660. 0000 • 03391:Hi4 661 . 0000 • 0340412 662. 0000 .0340941 663.0000 .0341469 664. 0000 .0341997 665.0000 . 0342525 666. 0000 .0343053 667.0000 .0343582 668.0000 .034H 10 669 .0000 .0341t63R 670.0000 .0345166 671 .0000 • 0345694 672.0000 .0346223 673.0000 .03'96751 674.0000 .0347279 675.0000 .0347807 6 76. 0000 • 0348335 6 77. 0000 .0348864 678.0000 .0349392 679.0000 • 0349920 680.0000 .0350448 681.0000 • 0350'176 682.0000 .0351505 683.0000 .0352033 68lt. 0000 .0352561 685.0000 .035308"1 686.0000 .. 0353617 687.. 0000 .035'9146 688.0000 .0354674 689.0000 .0155202 690.0000 .0355730 691.0000 • 0356258 692 . 0000 .0356787 693.0000 .0357315 694.0000 . 035781t3 695. 0000 • 035837 l 696. 0000 • 0358899 697. 0000 • 0359'928 698.0000 .0359956 699.. 0000 .0360484 100.0000 .0361012 701. 0000 • 0361540 102.0000 .0362069 703.0000 .0362597 704. 0000 . 0363 125 705.0000 . 0363653 706. 0000 . 0364181 707. 0000 . 0364710 708.0000 .0365238 709 .oooo • 0365766 710.0000 .036629't 111. 0000 • 0366822 712.0000 .0367351 711.0000 . 0367879 714.0000 • 0368407 715.0000 .0368935 716.0000 • 0369464 717.0000 • 0369992 718.0000 • 03 70520 719.0000 .0371048 120.0000 .0371576 721. 0000 . 0372105 12 2 . 0000 . 03"12633 723.0000 . 0173161 724.0000 .0373689 725.0000 .037't217 726.0000 .0374746 727.0000 . 0375274 128. 0000 • 03 75802 729.0000 . 0376330 730.0000 • 0376H5tt 731.0000 .0377387 732. 0000 .0377915 733.0000 .0378443 734.0000 . 0378971 735.0000 .0379499 736. 0000 • 0380028 737.0000 . 0380556 738.0000 .038108't 739.0000 .tH8l612 740. 0000 • 0382 140 741.0000 • 0382669 742.000U . 031Hl97 743.0000 .0383725 744. 0000 .03842'53 745.0000 • 03H478 l 746.0000 .0385310 747.0000 . 0385838 748.0000 .0386366 749. 0000 . 0 386894 750.0000 . 0387422 751.0000 .0)87951 752.0000 . 0388479 753.0000 .0389007 754. 0000 • 0389535 755. 0000 • 039006 3 756.0000 • 0390592 75 ·1. 0000 . 0391120 758.. 0000 .0391648 759. 0000 . 0 392176 760.0000 . 0392704 76 1.0000 • 0393233 762 . 0000 . 0393761 763.0000 .0394289 764. 0000 .0394817 765.0000 .03q5345 766. 0000 • 03958 74 76 7. 0000 . 0396402 768.0001) .0396930 769.0000 .. 0397458 110. 0000 • 0397986 771.0000 . 0398515 712 .oooo .0399043 773.0000 .. 0399571 774.0000 • 0400099 775. 0000 • 0400621;) 776.0UOU .0401156 111.0000 • 0401684 778.0000 .040221 2' 779.0000 • 0402 740 780.0000 .0403269 781.0000 . 0403797 782. 0000 .0404325 783.000U . 0404853 784.0000 .0405 381 785.0000 .0405910 786.0000 • 0406438 787.0000 • 0406966 788.0000 .0407494 789.0000 .0408022 790.0000 .0406551 71/l . 0000 • 0409079 .,92.0000 .0409607 793. ooou . 04l0l3"i 794. 0000 . 0410663 795.0000 .0411192 796.0000 .0411720 797. 0000 .0412248 798.000IJ .0412'776 799. 0000 .0413304 TEMPERATURE 19. 20 550.0000 . 0200101 551. 0000 . 0280626 552 . 0000 .0281151 553.0000 .028 1677 554.0000 .0282202 555.0000 .0282727 556. occo .028 3252 55 7.0000 . 0283778 ~58.0000 .028430"3 559.0000 • 0284ij28 560.0000 .0285353 561.0000 .02&5819 562 .. 0000 • 0286404 563. 0000 . 0286929 564 . 0000 .0287454 565.0000 . 0287980 561,. 0000 .0288505 567.0000 .0289030 568.0000 . 0289555 569. 0000 . 0290081 570.0000 .0290606 571.0000 . 0 29 1131 57£.0000 . 0291656 573.0000 .02cn182 5 74. 0000 • 0292707 575.0000 . 0293232 576.0000 .0293757 577.0000 .0294263 578.0000 .02~4808 5 79. 0000 .0295333 580.0000 ;029585 8 581.0000 . 0296384 582 .0000 • 0296909 583.0000 . 0297434 584. 0000 .0297960 585.0000 .0298485 586. 0000 • 02990 10 58 7. 0000 .0299535 588.0000 .030006 l 589.0000 .0300586 590.0000 .0301111 S9l.OOOO . 0301636 592. 0000 .0302162 593 . OOCiO .0102607 594. 0000 .0303212 595.0000 .0303737 5'16. 0000 .0304263 597.0000 .0304788 5'l8.0000 .0305313 599. 0000 • 0305838 600. 0000 • 0306364 601.0000 . 0306R89 602 . 0000 . 0307414 603.0000 . 0107939 604 .oooo .0308465 605. 0000 • 0308990 606. 0000 .0309515 (,0 7.0000 .0310040 608 .C OOO . 0310566 609 .oooo • 0311091 bl0.0000 . 0311616 611.0000 • 0312141 6 12. 0000 .0312667 613.. 00JO . 031311-12 614 . 0000 .0313711 blS.oooo . 03142't3 616 .000C .0314766 6 17.0000 .0315293 618. 0000 .031581'1 619.0000 .0316344 620.0000 .0316869 621.00UO . 0317394 622 . 0000 .0317919 623.0COO .03113445 624. 0000 ;0318970 b25.0000 . OH9495 626.0000 . 0320020 627.COOO • 0320546 628.0000 . 0321071 629.0000 • 0321596 630.0000 .0322121 63 1. 0000 . 0 322647 632.0000 .032 3172 633.GOOO .0323697 h34. 0000 .0324222 6)5.0000 .0324748 636. 0000 .0325273 637.0000 .0325798 638.COOO . 0126323 639.0000 .0326849 b40. 0000 • 03713 74 641.0UOO • 032 76'i9 642. 0000 • 0328424 643.0000 .0328950 644. 0000 • 03294 75 645.0000 .0330000 6't6. 0000 . 0330526 64 7. 0000 .0331051 648.0000 .033l576 649.0000 .0332101 650. 0000 • 033262 7 651.0000 . 0333152 652.0000 . 0331677 653.0000 .0334202 654 . 0000 .0334726 655.0000 .0335253 656.0000 .0335778 657.0000 .0336303 658.0000 .0336829 659. 0000 .0"3"37354 b60.0000 .033787'1 661 . 0000 • 0338404 662.0000 .0338930 66).0000 . 0339455 664.0000 .0339980 665. 0000 • 0340505 666.0000 . 0341031 667.0000 .0341556 668.0000 .03't208l 669. 0000 • 0342606 670.0000 . 0343132 671 . 0UOO • 034365 7 672.0000 .0344182 673.. 0000 .034'9708 674.0000 .0345233 675.0000 .0345758 676.0000 • 0346283 677.0000 .0346809 678.0000 .0347334 679.0000 . 0347859 680.0000 .034838 4 681. 0000 . 03489 10 682 .oooo . 0 349435 683.COOO .0349960 684. 0000 • 0350485 685.0000 .0351011 686.0000 .0351536 687.0000 . 0352061 68R.OOOO .0352586 689.0000 . 03531 12 690.0000 .0353637 691.0000 • 0354162 h92.0000 .0354687 693.0000. .0355213 694. 0000 . 0355738 695.0000 .0356263 696. 0000 . 03567d8 697. 0000 .035 7314 698.0000 .0357839 699. 0000 • 0358361t 700.0000 .0358889 701. 0000 .0359415 702. 0000 .0359940 703. 0000 .0360465 704.0000 • 0360991 705.0000 .0361 516 706.00IJO . 0362041 707 . oooo . 0362566 708.0000 . 0163092' 709.0000 • 036361 7 110.0000 .0364142 111. uuoo . 0364667 712.0000 .0365193 71 3. 0000 .0365718 714. 0000 • 0366243 715.0000 . 0366768 716.00fJO .0367294 717.0000 . 0367Ul9 71&.0000 .0368344 719.0000 .0368869 120.0000 .0369395 721.0000 • 0369920 122 . 0000 . 0370445 723 .0000 • 03 70970 724. 0000 .0371496 725.0000 .037207 1 726.UUOO • 0372546 121. 0000 . 0 373071 728. 0000 .03 73597 729. 0000 .0374122 730.0000 .0374647 731.0000 • 03751 72 732. 0000 • u 375698 733 .. 0001) .0376223 734. 0000 .0376748 735.0000 .0377274 736.0000 . 03777q9 737.0000 .0378324 73A.OOOO . 0378849 739.0000 • 03793 75 740.0000 .0379900 741.0000 . G18042 5 742. 0000 .0380-150 743. 000U . 0381476 744. 0000 .0382001 745. 0000 • 0382526 746. 0000 • 0383051 747.0000 . 0383577 748.0000 .0384102 749. 0000 . 0384627 750.0000 .0385152 751.0000 • 0 3856 78 752. 0000 .0386203 753.00UO .0386728 754. 0000 . 0387253 755.0000 .0387779 756.001)0 . 0388304 75 7. 0000 .038.8829 758. 0000 .0389354 759.0000 .0389880 760. 0000 • 0390405 761 .oooo • 03'10930 762.0000 . 0391456 763.0000 .0391981 764. 0000 .0392506 765.00QO .039303l 766.000U • 0393557 767.0000 .0394082 768.0000 .0394607 769.0000 . 0)95132 110.oocJo .o39565R 771. 0000 . 0396183 772. 0000 . 0396 708 773. 0000 . 0397233 774. 0000 • 0397759 775. 0000 • 0398284 776.0UOU • 03911809 777.0000 .0399334 778.0000 . 0399860 119. 0000 . 0400385 780.0000 .Olt009l0 781. 0000 .040l435 782. 0000 . 040 1961 783.0000 . 0402486 78't. 0000 . 0403011 785.0000 .0403536 786 . coco • 040't062 787.0000 .0404587 788.0000 .04051 12 789. 0000 • 040563 7 790.0000 .040616 3 791. 0000 • 0406688 792. 0000 .0407213 793.0000 .0407739 794 .oooo .0408264 795.0000 .0408ld~ 796. OOG O . 0409314 797.0000 .0409640 798.0000 . 0410365 799. 0000 .04 10890 Changes in Carbon Dioxide Concentration From Changes in pH TABLE 3-Continued TEMPERATURE 19.40 550.0000 .0278421 551.0000 .0278943 552 . 0000 .0279465 553.0000 .0279987 554. 0000 . 0280510 555.0000 .0281032 556. 0000 . 0281554 557. 0000 .0282017 558.0000 .0282599 559.0000 . 0281121 560.0000 .0283644 561.0000 • 0284166 562 . 0000 .02B'i688 563.0000 .0285211 564. 0000 . 0285733 565. 0000 .0286255 566. 0000 .02R6778 567. 0000 .0287300 568.00CO . 0287822 fi69.0D00 .U28H31t4 570.0000 • 028886 7 571.0000 . 0289389 572 . 0000 .0289911 573.0000 .0290434 574.0000 • 0290956 575.0000 .0291478 576. 0000 • 0292001 577.0000 .0292523 578 .COOO .0293045 579.0000 . 0293568 seo.oooo .029.C,090 581. 0000 .0294612 582.0000 .0295135 583.0000 • 029565 7 584 .oooo .0296179 585. 0000 .0296701 586.0000 • 0297224 587.0000 .0297746 588.0000 .0198268 589.0000 .OZ?379l 590.0000 .0299313 591 .0000 .0299835 592. 0000 • 0300358 593.0000 .0300A80 594 .oooo .0301402 595.0000 .0301925 596. 0000 • 030244 7 5'17. 0000 .0302969 5'18. 0000 .0303492 599.0000 .0304014 600.0000 .0304536 601. 0000 • 030505~ 60Z. 0000 .0305581 603.0000 . 0306103 604 .oooo .0306625 605.0000 .0307148 606.0000 • 0307670 607.0000 .0308192 608.0000 .030871'5 609.0000 .0309237 610.0000 .0309759 611. 0000 .0310282 612.0000 .0310804 613.0000 .0311326 614.0000 .0311849 615.0000 .0312371 616.0000 .03122113 611.0000 . 0313416 618.0000 .0313918 619.0000 .0314460 620. 0000 .03l't982 621.00UO .0315505 622 .0000 .0316027 623.0000 .0316549 624 .oooo .0317072 625. 0000 .0317594 626.0000 .0318116 627.00IJO . 0318639 628. cooo .0319161 629.000U .0119683 630. 0000 .0320206 631. 0000 .0320728 632.0000 .0321250 633.0000 .032"1773 634. 0000 .0322295 635.0000 640. 0000 .0322817 .03254211 ,., '"'· 0000641. 0000 .0323139 .0325951 637 .00UO 642 . 0000 .0323ti62 .0326473 636.0000 641.0000 -.P324384 .0326996 639.0000 644.0000 • 0324906 .0327518 645.0000 650.0000 .0328040 • 0330652 646.0000 651.0UOO • 0328563 .0331174 64 7.0000 652. 0000 .012qos5 .0331697 646.00UO 65-J.0000 .0329607 .0332219. 64q.oooo 654.0000 .0330130 .0332741 655.0000 • 0333261 656. 0000 .OHl786 657.0000 .0334308 658.0000 .0334830 659.0000 .OH5353 660.0000 .03351:175 661. 0000 .0336397 662.0000 .0336'!120 66J.OOOO .0331442 664.0000 .OHJ964 665.0000 . 033ti487 666.0llOO .OH900q 667.0000 .0339531 668.0000 .034005'4 669.0000 .0340576 670.0000 .0341098 671. 0000 .03'41620 672.0000 .0342143 67J.OOOO .0342665 674.0000 .OJ43187 675. 0000 • 03437 lO 6 76. 0000 .0344232 677.0000 .0344754 6 79. 0000 .Q34527 J 679.0000 .0345799 680.0000 .0346321 681.0000 • 03468'44 682. 0000 .031t 7366 683.0000 .0347888 684 .oooo .031t84ll 685.0000 • 0348933 686.0000 • 0349455 6ti7.0000 .0349977 688.0000 .03505'00 689.0000 .0351022 690.0000 .03'>1544 691.0000 .0352067 692.0000 .0352589 691.0000 .0353111 691t.OOOO .0353634 695.0000 .0354156 696.0000 .0354678 697.0000 .0355201 698.0000 .0355723 699.0000 .0356245 100.0000 • 035616~ 701.0000 .0357290 702.0000 .0357812 703.0000 .• 0358334 704 .oooo .0358857 705.0000 .0359379 706.0000 .0359901 707.0000 • 0360'424 708.0000 .0360946 709.0000 . 0361468 710.0000 .0361991 111.0000 .0362513 112.0000 .0363035 713. ooc.o .0363558 714.0000 .0364080 715.0000 • 0364602 716. 0000 .0365125 111.0000 .0365647 718.0000 . 0366169 719. 0000 ·. 0366692 720.0000 .0367214 121.0000 .0367736 122.0000 • 0368258 723.0000 .0368781 724.. 0000 .0369303 725.0000 .0369825 726.0000 .0370348 727.0000 .0370870 728.0000 .0171392 729.0000 .0371(115 730.0000 • 037243 7 731.0000 .0372959 732.0000 .0373482 733.0000 .0374004 734.0000 .0374526 735.0000 .0375049 736.0000 .0375571 737.0000 .0376093 738.0000 .0376615 739.0000 .0377138 11t0.0000 .0377660 741.0000 .0378182 742. 0000 • 0378705 743.0000 .0379227 744.0000 .03797't9 7't5. 0000 .0380272 71t6. 0000 .0380794 747.0000 .0381316 748.0000 .0381839 71t9.0000 .0382361 750.0000 .0382883 751.0000 • 0383406 752.0000 .0383928 753.00CO • 0381t450 754.0000 .0384972 755.0000 • 0385495 756. 0000 .0386017 757.0000 .0386539 758.0000 .0387062 759.,0000 .038758'4 760.0000 .0388106 761.0000 • 0388629 762.0000 .0389151 763.0000 .0389673 764.000U .0390196 765.0000 . 0390718 766. 0000 .. 0391240 767.0000 .0391763 768.0000 .0392285 76q.oooo .0192807 110.0000 .0393329 111.0000 • 0393852 772. 0000 .0391t371t 773.0000 .0394896 774.0000 .0195419 775. 0000 780.0000 .039S91tl • 0398553 776. 0000 781.0000 • 0396463 • 0399075 111.0000 782. 0000 .0396986 .0399597 778. 0000 783.0000 .0"197508 .0400120 779.0000 784.0000 .1,)398030 . 0400642 785.0000 .0401164 786. 0000 .0401687 787.0000 .0402209 788.0000 .0402731 789.0000 .ll't03253 790.0000 .0403776 791 .. 0000 .0404298 792.00CiO .Olt0'f820 793.0000 .040'5343 79'4.0000 • 0405ti65 795.0000 ... 040638 7 796. 0000 .0406910 797. 0000 . 0407432 798.0000 . 040795-'f 799.0000 .0408477 TEMPERATURE 19.60 550.0000 .0276141 551.0000 .0277260 552.0000 .0277779 553. 0000 .0278299 554. 0000 .0278818 555.0000 • 027933 7 556. 0000 .0279857 '557 . 0000 • 0280316 5'58.00GO .0280896 5'59.0000 .. 0281415 560. 0000 565.0000 .0281934 .0284531 561. 0000 566. 0000 • 0282454 .0285051 562. 0000 567.0000 .0282973 .028557b 563.0000 568.0000 .0283497. .0286089 564.0000 569 .0000 .0284012 .0286609 5 70.0000 .0287126 571.0000 .0287647 572.0000 .0288167 'i73.0000 .0288686 574.0000 . 028nos 575.0000 580. 0000 585.0000 .02A9725 .OZ92322 • 02(14919 5 76. cooo 581.0000 586. 0000 • 0290244 .0292841 .02"15438 577.0000 5e2.oooo 5ti7.0000 .029076'4 .0293360 .0295957 578. 00CO 563. 0000 588.0000 -0291 283 • 02q39eo .02964 77 51q. oooo 584.0000 'i89.0000 .0291802 .0294399 .02~6996 590.0000 .0297515 591 . 0000 • 0298035 '592. 0000 .0298':J54 593. ocoo .0299073 5~4 . 0000 • 0299593 595.0000 .0100112 596. 0000 • 0300632 597.0000 .0301151 598.0CiUO .0301670 'i99. 0000 .0302190 600.0000 .0302709 60 l.0000 .0303228 602. 0000 .. 0303748 603. 0000 .030426 7 604. 0000 .0304787 605. 0000 .0305306 606. 0000 .0305825 607.0000 .0306345 608.0000 .0306864 609.0000 .0307383 610.0000 .0307903 611.0000 • 0108427 61;'. . 0000 . 0308941 613.0000 .0309461 614 . 0000 .ulO~'ltW 615.. 0000 .0310500 616. 0000 .0311019 617.0000 .0311538 618.0000 .0312058 619.000ll .11312577 620.0000 .0313096 621.0000 .0313616 622.0000 -0314135 623.0000 .0314655 624 . cooo .0315174 625. 0000 .0315693 626. 0000 .0316213 627.CCOO .03l6732 628.C COO .0317251 629.0000 .0317771 !>30. 0000 . 0318290 .631 . 0000 .03188(1"1 632.0000 . 0319329 633. 0000 • 0319848 634. OfJOO • 0320366 635.0000 640.0000 645. 0000 650.0000 655.0000 660.0000 665.0000 6 70. 0000 6 75. 0000 680. 0000 685. 0000 690.0000 6Q5. 0000 700.0000 • 032088 7 .0323484 • 0326081 .0328677 .033l274 .0333871 .0336468 .0339065 . 0341662 .0344259 .03'46855 • 03494 52 • 0352049 • 03546'46 636.0000 641.0000 646. 0000 651.0000 656. 0000 661.0000 666. 0000 671.0UOO 676.0000 681.0000 686. 0000 691.0000 696. 0000 701. 0000 .032 1406 • 0324003 • 0326600 .0329197 .0331 794 .0334391 . 03369~7 . 0339584 .0342181 • 0344178 • 034 73 75 • 03499 72 .0352568 .035'5165 631.0000 6 42 . 0000 647.0000 652. 0000 657.0000 662. 0000 667. 0000 6 72 .0000 6 77 .oooo 682 .. 0000 687.0000 692 . 0000 697. 0000 702. 0000 .0321926 .032 4523 .0327119 .0329116 .OH2"H3 .0334910 .OH7507 .0340104 .f)342700 .0345297 .0347894 .0350491 .0353088 .0355685 638.0000 643.0000 64~.cooo 653.0000 f>S~.0000 663.COOO 668.0000 6 n.oooo 678.0000 683.0000 68~.oooo 693. 0001) 69~.oooo 703 .oooo . 0322445 .0325042 .0327639 .0330236 .0332812 .0335429 .0318026 .0340623 .0343220 .034'itH 1 .0348414 .0351010 .0353607 .0356?04 639.COOO (,44 .oooo 64Q. 0000 654.0000 65"-I . 0000 664. 0000 669.0000 674 .. 0000 679.0000 684 .oooo 689 . 0000 694. 0000 699 .oooo 10·4. coon -.0122964 .0325561 .012~158 • 0330 755 .0333352 .033594? .0338546 .0341142 .0343739 .0346336 . 031t8933 .0351530 .0354127 . 0356723 705.. 0000 .035724) 706. 0000 . 0357762 101.0000 .0358282 708.0000 .03 '>880 1 709.0000 • 0359320 110.0000 • 0359840 111.0000 . 0360359 712.0000 . 0]60878 713.0000 . 0361398 714.0000 .036l9l 7 715.0000 120.0000 .0362436 .0365031 716.0000 721.0000 • 03621156 .0365553 7 l 7. 0000 722. 0000 .0363475 .0366072 718.0000 723 .0000 .0J639q5 • 0366591 719.0000 724. 0000 .0364S 14 . 0367111 725.0000 .0367630 726.0000 .0368150 727.0000 .0368669 728.0000 • 0369188 77.9.0000 .0369708 730. 0000 .037022/ 731.0000 .0370746 732. 0000 .0371266 733.0000 . 0171785 734. 0000 .0372304 735.0000 .0372824 736. 0000 .0373343 737.0000 • 0373863 738.0000 . 0374382 7 39 . 0000 .. o :H4901 740. 0000 .0375421 741.0000 .0375940 742 .oooo .0376459 743.0000 .0376979 744. 0000 .0377498 7..5. 0000 .0378018 746.0000 • 0378537 747.0000 • 0379056 748.0000 .0379576 7'49.0000 .0380095 750.0000 .0380614 751. 0000 .0381134 752 . 0000 .0381653 151.0000 . 0382172 754 .oooo .0382692 755.0000 . 0383211 756. 0000 .0183731 757.0000 ... 0384250 758.0000 .0394769 759.0000 .0385289 760. ooou 765.000U 110.0000 .0385808 • 0388'·0 5 .0391002 761 .00llO 766. 0000 771.0000 • 038632 7 • 0388924 . 0391521 762.0000 767.. 0000 112.0000 .0386847 .0389'f44 • 0392040 161.0000 Jhti.0000 113. 0000 .U)tl7366 . 0189963 .0192560 764.0000 16q.oooo 774.0000 .0387886 .0390482 .OJ?J079 775.0000 • 039359(1 776. 0000 . 0394118 777. 0000 .0394637 778.0000 .0195157 779.0000 .03115676 780.0000 .03'16195 781. 0000 • 0396715 782.0000 .0397234 783.0000 .0397754 784 .cooo .0198273 785.oooo • 03q9 792 786.0000 .039~312 787.0000 .0399831 788.0000 .0400350 789.0000 • 04008 70 790. 0000 .040138~ 791.0000 • 04019QQ. 792. 0000 .040l428 793.. 0000 .0402947 794 .oooo .0403467 79'5. 0000 .IJ403'-'86 796.00(10 • 04114505· 1(11.0000 .0405025 790.0000 . 0 405544 7~9. 0000 .0406063 Changes ~n Carbon Dioxide Concentration From Changes in pH TABLE 3--Continued TEMPERATURE 19.80 5 50.0000 .0275372 551 . 0000 • 0275889 552.0000 • 02 76•06 553.0000 . 02 76923 55lt.OOOO .0211..0 555 .0000 • 027795 7 556. 0000 . 02784 7.\ 557.0000 • 0278991 558.0000 .02 79508 559 . 0000 • 0280025 560. 0000 .0280542 561 . 000 0 .0281059 56 2.0000 . 028 1576 563.00 00 .02 82093 564 .oooo .0282b l0 565. 00 00 .0283128 566. 0000 • 02836lt 5 56 7. 0000 . 0284162 568.0000 . 0284679 569. 000 0 .0285196 5 70 . 0000 . 0285713 5 7l.0000 • 0286230 572.0000 .02867lt7 57 3 . 0000 . 02872 64 574 . 0000 . 028778 1 575.0000 . 0288298 5 76. 0000 .0288 815 57 7 .0000 .0289332 578.0000 .028984 9 579. 0 000 • 0290 3 66 seo.oooo . 0290883 58 1. 0000 .029 14t00 582 . 0000 . 02919 17 583. 0000 . 0292.ft)lt 584.0000 .0292951 585. 0000 . 02'H468 586 . 0000 . 0293985 587. 0000 . 029't502 588.0000 .02950 19 5 89 . 0 000 .0295 536 590.0000 . 0296053 591. 0000 . 0 296570 592 . 0000 .0297087 593 . 0 000 .0297601t 5 91t . 000 0 • 0298121 595 . 0000 . 0298638 596.0000 .02991 55 597 . oooo .02q9672 598. 0000 .0300189 599 . 0000 .0300 706 600 .. 0000 .0301223 601 . 0000 .0301 7 40 602 . 0000 . 03"02257 603.0000 .030277't 6 0 lt. OOO O . 0303291 605 .00 00 . 0 303808 606.0000 .030it3 25 6 0 7 . oooo • 030481t2 608.. 0 000 .0 30 5 3 5 9 609.00 0 0 .0305 8 7 6 6 10. 0000 . 030 6 393 611.0000 .0306910 612.0000 . 0307427 613. 0000 .03 0 79't4 6 l lt. 0000 .0308'61 6 15. 0000 .03089 78 61 6 .0000 • 0309495 6 17. 0000 .01100 12 6 1 8.0000 .0310529 61 9. 0000 . 03 l l01t6 620.0000 . 0311563 621.0000 .031 208 0 622.0000 .0312597 623.0000 .03lltllt 621t . 0000 .0313631 62 5. 0 0 00 .03litl48 626. 0000 . Olllt665 627.0000 .031 5 182 628 .0000 . 0 31 5699 629. 0000 . 0316 2 16 630.0000 . 03167 33 63 1.0000 .0317250 632 . 0000 . 0317767 633. 0000 . 0 318281t 6 31t . 0000 • 031880 1 635.0000 .onqJis 636. 0000 • 0319835 63 7. 0 000 . 0320352 638.0000 .0 3 20869 639. 0 000 . 0321386 61t0. 0000 . 032 1903 61t l . 0000 • 01224 20 642 . 000 0 .0322917 61t3 . 0 000 .0323't51t 61t4.0000 . 032 197l 6 45.0000 .0324 488 6't6.0000 • 032500 5 6 4 7.0000 .03255 2 2 61t8 .0000 . 0126039 61t9. 0 000 . 0 326 556 650.000 0 . 0327073 65 1 .0000 . 032 1590 652. 0 000 . 0328107 6 53 .00 0 0 • Ol28621t 654 .0000 . 0 329l'tl 655 .00 0 0 • 0329658 6~6.0000 • 0330115 657 . 0000 .03)0 6 9 2 658. 0 0 00 . 0331209 659 .0000 • 0 331 726 660.0000 . 031224) 661.0000 • U332 760 6 6 2.0000 . 0313277 663.0000 .03H191t 664. 0 000 .0331tHl 665.0000 .U33"828 t.66. 0000 • 0135145 6 6 7.0000 . 0335863 668.0000 .0336380 669.0000 .033689 7 6 7 0 . 0000 . 03374 14 67l . OOOO .0337911 6 72 . 0000 • 03181t 48 673.0000 .0338965 674 . 0000 .0339482 6 75 . 0000 .0339999 676.0000 . 03.\05 16 &77.0000 .031t l 033 6 78. 0 000 .031tl 550 679 . 0000 • 0 3 4206 7 6 80. 0000 .0342'i84 68 1 .0000 • U31t3 10l 682.0000 .031t3618 6 8 3.0000 . 0341t l 3S 684. 0000 . 0 3.\.\&52 685 . 0 0 00 . 0345169 686 . 0000 • 031t5686 68 7 . 0 000 .031\620 3 6 88 . COOO .0346720 689.0000 . 031t7237 6 90. 0000 .0347754 691.0000 • 031t8271 692 . oooo .031t 8788 693. 0000 . 0349305 694. 0000 . 03498 22 695.0000 . 03~033q 696 . 0000 .0350 8 56 6 97 . 0000 • 035 1 3 7 3 698.0000 . 0351890 699.0000 . 03524 01 10 0.0000 . 03'52q24 701 . 0000 .03534'tl 102.0000 .0353958 703.0000 .03544 75 704 . 0000 .035't992 7 0 5 . 0000 .0355509 706.0000 . 0356026 707. 0000 .0356 5't3 708. 0000 .0357060 709.000 0 . 035 7577 110.0000 • 0358094 111.0000 • 0358611 1 12 . 0000 .0359128 713. 0000 .0359645 7 l't.OOOO . 0360162 71 5. 0000 • 0 360679 716. 0000 • 0361196 71 7. 0000 .0361713 718 .0000 . 0362230 719. 0000 .0362 71t7 1 20. 0000 • 0 363264 121. 0000 .0363781 122 .0000 .0364298 723 . 0000 . 0361t81 5 724. 0 0 0 0 .0365332 7 2 5.0000 .0365 8 't9 7 26. 0000 .0366366 72 7 .oooo .0366883 728. 0000 . 0367't00 729 . 0000 .0367917 n o. oooo .036 81t3't 7 31.0000 • 0368 951 732. 0000 . 0369468 733.. 0000 .0169985 731t . OOO O • 0370502 735.00 0 0 .0371019 7 36.0000 .0371536 73 7 .0000 .0372053 738.0000 .03 72570 7 39.000 0 .0373087 74 0.0000 • 0 3 7 3 6 01t 741 . 0000 .037 41 21 7 4 2.0000 . \l371t638 7't3 . 0000 .0375155 71t4. 0 000 .03 75672 71t5.0000 1so.oooo . 0 3 76 18'1 .03 787 74 7't6. 0 000 751.0000 • 0 376 706 . 0 379 2 91 747 . 0000 752.0000 .. 0377223 .03791:108 7"8.0000 753.0000 . 0317740 . 0380325 749 . 0000 7 51t.OOOO . 0378257 • 038081t2 755 . 0000 . 0381359 756. 0000 .. 0381876 75 7 .0000 .0382393 758 . 0 0 00 . 038291 0 7 59 .0000 • 03831t27 760 .0000 • 038 394't 7 6 1 . 0000 .0381tit61 76 2 . 0000 .. 0384 9 78 76 3 .0000 .03851t95 76't . 0000 .0386 0 12 765.00 00 . 0386 529 766. 0 000 . 038701t6 76 7 .0000 .0387 563 768.0000 . 0 3 8808 0 769.0000 .0388597 7 70.0000 . 0389115 7 71. 0000 • 0389632 772.0000 .0390149 773.0000 .0390666 771t . OOOO . 0391 183 7 75. 0000 .0391700 7 76.0000 . 039221 7 777. 0000 .0392734 778. 0000 . 0393251 779 . 0000 .0393 768 7 80. 0000 . 0391t285 781.0000 . 0394802 782 . 0000 .0395319 783.0000 . 0395836 784.0000 .0396353 785.00 0 0 . 0 3 9 6 870 7 86. 0000 .0397387 78 7 . oooo .0397904 788 . 0000 . 0398421 789.0000 • 0398938 7 90.0000 • 039945 5 7 9 1. 0000 .03999 72 792.0000 • 0400489 793 . 0000 . 0401006 791t.OOOO .04 0 1523 795 . 0000 • Oit02040 796 . 0000 .0402557 7 9 7 .0000 .O't03014 798.0000 .04 03591 799.0000 .0401tl08 TEM PE RATURE 20. 00 55 0 . 0000 • 027 3 692 551.. 0000 .02 74 207 552 . 0000 .027't72 1 553.00 00 .027523 5 554 . 0000 . 0275749 55 5.0000 .0276263 556. 0000 .0276777 557.0000 . 027 729 1 558 . 0000 .0277805 559 . 0000 . 0278319 560. 000 0 . 0278833 561 . 0000 .0279347 562 . 0000 .027986 1 563.0000 .0280375 564.0000 . 0280889 565.0000 .028 l 't03 566 . 0000 .028191 7 56 7 . 0000 .0282432 568.0000 . 0282946 569 . 0000 .0283460 570 . 0000 . 028 397't 5 71 .0000 • 0281t488 5 7 2.0000 . 028500 2 573 . 0000 .0285516 574 . 0000 • 0286030 575. 0000 .02865't4 576. 0000 • 0287058 577 . 0000 . 0287572 578.0000 . 0288086 579 . 0000 • 0288600 580 .00 0 0 .0289114 581.00CJO . 0289628 582 . 0000 .0290143 583.0000 . 0290657 58".0000 . 029 11 71 585. 0000 .0291685 586. 0000 .0292191-1 587 . 0000 . 0292713 588.0000 .0293227 589 .oooo . 0293741 590. 0 000 . 0294255 591.0000 .0294769 592 . 0000 .0295283 593.0000 . 0295797 591t.OOOO .0296311 595 . 0000 . 029 6825 596. 0000 . 0297.H9 597 .oooo .0297854 598.COOO .0798368 599.0000 .0298882 600.0000 • 0299396 601.0000 .02991HO 602 . 0000 .0300't24 603. 0000 . 0300938 604 . 0000 . 0301"52 605.0000 . V30l966 606 . 0000 • 03021t80 607.0000 • 0302994 608.0000 .0303508 609 . 0 000 .0301t022 610.0000 .0301t5 36 611 . 0000 • 0305050 6 12.0000 . 0305561t 613 . 0000 .0306079 61" . 0 000 .0306 593 6 15.0000 .0307107 6 16.0000 . 030 7621 6 1 7.0000 . 0308 1 35 618.0000 . 0308649 6 19 . 0000 .0309 163 620.00 00 .0309677 621. 0000 .0310 19 1 622.0000 .0310705 623.0000 . 0 311 2 1 9 621t. 0000 .0311733 625. 0000 .0312247 626.. 0000 .0312761 627.0000 . 031 )275 628 . COOO .03 13790 629.0000 . 031"304 6 30.0000 .031"8 18 631.0000 • 03153 32 632 . 0000 .OH581t6 633. 0000 .0316160 63't. 0000 .011687" 6 35.0000 .0317388 636.0000 .O)l 7902 637.0000 .03 181tl6 63Ei . OOOO .03 18930 639. 0000 .03194't't 61tO.­oooo .0319958 61tl. 0000 .0320472 642 . 0000 . 0320986 64 3 . 0 000 . 032150 1 644 . 0000 .03220 15 645. 0000 .0322529 646. 0000 .0323043 647 . 0000 . 0323557 6't1s.000U . 032407 1 61t9 . 0 000 . 0324585 650. 0000 • 0325099 651 . 0000 . 0325613 652. 0000 . 0326127 653.0000 . 0326641 651t. 0000 .0327155 655.0000 .0327669 656.0000 . 0 328183 657.0000 .0328697 658.0000 . 03292 12 659 . 0000 .0329726 660. 0000 • 03302't0 66 1. 0000 • 0330754 662.0000 .0331268 663 . 0000 . 033178 2 664.0000 .0332296 665.0000 . 0332810 666.0000 . 033332 4 667 . 0000 . 0333838 6t.8.COOO . 033'\152 669. 0000 • 0 3llt866 6 70. 0000 .0335380 671.UUtlO • OB5H'l4 612.0000 . 0336408 673 . 0000 . 0316922 6 7" . 0000 .0337437 6 7 5.0000 . 033795 1 676.0000 • 033 8465 677.0000 . 0138979 67f! . OOOO . 0319493 679 . 0000 .031t0007 680. 0000 .03405 21 681.0000 .0341035 682. 0000 . 03.\ 1 549 68-~.oooo .031t2063 684 . 0000 . 0342577 685 . 0000 .0343091 686.0ULJO • 0 }4 ~605 687.0000 • 03"4119 688. 0000 . 0341t633 689. 0000 . 03"5148 690.0000 . 0345662 691 . 00UO . 03 461 76 692.0000 • 031t6690 691.0000 .034720.lt 6q4 . 001)0 . 0347718 695.0000 .0348232 696. 0000 .o i 48146 697. 0000 .03't9260 69H . 0000 . 03't9774 699. 0000 . 0350288 700 . 0000 • 0350802 701.0000 .03Sl3i6 702 . 0000 .0351830 103.0000 . 03523"4 704 . oooo .03521:159 705.0000 • 03533 7 3 706. oouo .U1538H1 707.0000 .0354401 708 . 0000 .0354915 709.0000 .0355429 710. 0000 . 0355943 111.0000 .0356457 7 12.0000 . 0356971 713 . 0000 .03,57"85 714 . 0000 .0357999 715. 0000 • 0358513 716.0000 .0359027 717.0000 . 035954 1 718.0000 . 0360055 719.0000 . 0160569 120. 0000 .0361084 721.0000 . 0361598 722.0000 .03621 12 723 . 0000 .0162626 72.ft . 0000 .0363l't0 725 . 0000 • 036365't 726.0000 .0364168 727.0000 .0364682 728.0000 .0165196 729.0000 .0365710 730. 0000 . 0366224 73 1. 0000 • 0366138 732. 0000 .0367252 733 . 0000 . 03b7766 734 . 0000 . 0368280 735.0000 .0368195 7 36. 0000 .0369309 737 . 0000 • 0369821 738.0000 . 0370337 719.0000 .0310tl51 7"0. 0000 • 03 71365 1'tl .OOOO .0371879 742. 0000 .0372393 743.0000 . 0172907 744 . 0000 . 0373421 7 45 . oooo .03 7]935 746. 0000 . 03 74449 74 1.0000 .OJ74q63 748.00UO . 03 75477 74'1 . 0000 . 0375991 750. 0 0 0 0 . 0376506 7 51 . 0000 .0377020 752 . 0000 .0377 534 753 . 0000 . 0378048 754 . 0000 .0373562 755.0000 .0379076 756. 0000 • 0379 590 75 7 .0000 . 0380 10't 758 . CCOO . 038061 8 759 . 0000 .0381132 760.0000 . 0381646 761.0000 .0382160 762 . 0000 . 0382674 763 . 0000 . 0383188 76" . 0000 • 0183 702 76 5 .000,0 . 0381t211 766. 0000 . 03847 1 1 76 7. 0000 . 0385245 768.0000 .018575'1 769.0000 • 03862 73 770 . 000b . 03861tl7 771.0000 • 0387301 772 . 0000 .03878 1 5 773.0000 .0388329 774.0000 • 018881t 3 775. 0000 . 038935 , 7 76.0000 .038987 1 171 . 0000 • 039038 5 778.0000 .0390R99 7 79.0000 . 0391413 7 80.0000 .0391927 78 1. 0000 . 0392442 782.0000 .0392956 783.0000 .0393470 784 . 0000 .03939 84 7 85. 0000 • 039'tlt98 786 . 0000 . 0395012 787 .oooo .0395526 788 . 0000 .0396040 789 . 0000 .039655't 790. 0000 • 0397068 791. 0000 .0397582 792. 0000 .0398096 793.0000 .03986 10 794. 0000 .0399124 795. 0000 • 0 3996 38 796.00uO .04001 53 79 7.0000 • O't0066 7 798. 0000 • 040118 I 7.99.0000 .0401695 Changes in Carbon Dioxide Concentration From Changes in pH TABLE 3-Continued TEMPERATURE 20.20 550.0000 .0272013 551 . 0000 .0272524 552. 0000 .0273035 553. 0000 .0273546 554 .oooo .u274057 555.0000 560. 0000 • 0274568 .o27UZ4 556. 0000 561.000\J .02 75080 .0277635 557. 0000 562. cooo . 021ssqL . 0278146 55& .0000 563.0000 .07. 76102 .0278657 55q. 0000 564 .oooo .02766 l 3 .0279169 565. 0000 .0279680 566. 0000 .Q280t12 37 706 .0000 .0351748 707.0000 .0352259 708.COOO .0357770 709. 0000 .0353281 71o.0000 .0353792 711.0000 .0354303 71 2. 0000 .03548 15 713. 0000 .0355326 714.0000 .0355837 715.0000 .0356348 716.0000 .0356859 717.0000 .0357370 718.0000 . 03S7881 719.0000 .0358392 120.0000 .0358903 121.0000 .0359415 122.0000 .0359926 723.0000 • 036043 7 724.0000 • 0360948 725.0000 .0361459 726. 0000 .036 1970 727. 0000 .0362.C.81 728.0000 .0362992 729. 0000 . 0363504 730.0000 • 036.C.O l 5 731 . 0000 • 0364526 732. 0000 .0365037 733.0000 .0165548 734.0000 . 0366059 735.0000 .0366570 736. 0001) • 0367081 737 . 0000 .0367593 138.oooo .0368104 739.0000 • 0368615 740. 0000 .0369126 741. 0000 . 0369637 742 . 0000 .0370148 743.0000 . 03 70659 744.0000 .0371170 745.. 0000 • 0371682 746. 0000 .0372193 74 7 . 0000 .0372704 748.0000 .0373215 749 .0000 .0373726 750. 0000 .0374237 751.0000 • 03 74 748 752 . 0000 .0375259 753 . 0000 . 0375770 754 . 0000 .0376282 755 . 0000 .037f.793 756. 0000 .0377304 757 . 0000 . 0377815 758. cooo . 037f\326 759 . 0000 .0378837 760.0000 • 0379348 761.000') .0379859 762 .0000 .0380371 763.0000 . 0380882 764 . 0000 .0381393 765.0000 . 0361904 766.0000 • 0382415 767. 0000 . 0382'126 768.0000 .0383437 769.0000 • 0383948 770.000C .0384460 111.0000 • 0384971 772.0000 . 0385482 773.0000 .0385993 774.0000 .0386504 775. 0000 .0Jfl701 5 776. 000C • 0387526 111.0000 .0388037 778 . 0000 .0388549 779.COOO .0389060 780.0000 . 0389571 781.0000 • 0)90082 782. 0000 .0390593 783-0000 . 0391104 784.0000 .0391615 785.0000 .0392 126 786. 0000 .0392637 787.0000 .0393149 788.COOO .03Q]660 789.0000 .0394171 790.0000 • 0394682 791. 0000 .0395193 792 .oooo .0395704 793.0000 . 03'16215 794.0000 .0396726 795.0000 .039723H 796. 0000 .0397749 797 .. 0000 .0398260 798.0000 .0398771 799. 0000 . 0399282 TEMPERA TURE 20. 40 550. 0000 .0270333 551.0000 .0270841 552. 0000 . 0271349 553 . 0000 .0211858 554 .oooo . 0272366 555.0000 .0272874 556. 0000 . 0213382 557.0000 .0273890 558.0000 .0274399 559 . 0000 .0274907 560. 0000 .0275415 561. 0000 .027'>923 562.0000 .0276.C.31 563.0000 . 0276939 564 . cooo . 0277448 565. 0000 .0277956 566.0000 • 02 78464 567.0000 -02789'72 568. 0000 .0279480 569.0000 . 0279989 570.0000 .0280491 5 71. 0000 • 028100S 511.0000 .0281513 573.0000 . 028202 1 574.0000 • 0282529 575. 0000 .0283038 576. 0000 . 0283546 577.0000 .0284054 57R . OOCO -0284 562 5 79. 0000 • 0285070 580. 0000 • 02855 7lt 581 . 0000 • 02860d 7 582. 0000 .0286595 583.0000 .0287103 584 . 0000 .028761 l 585. 0000 .0288119 S86. 0000 .0288628 587. 0000 .0289136 588. 0000 . 0289644 589.COOO .0290152 590.0000 • 0290660 '591.0000 . 029 1168 592.0000 .0291677 593.0000 .0292 185 594. 0000 .0292693 595. 0000 .0293201 596. 0000 .0293709 597. 0000 .029.C.217 598. 0000 .0294726 599 . 0000 .0295234 600.0000 .0295742 601. 0000 .0296250 602. 0000 .0296 758 603. 0000 . 0297267 604 .0000 . 0297775 605.0000 .0298281 606. 0000 . 0296791 607.0000 . 0299299 608.0000 .0299807 609. 0000 .0300316 610.0000 • 0300824 611.0000 . 0301332 612 . 0000 .0301840 613. 0000 .0302348 614 . 0000 . 0302856 615.0000 .0303365 6 16.0000 • 0303813 617 . oooo .030438 1 618.0000 .0304889 619 . 0000 .030539 7 620.0000 • 0305906 621.0000 .0306414 622.0000 • 0306922 623.0000 .0107430 62.C. . 0000 . 0307938 625.0000 • 0308446 626.0000 .0308955 627.0000 . 0309463 628.0000 .0309971 629. 0000 . 0310479 630. 0000 .0310987 631.0000 . 0311496 632. 0000 . 0312004 6)3.0000 . 0312512 634 . 0000 . 0313020 635.0000 .0313528 636. 0000 .0314036 63 7. 0000 . 0314545 638.0000 .0315053 639.0000 .0315561 640.0000 .0316069 641.0000 .0316571 642. 00!)0 .0317085 643.0000 .0317594 644.0000 .03181 02 645. 0000 . 0318610 646.0000 .0119118 647.0000 . 0319626 648. 0000 .0')20135 649.0000 .. 0320643 650.0000 .0321151 651 . 0000 . (Jl2'1 659 652. 0000 . 0322167 653.0000 .0322675 654 .oooo .0321184 655. 0000 . 0323692 656. 0000 . 0}24200 657.0000 .032.C.708 65~.oooo .0325216 659.0000 .032572.C. 660.0000 . 0)26233 661. OOOCJ . 0 326741 662 . 0000 . 0327249 663.COOO .03 2775 7 664. 0000 . 0326265 665.0000 .0328774 666.0CJOU .0329282 66 7. 0000 .0329790 668.0000 .0330298 669.0000 .0330806 670.0000 .0331314 671 .0000 . 0331823 6 72. 0000 .0332331 671.0000 . 0332839 6 14.0000 . 0333347 675.0000 . 0313855 6 76. 0000 .033"363 677 . 0000 .0334872 67d.OOOO .0335380 679.0000 . 0335888 680. 0000 .0316396 681 . \J UOO • 0336904 6~2 -0000 . 0337413 681. 00'10 . 0337921 684 .0000 .0).38429 685.0000 . 0338937 686. 0000 • 0339445 6117. 0000 .0339953 b8FJ.COOO .0340462 609.0000 .03'r0970 690. 0000 .0341478 691 . 0000 .0341986 692 . 0000 .0342494 693. 0000 .0343002 694. 0000 • 0343511 695. 0000 .034401 9 696. 0000 .0344527 697. 0000 . 0345035 69a . cooo .0345543 6"9.0000 .0346052 700. 0000 .0346560 101 . 0000 .0347068 1oz'.oooo .0347576 703.0000 .0348084 704.0000 .0348592 705. 0000 . 0349101 706. 0UOO • 0349609 707.0000 . 0350117 700.0000 .0350625 709.COOO . 0351133 710.0000 . 035 164 2 711.0000 . 0352150 112.0000 .0352658 113.0000 .0353166 714. 0000 .03536 74 115.0000 .0354182 716.UOOO .u354691 71 7. 0000 .0355 199 718.0000 . 035"i107 719.0000 .0356215 120. 0000 .0356723 121.0000 .0357231 1 22 . 0000 .0357740 723.0000 . 0358248 724. 0000 .0358756 725 . 0000 • 0359264 726.0000 • 035-9772 727.0000 .0360281 728. 0000 . 0360789 729.0000 .0361297 730. ooou .0361805 731.0000 . 0362313 732. 0000 .0362821 733.0000 . ()'363330 734.0000 .0363838 735.0000 .0364346 736.0000 • 0364854 137.0000 .0365362 738 . 0000 .0365870 739 . 0000 .0366379 740.0000 .. 0366887 741.0000 .0367395 7"2 .oooo . 0367903 743.0000 . 0368411 744.0000 • 0368920 745.0000 .0369428 746. 0000 . 0369936 747 . 0000 .0370444 748.0000 .0370952 749.0000 . 0171'460 750.0000 .0371969 751.0000 .0372477 752. 0000 .0372985 753.0000 .0373493 754. 0000 . 0374001 755.0000 .o37't509 756.0000 .0375018 757.0000 .0375526 758.0000 .03 7h034 759.0000 • 0376541 760. 0000 .0377050 761.0000 .0377559 762 . 0000 .037806 7 763. 0000 .037H57'5 764 . 0000 .0379083 765. 0000 .0379591 766.0000 • 0380099 767.0000 . 0380608 768.0000 .0381116 769.0000 . 0381624 770.0000 .0382132 77 1. 0000 . 0382640 772 . 0000 .0383149 773. 0000 .0383657 774.0000 .0384165 775.0000 .0384673 776. 0000 .0385181 777 . 0000 . 0385689 HA.0000 . 0386198 779 . 0000 .0386706 780. 0000 .038721-4 781 . 0000 .O}ljl722 782.0000 .0388230 783.0000 .0388738 784.0000 .0189247 785.0000 .0389755 786.0000 • 0390263 787.0000 .0390771 788.0000 . 0391279 789. 0000 .0391 788 790.0000 • 0392296 791.0000 • 0392804 792.0000 .0393312 793.0000 .0393820 794.0000 . 0394328 795.0000 .0394837 796. 0000 .0395345 797. 0000 .0395853 798. 0000 .0396361 799. cooo .0396069 Changes in Carbon Dioxide Concentration From Changes in pH TABLE ~Continued · eHPEA.ATURE 20.60 550. 0000 .0268965 551.0000 • 02694 71 552. 0000 .0269977 553 . 0000 .0270483 554. 0000 .UZ70981:1 555.0000 . 02714'14 556. 000\J • 0272000 557. 0000 .0272506 ';58.COOO .0273012 1)59.0000 .0273517 560.0000 565. 0000 . 0274023 .0276552 561.0000 566.0000 • 0274529 .0277058 562 . 0000 567. 0000 .0275035 .0277564 563.0000 568.CiOOO .0275541 .0278070 564. 0000 569. 0000 .027604 7 .0?78576 570.0000 .027906 1 571.0000 . 0279587 572.000IJ . 0280093 573. 0000 . 0280599 s74 . 0000 ~CIZB ll Qo; 575. 0000 • 028161 l 576. 0000 . 0282ll6 577.0000 . 0282622 578. COOO .028ll2f\ 5 79. 0000 .0283634 580. 0000 .. 0284140 581. 0000 .0264646 582.0000 .0285151 583.0000 . 0285657 584. 0000 .0286163 585.0000 • 0286669 586.000U .0287175 587.0000 . 0287680 588 . 0000 .0288l86 589.0000 . 0288692 S90.0000 .0289l98 59L.oooo • 0269704 592. 0000 . 02902 l 0 593.0000 .0290715 594 . 0000 . 029l22l 595.0000 .0291727 596. 0000 .0292233 597. 0000 . 029Z739 598. COOO • 0293244 599 .0000 .0293750 600.0000 . 0294256 601.0000 • 0294 762 602.0000 .0295268 603.COOO .0295774 60lt .oooo .0296279 605.0000 .0296785 606. 0000 .029729l 607. 0000 .0297797 608. 0000 . 0298303 609. 0000 .0298808 610.0000 615.0000 .0299314 .0301843 6 11. 0000 616.0000 • 0299820 • 03023't9 612 .0000 6l 7.0000 .0300326 . 0302855 613.0000 618.0000 .0300832 . 0303361 614 . 0000 619.0000 . 03013)8 . 0303867 620.0000 .0304372 621 . 0000 • 0304878 622 . 0000 .0305384 623.0000 .0305890 62lt . CiOOO .0306396 6 25.0000 . 0306902 626. 0000 • 0307lt07 62 7. 0000 .0307913 628.0000 .0308419 629. 0000 • 0308925 630.0000 . 0309431 631. 0000 . 0309936 632.0000 • 03 10442 633.0000 .03109lt8 634.0000 . Oll l'r54 635.0000 6'r0.0000 .03ll~60 .031448'1 636.0000 641. 0000 .0112466 . OH4-i95 637.0000 642.0000 . 03l2971 .03l 5SOO 638.0000 643.0000 .Ol1347 7 .0316006 639.0000 644. 0000 . 0113983 .0316512 645.0000 650.0000 .0317018 • 031954 7 646 . 0000 651. 0000 .Oll 752lt . 0320053 647. 0000 ti52. 0000 .0318030 .0320559 648.0000 653.0000 . 0318535 .0321064 649. 0000 654 .oooo .0]19041 . 0321570 655.0000 .0322076 656.UOOO .0322582 65 7. 0000 . 0323088 658.0000 .0323594 659.0000 .032lt099 660.0000 • 0324605 661. 0000 .032511 l 662. 0000 . 0325617 663.0000 .0326123 664.0000 .0326628 665.0000 . 0327134 666.. 0000 .0327640 667.0000 .0128146 6611.COOO .03?.8652 669.0000 • 0329158 670.0000 .032966] 611.0000 • 0330169 672.0000 .03306 75 671.0000 .033ll81 674.0000 .0331687 675.0000 . 0332192 6 76. 0000 • 0332698 677.0000 .0331204 678.0000 .0333710 679.0000 .033'r216 680.0000 685. 0000 . 0334122 .033'251 681.0000 686.. 0000 .0335227 .0337756 682.oooo 68 7.. 0000 .0335733 .. 03ltt262 68).0000 688.0000 . 0336239 .033876 8 684.0000 689. 0000 .0336745 • 03392 74 6'10.0000 695.0000 .0339781) . 0342309 691.0UOO 6'16.0000 .0340286 • 0342815 6~2.0000 697.0000 .03~0791 . Q343321 693.0000 698.0000 .0341297 .0343826 6CJ4.000 0_ 699.0000 .03H803 .0344332 100.0000 . 0344838 101.0000 • 0345344 702.0000 .03458SO 703.0000 . 0346355 704.0000 • 034686 l 705.0000 .0347367 706. 0000 .034 7873 701 . 0000 .0148379 708.0000 . 031t8885 709. 0000 .0349390 no.oooo .03lt9896 111.0000 • 0350402 112.0000 .0350908 713.0000 . 0351414 714.0000 .0351919 715.0000 • 035242S 716.0000 .0352931 111 . oooo . 0351437 718.0000 • 035394>3 719.0000 • 0354449 120.0000 • 0354954 121.0000 .0355460 122.0000 .:1355966 723.0000 .0156472 724.0000 . 0356978 725.0000 .0357483• 726.0000 • 0351989 727.0000 • 0358495 728. ooco . 035900\ 729. 0000 • 0359507 730. 0000 .0360013 731.0000 • 0360518 732.0000 . 036 1024 733.0000 .0361530 134.0000 • 0362036 7)5. 0000 740.0000 .0362542 • 03650 71 736. 0000 741.0000 . 0361047 • 0365517 737 . 0000 742 . 0000 .0363551 • 0366082 738.0000 743.0000 .0)6lt059 .0366588 719.0000 744.0000 .0364565 . 0367094 7"5.0000 .0367600 746.0000 .0368106 74 7. 0000 .0368611 748.0000 .0369117 749.0000 .. 0369623 750.0000 .0370129 75 1.0000 .0370635 752. 0000 . 037 11 41 753.0000 .0371646 754 .. 0000 .0372152 755.0000 .0372658 756. 000(1 . 0 37)l64 757 .oooo .0373670 758.0000 .0374175 759.0000 .0374681 760. 0000 .0375187 761.0000 .0375693 762. 0000 .0376199 763.0000 . 0376705 764.0000 • 0377210 765.0000 .0377716 766. 0000 .03113222 767.0000 . 0378728 768.0000 . 0379234 769.0000 .0379739 110. 0000 . 03802.r.5 771. 0000 .0380751 772.0000 . 0381257 773.0000 . 0381763 774. 0000 • 0382269 775.0000 .0382774 776. 0000 . 0383280 777 . 0000 . 0383786 778.0000 . 0384292 779.0000 • 0384796 780.0000 . 0385303 781 . 0000 .0385809 782 . 0000 • 0386315 783.0000 . 0386821 784.0000 . 0387327 785.0000 .0387833 786. 0000 .0)88338 787.0000 . 0388844 788.0000 .0389350 789.0000 • 0389856 790. 0000 . 0390362 791. 0000 .0390867 792. 0000 .0391373 793.0000 .0391879 794.0000 .0392385 795. 0000 • 0392891 796. 0000 . 0393lc,t7 .797. 0000 . 03c,t3902 798.0000 .039lt408 799. 0000 .0394914 TEMPERATURE 20.00 550.0000 .0267266 551.00CO .0267789 552. 0000 .0268292 553.0000 .0268795 554 . 0000 .026-1298 555.0000 • 0269800 556. 0000 • 0270303 55 7. 0000 .0270806 558.0000 .0271309 559.0000 . 0211012 560. 0000 .0272315 56 1. 0000 . 0272818 562. 0000 .0273321 563.0000 .0213823 564.0000 . 0274326 565. 0000 570. oOoo . 0274829 . 0271344 566. 0000 571.0000 . 0275332 • 0217846 567. 0000 572.0000 . 0275835 .0278349 568. 0000 573.0000 . 0276318 .0278852 569. 0000 574. 0000 . 0276841 . 02 7935 5 575.0000 .0279858 576. 0000 .028016l 577.0000 • 0280864 5 78.0000 .. 0281367 579.0000 .028l869 580. 0000 .0282372 581 . 0000 • 02828 75 582.0000 . 0283378 583. 0000 .0283881 584. 0000 . 0284384 585.. 0000 • 028488 7 586. 0000 .0285390 587 .0000 . 0285892 588.oono .0286395 51:39 . 0000 • 02868'18 590.0000 595.0000 600.0000 .0287401 .02A99 15 • 0292430 591. 0000 596. 0000 601. 0COO . 0287904 . 02904l8 • 02112933 592.0000 59 7.0000 602. 0000 . 0288407 .0290921 .0293436 ~91.0000 598. 0000 603.0000 . 0288910 .0291424 .0293938 594 . 0000 59q.oooo 604. 0000 .02894 [3 .0291927 .U29 444l 605.0000 • 02<1lt944 606. 0000 • 029544 7 607. 0000 .0295'150 608.COOO . 0296453 609. 0000 .0296956 610.0000 .02<17459 611 . 0000 . 0297961 612.0000 . 0298464 6 13. 0000 .029896 7 6l4. 0000 • 02994 70 615.0000 .02')99 7 l 616.0000 . 03004"16 617.0000 .. 0300'-179 618.00Cio .0301482 619.0000 .0301984 620.0000 625.0000 .0302487 • 0305002 621 . 0000 626.0000 • 0302990 • 0305505 622 . 0000 627.0000 .0303491 . 0306007 621.00(;0 628.0000 • 0303996 . 0306510 624. 0000 629.0000 .U104499 .0307013 630. 0000 .0307516 631 . 0000 . 03080 19 632. 0000 . 0308522 633.0000 .0309025 634. 0000 • u30'1528 635 . 0000 6 40.. 0000 61t5.0000 650.0000 655.0000 660.0000 665.0000 670.0000 675.0000 680.0000 685.0000 690. 0000 695.0000 . 03l0030 . 03125'i~ .031~059 .031757" • 0320088 • 0322602 . 0325ll 7 .0327631 .0330llt5 .0332660 • 03351 74 • 0331689 . 0340203 636. 0CIOO 641 . 0000 646.0000 65l. 0000 656.0000 661. 0000 666.0000 671.0000 6 76. 0000 681.0000 686.0000 691. 0000 696. 0000 . U3 l05H .0313048 .0315562 .0318076 .0320591 .0323105 • 032562!1 .0328L34 • OH064fj .0333161 .0335677 . 0338191 .0340706 637 .0000 6...2 . 0000 64 7.0000 652. 0000 65 7.0000 662.0000 667.0000 672.0000 t.77.0000 682. 0000 6a 1. 0000 692. 0000 697. 0000 . u3l L036 .0313551 .0316065 .03185 79 . 032 1094 .0323608 .0326122 .. 032863 7 .033 l l 5l . 0333666 . OH6ltW .033tJ694 .0341209 638.COOO 643. 0000 648. 0000 653.0000 656.COOO 663. 0000 666. 0000 673.COOO 678 . 0000 683.0000 688.0000 691.0000 698.0000 .03ll'539 . 0314053 .0316568 .0319082 . 0321597 .0324111 . 0326625 .0329 l40 .03H654 .033'il68 .03366tH .033q197 . 01417 12 6 39. 0000 644. 0000 649.0000 654.0000 659.0000 664. 0000 669. 0000 6 74. 000 0 679.0000 684 . 0000 6a9.oooo 694 . 0000 699. 0000 . 0312042 . 0314556 . 0317071 . 0319585 .0322099 . 03246l'i . 0327128 . 0329643 .0332l57 . 0334671 .0337186 .0339700 .0342214 700. 000(J .03427 17 701.0000 .0343220 102. oooO .0343723 703.0000 ~0344226 704 . 0000 .0344 f29 705.0000 110.0000 .0345232 • 0341746 706. 0000 11 1. 0000 . 031r5·135 .03482lt9 707.0000 112.0000 .0346237 . 0348752 108. 0000 1l3.0000 • 0346 740 . 0 34q25s 109. 0000 714 . 0000 . 0)472 43 . 0349758 715.0000 .0350260 7l6.0000 .0350763 717. 0000 .035 l 266 118. 0000 . 0351169 71 9 . 0000 . 0352272 120.0000 . 0352175 721.0000 • 0353278 122.0000 . 0353781 121 . 0000 .0354283 724 . 0000 . 0354 786 725.0000 .035S289 726. 0000 .0355792 72"1.0000 .0356295 718 . cooo .0356798 729. 0000 . 035 7301 730.0000 .0357804 731.0000 .0358106 732.0000 .0358809 733.0000 .0359312 734 . 0000 . 03598 l S 735~0000 .0360318 736 .. 0000 • 036082 l 737 . 0000 • 0361324 738.0000 .0361 82 7 739. 0000 .0362329 740.0000 .0362812 741. 0000 .. 03£.3335 742.0000 .0363838 743.0000 .036434l 144. 0000 • 03648'ilt 745. 0000 . 036534 7 746 . 0000 . 0365850 747.0000 .0366352 748.0000 .0366855 749.0000 .0367358 750.0000 .0367861 751.0UOO . 0368364 752.0000 • 0368867 753.0000 .036~370 754. 0000 . 0369873 1ss.oapo .. 0370375 756.0000 .0370878 757.0000 .0371381 758. 0000 . 0371884 759 . 0000 .0372387 760. 0000 .0372890 76 l. cooo .0373393 762.0000 .0373896 763 . 0000 .. 0374398 764. 0000 • 0 374901 765. 0000 . 037540lt 766.0000 • 037590 7 767. 0000 . 03764 10 768.0000 .03 76913 769. 0000 . 0377416 770.0000 . 0377919 771. 0000 . ()378422 112.0000 .0378924 773. 00CO . 03 7942 7 774. 0000 • 03 79930 77 5 . 0000 . 0380433 776. ooco .0380936 771. 0000 .Q]8l439 778.0000 .0381942 779 . COOO . 0 382445 780.0000 • 0102q4 1 781.0000 • 038345(1 782 . 0000 .0383953 783.0000 .0384456 784 . 0000 • 0384959 785.0000 . 0385462 786 . 0000 . 0385~65 787. 0000 .0386468 788.0000 . 0166970 789.0000 . 038747 3 790.. 0000 .0387976 791. 0000 • 0388479 792 . 0000 . 0388982 793. 0000 .0389485 794.0000 • 0389988 795.0000 .o:H0491 796.0000 • 0390993 1'11. 0000 .0391496 798.0000 .01q1999 799.0000 . 0392502 464 Changes in Carbon Dioxide Concentration From Changes i'n pH TABLE 3--Continued TEMPERATURE 21.00 550. 0000 .0265607 551. 0000 .0266107 552. 0000 •0266607 55l. OOOO .0267107 554.0000 . 026760 7 555.0000 .0268107 556. 0000 • 0268606 557.UOOO .0269106 558. 0000 . 0269606 559.COOO .0270106 560.0000 • 0270606 56 1. 0000 .0271106 562 . 0000 .0271606 563.0000 .0272106 564 .0000 .0272606 565. 0000 .0273106 566. 0000 .0273606 567. 0000 . 027,,.1 06 568. 0000 . 0274606 569 . 0000 . 0275106 570.0000 . 0275606 571.0000 • 02 76 l 05 572 .0000 . 0276605 573. ouoo . 0217105 574.0000 .U277605 575.0000 .0278105 576.0000 .0278601) s11. 0000 .0279105 578.0000 .02 79605 579.0000 .0280105 580.0000 .Q280605 581 . 0000 .028ll05 582.0000 .0281605 583.0000 .0282105 584.0000 .0282605 585.0000 .0283105 586.0000 • 0263604 587.0000 .. 0284104 588 . CCOO .0284604 589.0000 .o28'H 04 590.0000 .0285604 591. 0000 .0286104 592 . 0000 . 0286604 593.0000 .0287104 594 . 0000 . 028 f604 595.0000 .0288104 596. 0000 • 0288604 59 7. 0000 .028910,. 598.CCOO .0289604 5?9.0000 . 0290104 600. 0000 .0290603 601.0000 • 0291101 602. 0000 .0291603 603.0000 .0292103 604.000U .Q2CJ7.603 605.0000 .0293103 606.0000 • 0293603 607. 0000 . 0294 103 608.0000 . 02'1460l 609.0000 . 0295103 610. 0000 .0295603 611.0000 . 0296103 612 -0000 . 0296603 613. 0000 .0297103 6 14. 0000 • 0297603 615.0000 .0298102 6 16.0000 .0798602 617. 0000 . 0299102 618.0000 .02•19607. 619.000U . 0300 102 6 20. 0000 • 0300602 621. 0000 . 0301102 6Z2 . 0000 .0301602 62'~ . 0000 .0302102 624. 0000 • 0302602 625. 0000 • 0303102 626.0000 • 0303602 '62 7. 0000 . 0304102 628.0000 . 0304602 629. 0000 • 0305102 6)0. 0000 . 0305601 631. 00CO .030610 1 632.0000 .0306601 633.0000 .030710 1 634.0000 .030 7601 635. 0000 . 0308101 636.UUOO .030860 1 637.0000 . 0309101 638. 0000 .0309601 639.0000 . 0310101 6'90.0000 . 031060 1 6'91 . 0000 .01111 01 642 . 0000 .031 1601 643.0000 .0312101 644 .oooo .0312601 645.0000 . 0313100 646. 0000 .03136(10 647. 0000 .0314100 648.0000 .0314600 649. 0000 .03151 00 650.0000 .0315600 651.0000 .0316100 652 . 0000 .0316600 653.00()0 . 0317100 654.0000 .0317600 655.0000 .03 18100 656. 0000 . 0318600 657.0000 . 0319100 658. 0000 .0)19600 659. 0000 .0320099 660. 0000 • 0320599 661 . 0000 .0321099 662. ooou .0321599 663.0000 . 0322099 664 . 0000 .0322599 665.0000 .0323099 666. 0000 .0323599 667. 0000 . 0324099 668.0000 .0324599 669. 0000 -0325099 670.0000 .0325599 6 71. 0000 -0 3260~9 6 72. 0000 . 0326599 673.0000 .03270'19 674.0000 .0327598 675.0000 .0328098 676. 0000 .0328598 677.• 0000 .0329098 678.0000 . 0329598 679. 0000 .0330098 680.0000 .0330598 681.0000 • 0331098 682. 0000 .033 1598 683 . 0000 .0332098 684 .oooo .0332598 685.0000 . 0333098 686. 0000 . 0333598 687.0000 . 0334U98 688. 0000 . 0334598 689. 0000 . 0335097 690. 0000 .0335597 691 . 0000 .0336097 692. 0000 • 0336597 693 . 0000 .033709 7 694 . 0000 .Ol3759 7 695.0000 .0338097 69.6.0000 . 0338597 6-17 . 0000 . 0339097 69A . OOOO . 0339597 699.. 0000 . 0'4009 7 700.000tH.0000 . 027 7565 582 . 0000 .0278059 583 . 0000 .. 0278553 584 . 0000 .0279047 585.0000 . 027954 1 5tS6. 0000 • 0280035 587. coco .li2 80529 588.0000 .0281023 589. ooou .U2815l7 590. 0000 . 02~2011 591. 00UO • 0262505 592. 0000 .0282999 593.000 0 . 0283493 594. 0000 .u28l987 595.0000 .0284'-d2 596.00f:O . 0284976 597 . 0000 .028t.ii470 598. 0000 . 028t.ii964 t.ii99. 0000 .0286458 600. oooc. • U286952 601. 0000 • 028 7446 60?. 0000 .028 7940 603.0000 . 0288434 604. 0000 . LJ21j8928 605. 0000 • 02894 2 2 606. 0000 .02!199 1 6 6U7.0000 .02904 10 608.0000 . 0290904 609 . oouo , 1)29 1 398 610. 0000 • 02918~2 61 1. ccoo .. 0292)136 612. 0000 .0292d80 613 . 0000 .0293374 614.COOO . 0293868 615 . 0000 . 0294362 616.0000 .029 48t.ii6 617.COOO . 029535 1 618.0000 . 0295845 619.0000 • 02963 39 620 . 0000 . ~ 29l83J 62 1 . Ot:OO .0297327 6.22.oOOO . 0297821 623 . 0000 .029 8315 624. 0000 • 0298809 625.0000 . (.. 2~93()3 626 . 000{) .n2':19797 627.0000 . 030029 1 628.COOO . OJ00 7H5 b29 . cooo .03012 79 630. OOOfJ . <>301773 63 1 . 0000 . 0302267 632.00CO .0302 761 633.COOO . 0303255 634. 0000 .0303749 635 . 0000 .0304243 636.0COO .0304737 63 7. coco .03052 31 638.0000 . 0 3 0S7 2 5 639. 0001) . 0306220 640. 0000 : 0306714 64 l . 0000 .0101io8 642. 0000 .0301702 643.0000 .0308 196 644 . 0000 . 0308690 645 . 0000 .03091A4 646 . 0000 • 03096 78 647.0000 .0310172 643 . 0000 .0310666 649 . 0000 . 0311160 650. 0000 . 031165 4 651. UU(JO .031 2148 652 .oooo .0312642 65 3. 0000 .0313136 b54 . 0000 .0313630 655 . 0000 .0314124 656.0000 . 0314618 657.0000 . 0315112 658 . 0000 . 0315606 659. 0000 .031 6100 660.0000 • 03 16595 66 l. 0000 .0317089 662. 0000 .0317~83 663.0000 .0318077 664 . 0000 .0318571 665. 0000 . 0319065 666.. 0000 .031955<:­ 667 . COUO .0320053 668 . 0000 . 032051t 7 66'1. 0000 . 0321041 6 70.0000 . 0321 53 5 671.0000 .0322029 672 . 0000 .0322523 6 7 3.0000 . 032301 7 674 .. 0000 .. 0323511 675.0000 • 0324005 676 . 00UO . 03244CJQ 677 . 0000 • 0324993 678 . 0000 .0325487 6 79. 0000 • 032598 ) 6 80. 0000 • 03264 7 5 681.0000 .0326?69 682. 0000 .032 7464 683.0000 . 0327958 684.0000 .0328452 685.0000 . u 328'146 686 . 0000 .0329440 687 . 0000 .0329':134 688 . 0000 . 0330428 689.0000 .0330922 690 . 0000 . 0331416 691 . 0000 .OB1910 692.0000 .0332404 693.0000 .0332898 694. 0000 . 0333392 695. 0000 • 0333886 696 . 0000 . 0334380 69 7 .oooo .0334874 b98.COOO . 0335368 699. 0000 . 033 5862 100-. 0000 .03363 56 101 .0000 .0'36850 702. 0000 .0337344 703.0000 . 0337838 704 . 0000 . 0338333 705. 0000 .0338827 706 . 0000 .CJB932l 707. 0000 . 0339815 708.0000 • 0340309 709. 0000 .0340803 11 0.0000 . 0341297 711.0000 • 034 1 1'11 7l 2 . 0000 .0342285 713.0000 .034277~ 714. 0000 .0343273 115.0000 . 0341767 716 . 0000 • 0344261 717.0000 .0)44755 718 . 0000 .0345249 719.0000 .0345743 120.0000 • 03462 3 7 12 1 .0000 . 034673l 72 2 . 0000 .0347225 72 3 . 0000 . 0347719 724.0000 . 03'482 1 3 725.0000 • 034870 7 726.0000 .0349202 727.0000 • 0349696 728 . 0000 .01501qo 729.0000 • 03506A4 730. 0000 .035 1178 731.0000 .0351672 732 . oooo .0352166 733.0000 . 0352660 734.0000 . 0353 154 735. 0000 . 0353648 736.0 l l . 0000 • 0290528 612-0000 .029 10 19 613.0000 . 02'H 5 10 614.0000 . 0192001 6 15. 0000 . 0292492 616. cooo • 029298 4 617.COOO • 029 34 75 618 . 0000 .0293966 6 19.0000 .0294457 6 20.0000 .029494C 621.0000 .0295439 622. 0000 . 0295930 623 . 0000 . 0296421 624 .oooo .0296912 625.0000 • 0297 403 1'>26 . ocoo .0297895 627. 0000 .0298386 628.0000 .0298877 629.0000 . 0299368 630. 0000 .0299859 631.0000 . 0300350 632 .. 0000 .03008 4 1 613.0000 . 0301332 634 . 0000 . 030 1823 6 3 5 . 0000 .03023 14 636 . ooco . 0302806 637 . 0000 . 0303297 638.. COOO .0303788 639.0000 . 0304279 61t0 .. 0000 .0304770 641 . 0000 . 0305261 6 4 2. oouo • 0305152 61t3 . 000U .010621t3 61t 4 . 0000 • 0306731t 645. 0000 .0307226 646.0000 • 0107717 647 .. 0000 . 0308208 61t8.0000 . 030869 9 649 .oooo .0309190 650 .. 0000 • 030968 l 651.0000 .0310172 652.0000 .0310663 653 . 0000 . 0311 151t 654 . 000 0 .0311645 655. 0 000 . 0312137 656.0000 .OH2628 657 . 0000 . 0313 11 9 658. 0000 .0313610 659.0000 .0314 101 660.0000 .0314592 661.0000 .03 15083 662. 0000 . 0315574 663.0000 .0316065 664 . 000 0 . 031 6556 6 6 5. 0 000 .0317048 666. 0000 . 0317539 66 7 . 0000 . 0318030 668. cooo . 0318521 669.0000 .O'll 9012 6 70. 0 000 .0319503 6 71 .0000 .0319994 672.0000 . 0320485 673.0000 .032097 6 674.0000 . 0321467 675.0000 .0321959 676.. 0000 .0322450 6 7 7. 0000 . 0322"141 678 . 0000 . 03231t32 6 79 . 0000 .OJ23923 680 .0000 .0324414 681.00UO • 0324905 682. 0000 .0325396 683.0000 . 0325887 684 . 0000 . 03263 79 685.0000 • 0326870 686. 0000 . 0327361 68 7 .0000 . 03278 52 68A . OOOO . 0328343 689.0000 .032B834 690.. 000 0 . 0329325 691.0000 .0329816 692 .. 0000 .0330307 693.0000 • 03 30 7q9 694. 0000 .. 0331290 695. 0000 .0331781 696.0000 . 0132272 697. 0000 .0332763 698. 0000 .. 0333254 699 . 0000 . 0333745 1 0 0 . 0000 .0334236 70 1 .0000 . 0334727 7 02 . oooo . 0335218 703.0000 • 03 35 709 704. 0000 . 0336201 705.0000 • 0336692 706 . 0000 • 033 11 83 70 7 .0000 . 033 7674 708.0000 . 0338 165 709 .oooo . oBa656 710.0000 .0339147 711 . 0000 . 0339638 712.0000 .0340129 713.0000 .0340621 714 . 0000 .. 0341112 715.0000 .034 1603 716. 0000 • 014 2094 717 ­0000 .03425B5 7IA.OOOO .0343076 719. 0000 . 0343561 7 20. 0000 .. 0344058 12 1.0000 .0344549 722 . 0000 .0345040 723 . 0000 .034t.ii5 3l 724 . 0000 . 0346023 7 25.0000 .034651 4 726. ocoo .CJ34'f005 727 . 0000 . 0347496 72R . OOOO . 0347967 729. 0000 .0348418 730. 000D . 0348969 731. 0000 • 0349460 7 32. 0000 .0349951 733 . ooco . 0350443 734.0000 . 0350"34 7 3 5 . 0000 .035 1425 736. 0000 . 0351916 737.0000 . 0352407 738 . 0000 . 0352898 739.0000 . 0353389 H0.0000 . 0353880 741.0000 .0354 3 71 742 .. 0000 • 0354862 743.0000 . 0355354 744 .oooo .0355845 745. 0 0 00 .0356336 746.0000 • 0356827 74 7 . 0000 . 0357 318 74fl . 00(0 . 0357809 749. cooo .0358300 750. 0000 .0358791 751.0000 . 0359282 752 . 0000 . 0359774 753. 0000 . U360]65 754 .oooo .0360756 755. 0000 .0361 2 47 756 . 0000 • 0361 738 757.0000 .0362229 7t.ii8.0000 . 0362720 7S'l.OOOO .0363211 760.0000 • 0363 7Cr2 76 1.. 0000 .0364193 762 . 0000 • 0364685 763.000 0 .0365176 764 . oooo • 036566 7 765.0000 . 0366 1 58 766.0000 .. 0366649 767.0000 .0367140 768 . COOO . O'l67631 769.0000 . 0368122 7 70 .0000 • 0368613 771 . 0000 . 0369 104 772 . 0000 • 03611596 773 . 0000 . 0370087 774.0000 .0370S78 7 7 5 . 000 0 . 0371069 776.0000 .. 0371560 77 7.0000 . 037Z051 178. 00CO .03 72542 779.000U . 03730.H 780. 0000 . 037 3524 78 1.0000 .0374016 782.0000 . 0374507 78}.00()0 .0374'198 784 . 0000 • 0 375489 7 8 5 . 0000 . 0375980 786.. 0000 . 0376471 787 .0000 .. 0376962 788 . 0000 .O'l77453 789.0000 . 0377944 790 . 0 00C .0'3781t35 79 1. 0000 .0378927 7"2 . 0000 .03794 18 793 . 0000 . 0379909 794. 0000 .0380400 795 .00 00 . 0380891 7,6. 0000 .0381382 797.0000 . 03A l 873 798.COCO . 0382.364 799.0000 .0382855 466 Changes in Carbon Dioxide Concentration From Changes in pH T ABLE 3--Continued TE HP ERATl!RE 21. 60 550.0000 . 0258893 551.0000 .0259'.iBl 552 . 0000 .0259869 553.00C:> . 0260357 554.0000 .0260B45 555. 0000 . 0261333 556. OOGO .026 18 2 1 557.0000 .•J262HO 558.000l.l .026 2798 559 . 000lJ .0263286 560. 0000 .. 0263174 ';61 . 0000 . 02642 62 'j62 . 0000 .IJ2647 50 563 . 0000 . 02652)q 564 .oooo .0265727 565 . 00 00 . 0266215 566. 0000 • 0266 703 567. 0000 .0267 191 568.0000 .02676 79 569.000 0 .0268 168 570.0000 • 0268656 571 . 0000 .0269144 572. 0000 . 026~632 573.0000 .027 0 120 574. 0000 . 0270608 575. 0000 . 0271097 576 . 000 0 • 0271585 577 . 0000 .0272073 57A . OOOO . 0272561 579.0000 .0273049 580. 0000 . 027353 7 581.0000 -.0274025 5B2.0000 .0274S l4 583 . CCCO . 0275002 584.COOO . 02 75 490 585 . 00 00 . 0275978 586 . 0000 • 0276466 587.0000 .0276-154 588 . 0000 . 02774'43 5B9.0000 . 0 2 17911 590 . 0000 .02184 19 591 . 0000 .0278907 592 . 0000 .0279395 593.0000 .02798B3 594. cooo .U280372 595 . 0000 • 0280860 596.0000 .0281348 597 .OOCJO .021:11836 598.0UO(J .0282324 59Q.COOO . 0 7.82812 600.00 0 0 .028 3301 60 1.0000 . 0283789 602 . cooo . 02842 7 7 603 . 00CI) . 0284765 604. 0000 .0185 253 605 . 0000 . 028 5741 606. 0000 • 0286229 607. 0000 .02861 18 608 . 0000 . u2877.06 609 .oooo .02e7694 6 10. 000 0 . 0288 182 611 . 0000 .02886 70 612 . 0000 .02tPH58 613.0000 . 0 289647 614.COOO .0290135 61 5 . 0000 . 0290623 616. 0000 .0291111 617. 0000 . 029 1599 61'1.0000 .0292087 619.0000 .07.92576 620. 0000 • 0293064 621 . 0000 . 0293552 622.0000 . 0294040 62 ) . 000 0 . 0294528 624. 0000 . 02950 16 b25.0000 .0295505 626.0000 • 0295993 627. 0000 .0296481 628 . 0000 . 0296969 629 . COOo . 0297457 6 30 . 0000 . 0297945 63 1.. 0000 .0298433 632 . ooou .0298922 633.00CO . 02994 10 634 . 0000 • 0 299898 635.0000 • 0300386 636.. 0000 .0300874 637 . 0000 .030 1362 638.COOO .0301851 639 . 000U . 0302339 640 . 0000 • 0302827 6'4 1 .0000 • 0303315 6'42."0000 . 0 30380 3 6" 3.00 00 . 0)0'4291 644 . oooo .0104780 64S. OOOO • 0305268 646. 0 000 .0305756 64 7 . o ooo .03062"" 6"8 . 000 0 .0306732 649 . 0000 .0307220 650.0000 • 0 301709 65 1.0000 • 03081 97 6 52 . 0000 .0308685 653. 0 00U .030917 3 654 .0000 . 0309t..6l 655. 0000 .. 0310149 6 56 . 0000 . 0310638 657.0000 . 03 11126 658. 0000 .0311614 659. 0000 . 0112102 660 . 0000 .03 12590 66 1 . 0COO • 0313078 662 .0000 . 0313566 663 .0000 . 0314055 66" . 0000 . IJll.4'>43 66 5.. 0000 . 0 3 15031 666. 0000 .0315519 667 . 0 000 .0316007 661t . OCOU .03 16495 66'4.0000 . 03161-i84 6 70.0000 . 031 7't 72 671 . 000 0 . 0 31 796 0 612. 0000 • Oll8't 48 613.0000 .03 18936 674 . 0000 . 0 11 9424 6 75 .0000 .0319913 6 76 . 0000 .03 20401 6 77. 0000 .0)20889 67H . 0000 . 032 1377 67q.oooo . 032 1865 6 8 0. 0000 . 0322353 681.00CO . 0322lf42 682.0000 . 032 3330 683 . COC O . 0 3 2 38 18 684.0IJOU .0124rn6 6 85.0000 . 0324794 686 . 0000 . 0325282 687 . 0000 . 0325770 68H.0000 . 032i', 2 59 689 . 000 (1 . 0326 147 6 9 0. 0000 6 95.0000 . 0327235 .. 0329676 691. 0000 b96.. 0000 .. 0327723 .0330164 692 . 0000 69 7.0000 .03282)1 .03306 52 69.J.CCOO 69& .oouo . 0328699 .0331140 6"11t . 0000 t.."1'4.0UOO . 03l91.88 .uHl 62H 700. 0000 .033211 7 701.0000 .0332605 702.0000 .0133093 701 . 0000 .03 33'>81 704 .0001) . 0 114069 705.0000 .033'9 55 7 706.. 0000 . 0335046 707 . 0000 .03355 3" 708.0000 .0336022 709 . 0000 .uH6510 110. 0000 • 0336998 11 1. 0000 .0337486 712 . 0001) . 0 337974 713 .cooo . 0338463 714.01100 . 0338951 715. 0000 . 0339'439 716.. 0000 .0339927 111.0000 . 0 3'4041 5 718 . 0000 . 0340903 7 19.COOO .0341392 7 20 . 00 00 .034 1880 72 1.. CJ OOO .0342368 722.0000 .03428 56 123.0000 . 03433l0..ft 724 . oooo .ol43tn2 7 25. 00 00 . 034't321 7 26.0000 • 03't4809 727 . 00110 . 03't52q7 728 . 0000 .0345785 729.COCC . 0 346213 730 . 0 00 0 .034676 1 731 . 000() .0347250 732.0000 . 0347738 731 . 0000 .. 0348226 734.0000 • 0 34B 1tl0 735. 0000 .0349202 736. 0000 • 0349690 737.0000 . 0350 178 138.0000 . 035066 7 73q.oooo . 0351155 740 .0000 .03516lt3 741 . 000 0 . 0352131 7'42.0000 . 0 35261'1 74 3 . 0000 . 03';3 107 7lt4.0000 .0353596 7lt5.0000 .0354084 746. 0000 .0354572 747.0000 . 0355060 748.0000 .. 035554 8 749.COOO . 0156016 750. 00 00 .0356 525 75 1.0000 .0357013 752.0000 .. 0 357501 753.00CO . 03571189 754.000 0 • U)584 71 755. 0000 .0358965 756.0000 • 0359454 751 . 0000 .0351194 2 758 . 0000 . 0360430 759.000iJ . 0360916 760 . 0000 . Q36 1406 761.0000 .036 1894 762. 0000 .0362382 763 .. oono . 016287 1 764 . cooo . 0361359 765.0000 • 036 384 7 766.0000 .0364335 76 7 .0000 . Ol61t823 768.0000 . 0165ll l 76?.0000 .Ol651t00 7 70.00 00 .0366288 771. 0000 • 03667 76 112.0000 . 036 7264 771.0000 .0367752 774 .. 0000 • 0368240 775.0000 . 0 368729 776. 0000 .0369217 111.0000 .0')69705 778.0000 .0170193 779. COOO .0370681 780. 0 000 .0371169 78 1.0000 .0371658 782 . 0000 . 03721 4 6 783 . 0000 . 0171614 764.0000 .0373122 7 85.. 0000 1qo.oooo . 0373610 .0376051 7lf6. 0000 791.0000 . 0374098 . 03 76539 78 7.0000 792 . oooo .0374 58 6 .. 0377027 7 88.0000 7q3 . oooo .en 15015 .0177515 789.doou 194 . 0000 .. 0375563 .0378004 795. 0000 .0378492 796.0000 • 0378980 797 . 0000 . 0379468 798 . 0000 .0379956 799 .oooo .03804 44 TE MPER ATURE 22.00 550. 000 0 .02572 15 551.0000 .025 7 700 552 . 0000 .02•~1 85 553.00t:O .0258670 554.0000 . 0259156 55 5.0000 . 0 25964 l 5 56. 0000 .0260 1 26 55 7. cooo . 0260611 558. 0000 .0261097 559.0000 . 026 1582 56 0.0000 • 026206 7 5.6 1. c.. c oo • 0 262552 562.0000 .0263017 563.0000 . 0263523 564 . 0000 • 0264008 5 65. 000 0 .0264493 566 . 0000 .0264978 567 . 0000 .0265464 568. OOCIO .0265949 569 . 0000 . 07.66 434 5 70.0000 • 026t.9 l 9 571 . 0000 • 0267404 !>72. 0 000 . 026 7890 5 73.. 0000 .0268315 5 74. ouou .026d860 575.0000 . 026q345 5 76.0000 • 0269830 517 . 0000 .. 0270316 5 78. 0 000 .0270801 579.COOO . U2712tl6 s00 .oooo .027177 1 5Bl . OOOO .0272257 582 . 0000 . 02727'92 583 . 0000 .0273227 584 . 0000 . 0211112 5 8 5 .0000 . 027419 7 586 . 0000 • 0274683 587 . 0000 . 027516 8 588.0000 .. 02 75653 'i89 . 0000 .0176 138 590. 0000 .0276624 591 . 0000 .. 027 7109 5'i2. 0000 . 0277594 593.. 0 Q(jO .. 0278079 '>94.0000 . 0278564 595. 0000 .0279050 596 .. 0000 .0279535 597.0000 .0290 020 598.0000 .0280505 599.000 0 . 02 80990 600.00 00 . 0281476 601 . 0000 . 0281961 602 . 0000 .02824'46 603.0000 . 0282931 604.0000 .. 078 141 7 60 5.0000 .. 0283902 606 . ocoo . 0 284387 607 . oooo .0284872 608. 0000 .028535 7 609.0000 . 028 5843 610. 0000 .0286328 6 11. 0000 • 0286813 6 12.0000 . 02e12qe 613. 00CO .028778 4 614 . 0000 . 0288269 6 15 .0000 . 0288754 616.0COO • 02892 39 617.0000 .. 0289724 618.0000 .. 029021 0 6 19 . 000 0 • 0290695 6 20.0000 .0291180 62 1. 0000 . 0291665 622. 0000 . 0292151 623.0000 .02q2636 624 .. 000 0 . 0293 l 2l 6 2 5. 0 000 • 02q1606 626.. 0000 .0294091 627.0000 .. 029 4 5 77 628.00 00 .02 95062 629.0000 .0295547 6 3 0.0000 . 02q6012 631 . ocoo • 0296517 632 .oooo . 029700 3 633 . 0000 . 02974 88 634.000 0 • 0297973 635. 0000 .0298458 6 36. 00()0 • 0298-144 63 7.. 0000 .0299429 638.00CO . 0299914 639. 0000 • 030019':' 640~0o0o • 0300884 641·.oooo .0301370 642 .oooo .0301855 6 '9 3. 0 000 .0302340 64" .ooo o .0302825 645 . 0000 .030331 1 646.0000 . 0303796 6 4 7 .0000 . 0304 281 64B.OOOO .. 0 304766 649 .0000 .. 0 30 525 1 65 0 . 0000 .030S737 65 1.. 0000 .0306222 652 . oooo . 030670 7 653 . 00 0 0 . 0307192 6 5". 0000 .0307677 6 5 5. 0000 .. 0 308161 656.. 0000 . 0308648 65 7. 0 000 . 03091 33 6 58 . 00 00 .030961 8 6 59.. 0000 .. 031010..ft 660.0000 . 0310589 661. 0000 . 03 11 074 662.0000 .0311 5 59 663. 0000 .03120"4 664 . 0000 .0312530 665. 000 0 .0313015 666. 0000 . 0313500 667.0000 .0313985 6 68. 0 000 .031"471 669. 0000 .. 0 314956 6 70. 0000 .0315441 6 71 .0000 . 031~926 672 .0000 . 0 316411 6 7 3.0000 .. 0316897 674.000 0 .031 73 82 6 75. 0000 . 0317867 6 76. 0000 .0318352 677.0000 .03188 3 7 678 .00 0 0 .0319 323 679 .0000 .031 9808 680.0000 6 8 5. 0000 .0320293 .032 2719 681.0000 686. 00 00 • 0320778 .0323204 6B2. 0000 687. 0000 . 0 32126 4 .03236 90 683.00 00 688 . 00 00 .. 012 1 74q .03 241 75 684 . 0000 689.0ooo .. 0 32 2234 . 032"660 690. 0000 .0325145 691.0000 .0325631 692.000 0 . 0326116 693.0000 .. 0 3 2660 1 694 . o Ooo . 0317086 695. 0000 .0327571 696 . 0000 . 0328057 6cn . oooo .03285"2 698. (lO OO . 0329027 6 9q.oooo : 0 329512 70 0. 0 000 .032999 7 10 1. 0000 .0330't83 702. 0000 .0330 968 70 3 . 0000 .. 0 3 31 453 704. 0000 . 0331q39 705. 0000 .033242 4 706.0000 • 033290~ 707. 0 000 .• 0333 394 708. COOO . 033387q 709.0000 • 0334364 11 0 . 0000 n•.oooo • 03348 50 .0337276 1 11. 0000 7 16. 0000 . 0335335 . 0337761 712 . 0000 717 .OOOoo • 0362022 767 . 0000 .036250 7 768 .oooo ..0362992 769 .0000 • 0 36 34 78 770. 0 000 .0363963 771 .. 0000 • 0364448 712.0000 . 0 36 lt933 773 . 0000 . 03654 18 7 74 . 0000 .0365qo" 775.. 0000 . 0366389 776. 0000 . 0366874 7 77.0000 .0367359 77 8.0000 .036784'9 7 79 .0000 • 0368330 780.0000 .0368815 781.0000 • 0369)00 782.0000 . 0369785 783. 0000 .0370 271 784.000 0 .03"707 56 785.0000 . 037124 1 786.0000 .0371 726 78 7 .0000 . 0372211 788. 0000 .01726 9 7 7 89 . 0000 . 0173182 190 . 0000 . 037 3667 791. 0 000 .0374 152 1q2.oooo .0374638 793. 00 00 . 03 75 l 23 794. 000 0 .0375608 79 5.0000 . 03760.9 3 796.0000 .0376578 79 7 . 0000 .0377064 798. CCOO . 0 377549 799. 0000 .0378034 Changes in Carbon DioxUle Concentration From Changes in pH TABLE 3-Continued TEMPERATURE 22.20 550.0000 -0255537 55 1.0tlOO .02~6019 552 .0000 .0256502 553.0000 .OZ56981t 551t .oooo .0257466 555.000 0 .0257949 556 . 0000 .025B43l 557 . 0000 • 0258911 558.0000 .0259395 559. 0000 .0259ti78 560.0000 • 0260360 561. 0000 • 0260842 562.UOOO . 0261325 563.00CO . 026 1807 564 .oooo .0262289 565.0000 .0262771 566.0000 • 0263254 S6 7. 0000 . 0261736 568.00CO .0264218 '569.0000 .0264700 570.0000 . 0265183 571. 0000 • 0265665 572.COOO . 0266147 573 . 0000 .0266630 514. 0000 . 0267112 575.0000 .0267594 576.0UOO • 0268076 577.0000 . 0268559 578.0000 • 0269041 5 79. 0000 .0269S23 seo. oooo 5 85. 0000 .0270005 .02724l7 su.oooo 586. 0000 • 02 /0488 .0272899 582. 0000 587. 0000 .0270970 .0273381 583. 0000 588.00CO .0271452 .02 73864 584.0000 589. 0000 .0271935 . 0274346 590.. 000C .02 7't8 28 591. 0000 . 0275310 592.0000 .02 75793 593.0000 .0276275 594. 0000 .0276757 595. 0000 . 0277240 596. 0000 .0277722 597. 0000 .02 78204 598 . CCQO .027A686 599. 0000 . 0279 169 600.0000 . 0279651 601. 0000 .07.80133 602.COOO .0280616 603.00CO .028109A 604. cooo .0281580 6 0 5 . 0000 .0282062 606. ocoo • 0282545 607. cooo . 02113027 608. 0000 .028350084 633 . OOlJO .0295566 634.0000 .02960.C.8 635.0000 . C29b531 636 . 0000 .0297013 637.0000 • 029 7495 638 . 0000 .0297977 639. 0000 • 0298.C.bO 640. 0000 • . 0198942 641 . coco • 02119424 642.0000 • 0299907 643. 0000 .0300389 644. 0000 .03008 71 645.0000 . 0301153 646. 0000 .030 183b b4 7 . 0000 .0102 -H8 648.0000 . 0302800 649.0000 . 0303282 650. 0000 . (J30J7b5 651.0000 .0304241 652.0000 .0304729 65!1.0000 . 0305212 654 . oooo .0305691t 655.0000 . 0 3061 76 656.0000 • 0306658 657.0000 . 0307141 6"iR.COOO .0307623 659.0000 .0308 105 660. 0000 • 03085d8 661. 0000 . o30"J0 70 661. 0000 . 03095 52 663. 0000 .0310034 664 . 0000 .03l0517 665. 0000 -0310999 6b6.00()0 .0311481 66 7.oooo .0311963 66tJ. 0000 .0312446 6b9 . 0000 .0312928 6 70.0000 .031 3410 671.0000 .03 1381J3 672.0000 .0314375 673 . 0000 . 0311t857 67't.OOOO . 03 15339 6 7 5 . 0000 .0315822 6 76. 0000 • 0316304 617 . 0000 . 0316186 67a.oooo .0317268 679 . 0000 .0317751 6 80.0000 .0318233 681.0UOO .0318115 682 . 0000 .0319198 683.0000 .03 19680 681t.OOOO .0320162 6 85.0000 • 0320644 686. tJOOO .0321127 68 7. 0000 . 0321609 688. 0000 .032?091 689 . 0000 .0322513 690.0000 .0323056 691. 0000 .0323538 692 . 0000 • 0324020 6'13.0000 .0324503 691t.OOOO • 0314985 6 95.0000 • 0325461 646.lJUOO .. 0325•"49 697 . 0000 . 0326432 6'1f!.COOO . 03269 14 699 . 0000 . 0327396 1 0 0 . 0000 .032787~ 101.0000 • 032836 1 702. 0000 . 0328843 703.0000 . 0329325 704.0000 • 0329808 705. ooou .03302110 706.0000 .0330772 707. 0000 .0331254 708.0000 . 0331737 709 .oooo . 0332219 110.0000 .0332701 111.0000 . 033318'1 112.0000 . 0333666 713.0000 .0334148 7l't.0000 .0334630 71 5.0000 120.0000 .0335llj .0337524 716.0000 721.0000 • 0335595 .0338006 71 7. 0000 722.0000 . 033607 7 .0338489 7l 8 . 0000 723 . 0000 .. 0336559 .0338971 719.0000 724.0000 • 03) 7042 . 0339453 725.0000 .0339'135 726.0000 .034041R 72 7 . 0000 • 034 0900 728.0000 .03'11382 729.0000 . 0341 865 n o.oooo .0342347 731.0000 .G342A29 732.0000 . 0343311 733.0000 • 0343794 734 . 0000 .03'1 4276 7 3 5 . 000C . 0 344758 736.0000 . 03452.C.O 737.0000 . 0345723 738.0000 .0346205 739 . 0000 . 0346687 71tO .. 0000 . 0347170 7'11.0000 . 0347651 74 2 . 0000 .0348131t 743.000 0 . 0348616 744 . 0000 • 031t9099 745.0000 .. 0349581 746 . 0000 . 0350063 747 . 0000 . 0350545 71t8.0000 .0351028 749.0000 . 0 3 5 1510 750 .0000 .0351992 751.0000 .0352475 752. 0000 . 0352957 753 . 0029 567.0000 . 0262008 568.COOO .. 0262488 569.0000 .. 0262967 570. 0 000 . 0263446 571.0000 • U2b3926 572.0000 .0261t405 573.0000 .026488.C. 574.0000 • 0265364 575.0000 . 0265843 5 76. 0000 .02b6322 577.0UUO . 02b6802 5 78. 0000 .0267 28 1 579.0000 .. 0267760 580.0000 .0268240 5& 1 . 0000 .0268719 S82.oooo .0269198 583.0000 .0269678 581t. 0000 .0270157 585. 0 000 • 0270636 586. COOO . 027lll6 587.00CO .027 1 595 588. 0000 . 0272074 589.0000 . 0272554 590 . 0000 .0173033 591. 0000 .0273512 592 . oouo . 0273'i92 593 . 0000 . 02741t71 59.C..0000 • 0214950 595.ooou . 0275.C.30 596. 0000 • 02 759G9 597. 0000 . 0276388 '>9&.0000 .0276868 599.0000 • 02173.C. 7 600 . 0000 .02771:126 60 1 . 0000 • 0278306 &02.0000 • 0278 785 603 .oouo .027926 .C. 604.0000 .0279744 6 0 5 . 0000 . 0280223 606 . 0000 • 0280702 607. 0000 . 0281182 608.0000 .0281661 609 .. 0000 .0282\ltO 6 10.0000 .0282620 6 1 1. 0000 . 0283099 612 . 0000 .0283578 613 . 0000 .0284058 6l't.OOOO .028.C. 537 6 15.0000 . 0285016 616. 0000 • 0285496 617.0000 .0285975 618 . 0000 .0286 454 6 19.0000 • 0286931t 62 0 . 000 0 .. 0287413 621.00GO • 0287892 622 . 0000 .0288 372 &23.0000 .0288851 621t . OOOO .028"il330 625 . 0000 . 0189810 626. 0000 .0290289 62 7. 0000 .0290 768 628.0000 .02912.C.8 629. 0000 . 0291727 630.. 0000 • 0292206 631.00UO • 0292686 632 . 0000 . 0293165 633.0000 . 0293644 634.0000 .0294124 6 35 . 0000 .029'1603 636.0000 • 0295082 63 7.oooo • 0295562 613.0000 • 029b041 639 . 0000 • 0296520 blt0. 0000 • U2'17000 641 . 0UOO .0297419 642. oooo .0297958 643.000 0 .0298'138 61t4.0000 .02989 17 645.0000 • 029939b 6.C.6. 0000 .02'il9876 647.0000 .0300355 648 . 0 000 . 030083.ft 649. 0000 .. 030l 3llt 6 50. 0000 .0301793 651. UU,lO .0302272 l..52 . 0000 .0102 ·1s2 653.0000 . 0301231 651t.OOOO . 0303710 655.0000 . 0304190 656 . (IQIJU • 030't669 657.0000 . UlU5l4A 6"ift . 0000 .0305b28 b59. 0000 • 03061 Ol 660 . 0000 .0306586 661.0000 • 0307066 662 . 0000 . 0307545 661.0000 .0308014 661t. 0000 • 0308504 665. 0000 .0308983 666. 0000 • 0309462 66 7. 0000 . 030994 2 668 .0000 .0310421 b69. 0 000 .0310900 6 70. 0000 .03113tt0 671.0000 .0311859 6 72. 0000 .0312338 673.0000 .0312818 67" . 0000 . 0313291 6 75. 0 000 .0313776 6 76. 0000 .03llt25b 677.0000 .0314735 678 . 0000 .0315214 679.0000 . 0315694 680 . 0000 .. 0316173 681. 0000 .0316652 682 . 0000 .0317132 683.CCOO .03176 1 l 684 . oooo .0318090 685. 0 0 00 .0318570 686.0000 . 0319049 687. 0000 • 0319528 688.0000 . 0320008 689. 0000 .0320487 690 . 0000 6 9 5.0000 • 032 0'166 . 0323363 691 . 0000 696. 0000 .0121446 .0)2384l 692 . 0000 697.0000 .0321'125 . 0324322 693 . 0000 698 . coco . 0322404 . 0324801 694. 0000 6CJCJ . oooo . 0322t!8<\ • 01252•0 700. 0 0 0(J .0325760 701. 0000 .0326239 702. 0000 .0326118 703.0000 .0327l98 70'1 . 0000 • 0 32 7 6'77 705. 0 0 00 . 0328 156 706 . 0000 • 0328b36 707. 0000 .03291 15 708.0000 .0329594 709 . 0000 . 033007" 710. 0000 .0330553 7 11. 0000 . 013 1032 7 12.0000 . 033 1512 713.0000 .033 1-191 714 . 0000 .0332470 71 5.0000 12 0 .0000 . 0332950 . Q.335346 716.0000 1 21.0000 .0333429 .0335b26 71 7. 0000 122.0000 .0333908 .0336305 718.COOO 723.0000 .0]34388 ;03 36784 719. 0000 724 . 0000 .0334867 .0337264 725. 0000 .03377'13 72b. 0000 .0338222 72 7 .0000 .0338702 728.0000 . 0 339181 729.0000 • 0319660 7 30.00 00 . 0340140 731.00 00 • 0340619 732 . 0000 .0341098 733.00CO .0341578 734 .0000 • 0342057 735.0000 . 03'12536 73b. 0000 . 0343016 737. coco .0343495 738. ooco .034B74 . 739 . 0000 • 0344454 740. 0000 .0344933 741. 00<10 • 03454 l 2 742.00CO • 0345892 743 . 0000 .0146371 74.C.. 0000 .0346850 71t5 . 0000 .03it7330 746 . 0000 .0347809 747 .0000 . 03482:88 748.COOO .0348768 749 . 0000 • 0349241 750 . 0000 . 0349726 751 . 0000 .0350206 752.0000 .035068 5 753.0000 .015 1164 754 . 0000 .035 164.C. 75 5.0000 . 0352123 75b.OOOO .0352602 75 7 . 0000 .0353082 758 . 0000 .0353'>61 759 . 0000 .0354040 76 0. 0000 .0351t520 761. 0000 . 0354999 762 . 0000 .0355478 763.0000 .0355958 764 . 0000 .0356437 765. 0000 .0356916 766. 0000 .0357396 761 .COOO .0357&75 768 . 0000 .0358354 769.0000 • 0358831t 11 0. 0000 • 0359313 111. 0000 .0359792 112.0000 .0360272 773 . 0000 .0360751 774 . 0000 .036 1230 775 .ooOo . 0361710 7 76.0000 .0362189 111 . 0000 .0362668 7 78.0000 .0363148 779 .. 0000 .0363627 780. 0000 .0364 106 78 1 .0000 .0364586 782. 0000 .0365065 783.00CO .. 0365544 784.0000 • 0366024 7 85.0000 .0366503 786.. 0000 .0366982 787.0000 .0367"62 788.0000 . 0367941 789 .oooo . 0368.C. 20 190.0000 • 0368900 791.0000 .0369379 792. 0000 . 03b9858 793.0000 . 0370338 79.C. .oooo .0370 817 1 9 5. 000 0 .0371 296 796.0000 . 0371776 797. oono .0172255 798.CCCO .0372734 799.0000 . 037321.ft Changes in Carbon Dioxide Concentration From Changes in pH TABLE J-Continued TEM PERATURE 22 .•o 550. 0000 .02521 82 551.0000 • 0252b59 552 . 0000 . 025 3135 553 . 00CO . 0253bll 5 54.0000 • 02 54088 555. 0000 .O Z5456 4 5 56. 0 000 .0255041 5 57 . 000 0 .025551 7 558 . -0000 . 0255993 559 . 0000 . 02564 70 560 . 0000 .0256 9 1t6 561.0000 .0257423 562 . 0 00 0 . 0257899 563 .0000 .0258 375 5 6 4 . 0000 . 0258852 565.. 00 00 • 025932 8 566. 0000 • 0259804 567 .0000 .026028 1 568.0000 .026075 7 569 .COOO . 02612'.H 5 7 0.000 0 . 0261710 5 71 . 0000 . 026 2186 5 72.000 0 . 0262663 5 73.00 00 .0263139 57.ft.0000 .0263616 515.0000 • 0264092 5 76 .0000 • 026 4568 5 77. 0000 . 0 265045 5 78. 0000 .026552 1 579.0000 .0?65998 5 80. 0000 . 0266471t 581 . 0000 • 0 266950 582. 0000 .0267427 583. 0000 .0267903 58~.oooo . 0268380 585. 0000 . 0268856 586. 0000 . 0269332 587.0000 . 0269809 588 .0000 .02 70285 51:19 . 0000 .0270 762 590. 0 000 . 0271 238 591.. 0000 . 02717 14 592. 0000 . 0272191 593.0000 ·. 0272667 594 .0000 .U27ll43 595.0000 . 0 2 736 20 596. 0000 .0274096 597 .0000 . 0274573 598 . 0000 .0275049 ·.599.0000 .0275525 600. 0000 . 0276002 601 . cooo • 02764 78 602 . o oo o . 0276955 603. 0 000 .c2 774 31 604 . 0000 .0277907 605.0000 . 027 8384 606.0000 .0278860 607 . 0 000 .02 79 3 11 6 0 8 . ooco . 02798 1 1 609 . 0000 . U280289 6 10. 0000 . 0 28076 6 611 .0000 • 028 1242 6 12 . 0000 .0281719 613.0000 .0282195 614 .OOOCJ • 07826 71 615.0000 . 028 3148 6 16.0000 .0283624 617. 0 000 .028 "100 6 18 .0000 .0284577 619.0000 . 0785053 620.0000 . 028 553 0 •21.0000 • 0286006 622.0000 . 0286~82 6 23 .0000 . 0286959 624 .oooo • 0287435 6 2 5. 0000 . 0287912 626.0000 • 0288388 627. 0000 .02 88864 628. 0 000 • 028934 1 629.COOO .0289817 6 30.0000 . 0290 294 631. 0000 . 0290770 632 . 0 000 . 029 12.ft6 6 3 3 . 0000 . 0 291723 634 . cooo .0292199 b 35. 000 0 . 0292676 636. cooo .0293 152 63 7. COOO • 029362 8 6 3 8 . 0000 .0294 105 639.0000 • 0294581 6 40 . 0000 • 02950S 7 6 41. 0000 • 0295514 642 . 0000 .02960 10 64 3 .0000 .02 9648 7 644 . 0000 • 0296 963 6 4 5 . 00 00 .0297439 61t6.0000 .0297916 64 7. 0000 • 029839 2 61t 8 . 0000 .0298869 649 . 0000 . 0299345 650 .. 0000 • 0299821 6 51. 0000 .0300298 652.0000 ~ 0300774 6 53.000 0 . 0301251 654 . oooo . 0301727 655 . 0 000 .0302203 656.0000 . 0 302680 657.0000 . 0303156 658 . 0000 . 0303633 659.0000 . 0304109 6 6 0 .. 00 00 • 030458 5 6 61 . 0 000 • 0305062 662 .oooo .03055)8 663 .0000 .. 0306 0 14 664 . ooo o . 030649 1 6 6 5 .0000 • 030696 7 666 . 0000 . 030 7444 667.0000 .0307920 668.0000 ·. 030839 6 669 . 0000 .0308873 6 70 . 0000 .030934 9 6 71 .0000 • 03 09826 6 72.0000 . 0310302 6 73 .000 0 . 03 10778 674.0 000 . 0311255 675. 0000 .03 11 7)1 6 76. 0000 . 0312208 677.0000 .0312684 6 78.00 0 0 .. 0 ) 1316 0 67'1.0000 .0311631 680.000 0 .03141 1 3 6 81. 0000 . 031 4590 682 . 0000 .0315066 683 .0000 .03155't2 681t.COOO .0316 01'1 685. 0 000 .03164'15 6 86. 0000 . 0316971 687.0000 .0317448 688 . COO O .. 0 31 792 4 689 . 0000 .0318401 690. 0000 .0318877 691. 0 000 . 0319353 6 92 .0000 .OJl'JtUO 693 . 0000 .0320306 694 .0000 . 0320783 695. 0000 . 0 32 1259 696. 0000 • 037. l 735 697. 0000 . 0322212 698 .0000 .0322688_ 699 . oooo .0323165 1 0 0 . 0000 .032364 1 701. 0000 .0321tl l 7 702 .0000 .0324591t 703 . 0000 .032507 0 704 . 0000 . 0325547 70 5. 0000 • 032602 3 706. 0000 . Ol26499 707 .0000 .0326976 70$. 0000 .0327452 709. 0000 .0327928 110.0000 • 0328405 711.0000 . 0 328881 112.0000 • 0 329358 71 3 . 0 000 .0329834 714 . 0000 .0330310 7 15 . 000 0 .0330787 -716.0000 • 033 12 6 3 71 7 .0000 . OH I H O 7 18. ClO OO .0332216 719.0000 . 0312692 720. 0000 . 0333 169 12 1.0000 . 033361t5 722.0000 .03Jit l 22 723.0000 .0331t598 .12.c, . 0000 .033507" 725. 0000 . 0)35551 726.0000 .033602 7 727. 0000 .0336 501t 728.0000 . 0 3 36 9 8 0 129. 0000 . 03374 56 730. 0000 .0337933 731.C:OOO • 0338409 732.0000 .0338885 7"33. 0000 . 0 339 362 7 34 . 0000 . 03398 38 7 35.0000 .0340315 7J6. 0000 . 03407Q l 737 . 0000 . 0 34126 7 738 .0000 . OJ'tl 744 HCJ . 0000 . 0342220 740. 0000 . 0342697 74 1. ouoo . 0343173 742.0000 .034361t9 7.\3. 0000 . 03.\41 26 744 .ooon • 0344602 745.000 0 . 0345079 71t6. 0000 • 0345555 74 7. 0000 . 031t603 l 74 8.0000 . 0 3465 0 8 749.0000 . 01"6984 750. 0000 . 034 7461 75 1. 0000 . 0347937 752 .oooo . 0 348"13 75 3 .00 00 . 0 3lt8890 7 54 . 0000 • 0349366 755. 0000 .0349843 756.0000 . 03503 19 757 . 0000 . 0350795 75 8.0000 . 0 351272 759.000{) . 0151 748 760.000 0 . 0 352224 76 1 .0COO . 035270 1 762 . 0000 . 0353177 763 . 0 0 00 . 0 353654 764 . 0000 . 0354130 765 .0000 . 0 354606 766. 0000 . 0355083 767.0000 . 03555 59 76 11 . 0000 . 0156 036 769.0000 .0)56512 1 10. 00 00 .0356988 771 . 0000 .0157465 772.0000 . 035794 1 773.0000 . 0 358 41 8 7 74 .oooo . 0358894 7 75. 0000 . 0359370 776 .0000 • 0359b4 7 7 77.0000 . 0360323 778 . 0000 . 0360800 779.0000 .036 1276 780 . 00 0 0 . o-361752 7 81 .0000 .0362229 7 82.0COO • 0362705 7 83.0000 .03631 81 784 . 0000 • 0163658 785. 000 0 .036 4134 786.0000 .0364611 78 7 .COOO .036508 7 788. 0000 .03~5563 789.0000 .o 366040 790.0000 . 0)66516 791. 0000 • 0366993 792. 0000 .0367469 793 . 0000 . 016794 5 794.0000 .0168422 79 5 .0000 .0368898 796. 0000 .0369375 7q7 .oooo .0369851 798 . 00CO . 0370327 799.0000 • 03 70804 TEM PERATURE 22 . 80 5 50.000 0 • 0250501t 55 1.0000 .0250978 552 . 0000 .0251'.51 553.0000 . 0251925 554.0000 . 0252398 555. 0000 . 02528 72 556. 0000 • 0253345 557.0000 .025"lbl9 558.0000 . 0154292 559.0000 .0254 r66 560. 0000 . 02 55239 561. 000 0 .0255 712 562. 0000 . 0256186 563 . 0000 .0256659 561t .oooo .UZS7133 565. 0000 . 0257606 566. 0000 . 0258080 567.0000 .0258553 568 . 0000 .025902 7 569.0000 • 025-1500 570. 0000 .025 9973 571.0000 .• 0260447 5 72 . COOO .0260920 5 73.0000 . 0161394 574 .oooo . 0261867 5 75. 0000 .026 234 1 576 . a coo ·.026281 4 5 7 7. 0000 .0263288 5 78. 0000 .0263 76 1 579.0000 .U264235 5 8 0 .00 0 0 .026'9708 58 1.0000 . 0265 18 1 582.0000 • 0265655 58) . 0000 . 0266128 584 . 0000 • 021,6602 5 85. 0000 .0267075 586 .0000 .0267549 58 7 . 0000 .0268022 588.0000 .0268496 589 . 0000 . 0268969 590 . 0000 .. 0269442 591 . 0 000 . 0269916 592 . 0000 .0270389 593.0000 .02 70863 594.0000 .0271336 59 5.0000 • 02 71810 596. 0000 .0272283 597. 0000 . 0272757 598 . 0000 . 0213230 599.COOO .07.73704 600. 0000 . 02741 77 601 .0000 . 0274650 602. 0000 . 027 5 124 603 . 0COO . 02 75597 604.0000 . 0276071 605.0000 .0276544 606. 0000 . 0277018 607 . 0000 . 027149 1 608.0000 . 0277965 609 . 0000 • 02784 38 6 10. 000 0 . 0278911 611.0000 . 02 79385 61 2. 0000 . 0279858 613 . 0000 . 0280332 614 . 0000 • U280805 6 15. 0 000 .028 12 79 616.0000 .0281752 6 17. 0000 .0282226 618.COOO .0282699 619.0000 . 0183113 6 2 0 . 0000 .02836'96 62 1. 0000 .0284 1 19 62 2 .0000 .0284593 623 . 0000 . 0285066 624.0000 • 0285540 625. 0000 . 02860 1 3 626. 0000 . 0286487 62 7. oono . 0286960 628 . 0000 . 0287434 629 . oooo • u28 7907 6 30 .. 000 0 . 028 8380 631 .0000 . 029g954 632.0000 .0289327 6 33. 0000 . 028980 1 634 . 0000 . 0190274 b35. 000 0 .0290H8 636. 0000 • 029 1221 63 7. 0000 . 029 1695 638.0000 . 0292168 639. 0000 .0292642 6 40.0000 .02931 15 64 1. 0000 . 0293588 642.0000 .0294062 643.0000 .0294535 644. 0000 . 0295009 6lt5. 0000 . 0295482 646. 0000 . 0295956 647.0000 . 0296429 6'98.0000 . 0296903 649. 0000 • 02971 76 650. 0000 .029 7849 651 . 0000 .()298321 652. 0000 . 0298196 653 . 0000 .02'-192 7 0 654 .oooo . 02911743 655. 0000 . 030021 7 656. 0000 • 03(106'10 65 7 .0000 .030 ll ~4 6'58. 0 000 .0301637 659 . 0000 . 03021 Ll 660. 0000 .0302584 661. 0000 • 03030!)7 662 . 0000 . 0303531 663 . 0000 . 0304004 664 . 0000 . 03044 78 665.0000 • 030495 l 666 . 0000 • 0305425 66 7. 0000 . 0305898 6 6t!.OOOO . 03063 72 669 . oooo .U306845 6 70. 0000 . 0301318 6 71. 0000 .0307792 672 . 0000 .0308265 673.0000 . 0308739 6 74 . 0000 .0109212 675.000 0 .0309686 676. 0000 • 03101'59 677.0000 . 0310633 678.0000 .0311106 679.0000 . 0311580 6 80. 0000 • 0312053 681. 0000 .0312526 682 . 0000 . 0313000 683.00 00 . 031347 3 684.0000 .0313947 685. 0000 • 031 4420 686. 00 00 .0314894 687 . 0000 . 0315367 688. 0 000 .03 15841 689 .oooo .0316314 690. 0000 .0316787 691.0000 .03L7261 692.0000 . 03 17734 656. 0000 . 02,.9300 .02'H653 552. 0000 55 7. cooo .0249171 . 0252123 553.0000 sse.oor.o .0250241 .0252594 554.0000 559 .oooo . 0250712 •0253064 560.0000 . 0253535 561.0000 • 0254005 562. 0000 .02541t76 56 3. 0000 .0254946 564 .oooo .02554 11 565. 0000 5 70.0000 .0255887 • 0258240 566 . 0000 571 . cooo .0256358 .. oz~e-110 567. 0000 572.0000 . 0256828 .0259181 568.0000 573.0000 .0257299 .0259651 56Q.OOOO 574.0000 • 025 7769 • 0260 122 57 5. 0000 • 0260592 576.. 0000 • 0261063 577 . 0000 .0261533 578.00UO .0262004 579.0000 .. 02624 74 5 80.0000 .. 0262945 581. 0000 • 026341 '5 582 .. 0000 .0263tt86 583. 0000 .0264356 58.ft. 0000 .0264827 5 8 5. 0000 • 0265298 586.0000 .0265768 587. 0000 .0266239 588.. 00CO .. 0266709 589.0000 .0267180 590.0000 • 0267650 591.0000 .0?68 1Zl 592. 0000 . 0268591 593. 0000 . 0269062 594 . 0000 .0269532 595 .0000 .0270003 5'16. 0000 .0270473 597. 0000 .. 0270944 598.0000 . 0271414 599. 0000 . 0271885 600.0000 .0272355 601.0000 .. 0272.826 602. 0000 . 0273296 603. 0000 .0273767 604.0000 .0274237 605. 0000 . 02 74 708 606. 0000 . 02751713 607. 0000 .0275649 608.0000 .0276119 609. 0000 • 0276590 610. 0000 • 0277060 611 .. u ooo .0277531 612. 0000 . 0278001 61 3.0000 .0278472 614.0000 .0278942 6 15.0000 .0279413 616.t.iOOO .0279883 617.0000 .0280354 618.00CO . 0280824 619. 0000 . 0281295 620.0000 . 02817bS 621 . 0000 .028223b 622. ccoo . 0282706 62 3.cooo .0283177 624 . 0000 • 028364 7 6 25.000 0 .018 4118 626. OOLU • 0284588 627.0000 .0285059 628.0000 .0285529 629.0000 .0286000 6 30. 0000 . 0286't70 631. cooo • 02869'-1 632.0000 .02814ll 633. cooo . 0287882 63't.OOOO .0288352 635. 0000 640 . 0000 . 0288823 . 02911 75 636.0000 641. 0000 .0789293 . 0291646 637. 0000 64 2 . 0000 .0289764 .0292116 639.COOO 643.0000 .0290234 . 0292587 639.0000 6't't. 000 0 . 0290705 . 0293058 645 .0000 .ozq352e 646.0000 • 02Y3'1l/9 647.0000 .0294469 64A . 0000 .0294940 6't9.0000 . 0295410 6 50. 0000 • 02958ts l 6!it.oooo .0296351 652.0000 . 0296822 653.0000 .0297292 654 . 0000 .0297763 655.0000 .0298233 656. 0000 • 0298704 657.0000 .0299174 65&.COOO . 02996't5 659 . 0000 .030011 5 660 .. 0000 .0300586 661.0000 • U3lll056 662. 0000 .030152 7 663. 0000 .0301997 664 . 0000 • 030246& 665.0000 .0302938 666. OOC\O . 0303409 667. 0000 • 030 )tl79 66B.OOOO . 030't350 669. 0000 • 0304820 6 70. 0000 • 0305291 671 . 0000 • 0305761 6 72. 0000 .0306232 673.0000 . 0306102 674. 0000 . 0307113 675 .. 0000 . 030 7b4j 676. 0000 • u308l 14 677.0000 . U30858't 678.0000 .0309055 619.0000 .0309525 680. 0000 • 0309996 681.0000 . 031046~ 682 . 0000 .0310937 683.0000 . 0311407 684.. 0000 . 0311878 685. 0000 .03123"8 686. cocio .0312819 687. 0COO .0313289 688.0000 . 0313760 689.0000 .03llt230 690. 0000 695.0000 .0314701 . 03 l 7053 691.00UO 696. oouo • tl1 l '> I 71 .0311524 6cn.oooo 697.0000 . 0315642 • 03171.194 69~. 0000 698. 0000 . 0316lll .OH846S 69• .oooo 699. 0000 . 03165B3 . 0318935 700. 0000 105. 0000 710.0000 . 03 19406 .0321759 .0324 111 101. 0000 706. coco 7 11. 0UOO .0319876 .0322229 • 0324582 702. 0000 101. 0000 112.0000 .0320347 .0322700 • 0325052 703.0000 108.0000 713. 00GO . 0320818 . 0321170 .0325523 704. 0000 709.0000 ll't.0000 .032 1288 .0323641 .0325993 71 5.0000 • 0326464 .716.0000 • 0326934 ll7 .0000 . 0327405 718 . 0000 .0327875 719. 0000 • 0328346 720. 0000 725. 0000 730.0000 .03188 16 . 0331 16(# • 033352 1 721. 0000 726. 0000 13 1. 0000 .0329287 • 0331639 .0333992 122.0000 727. 0000 732.0000 .0329757 .0132110 . 0334462 723.0000 728.0000 733. 0000 . 0330228 .0332580 .033493 3 724. 0000 1zq.oooo ?lit. 0000 • 033069'8 . 0333051 • 0335401 735 . 0000 74 0. 0000 745 . 0000 • 03358 74 .0138226 • 03405 79 736.0000 741. 0000 7't6.0000 .0336344 . 0338697 .034 1049 737.0000 742 . 0 000 7't7.0000 .0336815 .033~167 .034 1520 738.0000 7lt3.0000 748. 0000 .0337285 .0339638 . 0341990 739. 0000 744 . oooo 749. 0000 . 0337756 .0340108 .0342't61 75 0 .0000 . 03't293l 751. ocoo • 03434 02 752. 0000 . 03ltl872 753 . 0000 .03't43't3 754 .0000 .03't't813 755.0000 • 0345284 756. 0000 • 034575'­ 757.0000 . 0346225 758.0000 .0346695 759.0000 .03471 66 76 0 .0000 • 0347636 761.0000 .0348107 762.0000 . 03't8577 763. 0000 .0349048 764 . 0000 • 0349519 765 .0000 .0349989 766. 0000 . 0350460 767.0000 .0350930 768.COOO .0351't01 769. 0000 .035 1871 770.0000 .0152342 111.0000 .0352812 772.0000 .0353283 773.0000 . 0353753 774 . 0000 .0354224 775.0000 • 03S't6Y4 776.0000 • 0355165 777 . oooo .0355635 778.0000 .0356106 779.0000 . 0356576 780.0000 .0357047 781 . 0000 .03575 17 782.0000 .0357988 783 . 0000 .0358.C.58 784.0000 • 0358929 785. 0000 • 0359399 786. 0000 . 0359870 787.0000 .0360340 788. 0000 .036081 l 789 . 0000 • 0361281 790.0000 .0361752 791.0000 .0362222 792. 0000 .Q3626V3 793. 0000 • 0363163 794 . 0000 .036363lt 795. 0000 .0364 104 796. 0000 . 036-4575 797. 0000 .03650-45 798. 0000 .0365516 799 . 0000 .0365986 TEM PERATURE 23.20 550.0000 . 0247154 551. CiUOO .0247621 552.0000 . 0248089 553.0000 .024d556 554. 0000 .024902't 555. 0000 • G249"•92 556. 0000 .0249959 5~7 . 0000 .0250427 558.0000 .0250894 559. 0000 .0251362 560. 0000 .U251!:12'J 561 . 0000 • 0252297 562. 0000 . 0252765 563. 0000 .0253232 564. 0000 . 0253700 565.000(1 .07.5416 / 566 . ocoo • 0254635 56 7. 0000 . 0255 102 568.0000 .0255570 569. 0000 • 0256038 ~ 70 . nr1no .•1?':i6 50'i 'i71. 0000 • 0156973 5 72. 0000 .02574.C.O C:,73.0000 .02'>7908 574.0000 .075837'> S 75.0000 • Ol581i4 3 57b. OOOO . 0259310 517.COOO • 0259 77d 5 78. 0000 .0760246 579.000U . u260713 580. UOOll . 0761 ld l 581.t.ivoo . 02616't8 582. 0000 . 0262116 583.0000 . 0262583 584 . 0000 .0263051 585.0000 . 0263519 586. 0000 • 0263986 587.oooo . 0264454 5138.0000 . 026'-921 589. 0000 . 0265389 5qo. oooo • 0265856 '>91.0000 . 0766324 592. 0000 .0266792 593. 0000 . 026725Gl 594 . 0000 . 0267727 5Y5. 0000 600.0000 . 0768194 .0270512 596. 0000 601. OUQO • 0268662 . n211000 597.0000 602 . 0000 .0269 l29 .027146 7 598.0000 601 . 0000 .0269Sq7 .0211·n5 59Gl.OOOO 604 . onoo .0270065 . 0272402 605. 0000 .0272810 606.0000 . 0273337 607.0000 .027 3<105 608 . 0000 . 0274273 609. 0000 .0274740 6 10 . 0000 . 0275208 611 . 0000 . 0775675 612.0000 .0276l't3 6l3.0000 .02166 10 614.0000 . 0271078 6 15 . 0000 620. 0000 • 0271546 . 0279883 f.. 16.UUOO 621.0000 .0278013 • 028035 l 617.0000 622. 0000 .02781.i8l • 0280819 6ld.0000 623. 0000 .0278948 . 07.8l286 619.0000 624. 0000 .021q416 .0281154 625. 0000 .0282221 626.0000 • 028268'1 627.0000 .0281 156 628. 0000 .02tDb2 4 629. 0000 • 0284092 610. 0000 • 0211"559 631.0000 • 028502, 612.0000 . 0285494 633.0000 . 0285962 634. 0000 . 0286429 635.0000 . 021366'H 636.0000 • 028136'­ 637. 0000 .0287832 638.COOO . 0288300 639.0000 .028876 7 640.0000 .0289235 641.0000 • 0289102 642. 0000 .0290 170 64'i.OOOO .0290637 644. 0000 . 0291105 6't5. 0000 .029l5 7 J 646.0000 • 02"12040 6't7 . 0000 .0292508 648.0000 .0292975 649.COOO .0293443 650. 0000 . 02'H'll 0 651.0000 .02943713 652. 0000 .0294846 653.0000 .0295313 654. 0000 .0295781 655. 0000 .02•16248 1,56.00110 . 02967l6 657. 0000 . 02971 83 65A.OOOO .0297651 1159 . 0000 . 02981 l q 660. 0000 • ozq8586 bbl. 0000 .0299054 662 .oooo .029952 1 663.0000 . 0299989 66't. 0000 . 0300"56 665. 0000 .0300924 666. 0000 .0301392 667. 0000 .0301859 668. 0000 .0302327 669.0000 .0302794 670.0000 . 0303262 611. 0000 .03037 29 672.0000 .030'tl97 673.0000 .0304664 674. 0000 . 0305132 675.0000 • 0305600 676.0000 .0306067 677 . 0000 . 0306'535 678.0000 .0307002 679.0000 .0307470 680. 0000 . 0307931 681 . 0000 • 0308405 682.0000 . 0308tH3 681.0000 . 0309340 684.0000 • 0301.1808 685.0000 . 0310275 686.0000 .0310143 687. 0000 .0311210 688.0000 .03116 78 C..89 . 0000 . 0312 146 6CJO . 0000 .031261 3 691. 0000 .031 lOf:H 692. 0000 . 0313S48 693. 0000 .0111to16 694 . 0000 .0314483 695. 0000 . 0314951 696. 0000 .03 1 ~4 1 9 697 . 0000 .0315H86 698. 0000 .0316354 t.99.0000 .0316821 70 0 . 0000 705. 0000 .03l 72t19 • 03 1962 7 101.0000 706. 0000 .0317756 • 0320094 702. 0000 101. 0000 .03 18224 .0320562 703.0000 708. 0000 .0318691 .0321029 70't.OOOO 709. 0000 .0319159 • 03214.97 710. 0000 .0321"'16" 711.0000 . 0322432 112.0000 • 0322900 713. 0000 .0323367 714 . 0000 . 0323835 71 5.0000 .0324302 716. 0000 • 0324770 717.0000 . 0325231 718.0000 .0325705 719.0000 .0326173 120. 0000 725. 0000 • 03266.C.0 .. 0328978 121 .0000 7 26. 0000 . 0327108 .0329.C.46 122 . 0000 121. 0000 . 0327575 .0329':113 723.0000 728. 0000 .Ol28Q't3 .0330381 724 . 0000 729.0000 . 0328510 .0330848 7 30. 0000 .. 0331316 731.0000 . 0331763 1]2.0000 .0332251 733 . 0000 . 0332719 73't. 0000 .0333186 735.0000 .0333654 736. 0000 . 03341 21 737.0000 • 0334589 738.0000 . 0335056 739.0000 . 0335524 740. 0000 . 0335991 741 . 0000 • 0336459 742.0000 .0336927 143.0000 .0337394 744 . 0000 . 0337862 7't5. 0000 .0338329 7't6. 0000 • 0338797 74 7. 0000 • 0339264 748. 00CO . 0339732 749.0000 .OH0200 750. 0000 .0340661 751. 0000 . 0341135 752. 0000 .0341602 753 . 0000 .0342070 754.0000 .0342537 7 55.0000 760. 0000 . 0343005 .034531.i3 756. 0000 761.0000 .0343473 . 03.C.5810 75 7. 0000 762. 0000 .03't3940 • 03't6278 758. 0000 ,,,3. 0000 .031.il.i't08 . 03'467lt6 759.0000 764 . 0000 .03-44875 .0347213 765.0000 • 03.C. 768 1 766. 0000 . 0348148 767.0000 .0348616 768 . 0000 .03'-9083 769. 0000 . 0349551 770. 0000 .03500 18 771.0000 • 0350486 772.00CO .035095't 773. 0000 . 0351421 774 . 0000 . 035188"1 7 75 . 0000 .0352356 776.0000 .u352e2.r. 117. 0000 .0353291 778. 0000 .0353759 779.0000 .035.C.227 780 . 0000 . 035469'­ 76 l . uooo .(.1355162 782.0000 .0355629 783.oono .0356097 784. 0000 • 035656't 785.0000 1qo . oooo 795.0000 .0357032 .0359370 . 0361708 786. 0000 791.0000 1q6 . 0000 • 0357~00 .0359837 . 0 362175 787.0000 792. 0000 797.0000 . 0357967 . 0360305 • 0362643 788. o.ooo 793 . 0000 198. 0000 . 0358435 . 0360773 .0363110 789 . 0000 1·H -. oooo 799.0000 • 0358902 .03612•0 . 0363578 470 Changes in Carbon Dioxide Concentration From Changes in pH TABLE 3-Continued TEMPERATURE 23 . 40 550.0000 • 02454 78 551.0000 .024591tl 552.0000 .0246407 553 . 0000 .0246872 554.0000 .OZ't 1336 555. 0000 .02'47801 556. 0000 .0248266 55 7.0000 . 0248 730 558.0000 .024919"; 559.0000 .0249660 560. 0000 . 02so1i1t 561.0000 • 0250589 562. 0000 .0251053 563.0000 -0251'.H& 5 64 . 000 0 .0251983 565.0000 .0252447 566.0000 .0252912 56 7 . 0000 .0251177 568.0000 .0253841 ,_69.COOO . 025"306 570.0000 . 0254770 sn.oooo .0255235 572.0000 • 0255 700 573.0000 .0256164 574 . 0000 • 0256629 575.0000 .0257094 576 . 0000 .0257558 577.0000 .0258023 578 . 0000 • 02 5648 7 519. 0000 .0258952 580. 0000 . 0259417 581. 0000 • 0259881 582.0000 • 0260 346 583 . 0000 .02608ll 584. 0000 .0261275 585. 0000 .0261740 586 . 0000 ;0262204 58 7 .0000 • 0262669 588 . 0000 .0263 l l4 5A9.0000 .0?6359A 590. 0 000 • 0264063 591.0000 .0264528 592 . 0000 . 0264992 593 . 0000 . 0265457 594.0000 .0265\121 595. 0000 .0266386 596. 0000 .0266851 59 7.0000 .07.67115 598 . 037 620. 0000 • 0278002 621 . 0000 . 027A466 622.0000 . 077893 1 62 1.CCJOO .0279396 624 . 0000 .0279860 625.0000 • 0280325 626. 0000 .0280790 627.COOO . 028l254 628 . 0000 .0281719 629. 0000 .0782183 630. 0000 .0282648 631.0000 . 0283 ll 3 632.0000 .0283577 ">33.0000 .0284042 h34. 0000 . 02d4507 635.0000 • 0284971 636. 0000 . 021:!5436 637.0000 .0285\JOO 638.0000 .02 A6365 639.0000 .0286830 640.. 0000 .02872\14 641.0000 . 0287 75~ 642. 0000 • 02882 24 643 . 0000 . 07.88688 644 . 0000 . 0}89151 645.0000 . 0289617 646. 0000 • 0290082 647.0000 . 0290547 648.0000 .0291011 649. 0000 .02914 76 650. 0000 . 0291941 651 . 0000 • 0292405 652.0000 .0292 8 70 65 3 . 0000 -0293314 1:154 . 0000 . 0293199 655 . 0000 • 0294264 656. 0000 • 0294 728 65 7. COOO .02951Q3 658.0000 .0295658 659. 0001) .0296122 660. 0000 • 02Q658 7 66 l. 0000 . 0297051 662 . 0000 .02"l7Sl6 66':\ . 0000 .02Q7fl81 tl64 .onoo .0298445 665. 0000 .0298910 666. 0000 .0299375 667.0000 .0299839 668 . ccoo . 0)00304 f,6') . 0000 .0300768 6 70. 0000 . 0301233 671 . 0000 .0301698 672.0000 .0)02 162 6 7 3. 0000 .0302617 674.0000 .0303092 6 75. 0000 . 0303556 676.0000 • 030402 1 677 .0000 .0304485 67e.oooo .0304950 67'J.OOOO .0305415 680.0000 . 0305879 681 . 0000 • 0306344 682 . 0000 . 0306809 683.0000 .0307273 684.0000 . 030773A 685 . 0000 • 0308202 686. 0000 .0308667 687 . 0000 • 0301132 68i-•. cooo .0309596 689 . 0000 . 0310061 6QO . 0000 . 0310526 691.0000 . 0310990 692 .oooo .0311455 1>93 . 0000 . 0311Ql9 694 .oooo .0312)84 6Q5. 000 0 .0312849 696. 0000 .93l33l3 69 7. 0000 .0313778 69tt.OOOO .0314243 69Q. 0000 . 0314707 700. 0000 .03151 72 701.0000 . 0315636 702. 0000 . 0316101 703: 0000 .0316566 704 . oooo . 1)31 7030 705.0000 .0317495 706. 0000 .0317960 707. 0000 .0318424 708. 0000 . 0318aA9 709.0000 .031 H53 110.0000 .0319818 111 . 0000 . 0320283 112. 0000 .0320147 713. 0000 . 0321212 714. 0000 . 03211> 11 715.. 0000 .0322 1 4 1 716.0000 .0322606 717.0000 . 0323070 llA.0000 .0323535 719.01)00 .0324000 720.. 0000 • 0324464 72 1. 0000 . 0324929 122.0000 . 0325394 723.0000 .0_325858 724.0001) . 0326321 725.0000 . 0326787 726. 0000 .0327252 727. 0000 .0327717 728.0000 . 032818 l 72q .oooo . 032A646 730. 0000 .0329 1 11 731. 0000 • 03295 75 732.0000 .OHOCJ40 B3.0COO . 0130504 734 . 0000 .Ol3091>Q 735.0000 .0331434 7)6. 0000 • 033 l89d 73 7 . 0000 .0332363 738 . CO OO .0332828 739. cooo . uHH92 71t0.0000 . 0333757 74 1. 0000 .0334222 742 . 0000 .0334686 743.00IJO . 0335151 744 .oooo .IJH56 l 5 745.0000 . 0336080 746 . 0000 .OB6545 747. 0000 .Q33 7UO"l 7't8 . 00tl0 . 0337474 749.COOO . OH7939 750 . 0000 .0338t,03 75 1.0000 .0338868 752 . 0000 .0339332 753.0000 .0139797 754 . 0000 . 0140262 755. 0000 • 0340726 756. 0000 . 0341191 757.0000 .0341656 75 !l. cooo .0142120 759. 0000 • u 34251:15 760.0000 .0343049 76 1. 0000 .0343514 762 . 0000 . 03439 79 71>3 . 0000 .0344't43 764. 0000 .03441108 765. 0000 .0345373 766.0000 .0345837 76 7. 0000 . 0346302 768.00UO .0346766 769 . 0 000 .0\47231 770 .00 00 7 75 . 0 000 .0347696 .03500l9 771 . 0000 7 76.0000 .0348160 • 0350483 772.0000 777 . 0000 .0348625 .0350't48 773.0000 778.0000 .0349090 .Ol514 l l 174.0000 779.00011 . 0}49554 .Ol5lt177 780. 0000 . 0352342 781 . 0000 . 0352807 782. 0000 .0353271 783.0000 .0353736 784. 01)00 . 0354200 785. 0000 . 0354665 786. 0000 .0355130 78 7 .0000 . C355594 7A8. 0000 .0356059 789. 0000 .03')6524 790. 0000 .0356988 791.0000 . 0357453 792. 0000 .035Nl7 793.0000 . 0358382 794 .oooo • U35d64 7 795. 0000 .0359311 796.0000 • 0359776 797 . ooou .0)60241 798.0000 .0360705 799 .oooo . 0)61170 TEMPERATURE 23.60 550. 0000 .02441 l l 55 1. 0000 • 02445 74 552. 0000 .024SU36 553 . 00IJCJ . 0245498 5'54 .0000 • 02459bll 555.0000 • 024642 3 556. 0000 • 0246ts85 557 . 00CO . 0247 347 55A.O OOO .0247810 559.0000 .07. 48272 560. 0000 • 02487 34 561.0000 . 0249196 562. 0000 .0249659' 56 3 . 0000 . 025012 1 5t>4. 0000 .02~0563 565 .00 0 0 . 0251045 566 . 0000 . 0?51508 567. 0000 . 025 l 970 56A. 0000 .0?52432 569.0001) • v75 26'i5 570.0000 . 0253357 571.0000 . 0253819 5"12.0000 . 0254281 573.0000 .0254744 5 7'• · 0001J .0255206 5 75. 0000 580.0000 .0255668 . 0257980 576. 0000 561.0UOO . 02~6130 .0258442 577 . COOO 582.0.0000 .028'1876 650.0000 • 029033tl 651. OOOCJ .0290A01 65l. 0000 . 02'1t2td 65i.000[J . 02q 1725 1is4.r.noo .0292187 655 . 0000 • 02'12tl50 656. 0000 . IJ?.931 12 657.0000 • 029 35 74 65q.cooo .02q1to11 659. 0000 .0294499 660.. 0000 .. 0294961 66 l. 0000 • 0295423 662. coco . 0295886 663.000 0 .02~6348 664 . oooo . 0?96810 665.0000 .02...n212 666. 0000 . U29H35 667 . 0000 .oZ..'3197 66a.oooo .. 0298659 66~. 0000 . 0299122 670 .0000 • 0299 5a4 6 71 . 0000 • 0 300046 6 72 . 0000 .0300508 673.0000 .0300971 674.0000 .0301413 675.0000 • 0301895 676.0000 .0302)57 677.00CO • 0302ts20 678.COOO .03037.82 679.0000 .0101744 680.0000 • 030420 1 681.UOUO • 030466Y b82 . oono .0305131 6fl l. oor.o .0"3055'13 684. 0000 .0306056 68'5i.OOOO .0306518 68t.. ooou • 0306Y8.0 687.0000 .0307442 68A . COOO . 0307905 68Q.0000 • 030A3t.. 7 .b90. 0000 .03088211' 691 . 0000 . 0309291 692. cooo .0309154 693 .. 000') . 03 l02l6 61.14.0000 .03101>78 695.oooo .03l l l't 1 696 . 0000 . 031160) 6f.f1.0000 .0312065 6q~ . oonu .03 12521 699.0000 . o :H2990 700.0000 .0113452 701. 000(..o .0"313914 702. 00<.'0 .0314376 703.001}0 .OH4tl39 704. 0000 .0315301 705 . 0000 110.0000 .0315763 .0318075 706. 0000 711.00llO . 0 316226 .0318531 707 . COOO 112.0000 .03 l 6t..t! B .03lt1'1'19 ros.oooo 71 ' . 0000 . 0117150 .031946 1 70q. 0000 714.0000 . 031 76 12 .031"1924 71 5.0000 . 0320386 711:1. OOOCJ .0320848 71 7 . 001')0 .()321311 718 . 0000 . 0321713 71 9 . 0000 . 03222 35 720 . 0000 .0322697 121 . 0000 .0323lt..O 122. oono . 037.3C..l2 121.0000 . 0324084 724.0000 • Ol24546 725.0000 • 032500'1 726.0000 .0325471 727 . 00UO .0325933 718. 003 1 736 . 0000 • 03 3009't 737.nooo .033f"l ~56 HR . 0000 .0111 0 18 73?.0000 . 0331480 740. 0000 .033 1943 741 . 0000 . 0332405 742 . 0000 . 0332867 743.0000 . 0133330 744. 0000 .. 0333 7'12 745 . 0000 .0334254 746.0UOO .0334716 747.0000 . OB5 1 79 14B . OOOO . 0335641 74" . oooo . 0336103 750 . 0000 • 0336565 751.0000 • 033 1028 752. ooco . 0 3 H490 7<;3.0000 . 0337952 754. 0000 . CJ1l8415 755 . 0000 . 0338877 756.0000 .03}9339 75 7.0000 .OH9 tWl 758.00tiO .0340264 759.0000 .0140726 760. 0000 .0341188 761 . UUOU .034 1650 762 . ouoo . 0342ll3 763. 0000 . 034257~ 764 . 0000 .031t3037 765.0000 .0343499 U,6. ouoo • 0341962 761.0000 . 0344424 768.CCl>O . C344886 769 .oooo .0145349 770 . 0000 .0345811 771 . 0CCC .0346273 777 . COOO .034673'5 113 . OOGO .0347198 774 .oooo .0147660 775. 0000 .034812 2 776. 0000 .0348584 777 . 0000 . 034~047 778.0000 . 0349509 779.0000 .0349971 780 . 0000 .0350434 781 . 00<'0 • 0350896 782.ooou • 035 l 358 f83.000U .0351820 784 . 0000 . 0352283 785 . 0000 .03'>2745 786.00Ct(J .03~3207 787 . 0000 .0353669 788 . 0COO .0354132 789.0000 . 0354594 790. 0000 . 0355056 ·r91 . oouo .0355519 792. OOCJO .0355981 793 . 0000 .035644) 794 .0000 • 0356905 795·.0000 . 035736 8 7~6.00UO .0357830 1~1 . oooo .0358292 798.0000 . 03587'i4 799 . oooo . OJ59217 Changes in Carbon Dioxide Concentration From Changes in pH TABLE 3-Continued TEMPERATURE 23 . 80 550. 0 000 .0242745 551. 0000 • 0243205 552.0000 • 024 3665 553.0000 .02"·H25 554 .-0000 .. 02"'t584 555.0000 • 0245044 556 . 0000 • 0245504 557 . 0000 . 024';'164 558 . 0000 .02't6424 559. 0000 .021t6884 560 .00 00 • 0247344 561 . 0000 • 024 7804 562. 0000 .0248264 563.0000 .OZ't8724 564 .oooo .02't9181t 565. 0000 • 0249644 566.0UOU . 0250103 567 .. 000U • Ol50S63 568.0000 .0251023 569.0000 . 025 1483 S70.0000 .02S1943 571.UUUO • 02~2't03 5 72 . 0000 .0252863 573 . 0000 .0253323 574 . 0000 . 0253783 575 .0000 .0254243 576. 0000 • 0254 703 !i 77 .. ooco .. 0255162 5 78 . COOO .0255622 5 79.0000 .0256082 sao.. oooo • 025654 2 56 1 . CUl)Q • 0257002 582 . coco • 025 7462 5&h0000 .0257922 584.0000 .0258 382 585.0000 .0258842 5d6 . 0000 .0259302 587.0000 .0259762 588.0000 .0260222 589 .0000 .02606 81 590 .0000 . 026ll4l '>91 .. 001)0 .. 0261601 592 .. 0000 .0262061 S93 .. 0000 . 0262521 '>94 .oooo .026 2981 595. 0000 .. l.1263'.41 596 .. 0000 .026390 l 597 .. 0000 .026436 l 598.0000 .0264821 599. 0 000 .026528 l 600.0000 . 02657'.l 60l . OUOO • 0266200 602. 0000 • 0266660 601.0000 .0267 l 20 601t.OOOO .0267580 605.00 00 • 0268040 606 . 0000 • 026'3'>00 607 . 0000 • 0268960 608.0000 . 0269420 609 . 0000 .0269880 6 l 0.0000 .0270340 6ll.OOOO • 02 70800 612.0000 .. 0211259 613.0000 .0271719 61 4.0000 .0212 1 79 6 l 5 . 0000 . 027263'1 616.0000 .0273099 61 7 . 0000 .0273559 6l8.0000 .02740l9 619.0000 . 0274479 620. 00 00 . 0214939 621. 0000 • 02 753<:19 622.(1000 .0275859 623.0000 .0276319 624. 000 0 .0276778 625.0000 .02772]8 t..26. 0000 .. 0277698 627.COOO .0278 158 628. 0000 . 0 278618 629. 0000 ."0279078 6]0 . 0000 . 0279538 63 l .OOOO • 02.,9998 6 32 . 0000 .02804 58 633.0000 . 0 2 80918 634 .0000 . 0281318 635.0000 .0281838 636 . 0000 .0282297 637.0000 . 02827 57 638.0000 . 02832 1 7 6 39. 0 000 . 028 3677 640 .. 0000 . 0284137 641.0000 .. 0284597 642 .. 0000 .0285057 643. 0000 .0285517 6 44.000 0 . 02859 7 7 645.0000 . 02K643 7 646.. 0000 • 0286897 641 . 0000 .0287356 648·. 0000 .02 878 16 649. 0000 . 0 2882 76 650. 0000 . 0288736 651 . 0000 • 02U9 l 96 652 . 0000 .0289656 653. 0 0 00 . 0 29011 6 6 54. 0 000 . 0290576 655.0000 .0291036 656. 0000 . 02?14'16 657.0000 . 0291956 658.0000 . 029241 6 6 59. 000 0 .0292875 660. 0000 .·0293335 661.0000 .029379'> 662.0000 .0294255 663. 0000 . 029411 , 664. 0000 .02951 75 665. 0 000 .. 0295615 666. 0000 .. 0296095 667 .. 0000 .0296555 668 . 0000 .02970 15 669. 0000 • 0 297415 6 70. 0000 6 7'5. 0000 .U2'1/~35 .. 0300234 6 71. 0000 676 .. 0000 . 0298394 • 0300694 672.0000 '677.0000 .0298854 .0301154 6 7 3. 0000 678 . 0000 .0299)14 . 0 301614 674 .. 000 0 679. 0 000 .0299774 .030207't 680. 0000 .. 0302'> )4 681 .. 0000 .. 0302994 682.0000 .0303454 683. 0000 . 030 3913 684 .. 000 0 .. 0304 373 685.. 0000 • 0304tf33 686 . 0000 .0305293 68 l . 0000 .0305753 6 88.0000 .0306213 6 89 . 0000 . 0306673 690.0000 .0307113 691. 0000 .0307591 692.0000 .0308053 6Cit3.0000 .030&513 694. 0000 .0308972 695.. 0000 .. 01oq432 696 . 0000 .0309892 697.0000 .0310352 698.000 0 .0310812 6119.0000 .0311 272 700. ooou .03 11732 101. 0000 . 03121'12 702 .. 0000 . 0312652 703 . o oo·o . 031311 2 704 .coon .0313572 705.0000 .. 0314012 706. 0000 .0114491 101. 0000 .0314951 708.0000 . 0315411 709.COOO . 0115871 110.0000 .03 16 .Hl 111 .. 0000 .. 0116791 n2.oooo .0317251 713. 0000 .0311711 714 . 0000 .0318171 715 .. 0000 .u318ti31 716.UUOO .031"10 732-0000 . 03261t49 733. 0000 .0326909 734 .oooo .0327369 735.0000 • 0127tS29 736. 0(100 .0328289 137. 0000 .0328749 738 . 0000 . 032920 9 739.0000 • 0329669 740. 0000 .0330121./ 741 .. 0000 .. 0))0588 742 . 0000 • 033 1048 743.0000 . 0331508 744. 0000 . 031196tl 745. 0000 .033242tl 746.. 0000 • 0B2t1a8 7"7. 0000 .0333148 74 8 . 0 000 . 0333808 749 . COOO .. 0334268 750.'0000 .0334728 "15 l .. 0000 . 0335188 752 .. 0000 .. 0335648 753. 0 000 .0336107 754 .. 0000 .. 0336567 755.0000 .. 033702 7 756 .. 0000 .. 0337487 757 .. 0000 .0337947 758.00flO .0338407 759.0000 .. 0138867 760. 0000 .0319127 761 .. 0000 . Ol3'Ht17 762.0000 .. 0340247 763 .. 0000 .0340707 764 .. 0000 .0341166 765 .. 0000 .. 0341626 766.0rJDO . 0342006 767 .. 0000 .. 0342546 768 . 00IJO .0343006 769 .. 0000 .. 0143466 770.000 0 .0343926 771 . 0000 • 03443136 111.0000 .0344846 173 .. 0000 .0345306 774 .. 0000 • 0345766 775. 0.000 . 0346226 1n.oooo .. 031t6685 177.0000 . 0347145 778.0000 .0347605 779.000CJ .. 0148065 780.0000 .U348525 781 . 0000 • 0148985 782 .. 00(JO .tJ31t944S 1e1.:o ooo .Ol(i.990'5 784.000U . 03'>036') 785.0000 .03">0825 786 .. oouo .0151285 1B1 .0000 .0151 ·145 788 . 0000 .. 0352204 189.0000 • 0352664 790. 0000 .03Sll24 791 .. 0000 • 0351584 792 . 0000 .03540lt4 793.0000 .0354501t 794.0000 • 0354'i64 7q5., 0000 • 03S5424 796 .. 001)0 • U355884 797 .. 0000 . 0356344 798.COOO .0356804 799.. 0000 .. 0357264 TEMPERA f URE 24 . 00 5 50.0000 . 02410 70 551 . uuco .024152 7 552 . 0000 .. 0241.,84 553.CCOO .. 0242441 554.COOO .0242898 555 .. 0000 .0243355 556 . coco .. u24ldl2 557 .0000 . 0244269 558 . 0000 .. 0244726 559 . 0000 .0245183 '560 .. 0000 . 0245640 561.0000 • G246097 562 .oooo .0246554 563.COOO .0247011 564.0000 • 0241"61:1 565.0000 .0247925 566 .. 0000 .0248381 567 .. 0000 .. 0248838 568 .. 00Q•) .. 07.49295 569 .. 0000 .0249752 570 .. 0000 • 02~07.0~ 571 .. 0000 .. 0250666 572 .. orioo . 0251123 573.00CO .0251580 574 .. 0000 • 02'>203 7 575 .. 0000 .. 0252494 576 .. ()000 . U257.95t 577 .. 00CO .. 025 3408 sn~.OO'.:o .. 0253865 579.0000 .. 0254322 580.. 0000 .02547 7'-I 561 .. U435 5ti9.0000 • 0258892 590. 0000 .0259349 591 .oor.~ .. 02S9H06 592. 0000 .. 0260263 593. 0000 .0260720 594. 0000 .0261177 595 .. 0000 .. 0261634 596 . UOi..;0 .. 0262091 597 .. 0000 .021J254EI 5Q8 . cono .. 0261005 599.0000 . 02634(,2 600. 0000 .0263·H~ 60 1. 00C..J .0264176 602 .. oouo .0264tsB 6u3.001:0 .. 0265290 604 . 0000 .. 0265747 605 . 0000 . 02t.6203 1)06 . C(;OO .. CJ266660 607.0000 . 0267117 601:!.0000 . 07.h1514 609 .. 0000 .. 026!i031 610.0000 .0268408 b 1 1.. OGOO .. 0268945 612 . 0000 .. 0269402 613 .. oorio .0269a59 614.0000 . 0270316 615.0000 • 02707 7 3 6 16. 0000 . 0271230 617 . GOOO . 02716ts7 61A .. OOOO .. 0172144 619 . COOO .0272601 620. 0000 .027305u 1)21.0000 .C..7.13515 622 .. 00'JO .02731172 62 3.000U • 0214429 624 .. 0000 .0274HHb 625.0000 .027S343 f.26. 0000 .. 02 75800 627 . 0000 .0276257 62~.00tJO .. 02 76714 629. cooo .0217171 630. 0000 .0277b2tl 631.0000 .. 027tl085. 632.000U .0218542 633.00!JO • 02 7891./9 634 . 0000 • 07. 79456 635.0000 640. oouo .0279'1113 .. 02d219d 631). 0000 ()4} .0000 .0280370 • 02U2<..5'> 637 .. 0000 6'·2 .. cooo .02b0027 . 0281112 63fl .. 0(JfJO 643.0008 707 . 0000 .. 0312815 708 .. 0000 .0113272 709. 0000 .0311"12 9 110.. 0000 .0314186 711. 0000 .0314643 112.. 0000 .. 0115 100 713 . 0000 . OJ15S57 714 .. 0000 • 0316014 715. 0000 .. 031647 1 716. 0000 .0316928 717.0000 . 0317385 718.0000 .. 0317842 719 .. 0000 .0118299 720 . 0000 .. 03l8755 72 1.. 0000 .. 0319212 122.0000 .. 0319669 723 . 0000 ...017.0126 724 . 0000 .0320583 725.0000 . 037. 1040 726.. 0000 .0321497 72 7.0000 .. 0321954 128.0000 .03 21411 729 . 0000 . 03221168 7 30. 0000 . 0323325 73 1.. 0000 .0321782 732 .. 0(100 .0324239 713.0000 .. 0124696 734 .. 0000 .. 03251S3 735 .. 0000 . 0125610 736 .. 0000 . 0326067 111 .. 0000 .. 0326524 738 .. 0000 .. 0326981 739 .. 0000 .u327438 740.0000 .0327895 741.0000 .0328352 742.0000 .0328809 74 3 .. ooco . 0 329266 744.0000 .0329­123 745.0000 . 0330180 146.. 00CO . 0130637 74 7 .. 0000 .0311()94 748 . CO OO . 033155 1 749 .. 0000 .. 0332008 150. 0000 .. 0312465 751 .. 0000 .. 0332922 752. 0000 .0333379 753 .. 0000 . Olll836 754 .. cooo .. 0334293 755. 0000 .0134750 756. 0000 .. 0335207 757 . 0000 .0335664 758 .. COOO . 0136120 759 .. 0000 .. 0336577 760.0000 .0337034 761.00'JO .0337491 162. 0000 .. 0337948 761 .. 0000 .0138405 764 .. 0000 .. 0338862 765. Ooou .. 0339319 766 .. UlJUO .0339776 76 7 .. 0000 .. 03402)) 76a . oouo .0340690 169 .. cooo .. 0341147 770 .. 0000 .0341604 7 71 .. (1000 .Cr342061 112.0000 .0342518 713 .. 0000 .. 0342975 774.COOO .. 034 34 32 775 .. 0000 .. 0343889 776 .tJOOO .0344346 777.0000 .0144803 178 .. COOO . 03457.60 179 . 0000 • 034571 7 780. 0000 . 0346174 781.UOOO .0346(.,31 78 2 . 0000 • 034 7088 78l.. OOOO .. 034754') 784 .. ooou . 0348002 785 .. 0000 .. 0348i.S9 786 . 0000 .. 1)3483.~_42 1'18. 0000 .0154 39'-1 799 . 000fJ . 0354856 Changes in Carbon Dioxide Concentration From Changes in pH TABLE 3-Continued TEMPERATURE 24.20 sso;oooo ,0239395 55 1.0000 • 02)9849 552 . COOO . 0240303 ss3;oouo .. 0240757 554 . 0000 .U2412ll sss.oooo . 024 1665 556 . 0000 . 0242119 55 7.0000 . 0242573 558 . 0000 .07.43027 55'9 . 0000 .0?4 \49 1 S60.0000 .0243935 561.0000 . 0244 389 562 . 0000 .0244843 563 . 0000 .0245297 564.COOO .024~'1 51 565. 0000 . 0246205 566 . 0000 • 02't6659 561 . 0000 .024 711 3 568 . COOO .0247567 569 . 0000 • 07.48022 5 70. 0000 . 0248476 571 . 0000 . 0248930 5 72 . 0000 • 0249)84 573 . 0000 . 0249838 574 . 0000 . U2502Y2 5 75.0000 . 0250746 5 76 . 0000 .0251200 57 7 .0000 . 025 1654 5 7H. GOOO .07.52108 5 79 . COOO . 02525"62 580 . 000 0 . 02530 16 58 1. UUCO . 025 34 70 582 . 0000 . 025)924 581 . 0COO . 0?543711 Sa4 . 0000 • 02548 32 585.0000 . 0255286 5b6. OU(JU • 025 5 7-'tO 5 87. 0000 . 0256 l 1H 588.COOO . 0 256,., 48 '589.0000 .0:?57l02 590. 0000 . 0257 556 59l. (,UOO .0258010 592. ouoo . 025a464 593.00CO . 0153'118 '>94 .oooo .02593 72 595.0000 .0259826 596. 00(;0 • 0260 280 597. cooo .0260734 59A.CCOO . C26 1 t 89 599 . 0000 . 07.61643 6 0 0. 0000 • 0262097 601. 0000 . 0262551 602 . 0000 .0263005 603.00(,0 .lJ 263459 604 . 0000 .u263.,.13 605. 0 000 .026'936 , 606.0000 • 026482 l 607.0000 . 0265275 608.0000 .0265729 609. 0000 .0266lti3 61 0. 0000 .0266 63 7 6ll. (JCJOO . 0267091 612 . 0000 . 0267545 6 1 3.0COO .0267?'19 6 14 . 0000 • 02684 53 615. 00 00 . 0268907 6 1 6 . 0COO . 026936 l 617.0000 . 02698 15 618. oouo .02 70269 619.000t) . 0270123 620.. 0000 . 027ll 77 621. CliJOO .02 7l631 622 . 0000 .0272085 623.0000 .0212539 "~24 . 0000 .U772'J93 62 5.0000 . 027344 7 626.0C.OO . 0273901 627. 0000 • 027'9355 628 . COOO . 02 1~8 1 0 629 . 0000 . 0175264 630. 00 00 . 02 7571tJ 6 3 1. 0000 .02761 72 632 .oooo . (J7.76626 6 13.0000 .07.77080 634 . 0000 • 077 7534 6)5. ooou 640.0000 . 0277988 .028025CJ 6.36. uooo 64 1. 0(Jno • 02 78441 . 0280712 63 7.0000 642 . 0000 . 0278896 . 028 l l66 638 . 00GO 641. 0 000 . oz 7'1350 .02 13 167.0 639.000u 644 . 0000 .IJ276 14 655.0000 660. 0000 .0287068 .02139339 656.0000 661. o c oo . 0287522 . oz9.,.·7q3 657 . 0000 662. 0000 .02d 7976 .0290247 658.0000 663.CCCO .02ij8 43 1 .0290701 r,sq . oooo 664.0000 .Ol88rl &5 . 02~ 115s 665. 0000 . 02?160~ 666.0(JUO • 02"l'2063 667.0000 . 0292517 6M~. oooo .01·n91 1 669 .0000 . 0293425 670.0000 .0293679 611.0UOU • 0291t333 672 . 0000 .0294 78 7 673.0000 .02~s21.1 674.0000 . 0295695 675 . 0000 . OZ96 l 4 'i 676 . 0000 .0296603 677. 0000 .0297057 6713 . 00CO . 0297511 6 79.0000 . 0297965 680. 0000 • 02984 1"1 681.0000 • 02988 73 682.0000 . 0299327 6 a3. 0000 • 02 '197al 684 . 0000 . u300235 685.0000 . 03UU68'ol 686.0UOU • 1.nu t 1'4 3 61'7. 0000 .030 15'17 688 . 01)00 .0302051 689 0 0000 . 0302'j06 690 . 0000 • 0102960 691. 0000 •. 010l4 14 61i2... 0000 . 0303b68 693.00QO . Ol04l22 694 . cooo .0304776 69s.ooCo . 0305230 6'16.0000 . 0305684 6~7.0000 . OJ0bl3a 698.COOO . 03065qz 6~9.0000 .(130"1046 700. 0000 . 03U7500 70 l. 0000 • 030 N 54 702 . 0000 • 0308't08 703.0000 .0108862 704 ;oooo . oJO<.J316 705 . 0000 • 0309770 706. 0000 .(1310224 10 7 .oooo . 031,06 78 70d.0000 .0311 lJ2 709. 000!) . o JI 1586 110. 0000 .0312040 11 1. 0000 .0112494 112 . 0000 . 03129't8 713. 0000 . 0 313402 714 . 0000 • 0 313856 715. 0000 .03143 10 716 . 0000 .OH476'9 117.0000 . 0315218 71 8. 0000 .Ci1l5673 719 . 11000 . Oll6l27 720.0000 .031658 1 121 . 0000 • 0311035 722. oocu .031'1489 723.0000 .031194~ 724.COOU .Ollt1J97 725. 0000 . 031885 1 726. 0000 • 0319305 727 . COOO . 0319759 728.0000 . C ~ 20H1 729.COO.0COO .0332926 757. 0000 .0333380 758 . 0000 . 03 ne14 759.0000 . 0334288 760 . 0000 . 0314742 76 1. 0000 .0335 196 762 . 0000 . 0335650 763 . 0000 .0316104 764.0000 .u3J6558 765. 0000 .0331012 766. 0000 .033 7466 76 7. 0000 .0337920 7!>8 . 0000 .UJ3ij374 7,,q . 00011 .oHdt\28 770. 0000 . 03l92tJ2 111 . 0000 • 0339736 nz.oooo .0340190 773.00CJO .0340h44 7 74 . coon . u34109tJ 775 . 0000 . 0341552 776. OOIJO . 0342006 111. coco .03"246 1 778.0COO .0342915 779.0000 . Ol4 336fl 780. 0000 .0343823 781 . 0000 • 03442 77 782 . 0000 .03"4131 7133.0000 .0345 185 784.0000 .034563'1 785 . 0000 . 0346093 786 . 00UO' .0346547 787 . 0000 .034 7001 788 . 0000 . 0)47455 789.0000 • Cl34 7909 790.0000 .0348363 791. 0000 • 0348817 1'12 . 0000 .0349271 793 . 0000 . 0149725 794.000() .0350 1 71 795.0000 • 03506 3 3 796. 0000 . 015 1oa1 1'11 . 0000 .035 1541 798 . 0000 . 0351")95 7"19 . 0000 . O i52449 lEMPER ATURE 24 . 40 550.0000 . 0237720 551 . 0000 . 0238171 552 . 0000 . 0238622 553. 0000 .0239073 554.0000 .tl2H >25 555.0000 .023"1976 556. uooo . 02 40427 55 7 .0000 . 024b878 558 . 0000 .0241329 559 . 0000 . 0241HIO 560. 0000 . 0242231 561. ocoo • 02426°H2 562.0COO . 02't3133 563.COCO . 02435a:4 564 . 0000 • 0244036 565.0000 • 024't48 7 566. 0000 .07.4't938 56 7 .0000 . 0245389 568.COCiO . 07.45840 569.0000 .0<"46291 570 . 0000 .0246742 5 71 .0CJOO • 024 7l 93 5 72.0000 . 02476'94 'HJ. CCOO . 02480q5 574 . 0000 .024d546 575 . 0000 .0248998 576.0000 .07.49449 577.0000 . 0249900 '>78 .oooo .025035 1 579.0000 .0250t:I02 580 . 0000 .0251253 581.0000 .025 l 70't 582 . 0000 .0252155 583. couo .C252606 SH't .0000 . 02S305 7 585.0000 .0253508 586. 0000 . C?~3'160 587.oooo . 02544 l l 588 . 00(10 .0254862 5 !:19.0000 • t.)7.55313 590. 0000 . 0255764 591. 0000 .0256215 592 . 0000 .l.1256666 593.0000 .02 571 17 594. OOVO • 025 7560 595 . 0000 • 0258019 596 . 0000 .0258471 591. 0000 . 0258922 598.COCO .0259l73 599. cooo • 025~824 600. 0000 .0260275 601.00CO • 0260726 002 . 0000 . 0261177 603 . 0000 . (126 1678 604 .cooo . U262079 605. 0000 6 10 . 0000 ~:!~~~ 606. ooon 6 11. llOOU .0262"181 . 0265?37 607 . 0000 612 . 0000 .0263433 .. 02656tJ8 608. 0000 613 . 00CO .o2638rt4 .0266119 609 . 0000 t:il4.0000 .0264335 • 0766590 6 15.0000 .026 7041 616.0000 • 026 1492 617.0000 . 0267943 61R . COOO . 026A3<;15 6 19.COOO • 0268tJ46 620. 0000 .0269297 62 1. 0000 .0269748 622.0000 . 0270 l 99 623.0000 . 02 70650 1,24. ooou . 0211101 625 . 0000 . 02 71 552 626 -0000 .0272003 62 7. 0000 .0272454 628.COf!O . 07.7290.., f>29.CJOOO .021335 7 630. 0000 .0273808 631. cooo . 02 74259 632 . coco . 0274 1 lO 633 . 0000 .G775 161 6 34. 0000 . O?"f5612 635 . 0000 .02 76063 6)6. 0000 . 0276 5 14 63 7 .00(1:) . 0276965 638.0000 .0277416 619 . 0000 .0277868 640 . 0000 . 02783l9 641. 0000 .021a1rn &42. 0000 . 0271i22 1 643 . 0UOO .02 79612 644 . 0000 .ui.'00123 645. 0000 • 02d05"" 646 . 0UOO . 0281025 647.0000 . 0281476 64 ~.0000 . 028192 7 64 9 . 0000 . 028237!1. 650. 0000 .0282830 651.0000 . 0283281 652. cooo . 0283732 653 . CCOO .0284183 654. 0000 . 07tJ4634" 655.0000 • 0285085 656. uooo • 02855J6 657.0000 . U285'-18 7 65ij. ooou . 0286438 659. cooo .0286B8~ 660.0000 .02A7340 66 1.0000 . 0287792 bt,? . OO 665.0000 • 0289596 666 . 0000 • 029004 7 t:i6 7. 0000 . 0290498 66:1 . CCtiO . 0290949 669. cooo . 0291400 6 70. 0000 .029 1851 671 . 0000 . 0292303 672.COOO . 07'12154 6 73. 00(10 .0293205 6 74 . OOOtl . 0?.93656 6 75 . 0000 . 02~4107 6 76. ouoo . 0294558 677.0000 .02<;15UO'-i 6 78 . 0000 . 02q5460 6 79 . 0000 • 02959 ll 680 . 0000 . 0296362 681.0000 • 02968 13 6a2. 0000 .029721>5 683.0000 .07.97 716 684. 0000 . 0298167 685 . 0000 .02986l8 686. 0000 • ozq?o69 687.0000 .0299520 68f\.OOOO . 0299971 !>89 . 0000 .0100422 690.0000 . 03008 7 3 69) .0000 .l.1301324 6 'J2. cooo .0301 71 5 69J . OOOO . 0302227 694.0000 . 03026713 695.0000 .030H 29 696 . 0000 • 03035!:10 697 . 0000 .0304(131 69A.C09Q .0304482 699. 0000 . 0104q33 700. 0000 . 0305384 70 1. 0000 • 0305835 702 .oooo . 0306286 703.0000 .0306737 704 . 0000 .030718'1 705 . 0000 • 030 764 0 706. 0000 • 0308091 101.0000 . 0)08542 708.001)0 .0108q93 70q. 0000 . 0309444 110. 00 00 . 0309895 111. 0000 .0310346 7 12 . 0000 .0310 797 713 . 0000 .0311 24A 714 . 0000 • 0311 ·700 715 . 0000 .0312 15 1 716 . 0000 .0312602 7 17.0000 . 0313053 7 18.00IJO . 031 l504· 719 . 0000 .Oll l'-'55 120.00 00 • 0314406 12 1. 0000 . 0314857 122.0000 • 0 315308 121.0000 . 0315759 72't . OOOO .03 16210 725 . 0000 . 0316662 726. 0000 . 0317113 727 .oooo .OH 7564 728. CO~O . 03 18015 729. COOO .0318466 730 . 0000 .0318917 731.0000 .Oll9368 732.0000 . 0319819 733 . 00()0 . 0320270 734.0000 . 0320 f Zl 735 . 0000 .0321172 736. 0000 .032 1624 737.0000 .03220 75 738. 0000 . 0322526 139. 0000 .037.:2971 740.0000 . 032342d 741 . 0000 . 0123879 742.0000 .0321t330 743.0000 . 0324781 744.0000 . 0325232 745 . 0000 .0325683 746 . 0000 . 0326135 747 . 0000 • 0326586 748.00')0 . 0327037 749.• 0000 .0327488 150. 0000 7'i5. 0000 .03z793q .0330194 75 1. 0000 756 . 0000 • 03283qo • 0330645 752 . 0000 75 7 . 0000 • 032884 1 .033 1097 753 . 0000 758.0000 . 0329292 .03H548 754·. ooou 15q . 0000 .032H43 . 0331999 760. 0000 .0332450 761.0000 .033290 1 762 .ocoo .0333352 763. 0000 . 0331803 764.0000 • 03 342 54 765 . 0000 .0334705 766 . 0UOO • 0335156 T~·J.0000 .033560 7 768.0000 .0136059 769.0000 . 03365 10 7 1 0. 0000 .0336961 771. 00C'C.I .03374 12 772 . 00CJO .0337863 773 . 0000 .03 383 14 7 74.0000 . 0338765 775 . 0000 .03392 16 776.0000 .0339667 77 7 . 0000 .0340l 18 771i.OOCO .0340569 779 . 0000 . 0)4102 1 780. 00 00 .034 14 .,2 18 1 .00CO .03"1923 782.0000 . Ol4Z374 793.CCUO .()342825 784 . 0000 . 0343276 785 . 0000 .034372 7 786.0000 .0344178 787 . 0000 .0344!>29 78H . OOOO .0345080 789.00UO .0345532 790.000 0 .03459iS3 791.0000 .03464}4 792.0000 . 0346085 793.0000 .0347336 794.COOO .0347787 795 . 0000 . 03't8238 796.GOOO • 034868? 197 .ooco . 034? 140 798.00CO .0149591 7~9.0000 . 0350042 Changes in Carbon Dioxide Concentration From Changes in pH TABLE 3--Continued TEMPERATURE 24.60 550.0000 • 0236354 551. 0000 .0236803 552. 0000 .0237252 553.0000 .0237701 554.0000 .0238149 555.000U • 0238598 556.0UOO .0239041 557.0000 • 0239'496 558.0000 . 02 39944 559.0000 • 0240393 560.0000 .021t0842 561.0000 . 0241291 562.0000 .0241739 563.0000 .0242188 564 .. 0000 . 0242637 565. 0000 .0243086 566. 0000 . 0243534 567. 0000 .0243983 568.Qf)QQ .0244432 569. 0000 .02448tll 570.0000 .0245329 571.0UOO • 0245178 572.0000 .021t6227 573.0000 .0246675 574 .oooo .0247124 575.0000 .02·"7573 5 76. 0000 • 0248022 57 7.. 0000 .0248470 578 . 0000 .0248919 579.0000 • 0249368 580. 0000 .0249817 58). 0000 • 02S0265 582 .oooo .0250714 583.00CO . 0251163 584 .. 0000 .0251612 585.0000 . 0252060 586. 0000 • 0252509 587.0000 .0252958 588. 0000 .025340 7 589. 0000 • 0253855 S9o.oooo .0254304 591.0000 .0254753 592.0000 .0255202 59·3 .oooo .0255650 594 . 0000 • 0256099 595.0000 .0256548 596. 0000 • 0256996 597.0000 .0257445 598.0000 . 0257894 599. 0000 • 0258343 600.0000 . 0258 Ml 601 .0000 .0259240 602 . 0000 .0259689 603.0000 .0260138 604.0000 • 0260586 605. 0000 .0261035 606. 0000 • 026 l 4H4 607.0000 .0261933 608. 0000 . 0262381 609.0000 .0262830 610.0000 • 02632 79 61l.OOOO .0263728 612.0000 .0264176 613.0000 .0264625 614.0000 ; 026507't 615. 0000 .0265522 616.0000 • 02659 Tl 617.0000 .0266420 618.0000 . C266869 619.0000 .026 7317 620. 0000 .0267766 621. ouoo • 0268215 622.0000 .0268664 623.0000 . 0269112 624 .0000 . 0269561 625.0000 .0210010 626. 0000 .02 70459 627.0000 .0270907 628. 0000 .0271356 629. 0000 .0271805 630. 000(1 .0272254 631. ocoo .0272702 632. 0000 .0273151 633.0000 .02 73600 634.0000 .0174049 635.0000 .0274497 636.0000 • 0274946 637 .0000 .0275395. 638. 0000 . 0275843 639.0000 . 0276292 61t0.0000 .0276741 641.0000 • 0277190 642. 0000 .0277638 643.0000 .02 7808 7 64't.OOOO .0178536 6't5. 0000 .0278985 646. 0000 • 0279433 "647. 0000 . 027~ti82 648.0000 .02"80331 649.0000 .0280780 650. 0000 .0281228 65l. uuoo . 0281677 652. 0000 .02~2126 653.0000 . 0282575 654. 0000 . 0283023 655.0000 .0283472 656. 0000 .0283921 657.0000 .0284370 658.0000 .0284818 659. 0000 • 0285267 660. 0000 .02A5716 661.0000 .0286164 662. 0000 .0286613 66~.0000 .0287062 664.0000 .0287511 665.0000 .0287'159 666. 0000 • 0288,,08 667.0000 • 028865 7 668. 000() .0289306 669.0000 • 0289754 670.0000 • U29lJ203 671 . 0000 • 0290652 672.0000 .0291101 673.0000 .0291549 674.0000 .0291998 6 75. 0000 • 029244 7 6 76. 0000 • 0292896 677.0000 .0293344 678.0000 .0293793 6 79. OGOO .0294242 660. 0000 .02946"10 681.0000 .0295139 682. 0000 .0295588 683.0000 .0296037 684 . 0000 • 0296485 685. 0000 .0296934 686. ocoo .0297383 687.0000 .0297fH2 688.0000 . 0298280 689.0000 .0298729 690.0000 .02~9178 691. 0000 • 0299627 692. 0000 . 0300075 693.0000 .0300524 694. 0000 .0300973 695.0000 . 0301422 696.0000 .0301870 697.0000 . 0302319 698.0000 .0302768 699. 0000 .0303217 700.0000 • 0303665 101. 0000 .0304114 102.0"000 .0304563 703.0000 .030501 l 704. 0000 .0305460 705. 0000 • 0305909 706. 0000 • 0306358 101.0ooo • 0306806 708.0000 .0307255 709.0000 • 030 7704 110.0000 .0308153 711. 0000 .0308601 712 .0000 • 0309050 713.0000 . 0309499 714.0000 • 0309948 715.0000 .0310396 716.0000 .0310&45 717.0000 .0311294 718.0000 .0311743 719.0000 .0312191 720.0000 .0312640 121.0000 .0313089 722.0000 .031 3537 723.0000 .0313986 724. 0000 .0314435 725. 0000 .0314884 726.0000 .0315332 72 7. 0000 . 0315781 728.0000 .0316230 729. 0000 .0316679 730. 0000 .0317127 731.0000 .03175 76 T32. 0000 .0318025 733.0000 . 0 318474 734. 0000 . 0318922 735.0000 .0319371 736. 0000 .0)19820 737.0000 • 0320269 73ti. 00\JO .03207l7 139.0000 .0321166 71tO.OOOO .0321615 1... 1.0000 • 0322064 742. 0000 .0322512 743. ()000 .0322961 744. 0000 .0323410 71t5.0000 .0323858 746.0000 • 0324307 747.0000 . 0324756 7't 8 .COOO .0325205 7't9.0000 • 0315653 750. 0000 . 0326102 751.0000 .0326551 752. 0000 .0327000 753. 00CO .0327448 754 .cooo . 032 78"17 1ss.oooo .0328346 756.0000 .0328795 757.0000 .0329243 75 8.00(.;0 . 0329692 759.0000 .0330141 760. 0000 • 0330590 761. 0000 . 0331038 762 .oooo .0331487 763.00CO .0331936 764.0000 .0332385 765. 0000 .0332833 766.0000 .0333282 767.0000 .0333731 76~.oooo .03341 79 769 .oooo .0334628 110.0000 .0335077 771.0000 • 0335526 772.0000 . 0335'l74 773 . 0000 .0336423 774 . 0000 .0336872 775.0000 .0337321 776. 0000 • 0337769 777.0000 .0338218 778 .00()0 . 0338667 779.0000 • 03391 16 780.0000 • 0339564 781.0000 .0340013 78?. OOGO .0340462 783.00()0 .034091 l 784. 0000 .0341359 785. 0000 .0341808 786.0000 .0342257 181. 0000 . 0342/05 78B.OOOO .0343154 789.0000 . 0343603 790.0000 • 0344052 791.0000 • 0344500 792.0000 • 0344949 793. 0000 .03,,5391! 794. 0000 .0345847 795. 0000 .0346295 796. 0000 . Q3't6744 797. 0000 . 0347193 790.0000 .0347642 799. 0000 • 0348090 TEMPERATURE 24. 80 550. 0000 • 0234989 551.0000 .0235436 552 . 0000 .0235ti82 553.0000 .0236328 55't .oooo .0236775 555.0000 .0237221 556.0000 .0~37668 557. 00{)0 .0238114 558.0000 . 0238560 ';59.0000 .02 3'1007 560.0000 . 0239453 561.0000 .0239899 562 . 0000 .0240346 563.0000 .0240792 564. 0000 .0241239 565.0000 .0241685 566. ocoo .0242131 567.COOO .0242578 568.0000 . 0243024 569. 0000 • 02434 71 570.0000 .0243917 571 . 0000 . 0244363 572.0000 .0244810 573. 0tlOO • 0245256 574.0000 • 0245702 575.0000 . 024614'J 576.0000 • 0246595 577.0000 .0247042 578.0000 .0247488 579.0000 .0247934 580.0000 .0248381 581.0000 .0248827 582.0000 .02492 74 583.0000 .0249720 58't.OOOO .0250166 585. 0000 .025061 3 586. 0000 .0251059 587 . 0000 • 0251505 588.0000 . 0251952 589.0000 .02523"18 590.0000 • 0252B4 5 591. 0000 . 0253291 592. ooou .0253137 593.0000 .0254184 594. 0000 .0254630 595.0000 . 02550 77 596.0000 .0255523 597. 0000 .0255969 598.0000 .0256416 599.0000 . 0256862 600.0000 .025730d 601.0000 .0257755 602 .0000 . 0258201 603 .0000 . 0258648 604. 0000 . u25<.J094 605.0000 .0259540 606. 0000 • 025998 7 607.0000 .0260433 608.0000 . 0260880 609.0000 .Oi61326 610.0000 . 0261772 611.0000 .0262219 612.0000 .0262665 613.0000 .0263111 614.0000 .0263558 615.0000 • 0264004 616. 0000 .0264't51 617.0000 .0264897 618.0000 .02 65343 619.0000 .0265790 620.0000 .0266236 62 l.0000 • 0266682 622. 0000 .0267129 623.0000 .0267575 624 . 0000 • 0268022 625.0000 • 0268468 626. 0000 • 0268914 627 . 0000 .0269361 628.0000 . 0269807 629. 0000 . 027025'4 630. 0000 • oz 10700 631.0000 .027ll46 632. 0000 .0271593 633. 0000 • 02 72039 634.0000 .02 72485 635. 0000 .11272932 636. ocoo • 02 73 3 78 63 7. 0000 .0273825 638.0000 .02742 7l 639.0000 .0274717 b40.0000 .0275164 641.0000 .0275610 642. 0000 .0276057 643.0000 . 0276503 6't4. 0000 .0276949· 645. 0000 .0277396 646. 0000 .0277&42 647. 0000 .. 0278288 648.0000 .0278735 649.0000 .0279181 650. 0000 . 0219628 6!> 1. 0000 • 0280074 652. 0000 • 0280520 653.0000 .0280967 654.0000 .0281413 655.0000 .V281860 656.0000 • 0282306 657.0000 .0282752 658.0000 .0283199 659.0000 .0283645· 660.0000 • 028409 l 661.00()0 • 0284538 662. 0000 .02e4984 663.0000 .0285431 664.0000 .0285877 665. 0000 .0286323 t.66 . 0000 .0286770 667.0000 .0287216 668.0000 .0287663 669.0000 .0288109 670.0000 .0288555 671.0UOO • 0289002 672.0000 • 0289448 673.0000 .0289894 674.0000 . 0290341 675.0000 .0290787 676.0000 .0291234 677.0000 .0291680 678.0000 .0292126 679.0000 .0292573 680.0000 .0293019 681. 0000 • 0293466 682. 0000 .0293912 683 . 0000 .07.94358 68't.OOOO • 0294805 685. 0000 • 0295251 686.0000 .029569 7 687. 0000 .0296144 688. 0000 .0296590 689.0000 .0297037 690.0000 695.0000 .02974B3 • 029?71 s 6')1. 0000 696. ooco • 0297929 . 0300161 692. 0000 697. 0000 . 0298376 • 0300608 693.0000 69Fs.OOOO .0298822 .0301054 694.0000 699. 0000 .02?9269 • 0301500­ 700.0000 .0301947 101.0000 .0302393 702 .oooo .0302840 703.0000 .0303286 704 .0000 .0303732 705.0000 .0304179 706.0000 • 0304625 707. 0000 .0305071 708.0000 . 03055 18 1oq .oooo .0305964 110.0000 715.0ooo .030641 l • 030864 3 111.00110 716. 0000 .0306857 • 030908') 7l2.0000 717.0000 . 0307303 .. 0309535 71 3 .oooo 718.COCO .0)07750 . 0109'1R2 714.0000 71q.oooo .0308196 .0310428 120.0000 .0310874 721. 01JO() .0311311 122. ouoo .0311767 723.oono .03122 14 724. 0000 • 0 ll 2660· 725.0000 .0313106 726.00f,O . 0313553 727.0000 .0313999 728.00CO . 0314446 729.0000 . 0314892 730. 0000 .0315338 731 .0000 .0315785 732.0000 .0316231 733.0000 .0316677 714.0000 .Oll712't 735.0000 .0311570 736.0000 .0318017 737 . 0000 .0318463 738.0000 ·.0118909 739.0000 .0319356· 740.0000 .031 '11802 741.0000 • 0320249 742.0000 . 0320695 743 .0000 . 0321141 744.00()(1 .0321588 7't5. 0000 • 0322034 746. ccoo .0322480 74 7. 0000 .0322927 748.0000 . 0123373 7~9.. c.ooo .0:'\2ltJ20• 750. 0000 .0324266 751.0(100 . 032.4712 152.oooa . 0325159 753.0000 . 0325605 754.0000 .0326052 755.0000 • 0326498 756. 0000 • 0326944 757.0000 .0327391 758.0000 . O"l27U37 759. 0000 .032828). 760. 0000 .0328730 761.0000 .0329176 762.0000 .0329623 763 .00CO .03 30069 764.0000 .0330515­ 765.000Q .0330962 766. 0000 .0331408 767.0000 .0}31855 768. 0000 .0132301 769.0000 .0332747 770.0000 .0333 194 771.0000 .0333640 772.0000 .0334086 713.0000 .U33'-533 174 .oooo .OH't979' 775.0000 .0335426 776.0000 • 03358 72 111.0000 .0336318 178.COCO .03 36 765 779. cooo .0337211 780. 0000 785.0000 790. 0000 .033"/657 • 0339889 . 0342121 781.0000 1ti6. 0000 791. 0000 .0338104 .0340336 • 0342568 782 .oooo 787. 0000 "192. 0000 .0338550 .03't0782 .034301'­ 783.0000 788. 0000 793. car.a .033899 7 . 0341229 .0343460 784.000(> 769.000(J 714.0000 • 0339443 . 0141675 .0343907 195.0000 .0344353 796.. 0 000 .0344'100 797. 0000 .034'>246 798.0000 .0345692 7'19 . 0000 .0346139 474 Changes in Carbon Dioxide Concentration From Changes in pH TABLE 3-Continued TE"PERATURE 25.00 550.0000 .0233625 551.0000 .. 0234069 552. 0000 .0234S13 553.00UO .0234957 554.0000 • 0235401 555. 0000 .0235845 556. 0000 .0236289 55 7. 0000 .0236133 ssa.ooc;o .UlHl 17 559.0000 .0?:3 7621 . 560.0000 565. 0000 570.0000 .02380,65 .. 0240285 .0242505 561.0000 566. 0000 571.0000 .. 0238509 .0240729 .0242(H9 562.0000 567. 0000 572.0000 .OZ389S3 .0241173 .0243393 'i63.0000 56R .OOCO 573.0000 .oz 3q397 .0241617 .07.43837 564.0000 s6q.oooo 574.0000 .02398t,l . 071t206l .0244281 575.0000 .0244 725 576.0000 • 0245169 577.0000 .024561} 578.0000 . 024605 7 519.0000 .0246501 seo.oooo .0246945 581. 0000 .. 0247389 582. 0000 .0247833 583.0000 .0248277 584. 0000 .0248772 585. 0000 .02it9l6b 586. 0000 .021t9610 587.0000 .0250051t 588. coco .0250it98 589.0000 • U250942 590.0000 • 0251386 591.0000 . 0251830 592. 0000 . 02522H 593. 0000 .0152718 '594. 0000 .0253162 595.0000 .0253606 596. 0000 • 0254050 59 7.0000 .0251tit94 598.00CJO .0254938 599. 0000 • 07.55382 600.. 0000 . 0255826 601. 0000 .0256270 602.oooo .0256114 603. 0000 . 0257158 604.0000 .0257602 605. 0000 • C258046 606.COCO • 0258490 607.0000 . 0258"131t 608.CCCO .0259378 609.0000 • 0259822 610.0000 • 0260266 611. uooo .0260710 612.0000 .026115' 613.0000 .0261598 6llt.OOOO • 026204t2 6l5.0000 .0262486 616. 0000 .0262'130 617.0000 • 026.3374 618.COCO .0263818 619.0000 .0264263 620. 0000 . 0264707 621. coco • 0265151 622.0000 .0265595 623. 0000 . 0166039 624.0000 .0266481 625.0000 • 026692 7 626. 0000 • 02673 71 627. 0000 .0267815 628.0000 .0268259 629.0000 .0268703 610.0000 .0269147 631.0000 .0269591 b32. 0000 .0270035 633.CCOC .027Clt79 631t. 0000 .0270923 6.Vi•. 0000 .0271361 636. 0000 .0271811 637.0000 .0272255 638.0000 .07.72699 639.0000 .027lllt3 '61t0.0000 645. 0000 650. 0000 655.0000 660. 0000 665.. 0000 610. 0000 6 75. 0000 680. 0000 685. 0000 690. 0000 695.0000 700. 0000 .0273587 .0275807 • 0278027 .0280248 .0282468 .0284688 • 028b908 .029q129 .0291348 .0291568 .0295789 • 0298009 .0300229 641 . 0000 646. 0000 651 .0000 656. 0000 661. 0000 666. 0000 671 .0000 6 76. 0000 681 . 0000 686. 0000 691 . 0000 696. 0000 701.0000 .0271t031 .0276251 .0278471 • 0280692 • 02ti29 l 2 .0285132 .0287352 .0289572 .0291792 .0294012 .0296213 .0298453 .030067J 642. 0000 647. 0000 652.0000 657.0000 662. 0000 667. 0000 6 72 .oooo 617. 0000 682. 0000 687.0000 692. 0000 697.oooo 702 .oooo .027itit75 .,0276695 ..0278915 .02811)6 -0283356 .0285576 .0287796 .0290016 .0292236 .0294456 .0296677 .0298897 .0301111 6~1; 0·000 648. 0000 653.0000 65~. 0000 663.0000 668.0000 673.0000 618.0000 683.0000 688.0000 693.0000 698.0000 703.0000 .0271t919 .0277139 .027'H60 .0281580 .0281800 .02 86020 .0288240 .0290460 .0292680 .0294901 .0297121 . 029'B4t .0301561 6.ft4.0000 61t9.0000 651t .oooo 6'5q .oooo 664.0000 669.0000 6 74. 0000 67q.oooo 684.0000 689.0000 694 .oooo fli9q.oooo 701t.OOOO .0215163 .027758) .0279804 • 0282024 .0284244 .0286464 • 0288684 .0290901t .0293124 .0295345 • 0297565 .0299781) • 0302005 705. 0000 • 0302itit9 706. 0000 • 03028Q3 707.0000 .OfoHH 708.0000 . 0303781 709. 0000 .0304225 no.oooo .0304669 111.0000 . 0305113 712.0000 .0305557 111.0000 .0306001 714.0000 . 03061t45 715. 0000 .0306889 716. 0000 .0307333 111.. 0000 .0307777 718.0000 . 0308221 7l9.00UO • 0308665 120.0000 .0309109 721.0000 .0309553 122.0000 .0309Cil98 721.0UOO . 0310442 724 .oooo .0310886 725.0000 .0311330 726. 0000 .0311774 727.0000 .0312218 728.COOO .OH2662 72<1. 0000 .0313106 730.0000 .0313550 731.0000 .0313994 732.0000 .03litit38 H3.0000 .0314882 734.0000 .0315326 735.0000 .0315770 736.00UO .0316214 137.0000 .0316658 73A.OOOO .0317102 739.0000 . 0317546 740.0000 .0317990 741. 0000 . 03lt1431t 742-0000 .0318878 1't3. 0000 .0319322 7't4.COOO .0319766 71t5.0000 . 0320210 746. 0000 • 0320654 747.0000 .0321098 748. 0000 .0321542 749. 0000 .0321986 750.0000 . 0322430 751.0000 • 03228 74 752. 0000 .0323318 753.0000 .0323762 754 .. 0000 .0324206 755.0000 .0324650 756. 0000 • 0325094 757.0000 .032553q 758.0000 .0125983 759. 0000 • 032642 7 760.0000 • 0326871 761.0000 . 0327315 762. 0000 .0327159 761.0000 .0328203 764. 0000 .. 0328647 765. 0000 • QJ2909 l 766.0000 .0329535 767 .oooo .032~979 768. 0000 .. 0310423 769.0000 .0330867 770.0000 . uJHHl 771.0000 .OH1755 777-.0000 .0332 l 99 773.0000 .03 3264l 71't.OOOO .OH3087 775.0000 .Ol135H 776. 0000 . 0333975 777.0000 .03341tl9 778.0000 .0134863 779. 0000 . 0315307 780. 0000 .03357)1 781.0000 .0336195 782 .. 0000 .0336639 783.0000 . 03·17083 784.0000 • 0337527 785.. 0000 .03371171 786. 0000 .0338415 787.0000 .0338859 788.0000 .0139303 789.0000 • 033974 7 790.000(1 .U34019l 791 . 0000 . 0340636 792.0000 . 03"1080 793.0000 .0341524 794. 0000 .0141968 795.0000 .0342412 796. 0000 .03't2856 797. 0000 .0343300 798.0000 .0143744 799.0000 .0344188 TEMPERATURE 25.20 550. 0000 .0232260 5'51.0000 .0232702 552.0000 .023'3143 553.0000 .0233585 554 . 0000 .0231t027 555.0000 • 02 l446H 556. 0000 • 0234910 557. 0000 .0135352 558.0000 .0235793 559.0000 .0236215 560. 0000 .0236677 561.0UOO .0231118 562.0000 .0237560 563.0000 .0238002 564.0IJOO .0238443 565.0000 .0238885 566. 0000 .0239327 567.0000 .0219768 568.0000 .02407-10 569 .oooo • 0240652 570.0000 .0241093 571.0000 .0241535 57?. 0000 .0241977 573.0000 . 0242itl 8 5 14 .cooo .02it2860 575.0000 .02it3302 576. 0000 .02it371tl 517.0000 .0244185 s1a . oooo .024462 7 51Cil.OOOO . OZ1t5068 580.0000 .0245510 581.0000 .0245952 582. 0000 .0246393 583.0000 .0246835 584.0000 • 024 7277 585. 0000 .0247718 586. 0000 .0248160 567.0000 .0248602 588. 0000 .0249043 5rl9.COOO .02it9485 590.0000 .0249927 591. 0(100 • 0250369 5•n:.oooo .0250810 5?3.0000 .0251252 '594.0000 .0251694 595.0000 . 0252135 596. 0000 • 02525 77 591. 0000 .02530lq 598.0000 • 0253460 599.0000 .. 0253902 600.0000 • 0254344 601.0000 .0254785 602. 0000 . 0255227 603.0000 . 0255669 601t. ooou .02'56 110 605. 0000 .0256552 606. 0000 • 01:56~94 607.0000561 681. 0000 .0291003 684 . 0000 .0291444 685.0000 • 029 18116 686. 0000 . 0292 )28 68 7. 0000 • 0292 169 68a . 0000 .0293211 h89. 0000 .0293653 690.0000 • 0294094 691. 0000 . 0294536 692. 0000 . 0294978 693 . 0000 .. ozq5ft\9 694. 0000 .0295861 695.0000 -0296303 696.0000 • 0796744 697. 0000 .029 7186 698. 0000 .0297628 699. 0000 .0298069 100 .. 0000 .0298511 701. 0000 . 0298953 702.0000 .0299394 703. 0000 • 029q836 704. 0000 • 03002 7.tl 705.0000 .0300719 706.0000 . 0301161 707 . 0000 .030 1603 708.0000 . 010201,4 709. coou . 1no21tttb no.oooo . 0302928 711.0000 . 0303369 712.0000 .0103dll 71.3.0000 .0304251 714. 0000 • Ol04b91t 715.0000 .0305136 716.0000 .0305518 717.0000 .0306020 71 8 .0000 • 030646 I 719. 0000 • Ul0690l 120.0000 .0307345 121 .. 0000 .U30H86 722 . 0000 .0308£28 723 . OO•IO .0308670 "124.0000 .01091 11 725. 0000 • 0309553 726. 0001.) .0309995 727.0000 .O HOit36 128.00110 .OH0878 729.COOIJ .Ull\320 730.0000 .,Ol l 1761 731.0000 .0312203 732. cooo . 0312.645 733 . 0000 .0111086 734. OOOG .031J528 735.0000 .0113970 736. 0000 .0314411 73 7. 0000 . 0314853 738.0000 .Ol 152'15 139.0000 . 0115136 740.0000 .0316178 7itl. OOOO • 0316620 742. OOCJO .0317061 74 3. OOCJO .0317503 744.0000 .0317945 71t5.0000 .0318386 746.0000 .03188 28 747.0000 .0319270 74 8 . 0000 . 0319111 749. 0000 . 0320153 750.0000 . 0320595 751.0000 • 0321036 752. 0000 .0321478 753.0000 .0321920 754. ouoo .ul2?361 755.0000 .0322t1U3 7'56. 0000 . 0323245 757 .oooo . 0323686 759.0GUO .0324128 759. COUO . u324570 760. 0000 • 03250 l z 761.0000 . 0325453 762. cooo .0125895 763.0000 .0326337 764. 0000 . 0326778 765. 0000 . 0327220 766.0000 .0327662 167.0000 . 0328101 768 . COOO . 0128545 769. cooo .0328987 770.0000 . 0329428 111.uooo • 03298 70 772. 0000 .0330312 773.00UO .0330753 774 .oonu .0331195 775.0000 .031163 7 776 . 0000 • 0332078 777.0000 .0332520 118.cor.o . 0312'162 779. 0000 .0331403 780. 0000 • 0333845 78 1.0000 .0314287 782. 0000 .0334728 783.0000 .Ol l5170 784.0000 . 03l5"b l 2 785.0000 .03 36053 786 .0000 .0336495 787.0000 .0136931 788.CO()O .03H378 789.0onu .013 787.0 790.0000 .u338262 791.0000 .0338103 792.0000 .033q145 793.0()C:O . 0119587 7'14.0000 • 034002a 795. 0000 . 0340470 796.·oooo .0340912 797. 0000 .03itl 353 798 . COOO . 0 1411'15 799 . o o:}(l .0142?17 Changes in Carbon Dioxide Concentration From Changes in pH TABLE 3-Continued TEMPERATURE 25.ltO 550.0000 555.0000 .0230 587 .0232781 551. 0000 556.0000 .0231026 .0233220 552.0000 557.0000 .02)1465 .0233659 553.0000 558 . 0000 .0231904 . 02llt097 55't . OOOO 559.0000 . 0232342 .0 234536 560.0000 .02)4t975 561. 0000 • 0235't13 562 . 0000 .0235d52 561.0000 .0236291 56't. 0000 .07.36130 565.000U .0237168 566. 0000 • 0237601 56 7. 0 000 . 023801t6 568.0000 .0238485 569 . 0000 . 0238923 570.0000 .0239362 571.0000 . 0239801 572. 0000 .0240240 573 . 0000 . 0240678 574.0000 .0241117 575.0000 580.0000 .021tl556 • 021t3749 576.0000 se1.oooo . 0241995 .0244188 577.0000 582 .oooo . 021t2433 .02't4627 578 . 0000 583.0000 .0242872 .0245066 5M. 0000 584. 0000 .. 024Hll . 0245504 585.0000 .0245943 586. 0000 • 0?.46382 587. 0000 .02't6821 588.0000 .0241259 589. 0000 • 02 4 7698 590.0000 .0248137 591 . 0000 . 0248576 592.0000 .0249014 593.0000 .0249453 594. 0000 • 0?.49892 595.0000 • 0250330 596. 0000 .. 025076'1 597.0000 . 0251208 598 .. 0000 .025164 7 599.COOO .025208~ 600.. 0000 • 0252524 60l.OOOO .02S296l 602 .oooo . 0253402 603. 0000 .0253840 604. 0000 .0254279 605.0000 .0251t718 606. 0000 .0255157 607 .. 0000 . 0255595 608. 0000 . 0256034 609. 0000 .02~6473 610.0000 .0256912 611. 0000 .0257350 612 .0000 • 025 7789 613.0000 .0258228 614.0000 • 0258666 615.0000 .0259105 616. 0000 .0259544 617.0000 .. 0259983 618.0000 . 0260421 619.0000 • 0260860 620.0000 .0261299 621.0COC . 026 1738 622. ocoo .02621 76 623 . 0000 . 0262615 624. 0000 .0263054 625.0000 .0263493 626 . 0000 • 026 3931 627.0000 .0264370 628~0000 . 0264809 629 . 0000 .0265247 630.0000 635.0000 • 0265686 . 0267880 63 1 .0000 636. 0000 .0266125 .0268319 632. 0000 637. 0000 • 0266564 .0268~57 633 . 0000 638.COOO .0267002 . 0269196 634,0000 639.0000 .026 7441 .07.69635 6-40.0000 . 0270074 641.0000 .0270512 642. 0000 .02 10'J\5 1 643.0000 .0211390 644.0000 .0 2 71829 6-\5.0000 .0272267 646 . ocoo .027 2 706 647.0000 . 027)145 648.0000 .0273583 649.0000 . 0274022 650.0000 .0274461 65 1.0000 .0274-100 652. 0000 .0275338 653 .. 0000 .0275777 654.0000 . 0216216 655.0000 . 0276655 656.. 0000 .. 0271093 657.COOO .0217532 658.COOO .0217911 659.0000 . 0278410 660.0000 • 0218848 661 . 0000 .0279287 662. 0000 .0279126 663.0000 . 028016lr 664. 0000 . 0280603 665.0000 .0281042 666. 0000 . 0281481 667. 0000 .0281919 668.0000 .0282358 669.0000 .02 821rn 670. 0000 .0283236 671.0000 . 028367't 672 . 0000 .028"1 ll 673.0000 .028'4552 6 74. 0000 • 0284991 675.0000 .02851t2i 676.0000 -0285868 6 77. 0000 .0286307 6 78. 0000 .0286746 679.0000 .0287184 680.0000 .0287623 681.0000 • 0288062 682 . 0000 • 0288500 683.0000 . 0288939 684. 0000 . 0289378 615.. 0000 .0289817 686.0000 . 0290255 b81 .. 0000 • 0290691t 688. 0000 . 0291131 689. 0000 . 0291572 690.0000 695.0000 .02920 10 • 029,.204 691 . 0UCO 696. ouoo • 0292449 .!lZ.94">"3 6cn.oooo 66 718.0000 . 010429~ 719.0000 . 0304 134 120.0000 725.0000 .. l.i305 172 • 0307 366 121.0000 726. ooou • u'\056ll .0307805 77.2.0000 727.0000 • 0306050 .0308244 723.0000 728.000U .0306'489 .0108682 7 24. 0000 729.0000 . t.H0692 ' .0309 121 7)0.. 0000 735.0000 740. 0000 • 0109560 .0311753 .0113941 731.0000 736.0000 741. 0000 • 0309998 • 0312192: .0314186 112 .0000 7) 1. 0000 742.0000 .0310'437 . 0'112631 .0314625 7).J. 0000 rie.oooo 74 3 . 0000 .0310876 . 031)070 .. 0315263 734.0000 739 . 0000 744.0000 .Olllll5 .U3l3508 .0315702 745.0000 . 0316141 746.0000 .03165 19 14 7. 0000 . 03170 18 748. 0000 . 0317457 749 .. 0000 .0317896 750.. 0000 . 0118 :n4 751.00IJO . Oll871l 752.0000 . Ull9Zl2 753.0000 . 0119651 754. 0000 . 0120089 755.0000 .. 03205lH 756.0UOO • 032096 1 15 7.0000 .031l't06 758.. 0000 .0321H44 759.0000 .037.22A l 760.0000 .0322 122 761 . 0000 .0323161 761.0000 .0323599 763.0000 .0324038 76'4 . 0000 • 0321t4 77 765. 0000 . 03249 15 766. 0000 .03253~4 767.0000 .0325793 768.00IJO .0326232 769 . oooo • 03266 70 770.. 0000 .. 032710~ 771. ouoo .Ol2 1548 77 2 . 0000 .0327~87 773.0000 . 0328425 774.0000 .U328864 775.. 0000 .. 0329303 776. 0000 .0329142 777.0000 .03]0180 778.0000 . 0130619 7 79 .. 0000 .0131058 780.0000 .033149b 781 . 0000 . 0331935 782.COOO .03323 74 783.COOO .0332813 784.0000 .OH12'H 785.0000 .033lb90 786. 0000 . OH4 1 29 181.0000 .0134568 788.0000 .0315006 789 .. 0000 .0135-445 790.. 0000 .. 0335884 791. 0000 . u336323 1 ~2. 0000 . 0136161 793.0000 .0337200 794. 0000 .0337639 795.0000 . 03380 18 796. 0000 .0})8516 191. 0000 .0139qs5 798.0000 .0339394 799. 0000 • 0339832 fEHPERATUA.E 25.60 550.0000 .0229222 551.0UC..0 .0229650 '>J2.00CO .0230095 553.0000 .0230531 554 . 0000 • 0230968 555. 0000 .. 023 l 404 556. 0000 . 02 31841 55f . OCOO .023227 1 558.COOO . 0232713 559 . 0000 .02lll50 560. 0000 . 0233586 5bl.OU00 .U23407.2 56?. 0000 .0234-459 '>63.0000 . 013489S 564 .oooo . 0235132 565.0000 .02357t>S 566 . 0000 .0234204 ';(, 1.0000 .02166'4 1 568.0000 . 0237077 569. 0000 .0237513 570.. 0000 .. 02 37950 5 71.0000 . 01183ij6 5 72.00 00 . 0238823 573 .. 0000 .0239259 5 71t . OOOO . 0239695 575.. oooo • 01'tO l 32 5 76. 0000 • 024056ft :>77.0000 .0241U05 578.0000 -0241441 579.0000 . 02-4 18"17 580.0000 .024231'9 581.0000 .02-42750 S82. 0000 .t124H86 583.00 00 . 0243623 584.0000 • 024 4059 585.0000 • 02'94496 586. 0000 . 0244932 '>87 . COOO .Ol45368 58A .OOOO .0245805 589.0000 . 02'96241 590.0000 • 02466 7 7 591 . 0000 .. 0247114 592 . 0000 .02 47 550 593 . 0000 .0247<187 594 .oooo .024ts423 595.. 0000 .. 0248859 596.0000 .024929~ 59 ·1. 0000 .021,4n2 59H. 0000 .0250169 599.0000 • 0250605 600.0000 . 0251041 601. 0000 -0251478 602. 0000 .OZ~>l'H'i f>03 . 0000 .02'>1350 604 .. cooo . O;J:52787 605.0000 .. 025)223 606. ocoo . 0253660 607. 0000 .0254096 60'i .OOOO .02S45'\2 609.0000 .0254i69 610.0000 . 0255405 611 .. 0000 .0255841 612.0UOO .0256218 6 ll. 0000 . 0256'14 614.0000 . IJ2'i7l'>l 615.0000 .0257581 616. 0000 . 0258023 617.0000 .0258'960 618.COOO . 0758896 619 . 0000 .0259333 620.. 0000 .. 0259769 621. 0000 • 0260205 622.0000 .0260642 623 .. 0000 . 0261078 62'4 . 0000 . 0261 5 14 625.0000 . 0261951 626.0000 -0262387 627.0000 • 0262H24 b28 . 0000 .. 0263260 629.0000 • 0263696 6)0.0000 • 02641 33 631 .. 0000 . 0264569 632 .. 0000 . 0265005 633.0000 .0265442 634.COOO .026587A 6)5~0000 -0.26f!315 616. 0000 .0266751 637.0000 .. 0267l87 638.COOO .0267'124 l.d9 . 0000 • 02.680b0 640 .0000 . 0268497 64 1 .0000 • 02(,8933 641 . 0000 .0169369 64 '] . 0000 • 0269806 644 .oooo .0270242 645 . 0000 . 0270618 646. 0000 • 0271 ll s 64 7. 0000 • 02 71 55 1 648.0000 .0271988 649 .. 0000 . 0272424 650. ouoo • 0272860 651.0UOO .027329 1 b52. ooou .027 H33 653 . 0000 .. 0274169 ti'H.0000 . 02 74606 655. 0000 . 0275042 656.0000 .02 75479 6S7.0000 . 0275915 658 .0000 .0276351 659 .oooo .02 767 88 660.. 0000 .0277224 661 . 0000 .0277661 b62. 0000 . 0 178097 (,6 ']. 0000 .. 0278S33 664. 0000 .0278970 66S.OOOO . 0274406 666. 0000 .02 74d42 66 7. 0000 0280279 66,_.oooo .. 0280715 669 .oooo . 02811S1 670.. 0000 .0?81S88 671. 0000 • 0282024 6 72. 0000 .0282't6l 6 73 . 0000 .0282897 674 . 0000 .0283333 b7S .OOOO . 0283770 676.0000 .028 ,. 206 6 77. 0000 • 028.\61t3 678.0000 .028so19 6 79.0000 .028551 5 680.0000 .0185<152 681. 0000 .028638'8 681. 0000 . 0286825 683.. 0000 .0287261 684 . 0000 .U287b97 685.0000 .028& 13'4 686. 0000 .0288570 687.0000 .0289006 688.0000 •. 02H9443 689.0000 . 0289879 690.0000 . 0290316 691 . 0000 .0290752 692 .oooo .. 02911 88 693 . 0000 .029 162 S 694 . 0000 • 07920bl 695.0000 .0292497 696 . 0000 • 0292934 697 . 0000 102q3}70 698. 0000 . 07.~3801 6<19.0000 .0291t243 700.0000 . 029't679 701. 0000 .. 02951 16 102. 6oco . 0195552 703.0000 .. 0195989 70-4. 0000 . 1)296425 105.. 0000 • 0296861 706.0000 . 07.97298 707. 0000 . 0291734 708 . 0000 .0298170 709 . 0000 .0298607 710.0000 .0299043 711 .0000 • 0299480 112.0000 .0299916 713.0000 . 0300352 714.0000 .0300789 715.. 0000 .0301 225 716.0000 .030 166 1 71 7. 0000 • 0302098 7l8.0000 .030?534 719. 0000 • 0302971 120. 0000 • 03034 07 7 21.0000 .OlO lAltl 122 .0000 . 0304280 123.0000 .03047 16 724.0000 .0305153 725.. 0000 • 0305589 726. 0000 .0106025 727.0000 • 0306462 728.0000 • 0306898 72q.oooo .0307334 730 .0000 . 03071 71 731 . 0000 • 0]Qij2Q7 n2.oooo .03086'44 733 .0000 .0109080 734. 0000 . 0309516 7)5. 0000 . 0309953 736.0000 .0310389 737.0000 .0310825 738. 0000 . 0311262 739. 0000 .Olll698 740. 0000 7-45.0000 .0312 1 35 . 0314317 741.0UOO 746. 0000 . 03 125 7 1 .03 14753 742 . 0000 7'47.0000 .03 13007 .0315189 743.0000 748.. 0000 .Oll 3444 .Oll'i626 744. cooo 14q.oooo .0313880 .0316062 750.000U . 03l6't98 751. 0000 .03169 35 752 . 0000 .0]17371 753 .0000 .. 0317808 7'i4. 0000 . 03182.C,4 755.000U -0318680 756.0UOO . U3 19l l 7 7'i 1.0000 .0319553 758.. COOO .0319989 759.0000 • 032042b 760.0000 .Ol20b62 761 . 0COO .l.1)21299 76? . 0000 .0321735 763.0000 .0322171 764 . oooo .0322608 765. 0000 .0323044 766. 0000 . 032348 1 761.COOO .0323917 768.0000 .. 032't353 769 . 0000 • 0324 790 770. 0000 .0325226 7 71. 0000 .0325662 112.0000 .0326099 773.0000 .0126535 774 .0000 .0326972 77'5.0000 .0327"08 776.0000 .0127844 777.0000 .0328281 778.·0000 .0328717 77.9. 0000 .0329153 780. 0000 • 0329'i90 781.0000 • 0130026 7132. 0000 .0310463 78.3.0000 .03308"99 78'4.0000 • 0331 335 785.0000 .0331112 786.0000 . Ol322 08 ltH . 0000 .0332645 788. 0000 .0333081 789.0000 .0133517 790.0000 • 031395'4 7'11.lJOOO . 0334390 792. ooou ~ 0334ti26 793.. 0000 .0335263 791t. 0000 .033569.9 795.0000 .01l61 l6 79f..00'J0 . 033ti572 19 1.0000 .0337008 798. 0000 .0137445 799. 0000 .0)37881 Changes in Carbon Dioxide Concentration From Changes in pH TABLE ~Continued TEMPERATURE 25.80 550. 0000 .0227857 551. 0000 .0228291 552.0000 .0226125 553.0000 .0229159 554.0000 • 0229593 555.0000 . 0230027 556. 0000 .0230461 557.0000 .0230895 558.0000 .0231329 559.0000 .0231763 560. 0000 .0232197 561.00CiO .0232631 562.0000 .0233065 563. 0000 .0233499 56.ft .oooo .0233933 565.0000 .0234367 566. 0000 . 02.31.801 567.0000 .0235235 568.0000 .0235669 569. 0000 .0236103 !HO.DODO .0236537 5 7L. 0000 • 0236971 572.0000 .02371t05 573.0000 .. 0237839 571t.OOOO .0238273 575.0000 • 0238707 5 76. 0000 • 0239142 577.0000 .0239576 578.0000 .0240010 579.0000 .021t01t44 580. 0000 .0240878 581.0000 . ·0241312 582.0000 .02(,1746 583.0000 .0242180 584.0000 .0242614 585.0000 .0243048 586. 0000 .0243482 587.0000 .0241916 588.0000 .0244350 589.0000 .024478.ft 590.0000 .0245218 591. 0000 .0245652 592. 0000 .0246086 593. 0000 .02't6520 594. 0000 • 021t6954 595. 0000 .021t7388 596. 0000 . 0247822 597.. 0000 .021t8256 598.0000 .021t8690 599.0000 .021t9121t 600.0000 • 021.i9558 601.00<'0 • 0249<)92 602.0000 .0250~26 603.0000 .07.50860 604.0000 .0251294 605. 0000 .0251728 606.0000 .0252162 607.0000 .0252596 608.0000 .0253030 609.0000 .0251464 610.0000 .0253898 611.0000 .0254332 612.0000 .0251t766 613.0000 .0255201 614.0000 .0255635 615.0000 • 0256069 616. 0000 • 0256503 617.0000 .0256<)37 618.COOO .0257371 619.0000 .0257805 620.0000 .0258239 621 .0000 .0258673 622. 0000 .0259107 623.0000 .025951tl 624.0000 .0259975 625. 0000 • 0260409 626. 0000 • 0260841 627.0000 .0261277 628. 0000 .0261711 629.0000 .026211t5 630.0000 .026257"1 631.0000 .0263013 632.0000 .02631tlt1 633.0000 .0263881 631t.OOOO .0264315 635.0000 640.0000 • 0264749 .0266919 636. 000.0 60.0000 .0265183 .0267351 637.0000 642. 0000 .0265617 .0267787 638.COOO 641.0000 .0266051 .0268221 639.000Q 64't .oooo .0266485 .0268655 6'95.0000 • 0269089 646. 0000 .0269523 647 .0000 .0269957 648.0000 .0270391 649.0000 .0270825 650. 0000 • 027l259 651.0000 .0271694 652.0000 .0272128 653.0000 . 0272562 654.0000 .0272996 65"5. 0000 .0273430 656.0000 .0273864 651. 0000 .0274298 65fl . OOOO .0274132 659.,0000 .0275166 660. 0000 • 0275600 661.0000 • 027603• 662 .oooo .0276468 663. 0000 .0276902 664.0000 .. 0277336 665. 0000 .0277770 666.0000 .027820• 66 7. 0000 .0278638 668.0000 .0279072 669.0000 • 0279506 610. 0000 .0279940 671.00QO. • 02103 74 672.00UO .. 0280808 673.0000 .0281242 671.i .0000 .021Sl676 675.0000 .0282110 676. 0000· .' . 0282.Slt4 6 77. 0000 .028 2978 678.0000 .0283412 679.0000 .028381t6 680.0000 .0284280 681. 0000 .02e•114 682. 0000 .0285148 683. 0000 .0285582 684.0000 .0286016 685.0000 • 0286450 686. 0000 • 0286884 687. 0000 . 02873 18 688.0000 .0287753 689.0000 .0288187 690.0000 .0288621 691.0000 • 0289055 692 .oooo • 0289489 693.0000 .0289923 694. 0000 • 07.90351 695. 0000 • 0290791 696. 0000 • 029122.S 697.0000 .0291659 698.0000 .0292093 699.00QQ . 0292'>27 100.0000 • 02'1296 l 701. 0000 .0293395 702. 0000 .0293829 703. ooco .0294263 704. 0000 . 0294697 705. 0000 .0295131 706.0000 • 0295565 707. 0000 .02'15999 70H. OOIJO . 02<16433 10? .oouo .u?l.16867 110.0000 . 0297301 711.0000 .0297735 712.0000 .0298169 713.0000 . 02'18i'>03 714.COOO • 02"99031 7l5.0000 • 02994 71 716.0000 • 0299905 717..0000 .0300339 718. 0000 .0300773 719.0000 .0301207 720. 0000 .0301641 121.0000 .0302075 122.0000 .0302509, 723.0000 .030291.i3 724 .oooo .O }OJ) 17 725.0000 . 0303812 726. ooou • 0304246 727.0000 . 0304680 728.0000 .0305114 729.0000 .03U5548 730.0000 • 0305982 731. 0000 . 0306416 732.0000 .0306850 733.0000 .0307284 73"'.0000 . 0301718 735.0000 .0308152 736. 0000 • 0308586 73 7. 0000 .0309020 738.0000 . 0309454 719 . 0000 .ll30'Hl88 740.0000 .0310322 741.vUOO .0310756 742.0000 .0311190 ·r1.i1.oono .0311624 744 .oooo . 0312058 745. 0000 .03124q2 146. GCOO .u312926 747. 0000 .OH 3360 74a..onoo .0113794 749.0000 .03l4l28 750.0000 . 0314662 751.0000 • 03 l 5096 752. 0000 . OH 5530 753.0000 .0315964 754.0000 .0316398 755. 0000 • 03 168 32 756.. 0000 .OH 7266 75 7. 0000 .0317700 758 .. 0000 .OH8l31.i 759.0000 .. 03lH568 760. 0000 . 0319002 76l.0000 .0319436 762.0000 .031987l 763.0000 .0320305 164. 0000 .0120 '3<1 765.0000 .03211"13 766. 0000 • 0321607 161. 0000 .032201.il 768.C OOO . 0322475 769. 0000 .032.2909 770. 0000 . 0323343 111.0000 .0321777 112.0000 .0324211 773.0000 .0324645 174.UOOO .u325079 775.0000 7-80.0000 .032551) . 0327683 7 76. 0000 ffJl.0000 . 0325947 .0328ll7 777.0000 782.0000 .0326381 .0328551 178. 0000 783.. 0000 .0326815 .012~985 779.COOO 784 . coco .012 r24q .0329419 785.0000 .0329853 Hs6.0000 . 033028 7 787.0000 .0330721 788 . 0000 .0131155 789. 0000 .tJ33158~ 790.0000 . 0332023 7'11.0000 .0332457 792 . 0000 . 033289l 793.0000 .033332S l (H .OOUO . v3H759 795.0000 .0334193 796. 0000 .0334627 797 .oooo .0135061 798.oono .0335495 799. 0000 .01J'jC130 TEMPERATURE 26.00 550.0000 • 0226492 551.0000 .02269 24 552.0000 .022135$ 5 53.0000 .0227787 554 . 0000 . 0228219 555.0000 .0228650 556.0000 "022?082 55 7. 0000 .. 022~514 558.CO\>O .0229945 559.COOO .07.30377 560. 0000 .0230809 561.0000 .02 31240 562. 0000 .0231672 563.0000 .0232104 564 . cooo .0232535 565.0000 .0232967 566.0000 .0233]<19 56 r.oooo .02n~no 568.0000 .0214262 56<1.0000 .0234691.i 570.0000 .0235125 571.0000 .07.35557 572.. 0000 .0235989 573.0000 .0236420 574.0000 .0?36852 575.0000 .0237284 576.0000 .0237115 571.0000 .023814 7 578.0000 .023/:1579 5.,9.0000 .U23iiOlO 580.0000 . 0239442 581.0000 • 02398 74 582.0000 .0240305 583.0000 .0240737 581.i.OOOO . 07.4l 169 585.0000 .0241601 ·586. 0000 .0242032 58 7.0000 • 0242464 588. cooo . 0742896 589.0000 .021.i3327 590.0000 .0243759 591.0000 .0244191 592,. 0000 . 0244622 593. 0000 .02450S4 594 .0000 .024".i486 595.0000 .0245917 596. 0000 .024634Q 597" OQ(j() .0246 78 l 59H.OOOO .0247212 5<19.0000 . 0247644 600.0000 .0248076 601.0000 . ()248507 t.Ol.00f)Q .0248939 603.0000 . 024~311 604. 0000 • 0249802 605.0000 • 02502 34 606. ocoo • 0250666 601.0000 .0251097 608.COOO .07.51 529 609 . 0000 .0251961 610.0000 .0252392 611.0000 • 0252824 6 12. 0000 .0253256 613.0000 .U25lf.i8 r 614 . 0000 .u254l l9 .615.0000 .025455 1 616.0000 • 0254982 61 7.0000 . 0 255414 6 l 8. cono .0255846 619.0000 • oi562 77 620. 0000 .0256709 621. 0000 . 0257141 622. 0000 . 0257572 623 . 0000 . 02511004 624. 0000 .025t:l4]6 625.0000 • 0256H6 7 626.0000 .025"12'119 627.ooun .025'H3 l 62!3.00UO .07.60162 · 629~ coon .0260594 630.0000 .0261026 631.0000 .02b l457 632.0000 .02618Rq 633 . 00UO .0262.l2 l 614.0000 .. 0262752 635.0000 .0263184 636.0000 . 026lbl6 637.00GO .0.264048 638.COOO .07.644 79 639.0000 .0264911 640. 0000 .0265343 641 . 00(10 .02(.5774 bl.i2. 0000 .0.266206 643.0000 . CJ266639 644 ~ 0000 .0267069 61t5.0000 .0267501 646. uooo .. 0267'133 64 7. 0000 . 0268364 64fi.OOOO .0268796 64':1.0000 .02697.28 650. 0000 .0269659 651 . 0000 .02 10091 652 . 0000 .t,)2/0523 653.0000 .0210954 654. 0000 . 0271U6 655.0000 .0271818 656. ooco • 0272249 657.0000 .0272681 658.COOO .02 73ll 3 659. 0000 • 0213544 660. 0000 .0273976 661 . 0000 . 0274408 662.0000 .0274H39 663. 0000 .0275211 664. 0000 .0275703 665.0000 .0276134 666•. 0000 . 0276566 667. 0000 .02 76998 668.0000 .0271429 669.0000 • 0217861 670.0000 . 0278293 6 71. 0000 .0276724 672.0000 .02 79156 673.0000 .0279589 674.0000 .0280019 675.0000 • 0260451 6 76. 0000 • 02H088 3 677 . 0000 .0261314 678. COOO . 0281746 679.0000 .0282178 680. 0000 . 0282609 681.0000 .0283041 682.0000 .0283473 683.000U .0283904 684 .. 0000 .0784336 685.0000 . 0284 76t:I 686. 0000 . 0285200 68 7. 0000 . 0285631 68R.COOO .0286063 689 . 0000 .0286495 ().90.000Q .0286926 691.0000 .0287358 692:. 0000 .0281790 693. 0000 .0288221 69't. 0000 .lJ288653 695.oooo • 028908 5 696.0000 • 0289!:> 16 6':17 .. 0000 • 0289948 t.9a. 0000 . 0290380 699.0000 .. u?901:ll l .100.0000 .0291243 701. 0000 . 0291675 702.0000 .0292106 703.0000 . 0297.538 704. cooo .0292970 705. 0000 • 029340 l 706 .. 0000 .0293833 701. 0000 .0294265 708.00UO .02"14696 709. 00CJO .0?"15128 110.0000 .0295560 111.ooou . 0295991 7l2.0000 • 02q6423 711.0000 .0296855 7l4.0000 . 02Q7J.86 715.0000 • 0297718 716.0000 .0298150 717.0000 .0298581 718. 0000 .0299013 719.0000 .0299445 720. 0000 .0299876 721.0000 • 0300308 122.0000 .0300740 723.0000 .0301171 724. 0000 . 030 1603 725.0000 .0302035 726.0000 • 0302466 121 .. 0000 .0302898 .72A.OOOO .0103330 729.000U .030.H61 730.0000 .030"4193 731. 0000 .0304625 732.0000 .0305056 7)).0000 .0305488 734.0000 • 03oo;920 7.35.0000 . 0306351 736.0000 .0306783 737 .. 0000 .0307215 na.oooo .030764 7 739.0000 .030d078 740.0000 .0308510 74 l.0000 • 0 308942 74:£".0000 .030Q373 743.0UIJO .(1309805 744.0000 .0310237 745.0000 .0310668 746.0000 .OHllOO 747.0000 .0311532 /48.0000 .0Hl96"l 749.0000 .01121 '15 750. 0000 .0312827 751. 0000 .0313258 752 . 0000 .OH 3690 753 .. 0000 .0314122 754 .oooo .0314!:>>3 755.0000 .0314985 756.0000 . 03154 1 7 757 .. 0000 .0315848 759.0000 .0116260 759. 0000 .0316712 . 760.0000 .0317143 761.0000 .0317575 762. 0000 .0318007 763.000U . u U843H 764. 0000 .OHl)ri7n 765.0000 .0319302 766. 0000 • 03lq133 767.• 0000 .0320165 76R.COUO .0320597 769.0000 .0321028 110.0000 • 0321460 771. 0000 • 0321892 112. 0000 .0322323 773. 0000 . 0322755 174.0000 .1)32316., 775.0000 .0323618 776.00CO . 0324050 777.0000 .0]24482 7713.0000 .Ol249l3 71'l.OOOO .u32SJ4 5 780.0000 . 0325777 781.0000 .0326208 .167.. 0000 • 0326640 783 .0000 .0321072 704.0000 .0127503 785.0000 .0327935 786.0000 .0328367 787.0000 .0328198 788.0000 .03?9230 789.0000 .0329662 790. 0000 .033Q09'\ 791.0000 .0330525 792. 0000 .0330957 793.0000 .0331389 794. 0000 .03llt~20 795.0000 .0332252 796. 0000 . 0332684 "(97.0000 . 0333115 798.0000 .0333547 7"19.COOO .01 3397<1 Changes in Carbon Dioxide Concentration From Changes in pH T ABLE 3-Continued "I EMPERAT URE 26 . 20 550.0000 .0225127 551 . 000U .0225557 552 . 0000 .0225986 553.0000 . 02264l 5 554 . 0000 • 0226845 555 . 0000 .02272 74 556. ocoo . 0227703 557.0COO . 0228133 558. 0000 .0228562 559 . 0000 . 0228991 560. 0000 . 0229420 561.. 0000 . 0229850 562. 0000 .0230279 563.. 0000 . 0230708 564 .oooo .023ll38 565 . 0000 .023156 7 566. 0000 .. 02H996 567.0llOO .• 0232426 568.0000 . 023285'5 569.0000 . 0233284 570.0000 5 7 5. 0000 . 02337 14 .0235860 571.0000 576.0000 . 0234143 . 0 7. 36290 572.0000 577.CCOO .0234572 .02367 19 573.0000 5 78 . 0000 .0235002 . o:n114e 574.0000 579 . 0000 . 023543 1 . 0237578 580. 0000 . 0238007 561 . 0UOO .0238436 582 . 0000 .0238H66 583.0000 .0239295 584.0000 .0239724 585.0000 .CJ240153 566 . 0000 .0240583 58 7 .0000 .0241012 588.0000 . 0241441 589 . cooo . 024187 1 590 . 0000 • 0242300 591. 0000 • 0242 729 592.0000 .02'93159 593 . 0000 .0243588 !>94 . 0000 .0244017 595 . 0000 .02'9't447 596 . 0UOO • 02't48 76 597 . 0000 .0245305 598 . 0000 .0245735 599 . 0000 .U246164 600 . 0000 • 02't6593 60 1.0000 .02'97023 602. 0000 .0247452 603.0000 .0247881 604. 0000 .024831 l 605. 0000 . 0248740 606. 0000 .0249169 60 7.0000 . 0249599 606 . 0000 .0250028 609.0000 . 0250457 6 10.0000 .0250886 611.0000 . 0251316 612 . 0000 . 025171.i5 613.0000 .0252174 6 14 . 0000 . 0252604 615.0000 . 02 !>3033 616.0000 • 025 3462 617 . 0000 .. 0251892 616 . 0000 .0254321 619.0000 .0254750 620 . 0000 .0255180 621 . 0000 . 07.55609 622.0000 • 0256038 623 . COOO • 02 56468 62 't .OOOO • 0256897 6 25 . 0000 .0257326 626. OOCJO . 0257756 617.COOO .0258185 628.0000 . 0258614 629. 0000 • 0259044 630 . 0000 • 0259't 7 3 631 . 0000 .0259902 6JZ . oono .0260331 633.0000 .Ci26076l 634 . 0000 .02611 90 635. 0000 .026 1619 636. ooco • 0262049 63 7._0900 .0262478 638 . 0000 .0262907 639 . 0000 .0263337 6't0.0000 .V263766 6't l .COOO ;02641"95 642 . 0000 . 0264625 643.000 0 . 0265054 644.0000 . 0265't83 645. 0000 .0265913 646. 0000 • 0266 342 647.0000 .0266771 6 4 8.0000 .026720 1 6 49.0000 .02676 30 650. 00 00 • 0268059 65 1. 00CC .07.68489 652.0000 • 0268'} 18 653.0000 . 0269341 6 54.0000 .. 02697 77 655.0000 .0270206 656. 0000 • 0270635 657.0000 . 0271064 658 . 0000 . 027Ht94 659 . 0000 .0271923 660. 0000 .0212352 661.0000 .0272782 662 . 0000 • 027 3211 6 63 . CO OO . 02736 40 664 . 0000 .027't070 66 5. 0000 • 0274499 666. 0000 .0274928 667.0000 .0275358 6 68.. 0000 .027578 7 669 .0000 .0276216 6 70. 0000 .02U.i646 671 . 0000 .0277075 6 72. 0000 .02 7150• 6 7 3 . 0000 .0277934 6 74 . 0000 . 02 78363 675 . 00 00 .0278792 6 76. 0000 .0279222 617 . 0000 .-02 79651 678.0000 .0280-080 6 79. 0000 .028 051 0 680. 0000 • 0280939 681.0000 .0281368 682 . 0000 .0281. 79 7 683 . 0 000 . 0 282227 684. 0000 .0282656 685. 0000 .0283085 686. 0000 .02835 15 68 7. 0000 • 028 39-'t't 688.0000 .0284373 689 . 0000 .0284803 690. 0000 . 028"1232 691. 0000 .0285661 692 . 0000 . 0286091 693. 0000 .0286 520 694 . 0000 .0286 949 695. 0000 • 028 73 79 696. 0000 .. 02878.08 697 .. 0000 .0.288231 6 9 8.CCOO . 0288667 699 . 0900 • 0289096 700. 0000 . 0289525 101.0000 • 0289955 702 . 0000 .0290384 703 . 0000 . 02908 1 3 704.0000 • 029 12.\2 705 .. 0000 .c2916.72 706. 0000 .0292101 101. 0000 .0292530 108 . 0000 .029296 0 709. 0000 . 029338<1 11 0 .. 0000 . 02938 18 711 . 0000 . 02942.\8 112.0000 • 02<146 77 71 3 . 0 000 .0295 106 714 . OOOCJ .0295536 715. 0000 • 0295965 716.0000 .0296394 717.. 0000 . 0296824 71 8.COOO .02972-;3 71 9.0000 .0297682 720.0000 .02981 1 2 1 2 1. 0000 . 029854 1 122. 0000 • 02q9970 723.0000 .0299400 724 . 0000 . 029?829 725 . 0000 .0100258 726. 0000 • 030068tt 727.0000 .030 11 17 77-fi.0000 .030 1546 729.0000 .0301975 7 30 . 0000 • CJ302405 731.0000 .. 03.0283't 732 . 0000 . 0303263 733.0000 .0303693 734 . 0000 .030't l22 7 35.0000 . 0304 55 1 736 . o·ooo . 0304981 737.00CO . 03054 10 73 8 . COOO . 0305839 739. 0000 . 0306269 740. 0000 • 0306698 741.0000 .0307127 742.0000 .0307557 743.0000 .0107986 744 .oooo .0308415 745.0000 .0308845 746. 0000 .0309274 747.0000 .030<1703 748. 0000 .0110133 749.0000 . 0310562 750 . 0000 .0310991 751.0000 .0111"20 752.0000 .. 03 1 1850 753.0000 .0312279 754. 0000 . 0312708 7 55.0000 .0313138 756 . 0000 . 01 1356 7 757 . 0000 .0313996 758 . 0000 .0314426 759.0000 .0114855 760. uooo .U315284 761. 0000 .0315714 762. 0000 . 0316143 763.0000 . 0316572 764 .0000 .0317CJ02 765.0000 . 0 3l743l 766.0000 .0317860 76 7. 0000 . 0318290 768.COOO .03L8719 769.0000 .0319148 770. 0000 .0319578 111 . 0000 • 0320007 772. 0000 .0320436 773 . 0000 .0320866 774 . 0000 .032 1295 775 . 0000 . 0321724 776. 0000 .0322153 777.0000 .0322583 778 . 0000 . 0323012 779 . 0000 . 0323441 780. OOOCJ .03231Hl 781.0000 • 0324300 782 .. 0000 . 0324 729 783 . 0000 .0325 159 784.0000 . 0325588 785 . 0000 790.0000 .G326017 .0328164 786 . 0000 1q 1 .oooo .0326447 • 0328593 787.0000 1112.0000 . 0326076 . 0329023 788.0000 M3.0000 .0327305 .0329452 78;9.0000 794. 0000 .032 /"f 35 .0329881 795 . 0000 .03303 11 796 . 0000 .0330740 797 . 0000 .0331169 798 . 0000 .013 1599 79q . oooo . 0332028 TEMPERATURE 2b.40 550.0000 .0223763 55 1.0000 • 02241 '-'0 552 . 0000 .0224617 553 . 0000 .0225044 55't.COOO .0225471 555 .0000 .0225898 556. 0001) .0226125 557.0000 .0226752 558 . ooco .Ol27l 79 559 . 0000 .0227606 560. 000 0 . 0228033 561.0000 .0228459 562 . 0000 .0228886 563.0000 .CJ22931 3 564 . 0000 . 022"740 565.0000 .0230 167 566. 0000 .CJ230S94 56 7.0000 . 0211021 568.00CO .oz 31446 569 . 0000 .0231875 570.0000 .0232302 571.0000 . 02 32129 s 12.ooco .0233156 573 . 0000 .02HS83 574 . 0000 .02340 10 575 . 0000 . 0 234437 576. 0000 . 0 23't864 57 7.COOO .0235291 5 78. cooo . 0235718 579 . 0000 . 0236145 580. 0000 .0236572 58 1 .0000 .o236q1J9 582.00QO • 02 37426 583.0000 .0237853 584 . oooo .0238280 585. 0000 • 02 36 70 7 586. 0000 .0239 1 34 587.00UO .023956 1 586.COGO .07.39~98 5B9.0000 .02404 15 590.0000 • 02408't l 591 . 0000 .0241268 592. ocoo . 0241695 593.0000 .0242 122 594 . 0000 . 0242549 5':l5. 0000 .0242"76 596. 0000 . 0243403 5q1 . oooo . 0243830 'j98 . 0000 .0244257 51:19 . 0000 • 0244684 bOO. OOOU .02't5lll 601.0000 .0245538 602.0000 . 0245965 603.00tlO . 0246392 604 .cooo . 0246819 605. 0000 .0247246 606. 0000 .0247673 607 .oooo .0248100 608. COGO .0248527 609.0000 • 0248954 610.0000 .. 024938 l 6 11. 0000 .. 0249808 612 . 000() .0250235 613.0000 .0250662 614 . 0000 • 0251089 615.0000 .025 1516 6 16 . 0000 .025 1943 617.0000 . 0252 :no 6 18 . 0000 . 0252797 619 . 0000 . 0251223 620 . 0000 . 0253650 621 . 00CtO • 0254077 622.0000 . 0254504 623 . 0000 .0254911 6i4.0000 . 0255358 625. 0000 . 0255785 626. 0000 .0256212 627.0000 . 0256639 628 . COOO . 0257066 62(} .. 0000 . 07.57493 6 30.0000 .025 1920 631 . 0000 .0258347 632.0000 .0258774 631.00GO . 0259201 634.0000 .0259626 635.0000 6't0. 0000 645 . 0000 650 .. 0000 655.0000 660.0000 665.0000 6 70.0000 675 . 0000 680. 0000 685.0000 6QO. 0000 695. 0000 .026.0055 . 026 2190 .0264325 . 0 2664 5(} .0268594 . 027072<1 .0272864 .0274-199 .1)271134 .0279268 . 0 281403 . 0263538 .0785673 636. ooeso 6 4 1 . 0000 646 . 0 0 0CJ 65 1.0000 656. 0000 661.0000 666 . 0000 671 . 0000 676. 0000 681.000CJ 686.0000 691.0000 696 . 0000 . 02604tf2 .02626 17 • 0264 752 • 0266806 .. 026902 1 .CJ27ll56 . 0273291 .0275426 . 0277~61 • 02 79b95 . 0281830 • 0283965 .0286100 63 7. 00(10 6't2. OOGO 64 7 . 0000 652 .0000 657.COOO 662. 0000 667.0000 672.0000 611. 0000 682 . 0000 687 .. COOO 6(}2 . 0000 697. 0000 .0260909 .026304't .026'il 79 . 026 7 313 . 0269448 .0271583 .02731 18 . 0275853 . 0277988 . 0280122 . 028225 7 . 0284392 .0286527 638 . 0000 6't'l.OOOO 64~ . oooo 653 .. 0000 658.0000 663.0000 666. 0000 6 7 3.0000 ·678 . 0000 683.0000 688 .C OOO 693.0000 698 . 0000 .0261136 .0263471 . 0265606 .0267740 .0269875 . 0212010 .0274145 .02 76280 . 02784 14 .0280549 .0282684 . 0284819 • 0286954 639 . 0000 644 .oooo 64(} . oooo 654. 0000 659. 0000 664 .. 0000 669. 0000 6 74 . 0000 679.0000 684 .. 0000 689. 0000 694.0000 699. 0000 .0261763 .02638'118 . 0266032 . 0268167 .0270302 . 0272437 .02745 72 .0276707 .027884 1 .0280976 .0283111 . 02'85246 . 0287381 700.0000 . 0287H08 101.0000 .0288235 702 . 0000 .0288662 703 . 0000 .0289089 704~0000 . 020·95 16 705.0000 ~ 028994 3 706. 0000 • 0290370 707 .oooo .0290196 708 . 0000 .O.a9 1223 709 . oooo .0291650 110.0000 • 02920 7 7 111.0000 • 021:12504 712. 0000 .0292931 713.0000 . 0293358 714 . 0000 :07.93785 715. 0000 . 02942 1 2 716. 0000 .029463Q 111 .oaoo . 0295066 719.0000 .0295493 719. 0000 • 0295920 1 20.0000 • 029634 7 121 . 0000 • 0296 774 122.0000 .0297201 723 . 0000 .0297628 724.0000 . 0298055 725 . 0000 • 02<18482 726. 0000 • 0298909 727.0000 . 0299336 728. 0000 .0299763 729 . 0000 .0300190 730. 000() .. 0300617 731 . 0000 .0301044 732.0000 .0301471 733 . 00IJO •. 0101898 734 . 0000 .0302325 735.0000 . 0302 752 736. 0000 . 0303178 737.0000 . 0303605 738. 0000 . 010'•032 739. 0000 • 0304459 74 0 . 0000 .0304686 74 1.0000 .0305313 742 . 0000 . 0305740 743.0000 . CJ30l..167 744 . 0000 • 0306594 745.0000 .0307021 746. 0000 • 030 7448 747.0000 .03078 75 748.0000 .0308302 749.0000 .0308729 750.0000 .01oql56 75 l. 0000 .030958.3 752 . 0000 . 0310010 7'>3.0000 .0310437 754. 0000 . 03 10864 755. 0000 .0311291 756. 0000 . 0311718 ·151.0000 .0312145 758. cooo . 0312572 759 . 0000 . U3l2999 760. 0000 • 0313426 761.0000 .0313853 762 . 0000 .0314280 763.0000 .. 03 14707 764 . 0000 .0315134 76 5.000CJ .0315561 766. 0000 . 03 1598 7 767.0000 .03 16414 76·8 .COOO .0316841 769 . 0000 . 0317268 770. 0000 .0317695 771 . 0000 .0318 1 22 11 2.0000 .0318549 77,3 . 0000 .0318976 774.0000 • 03 l 9403 7 75.0000 .0319830 776. 0000 . 0320257 777.0000 .0320684 778 .'0000 .0321 l l l ·119. 0000 . 0'32l538 780 .0000 .0321965 781. 0000 .03223(}2 782.0000 . 0322819 783.0000 . 037.3246 784. 0000 . 0323673 7 85. 0000 . 0324100 786 . 0000 . 032452 7 787.COOO . 0324954 788.0000 .0325381 789. 0000 .0325608 790. 0000 .0326235 791.0000 • 0326662 797.. 0000 . 032 7089 793.00VO . 0327516 794 .oooo .03271:1 4 3 795.000ll .. 0328369 796. 0000 .0328796 .7q 7. 0000 .0329223 798 . 00GO .0329650 799 .oooo . 0330077 Changes m Carbon Dioxide Concentration From Changes in pH TABLE 3-Continued TEMPER ATURE 26.60 550. 0000 .0222399 55 l. 0000 .02 22824 552.0000 .0223248 553 . 0000 .022367) 554 .oooo .0224111.J!t 555.0000 . 0224522 556.0000 .022,.947 55LOOOO .022537l 558 . COOO . 0225796 559.0000 . 022622l 560.0000 .0226645 561 . 0000 . 0227070 5t..2 . cooo .0227494 563. cooo .0227419 564.0000 .l.12211344 565.000U • 0228 768 566. 0000 • 0229193 56 7. 0000 .1)2296 1 7 568 . 0000 .0210042 569. cooo .0230467 570.0000 .0230891 571.0000 .023 1316 572.0000 . 023l71tl 513.0000 .0232165 S74.0000 • 023ZS26 'Hl0 653 . ooco .0266134 654 . 0000 • 0266559 655. 0000 .0266983 656. 0000 • 0267408 65 7 . 0000 .0267833 658 . 0000 . 0268257 659. 0000 .0268682 660 . 0000 .0269106 661. 0000 .0269531 662. 0000 • 0269956 661. 0000 .02 70380 664 . 0000 .0270005 665.0000 .0211229 666. ocoo .0271654 667.0000 .027 20711 668. 0000 .0272501 669. 0000 .0272928 670.0000 .0273353 671.CCOO .0211111 672.UOOO .0274202 673.0000 .oz 7"626 6 74. cooo .0275051 675 . 0000 .02"75476 676.0000 .0275900 677.0000 .0276325 678.COCO .0276749 679.COOO .02111 74 680. 0000 • 0217599 681.0000 .0278023 t.82.0000 .0278448 683. coco . 027887) 684. 0000 .02N297 685. 0000 • 0279722 6H6.UOOO • U280146 687.0000 . 02h057l 688 . 0000 .02809q6 689. COJO .0281420 690.0000 .0281845 691. 0000 .0282269 692.0000 . 021:12694 693.00CO . 02R3119 694 .oooo • OZR 1';43 695.0000 • 0283968 696. 0000 .07tl4392 697 . oooo .02841:Sl 1 69~. oooo . 0285242 6'#9. 0000 . 0285ti66 700. 0000 • 02860"1 l 101. 0000 • Olb6516 702 .0000 • 02869lo0 101. onoo . 0.?6736"; 704 .onoo .u2~77tH 705.0000 • 0288214 706 . 0000 • 0288639 101. 0000 • 0289063 708. 0000 .0289488 709 . 0000 .028"1'112 710.000U .0290331 71 LVOOO . ()290762 112.0000 .02"1 1186 713 . 0000 .07.91611 714. 0000 .u2'120l"; 715 . 0000 • 02~2460 716. 0000 • 02ci­2.aa5 717 . 0000 .0293309 HA.0000 .029'.\734 7 19 . 0000 .0?941~<1 120. 0000 . 02Q4581 72 1. 0000 • 0295008 722.0000 .029'H32 723 . 0000 .029'>8~7 724 . GODO ~0796282 725.0000 • 0296 706 726.0000 . 0297131 727. 0000 .0297555 7l8.0U1JO .02'17980 729 .oouo .u7"84lJS 7)0 . 0000 .0298829 731 . 000U .0299l54 732. 0000 • 029'167'1 7B.OOuO .0300103 734 . 0000 .1nnos2a n5.oooo .0300952 736 . 0000 .0301377 H7.0000 .0301802 738 . 00VO . 0107226 719 . C0'>0 . u102651 740.0000 . 0103075 741.0000 .OJOl500 742. coco .0303925 743.0000 • 0304349 744 . 0000 • 0304174 745.0000 .uJ05198 746. 00110 . 0105621 747.0000 .0306048 148.0000 .03064 72 749.0000 .03068~7 750. 0000 • 0307322 751.0000 . 0307746 752.0000 .0308111 753 . 0000 . 0308595 754. 0000 • 0)09070 755. 0000 . 0309445 756. 0000 • 0309869 757.0000 .0310294 158 . 0000 . 0310718 759. cooo .OH 1143 760 . 0000 .03115613 76 1. uuou .o3l l 'i192 762 . 000(1 .0312417 763.000Q .0112t142 764. 0000 . 0313266 765. 0000 .031369 1 766. 0000 . 0314115 167.0000 .03 14540 768. 0000 .0114965 16a. cooo .()3153!!9 770. 0000 .0315814 171. 0000 .0316238 772 . 0000 .0316663 773.001)0 . 0317088 714 . 0000 . 0311512 7 75 . 0000 . 0317937 7 76. 0000 • 03 18361 717 . 0000 . 03ltl l 86 778. 0000 . 031921 l 779 . 0000 . •J3196)'j 780. 0000 .0320060 78 1.0UOO .0320485 182 . 0000 . 0120909 783.0000 .0321334 784. 0000 .0321758 78'i. 0000 .OJ221RJ 786. coco . 0122608 787.0000 .032"\032 7R8 . COCO . 0123457 789 . 0000 . 0123dtH 790 . 0000 • 032430f:J 791. Ot:OO .0)24731 7-17.COOO .0325155 193 . 0000 .0325580 7~4 . 0000 .U326U04 795.0000 .032642'1 796.. 0000 . 0326854 797 .0000 .0327278 793.0000 .0327703 799 . 0000 . 0328128 TEH PERA TURE 26 . 80 550.0000 .0221035 551.Gt:OO .027.1457 552 . 0000 .022 lsao 553.0000 .0222102 554 . cooo . 0222724 555.0000 .0223146 5Sb . OOOO • n22 3569 55 7. 0000 .0223991 558 . 0000 .0224413 559.0000 .0224835 560. 0000 .02252S8 56 1. 0000 • 0225660 562 . 0000 .0226 102 563 . 0000 . 0226524 564 . oooo .072694 7 565.0000 .0227369 566. 0(11.iO . 0227791 567.0000 . 0228213 568 . 0000 . 0278h36 569 . 0000 .0224058 5 70 . 0000 • 02294HO !\71 . COOO .0229903 5 71 . 0000 .021o:ns 573.0000 .0230747 5 74. 0000 .0231169 575. 000 0 .0231592 5 76. 0000 . 02320 14 577.CCCO . 0232436 57R.0000 .0217858 579 . 0000 . 023321;11 580. 0000 .0213/03 58 1. 0000 .0234125 582. 0000 . 023454 7 583.0000 .oz 34'170 584 . 0000 .0235392 585.0000 .023!>814 586. 0000 . 0236236 5ts7 . COOU .0236(.59 588 . 00CO . 0237081 589. 0000 .0237';0) 590. 0000 . 0217925 591.0000 .0238348 592. 0000 .02387 70 593. 0000 .0239192 594 . 0000 • 0239t.1" 595. 0000 • 024003 I 596 . 0000 . 0240459 59 7. cooo . 0240881 598.0000 .0241304 5'19. 0000 .024 1 726 600. 0000 .0242148 601.0000 • 0242570 602 . 0000 • 0242993 601 . 0000 .0243415 604 . oooo .0243837 605.0000 . 0244259 606.0000 . 0244682 607.0000 .0245 104 608 . 0000 .024)526 609.0000 • 0245948 610. 0000 • 024637 l 611.001.iO . 0246793 6 12.0000 . 0247215 613.0000 . 0247617 6llo.COOO • 024tfl.i60 615. 0000 .0248482 616. 0000 .0248'1104 6 1 7. COOO .0249326 618.00IJQ .024974'1 6 19 . 0000 . 0 250 1 71 620. 0000 .02S0';93 621.001.iO . 0251015 622.0000 .0251438 67.3.00(iO .0251860 624.0000 .0252282 b25. 0000 . 0252705 626. coco .0253127 62 7. coco .0253549 626.00(,0 .0253971 629.COOO . 0254194 630. 0000 .025"816 631.000 0 . 02552)8 632.0000 .0255660 633.0000 .025608) 6l4 . 0000 . 0?";6505 635.0000 640.0ooo 645.0000 . 0256927 .u259038 .0261150 636. 0000 641.UUOO 646 . ccoo . 02:1111o11 .0259461 . 0261512 637.0000 642. 0000 6lo 7. cooo . 0tljf772 • 0259883 .0261994 bl6.CO~W 64~.oooo 64t.cooo .025tH94 .026030lj .0262416 63q.oooo 644 . 0000 649.0000 .0258616 . 016072 I . 0262819 6SO.OOC!O 655.000 0 660.0000 665.0000 6 70. 0000 675. 0000 680 . 0000 685. 0000 690.0000 695.0000 .. 0263261 • 0265 37 2 • 026 7484 • 0269595 .0271706 . 0273tsl 7 .0275929 • 0278040 .0280151 .021:J2263 651. 0000 656. 0000 ()6 1. ocoo 666.0000 671 . 0000 676.0000 681.0000 686.0000 6'11.0000 b9b.OOOO . 0263683 • 0265795 . 0267906 .0270017 .0272128 . 0274240 . 0276351 • 0278462 . 0280574 • 0282685 652.COCO 65 7.0000 662 . 0000 667.COOO 672.COOO 677.0000 682 . 0000 687.0000 692.onno 697. 0000 .0264106 .026621 7 .0268328 .0270439 .0272551 • 0274662 .0276771 . 0278885 . 0280'1196 . 0283 107 653 . COOO 658. 0000 663 . 0000 66P..CCOO 673. 0000 67fl.OOOu 683.0000 686.0000 693. 0000 698.0000 . 0264528 .0266639 . 026£1:750 .0270862 .0272973 .02 75084 . 0277196 .0.?79107 .01814 18 . 02a1s29 654 .oooo 6o;q . oooo 664 . 0000 669. 0000 6 74. 0000 679.0000 684.0000 689 . 0000 694. 0000 699 . 0000 .0264950 .0267061 . 0-169173 . 027128" .. 0273395 . 021o;o;o1 .. 0277618 .0279729 . 0281840 . 0281952 700.00 00 705. 0000 .0284374 .0286485 701.0000. 706.0000 .0284796 . 0286908 102 . 0000 707. 0000 .028~218 703. 0000 . 0287330 708.COCO .028"i641 .0287752 704 . 0000 709 . 0000 ;028606.) .0288174 110. 0000 .0288597 111.0000 .0289019 112.0000 .028'-1441 713.00UO . 07.99863 714.0000 . u290286 715 . 0000 . 02~0708 716.0000 • 0291130 71 7. coco .02'11552 718.0000 .02'11975 719.0000 .0292397 720.0000 • 0292819 121 . 0000 . 0293241 122.0000 .0293664 723 . 0000 .. 0294086 724 .oooo .. 0294508 725. 0000 • 0294q30 726.0000 .0295353 727 . 0000 .ozqsns 728.0000 .0296197 729.0000 . 02966 19 730. 0000 .Q21i110.r.2 73 1. 0UUO • 029 7464 732. 0000 .02'11886 731. 001)0 . 0291'309 7}4.0000 .0298731 735 . 0000 . 0299153 736 . 00110 • 02995 75 737.0000 • 02991f98 7H.OOIJO • 0300420 139 . 0000 .03008.r.2 740. 0000 . 0301264 741.0000 . 0301687 742. 0000 . 030710'1 7"3.00()0 .0302531 744.0000 .0302953 7lt5. 0000 . 0303376 746 . 0000 • 0303798 ·74 7. 0000 .U304220 748. OOGU .01U4h42 749.0000 . 0305065 750 .0000 .0305487 751. 0000 .0305909 752.0000 .030h3H 75 3.0000 .0306754 754 . oooo . 03071 76 755~ 0000 . 0307598 756. 0000 • 0308020 757 . 0000 .0308443 75A. 0000 . 0308865 759 .. 0000 .0109287 760. 0000 . 0309710 761 . 0000 .0310132 762. 0000 . 0310554 "163.00CO .OJ 10976 764 .. 0000 . 03ll399 765 .000U .031182 1 766. 0000 .0,12243 167 . 0000 . 03 12665 768.0000 . 0313088 769.0000 .03 13510 770 .0000 . 0313932 111.0000 . 0314354 772. 0000 .0314777 773 . 0000 .03 15199 7 74 . 0000 . 0315621 775.0000 .. 0316043 776. 0000 . 0316466 777.COOO . 0316888 778.0000 .011731 0 7 79 . 0000 .031 7732 780.0000 .03l8155 781.0000 . 031857 7 782 . 0000 . 0318999 783.0000 .0319421 784 . 0000 .031984" 785.0000 • 0320266 786 . 0000 • 0320688 787 . 0000 .0121111 788.COOO . 0321533 789 . 0000 .0321955 79-0.0000 . 0322377 791. 0000 .0322800 792. 0000 .0323222 793. 0000 .0323644 794 . COOO . 0324066 795.0000 • 0324489 7'16 . UOOO . 0324'11 l 7'-ll. 0000 . 0325333 798.0000 .0125755 799.0000 . 03261 "/8 TABLE4 F factors. These values are calculated from the expression F = /':,. V/V X 1000. These dilution factors are given in 0.1 ml increments for 100, 200, or 300 ml samples up to an F value of 99.0991. F factors are to be multiplied by M or M-X for each increment of titrant added, depending on whether the abbreviated or more accurate equation is to be used. F factor& F factors increment Volume increment Volume of trit.rant 100 200 300 of trit..rant 100 200 300 .1 .9990 .4998 .3332 6.3 59.2662 30.5381 20.5681 .2 1.9960 .9990 .6662 6.4 60.1504 31.0078 20.8877 .3 2.9910 1.4978 .9990 6.5 61.0329 31.4770 21.2072 .4 3.9841 1.9960 1.3316 6.6 61.9137 31.9458 21.5264 .5 4.9751 2.4938 1.6639 6.7 62.7929 32.4141 21.8455 .6 5.9642 2.9910 1.9960 6.8 63.6704 32.8820 22.1643 .7 6.9513 3.4878 2.3279 6.9 64.5463 33.3494 22.4829 .8 7.9365 3.9841 2.6596 7.0 65.4206 33.8164 22.8013 .9 8.9197 4.4798 2.9910 7.1 66.2932 34.2830 23.1195 1.0 9.9010 4.9751 3.3223 7.2 67.1642 34.7490 23.4375 1.1 10.8803 5.4699 3.6533 7.3 68.0336 35.2147 23.7553 1.2 11.8577 5.9642 3.9841 7.4 68.9013 35.6798 24.0729 1.3 12.8332 6.4580 4.3146 7.5 69.7674 36.1446 24.3902 1.4 13.8067 6.9513 4.6450 7.6 70.6320 36.6089 24.7074 1.5 14.7783 7.4442 4.9751 7.7 71.4949 37.0727 25.0244 1.6 15.7480 7.9365 5.3050 7.8 72.3562 37.5361 25.3411 1.7 16.7158 8.4284 5.6347 7.9 73.2159 37.9990 25.6577 1.8 17.6817 8.9197 5.9642 8.0 74.0741 38.4615 25.9740 1.9 18.6457 9.4106 6.2935 8.1 74.9306 38.9236 26.2902 2.0 19.6078 9.9010 6.6225 8.2 75.7856 39.3852 26.6061 2.1 20.5681 10.39()!) 6.9513 8.3 76.6390 39.8464 26.9218 2.2 21.5264 10.8803 7.2799 8.4 77.4908 40.3071 27.2374 2.3 22.4829 11.3693 7.6083 85 78.3410 40.7674 27.5527 2.4 23.4375 11.8577 7.9365 8.6 79.1897 41.2272 27.8678 2.5 24.3902 12.3457 8.2645 8.7 80.0368 41.6866 28.1827 2.6 25.3411 12.8332 8.5922 8.8 80.8824 42.1456 28.4974 2.7 26.2902 13.3202 8.9197 8.9 81.7264 42.6041 28.8119 2.8 27.2374 13.8067 9.2470 9.0 82.5688 43.0622 29.1262 2.9 28.1827 14.2928 9.5741 9.1 83.4-097 43.5198 29.4403 3.0 29.1262 14.7783 9.9010 9.2 84.2491 43.9771 29.7542 3.1 30.0679 15.2634 10.2276 9.3 85.0869 44.4338 30.0679 3.2 31.0078 15.7480 10.5541 9.4 85.9232 44.8902 30.3814 3.3 31.9458 16.2322 10.8803 9.5 86.7580 45.3461 30.6947 3.4 32.8820 16.7158 11.2063 9.6 87.5912 45.8015 31.0078 3.5 33.8164 17.1990 11.5321 9.7 88.4230 46.2566 31.3206 3.6 34.7490 17.6817 11.8577 9.8 89.2532 46.7112 31.6333 3.7 35.6798 18.1640 12.1831 9.9 90.0819 47.1653 31.9458 3.8 36.6089 18.6457 12.5082 10.0 90.9()!)1 47.6190 32.2581 3.9 37.5361 19.1270 12.8332 10.1 91.7348 48.0723 32.5701 4.0 38.4615 19.6078 - 13.1579 10.2 92.5590 48.5252 32.8820 4.1 39.3852 20.0882 13.4824 10.3 93.3817 48.9777 33.1937 4.2 40.3071 20.5681 13.8067 10.4 94.2029 49.4297 33.5052 4.3 41.2272 21.0475 14.1308 10.5 95.0226 49.8812 33.8164 4.4 42.1456 21.5264 14.4547 10.6 95.84-09 50.3324 34.1275 4.5 43.0622 22.0049 14.7783 10.7 96.6576 50.7831 34.4384 4.6 43.9771 22.4829 15.1018 10.8 97.4729 51.2334 34.7490 4.7 44.8902 22.9604 15.4250 10.9 98.2867 51.6833 35.0595 48 45.8015 23.4375 15.7480 11.0 99.0991 52.1327 35.3698 4.9 46.7112 23.9141 16.0708 11.1 52.5817 35.6798 5.0 47.6190 24.3902 16.3934 11.2 53.0303 35.9897 5.1 48.5252 24.8659 16.7158 11.3 53.4785 36.2994 5.2 49.4297 25.3411 17.0380 11.4 53.9262 36.6089 5.3 50.3324 25.8159 17.3600 11.5 54.3735 36.9181 5.4 51.2334 26.2902 17.6817 11.6 54.8204 37.2272 5.5 52.1327 26.7640 18.0033 11.7 55.2669 37.5361 5.6 53.0303 27.2374 18.3246 11.8 55.7129 37.8448 5.7 53.9262 27.7103 18.6457 11.9 56.1586 38.1533 5.8 54.8204 28.1827 18.9666 12.0 56.6038 38.4615 5.9 55.7129 28.6547 19.2873 12.l 57.0486 38.7696 6.0 56.6038 29.1262 19.6078 12.2 57.4929 39.0775 6.1 57.4929 29.5973 19.9281 12.3 57.9369 39.3852 6.2 58.3804 30.0679 20.2482 12.4 58.3804 39.6927 480 Changes in Carbon Dioxide Concentration From Changes in pH TABLE 4-Continued F factors F factors increment Volume increment Volume of lritranl 200 300 of tritranl 200 300 125 58.8235 40.0000 19.l 87.1748 59.8558 12.6 59.2662 40.3071 19.2 87.5912 60.1504 12 7 59.7085 40.6140 19.3 88.0073 60.4447 12.8 60.1504 40.9207 19.4 88.4230 60.7389 12.9 60.5918 41.2272 19.5 88.8383 61.0329 13.0 61.0329 41.5335 19.6 89.2532 61.3267 13.1 61.4735 41.8397 19.7 89.6677 61.6203 13.2 61.9137 42.1456 19 8 90.0819 61.9137 13.3 62.3535 42.4513 19.9 90.4957 62.2069 13.4 62.7929 42.7569 20.0 90.9091 62.5000 13.5 63.2319 43.0622 20.1 91.3221 62.7929 13.6 63.6704 43.3673 20.2 91.7348 63.0856 13.7 64.1086 43.6723 20.3 92.1471 63.3781 13.8 64.~463 43.9771 20.4 92.5590 63.6704 13 9 64.9836 44.2816 20.5 92.9705 63.9626 14.0 65.4206 44.5860 20.6 93.3817 64.2545 14.l 65.8571 44.8902 20.7 93.7925 64.5463 142 66.2932 45.1941 20.8 94.2029 64.8379 14.3 66.7289 45.4979 20.9 94.6129 65.1293 14.4 67.1642 45.8015 210 95.0226 65.4206 14.5 67.5991 46.1049 21.1 95.4319 65.7l16 14.6 68.0336 46.4081 21.2 95.8409 66.0025 14.7 68.4676 46.7112 21.3 96.2494 66.2932 14 .8 68.9013 47.0140 21.4 96.6576 66.5837 14.9 69.3346 47.3166 21.5 97.0655 66.8740 15.0 69.7674 47.6190 21.6 97.4729 67.1642 15.1 70.1999 47.9213 21.7 97.8800 67.4541 15.2 70.6320 48.2234 21.8 98.2867 67.7439 15.3 71.0636 48.5252 21.9 98.6931 68.0336 15.4 71.4949 48.8269 22.0 99.0991 68.3230 l'>.5 71.9258 49.1284 22.l 68.6122 15.6 72.3562 49.4297 22.2 68.9013 15.7 72.7863 49.7308 22.3 69.1902 15.8 73.2159 50.0317 22.4 69.4789 15.9 73.6452 50.3324 22.5 69.7674 16.0 74.0741 50.6329 22.6 70.0558 16.1 74.5025 50.9332 22 7 70.3440 16.2 74.9306 51.2334 22.8 70.6320 16 3 75.3583 51.5334 22.9 70.9198 16.4 75.7856 51.8331 23.0 71.2074 16.5 76.2125 52.1327 23 l 71.4949 16.6 76.6390 52.4321 23.2 71.7822 16.7 77.0651 52. 7313 23.3 72.0693 16.8 77.4908 53.0303 23.4 72.3562 16.9 77.9161 533291 23.5 72.6430 17.0 78.3410 53.6278 23.6 72.9295 . 17.l 78.7655 53.9262 23.7 73.2159 17.2 79.1897 54.2245 23 8 73.5022 17.3 79.6134 54.5225 23.9 73.7882 17.4 80.0368 54.8204 24.0 74.0741 17 5 80.4598 55.l181 24.1 74.3598 17.6 80.8824 55.4156 24.2 74.6453 71.7 81.3045 55.7129 24.3 74.9306 17.8 81.7264 56.0101 24.4 75.2158 17.9 82.1478 56.3070 24 5 75.5008 18.0 82.5688 56.6038 24.6 75.7856 18.1 82.9895 56.9003 24 7 76.0702 18.2 83.4097 57.1967 24.8 76.3547 18.3 83.8296 57.4929 24.9 76.6390 18.4 84.2491 57.7889 25.0 76.9231 18.5 84.6682 58.0848 25.l 77.2070 18.6 85.0869 58.3804 25.2 77.4908 18.7 85.5053 58.6759 25.3 77.7744 18.8 85.9232 58.9711 2S.4 78.0578 18.9 86.3408 59.2662 25.5 78.3410 19.0 86.7580 59.5611 25.6 78.6241 TABLE 4-Continued F facton F factors increment increment or lrilrant Volume 300 of tritrant Volume 300 25.7 78.9070 29.4 89.2532 25.8 79.1897 29.5 89.5296 25.9 79.4722 29.6 89.8058 26.0 79.7546 29.7 90.0819 26.l 80.0368 29.8 90.3578 26.2 80.3188 29.9 90.6335 26.3 80.6007 30.0 90.9091 26.4 80.8824 30.l 91.1845 26.5 81.1639 30.2 91.4597 26.6 81.4452 30.3 91.7348 26.7 81.7264 30.4 92.0097 26.8 82.0073 30.5 92.2844 26.9 82.2882 30.6 92.5590 27.0 82.5688 30.7 92.8334 27.l 82.8493 30.8 93.1076 27.2 83.1296 30.9 93.3817 27.3 83.4097 31.0 93.6556 27.4 83.6897 31.l 93.9293 27.5 83.9695 31.2 94.2029 27.6 84.2491 31.3 94.4763 27.7 84.5285 31.4 94.7495 27.8 84.8078 31.5 95.0226 27.9 85.0869 31.6 95.2955 28.0 85.3659 31.7 95.5683 28.l 85.6446 31.8 95.8409 28.2 85.9232 31.9 96.1133 28.3 86.2016 32.0 96.3855 28.4 86.4799 32.l 96.6576 28.5 86.7580 32.2 96.9296 28.6 87.0359 32.3 97.2013 28.7 87.3137 32.4 97.4729 28.8 87.5912 32.5 97.7444 28.9 87.8687 32.6 98.0156 29.0 88.1459 32.7 98.2867 29.1 88.4230 32.8 98.5577 29.2 88.6999 32.9 98.8285 29.3 88.9766 33.0 99.0991 TABLE 5 Format for placing the millimole pH data on data cards. There must be exact correspondence in location on cards between the pH values in this table and the corresponding carbon dioxide values (table PHC) from the titration graph. 14.0 13.9 13.8 13.7 13.6 13.5 13.4 13.3 13.2 13.l 13.0 12.9 12.8 12.7 12.6 12.5 12.4 12.3 12.2 12.1 12.0 11.9 11.8 11.7 11.6 11.5 11.4 11.3 11.2 11.1 11.0 10.9 10.8 10.7 10.6 10.5 10.4 10.3 10.2 10.1 10.0 9.9 9.8 9.7 9.6 9.5 9.4 9.3 9.2 9.1 9.0 8.9 8.8 8.7 8.6 8.5 8.4 8.3 8.2 8.1 8.0 7.9 7.8 7.7 7.6 7.5 7.4 7.3 7.2 7.1 7.0 6.9 6.8 6.7 6.6 6.5 6.4 6.3 6.2 6.1 6.0 5.9 5.8 5.7 ture values are the same. This situation is usual where the barometer and tonometer are in the same room. If X is the initial carbon dioxide concentration in millimoles per ml in the sample, the total amount of carbon dioxide in the beaker in millimoles after each step of the titration may be indicated by the expression : Total C02= (V0 X +6 V M) (2) where V0 is the initial volume in the beaker ( 100, 200, or 300 ml) Changes in Carbon Dioxide Concentration From Changes in pH 6 Vis the total volume of titrant added up to that step in the titration in ml. Mis the quantity derived in equation (1) (mM C02/ml titrant). The final volume of fluid in the beaker at the end of any given step (V) is expressed by the relationship: V=V0 +6V (3) Dividing each side of equation (2) by V, an expression for the ~oncentration of total carbon dioxide [ C02T] in mM/ml may be obtained: [C02T]=V0 X+ 6VM (4) v The change in concentration of co, (6 [ CO'T]) from the beginning of the titration to the end of any given step is given by the equation: 6 [CQ,T] = [C02T] -X (5) Substituting equation ( 4) in equation ( 5) the expression becomes: 6 [C02T] = Vo X + 6 V M _ X (6) v Rearranging and factoring out, the expression becomes: 6[C02T] = X (V0 -V) + 6V M (7) v Substituting -6 V for V0 -V (from equation 3) the expression becomes: 6[C02T] =X (-6V) + 6VM (8) v Factoring out 6 V the expression becomes: 6[C02T] = 6V V (M-X) (9) The term F may be used to represent the dilution factor 6 V /V. Substituting Fin equa­tion 10 we derive the final expression : 6 [CO,T] = F (M -X) (10) Since X is small after sweeping the sample with a carbon dioxide-free gas, and since the whole titration involves a small volume change, FX is small and may be ignored. The "F" factors (times 1000 to correct to a liter basis) for the usual titration increments and sample volumes used are included as Table 4. Where FX is small: 6 [CQ,T] =FM (11) Raw data from a typical titration of sea water are shown in Table 2. When this titration was done, the observed barometric pressure was 765.2 mm Hg on a standard mercurial barometer with a brass scale. The temperature of the barometer and titrant was 24.4°C. Entering the M value table with 24.4°C and a barometric pressure of 765, (the uncor­ rected barometric pressure to the nearest mmHg) we find an M value of 0.03347. This is the concentration of carbon dioxide in millimoles dissolved in one ml of distilled wa­ ter under the true barometric pressure (partial pressure of the gas plus the aqueous ten­ sion at the stated temperature) and the observed temperature of the titrant. What is now desired is a curve showing the relationship between the pH of the sample and the amount of carbon dioxide dissolved in the sample. Data as to the volumes of titrant added from Column 2, Table 2 were used with Table 4 to obtain the F factors. The F factors were multiplied by the M value (Table 3) to obtain a relative value for carbon dioxide concentration at each pH. These data are shown in Column 3, Table 2 and Fig. 2. This method of calculation follows expression ( 11). For studies with better than D - VAN -SLY KE ( K.G. WOOD ) 9.0 0 1­•g •• ~=u~. • e - C02 -H20 TITRATION (FM l ·cu..•e:. 6 - COr H20 TITRATION F(M -X) tJO. •e:. .. ~!l. 0 ••• t •• 8.0 o ·er ~.o l • . pH !, o .o ;! • •• 0 7.0 I­ t! . · ·L!"~ .. t:I' ""lo • C; 0 C; 0 • 6.0 I­ I x+ o.o 0.5 1.0 1.5 2.0 RELATIVE 1.424 1. 924 2.424 2.924 3 .424 ACTUAL mM C02 / L FrG. 2. Typical graph produced by carbon dioxide-water titration of sea water (salinity 31.8%0 ). The quantity X represents the concentration of carbon dioxide in the sea water at the start of the titration. Van Slyke determinations of carbon dioxide concentration at several pH's on a duplicate sample are plotted for com­parison (Wood, 1963). Total carbon dioxide concentration by equation (10) and relative carbon dioxide concentration by equation (ll) , the abbreviated method, are plotted with separate scales on the abscissa. Changes in Carbon Dioxide Concentration From Changes in pH 5% accuracy, the initial carbon dioxide content (X) need not be determined. Where it is required, X may be determined with the Van Slyke method or with the infrared analyzer procedure of Wilson ( 1961). X may be approximated by the total alkalinity in high pH water if carbonate and bicarbonate are the only factors affecting the buffer system. Also given in Table 2 (Column 4) and plotted in Fig. 2 are the actual concentrations of carbon dioxide in the sea water based on the more accurate expression (10) and Dr. K. G. Wood's determination of X (0.001424 mM/ml at pH 8.93). The slope of the titration curve is directly influenced by the buffering capacity of the water. If a very hard water is used, the slope of the titration curve will be shallow, and if a very soft water is used, the slope will be much steeper. The same relationship holds true for the amount of time required to raise the pH of the water prior to titration. The harder the water, the greater the length of treatment with nitrogen or carbon dioxide free air necessary to raise the sample to a given pH. Diurnal Graph Computer Program pH-carbon dioxide graphs such as shown in Fig. 2 may be used with observed changes in pH taken from recorder charts to compute changes in carbon associated with me­tabolism and other processes of carbon dioxide exchange (Beyers, 1963a) . Where data are extensive, it may be convenient to make calculations with a computer program. Such a computer program for the Control Data Corporation 1604 Digital Computer was de­veloped to perform rapid calculation of respiration and production values from pH data by the methods presented earlier. Using hourly pH data, the machine interpolates from a pH-C02 titration graph the amount of C02 corresponding to that pH. The pH-C02 graph is made available for this computation by taking millimoles of C02 values for every 0.1 pH unit from the titration graph (covering the range of the diurnal pH's), placing them according to a prescribed format on data cards corresponding to the pH values given in Table 5, and feeding them, with a data identification number, pH data, light condition change times, a light sequence code number, and depth into the machine. With this information the program will compute the carbon dioxide values for each pH value, the increment of change between it and the next value, and, by integrating, calcu­late production and respiration values and their ratio. Further detail on format of data, order of data, etc, will be given below. The program description and a source deck of cards may be obtained by writing to the University of Texas Computation Center Pro­gram Library, Austin, Texas. M2 UTEX PRBYPH is the program name and should be given if a program request is made. A program print-out is given below, and references to format statement numbers will be made as the data list is described. Input data format is as follows: READ 99, NTRA 99 FORMAT (14) NTRA-an integer, the number of sets of pH-C02titration graph values to be read in. This number is right-adjusted in its field (Columns 1-4). READ 130, PHC 130 FORMAT (14F5.3) PHC-a table of 84 values of carbon dioxide taken from a pH-C02 titration graph which correspond to the pH values of Table 5. Changes in Carbon Dioxide Concentration From Changes in pH READ 99, NTRB 99 FORMAT (14) NTRB-an integer, the number of sets of pH data to be read in for each PHC table. This number is right-adjusted in its field (Columns 1-4). READ llO, NAME llO FORMAT (110) NAME-an integer number whereby the user must identfy each set of pH data. This number may contain up to 10 digits and occupies Columns 1-10. READ 100, PH 100 FORMAT (14F5.2) PH-a set of 25 pH values corresponding to pH readings taken every hour for a period of 24 hours. READ 140, KTIME, KCODE, DEPTH 140 FORMAT (315, F6.3) KTIME-two integer numbers which designate the times at which changes in light conditions occur (on to off or off to on). There are usually two such changes, and the numbers are derived by listing the pH data in a numbered Column ( 1, 2, 3, .. . , 25) . The number of the pH value at which the first change occurs is the first KTIME value and is right-adjusted in Columns 1-5. The number of the pH value at which the second change occurs is the second KTIME value and is right-adjusted in Columns 6-10. If only one light condition change occurs, the first KTIME value is 1, and the second number of the pH value at which the change occurs. KCODE-a control parameter, either 1 or 2 as determined by the sequence of light changes. The following table indicates which number is appropriate: Code Light condition sequence 1 off-on on--off--on 2 on-off ofI-on--off This number is placed in Column 15. DEPTH-a decimal number giving, in meters and to an increment limit of 1 milli­meter, the depth of the experimental location. This number is placed in Columns 16-21. The data are punched on cards in the order listed then placed with the source deck as prescribed by the particular monitor program on the computer used. Table 5 is gen­erated by the program and is used in interpolation. Two cautions should be made to the user. First, the program should be checked to in­sure compatibility between it and the computer on which it is run. Second, in the table PHC all 84 values must be represented whether by carbon dioxide values or by blank spaces. A computer program (M2 UTEX CARBON) which performs the same tasks as this one and plots the pH and rate of change values is available. Computation time per set of data is approximately 7 seconds as compared to less than one second per set of data with the above program. PROGRAM PRBYPH CALL LIMIT (20) 486 Changes in Carbon Dioxide Concentration From Changes in pH C CONVERSION OF PH TO CARBON ODIMENSION PHT(84) ,PHC (84) ,PH (25) ,KTIME (2) ,Cl2(25) ,DER (24) 99 FORMAT(l4) 100 FORMAT(l4F5.2) llO FORMAT (110) 111 FORMAT (15H IDENTIFICATION 4X,110) 120 FORMAT ( 15H PROGRAM PRBYPH / 21H BY NEALE. ARMSTROl\G) 130 FORMAT(l4F5.3) 200 FORMAT(lHl) PRINT 200 PRINT 120 PRINT 200 PHT(l)=l4.0 DO 170 I=l,83 170 PHT(I + 1=14.0-(0.l*FLOATF(I) ) READ 99,NTRA NCNB=O 129 READ 130,PHC READ 99,NTRB NCNT=O 131 READ llO,NAME READ 100,PH RSV(PHI=l). DO 201 I=l,25 PHI=PH(I) RSV (Wl=l,W2=1,W3=1). LDA (PHI) ,ENI2 (84), +THS2 (PHT) ,SLJ (201) ,LDA2(PHT) ,STAtWl), LDA2 (PHC) ,STA (W2) ,SIU2 ( 106), 106 ENI2(N) , INI2(1), LDA2 ( PHC) ,ST A (W3) . PHI=lO.O* ( (W3-W2) * (Wl-PH(I))) Cl2(l)=W2+PHI 201 CONTINUE DO 202 I=l,24 DER(I) =Cl2(1+l) -Cl2(I) 202 CONTINUE PRINT lll,NAME 132 FORMAT(// 3H PH lOX 7H CARBON 5X 17H CHANGE INCREMENT/) PRINT 132 133 FORMAT ( 1X,F6.3,9X,F6.3,6X,F6.3) PRINT 133, (PH(I) ,Cl2(I) ,DER(I) ,I=l,24) PRINT 133,PH (25) ,Cl2 (25) 140 FORMAT(3I5,F6.3) READ 140,KTIME,KCODE,DEPTH K=l AONE=O.O IF(KTIME(l) -1) 141,146,141 141 MM=2 KTM=KTIME(ll-1 138 ACA=DER(MM-1) 143 DO 142 I=MM,KTM ACA= ACA+DER (I) 142 CONTINUE GO TO ( 143,144,145) ,K 143 AONE=ACA 144 ATWO=ACA 145 ATHR=ACA+AONE 146 IF(K-2) 147,149,150 147 K=K+l MM=KTIME(l)+l KTM=KTIME(2)-l GO TO 138 149 K=K+l MM=KTIME ( 2) + 1 KTM=24 GO TO 138 150 ABA=ABSF( (ATWO*DEPTH) *44.0) ABB=ABSF( (ATHR*DEPTH) *44.0) IF(KTIME(l)-1) 151,152,151 151 KHB=KTIME(l)+(24-KTIME(2)) KHA=KTIME ( 2) -KTIME(1) GO TO 160 152 KHA=KTIME(2)-l KHB=24-KTIME (2) + 1 1600FORMAT(/11H PRODUCTION /1X,F6.3,2X,10H MM C02/L/ 12,4H HRS l/1X,F6.3,2X,12H GMS C02/M2/ 12,4H HRS) 1610FORMAT(/12H RESPIRATION /1X,F6.3,2X,10H MM C02/L/12,4H HRS l/1X,F6.3,2X,12H GMS C02/M2/12,4H HRS) GO TO (162,163),KCODE 162 KA=KHB ATHR=ABSF(ATHR) PRINT 160,ATHR,KA,ABB,KA KB=KHA PRINT 161,ATWO,KB,ABA,KB RATIO=ABB/ ABA GOTO 164 163 KA=KHA ATWO=ABSF(ATWO) PRINT 160,ATWO,KA,ABA,KA KB=KHB PRINT 161,ATHR, KB, ABB,KB RATIO=ABA/ABB 164 CONTINUE Changes in Carbon Dioxide Concentration From Changes in pH 165 FORMAT(/lOH P/R RATIO, 2X,F6.3) PRINT 165,RATIO 121 FORMAT (13H TIME CHANGES 2X,216/5H CODE 2X,14/6H DEPTH 2X,F6.3) PRINT 121,KTIME,KCODE,DEPTH PRINT 200 NCNT=NCNT+l IF(NCNT-NTRB) 131,167,167 167 NCNB=NCNB+ 1 IF (NCNB-NTRA) 129,166,166 166 CONTINUE END END Acknowledgments We would like to thank Dr. K. G. Wood for providing the sea water and the Van Slyke data; Mrs. Anne Wilkey and Mrs. Rita O'Donnell for aid in preparing the tables; and Mr. Bill Gillespie for the preparation of the figures. Literature Cited Atkins, W. R. G. 1922. The hydrogen ion concentration of sea water in its biological relations. J. Mar. biol. Assn. U. K. 12: 717-771. Atkins, W. R. G. 1923. The hydrogen ion concentration of sea water in its relation to photosynthetic changes. Part II. J. Mar. biol. Assn. U. K. 13: 93-118. Beyers, Robert J. 1962. Relationship between temperature and the metabolism of experimental eco­systems. Science 136: 980-982. Beyers, Robert J. 1963a. The metabolism of tweh-e aquatic laboratory microecosystems. Ecol. Monogr. 33: 281-306. Beyers, Robert J. 1963b. A characteristic diurnal metabolic pattern in balanced microcosms. Puhl. Inst. Mar. Sci. Univ. Tex. 9: 19-27. Beyers, Robert J., and Howard T. Odum. 1959. The use of carbon dioxide to construct pH curves for the measurement of productivity. Limnol. & Oceanogr. 4: 499-502. Beyers, Robert J., and Howard T. Odum. 1960. Differential titration with strong acids or bases vs. CO. water for productivity studies. Limnol. & Oceanogr. 5: 229-230. Black, William. 1961. Calcium carbonate saturation in ground water, from routine analyses. U. S. Geo!. Surv. Water-Supply Pap. 1535-D. 13 p. Bohr, C. 1899. Definition und Methode zur Bestimmung der lnvasions-und Evasions coefficienten bei der Auflosung von Gasen in Flussigkeiten. Ann. Phys. Chem., Leipzig 304(NF 68): 500-525. Brujewicz, 'S. W. 1930. Tagliche Schwankungen der hydrochemischen Faktoren im Flusswasser. Ver. int. Ver. Limnol. 5: 442-457. Delco, Exalton A., Jr., and Robert J. Beyers. 1963. Reduced metabolic rates in males of two cyprinid fishes. Copeia 1963 (l): 176-178. Hass, A. R. C. 1919. A method of studying respiration. J. gen .. Physiol. l: 17-22. Hepher, B. 1959. Chemical fluctuations of the water of fertilized and unfertilized fishponds in a sub­tropical climate. Bamidgeh 11: 71-80. Jackson, Daniel F., and W. A. Dence. 1958. Primary productivity in a dichothermic lake. Amer. Midi. Nat. 59: 511-517. Jackson, Daniel F., and James McFadden. 1954. Phytoplankton photosynthesis in Sanctuary Lake, Pymatuning Reservoir. Ecology 35: 1-4. Larimer, James L. 1961. Measurement of ventilation volume in decapod crustacea. Physiol. Zoo!. 34: 158-166. Lyman, John. 1961. Changes in pH and total C02 in natural waters. Limnol. & Oceanogr. 6: 80-82. Megard, Robert 0. 1961. The die! cycle of stratification and productivity in two lakes of the Chuska Mountains, New Mexico. Amer. Midi. Nat. 66: 111-127. McQuate, Arthur G. 1956. Photosynthesis and respiration of the phytoplankton in Sandusky Bay. Ecology 37: 834-839. Odum, Howard T. 1957a. Trophic structure and productivity of Silver Springs, Florida. Ecol. Monogr. 27: 55-112. Odum, Howard T. 1957b. Primary production measurements in eleven Florida springs and a marine turtle grass communnity. Limnol. & Oceanogr. 2: 85-97. Osterhout, W. J. V., and A. R. C. Hass. 1919. On the dynamics of photosynthesis. J. gen. Phsyiol. 1: 1-16. Park, K., Donald W. Hood, and Howard T. Odum. 1958. Diurnal pH variation in Texas bays, and its application to primary production estimation. Pub!. Inst. Mar. Sci. Univ. Tex. 5: 47--04. Revelle, Roger, and K. 0. Emery. 1957. Chemical erosion of beach rock and exposed reef rock. Geolog. Survey Professional Paper 260-T. U.S. Govt. Printing Office, Washington. Richman, Sumner. 1958. The transformation of energy by Daphnia pulex. Ecol. Monogr. 28: 273­ 291. Verduin, Jacob. 1951. Photosynthesis in naturally reared aquatic communities. Plant Physiol. 26: 45-49. Verduin, Jacob. 1956a. Energy fixation and utilization by natural communities in western Lake Erie. Ecology 37: 40-50. Verduin, Jacob. 1956b. Primary production in lakes. Limnol. & Oceanogr. 1: 85-91. Verduin, Jacob. 1957. Daytime rnriation in phytoplankton photosynthesis. Limnol. & Oceanogr. 2: 333-336. Verduin, Jacob. 1960. Phytoplankton communities of western Lake Erie and the C02 and O, changes associated with them. Limnol. &Oceanogr. 5: 372-380. Wells, R. C. 1922. Carbon dioxide content of sea water at Tortugas. Papers Dept. Mar. Biol., Car­negie Inst., Washington 18 : 89-93. Wilson, Ronald R. 1961. Measurement of organic carbon in sea water. Limnol. & Oceanogr. 6: 259­ 261. Wood, Kenneth G. 1963. Gasometric determinations of carbon dioxide in natural waters in relation to pH and the activity of plants. Proc. XV Int. Cong. Limnol. On press.) Wright, J. C. 1960. The limnology of Canyon Ferry Reservoir: III. Some observations on the density dependence of photosynthesis and its cause. Lim no!. & Oceanogr. 5: 356-361. Contributions From the Institute of Marine Science 1961-1962 Publications by staff, students, and visiting investigators. An asterisk (*) indicates co-authors associated with the Institute_ 1961 Kornicker, Louis S. Ecology and taxonomy of recent Bairdiinae (Ostracoda). Micropaleont. 7(1): 55-70. ----. Observations on the behavior of the littoral gastropod Terebra salleana. Ecology 42: 207. Oppenheimer, Carl H. Marine Microbiology. Naval Research Review, April 1%1, p. 11-14. ----. Note on the formation of spherical aragonitic bodies in the presence of bacteria from the Bahama Bank. Geochim. et cosmoch. Acta 23: 295-296. Oppenheimer, Carl H., Neil B. Travis, and Howe! W. Woodfin. Coliform distribution in Central Texas Bays. Water and Sewage Works, August 1961, p. 298-307. Price, W. Armstrong, and Louis S. Komicker.* Marine and lagoonal deposits in clay dunes, Gulf Coast, Texas. J. sediment. Petrol. 31: 245-320. Wilson, Ronald F_ Measurement of organic carbon in sea water. Limnol. &Oceanogr. 6(3) : 259-261. Wise, Charles D-Bathtub ecology for the biology class. Amer. Biol. Teacher 23(2): 108-109. 1962 Behrens, E. William. Environment reconstruction for a part of the Glen Rose Limestone, Central Texas. Ph.D. Thesis. Rice University, Houston. 166 p. Beyers, Robert J. The metabolism of twelve aquatic laboratory microecosystems. Ph. D. Thesis. University of Texas (Order No. 62-2544) 190 p. Univ. Microfilms, Ann Arbor, Mich. Beyers, Robert J. The relationship between temperature and the metabolism of experimental eco­systems. Science 136: 980-982. Briggs, John C. The clingfishes (Xenopterygii) of the Indo-Australian Archipelago, p. 444-453, I fig. In Vol. XI, Fishes of the Indo-Australian Archipelago. E. J. Brill, Leiden. Briggs, John C. Restoration of the frogfish, Antennatus retucularis (Gilbert). Copeia 1962 (2) : 440, 1 fig. ----. A new clingfish of the genus Lepadichthys from the New Hebrides. Copeia 1962 (2) : 424-425, 1 fig. ----. Results of the Amami Islands Expedition No. 5: The clingfishes (Gobiesocidae). Copeia 1962 (4): 851-852. ----.California fish families with suggested references for the identification of species. Stanford Natural History Museum Circular 9, 13 p. Golley, F., Howard T. Odum,* and R. F. Wilson.* The structure and metabolism of a Puerto Rican red mangrove forest in May. Ecology 43: 9-33. Hellier, Thomas R., Jr., and Louis S. Kornicker. Sedimentation from a hydraulic dredge in a bay. Puhl. Inst. Mar. Sci. Univ. Tex. 8: 212-215. Hellier, Thomas R., Jr. and H. D. Hoese. A note on the schooling behavior of the striped mullet (Mugil cephalus Linnaeus) in Texas. Copeia 1962 (2): 453-454. Hoskin, Charles M. Recent carbonate sedimentation on Alacran Reef, Yucatan, )fexico. Ph.D. Thesis. University of Texas. 254 p. Jones, Robert S. A new spawning area for lstiophorus albicans and the capture of two postlarval istiophorids from the Texas Coast. Copeia 1962(2): 453. Jones, Robert S.,* William F. Hettler, and Clark Hubbs. Effects of maternal death on survival of fertilized eggs of the fish Etheostoma spectabile. Tex. J. Sci. 14(3): 319-322. Komicker, Louis S. and D. W. Boyd. Bio-geology of a living coral reef complex on the Campeche Bank. Guide Book, Feld Trip to Peninsula of Yucatan, New Orleans Geological Society, 1962. Kornicker, Louis S. and D. W. Boyd. Shallow water geology and environments of Alacran Reef complex, Campeche Bank, Mexico. Bull. Amer. Ass. Petrol. Geol. 46(5): 640-673. Kornicker, Louis S. and Charles D. Wise. Sarsiella (Ostracoda) in Texas bays and lagoons. Crusta­ceana 4(1): 57-74. Lee, Byung Don and William N. McFarland. Osmotic and ionic concentrations in the mantis shrimp Squilla empusa Say. Pub!. Inst. Mar. Sci. Univ. Tex. 8: 126-142. R. R. Miller, and John C. Briggs.* Dactyloscopus amnis, a new stargazer from the rivers of the Pacifi; slope of southern Mexico. Occas. pap. Mich. Mus. 627: 1-11, 3 figs. Odum, Howard T. Man and the ecosystem. Proc. Lockwood Conference on the suburban forest and ecology. Bull. Conn. Agr. Exper. Station 652: 57-75. Odum, Howard T. The use of a network energy simulator to synthesize systems and develop anal­agous theory: the ecosystem example, p. 291-297. In Proc. Cullowhee conference on training in biomathematics. N.C. State College, Rahleigh, N. C. 390 P- Odum, Howard T., and Norman Vick. The paradox that film ecosystems are anaerobic basins, Ab­stract, p. 493. In Gorsline, D. S., Proceedings of the First National Coastal and Shallow Water Research Conference, Tallahassee, Fla. 897 p. Odum, Howard T., and R. Wilson. Further studies on the reaeration and metabolism of Texas Bays. Puhl. Inst. Mar. Sci. Univ. Tex. 8: 23-55. Oppenheimer, Carl H., and Roiger Jannasch. Some bacterial populations in turbid and clear sea water near Port Aransas, Texas. Puhl. Inst. Mar. Sci. Univ. Tex. 8: 56--60. Parker, Patrick L. Zinc in a Texas Bay. Puhl. Inst. Mar. Sci. Univ. Tex. 8: 75-79_ Rice, Winnie H., and Louis S. Komicker. Mollusks of Alacran Reef, Campeche Bank, Mexico. Puhl. Inst. ~Iar. Sci. Univ. Tex. 8: 366-403. Volkmann, Carol M., and Carl H. Oppenheimer. The microbial decomposition of organic carbon in surface sediments of marine bays of the central Texas Gulf Coast. Puhl. Inst. Mar. Sci. Univ. Tex. 8: 80-96. Wright, Thomas, and Louis S. Kornicker. Island transport of marine shells by birds on Perez Island, Alacran Reef, Campeche Bank, '.\fexico. J. Geo!. 70(5): 616-618.