This catalog lists documents from the Archivo General de la Nación, Mexico City, selected by Elinor G. K. Melville during her research to produce A Plague of Sheep: Environmental Consequences of the Conquest of Mexico (1994). The documents were selected from various ramos of the AGN. The 18 reels in this catalog correspond to her original numbering of reels 1-15 and 18-20 of the documents. Her originally numbered reels 16 and 17 have been separately cataloged to provide better access to two whole volumes (2346 and 2627) from the Ramo de Tierras which they contain; see Benson Latin American Collection FILM 26437 for a description of these two reels.