Neocomian faunas were first recognized in Mexico by Carlos Burckhardt (1906, p. 183–191; 1912, p. 172–195, pl. 41–46) at the beginning of the present century and were briefly described in two monographs dealing principally with Jurassic faunas. The most important contribution to the systematic paleontology of Neocomian faunas of Mexico was made by Emil Böse (1923a, p. 19–29, 69–118), who recognized several subdivisions of the Neocomian. In subsequent papers (1923b, p. 209–211, 331; Böse and Cavins, 1927, p. 17–19, 57–58, 81) he discussed the stratigraphy and distribution of the Neocomian strata. A summary of all work done on the Neocomian of Mexico is included by Burckhardt (1930) in his last monumental work.
In studying the geology of the Sierra de Parras of southern Coahuila in 1934 and 1935, the writer recognized the Taraises formation as a distinct limestone formation lying between . . .