Bulletin, Southern California Academy of Sciences Volume 54 ...._.. Part 1, 1955 RECORDS OF SOME PLIOCENE AND PLEISTOCENE REPTILES AND AMPHIBIANS FROM MEXICO By Bayard H. Brattstrom* A considerable number of fossil vertebrates from Pliocene and Pleistocene localities in Mexico have accumulated in the collec-tions of the California Institute of Technology. A few of the fossil species from these deposits have been described, but the bulk of the material is still unexamined. In addition to the lizards from the San Josecito Cavern deposits already discussed (Brattstrom, 1955b ) , reptiles and amphibians have been found in this Mexican material from three major areas. These are: The Pliocene Yepo-mera formation of Chihuahua, the Pliocene Goleta formation of Michoacan, and the Pleistocene deposits of Zumpango, Mexico, Mexico. Though most of the material is quite fragmentary and can only be identified to genus, the identifiable material is of considerable interest as our knowledge of late Cenozoic zoo-geography of Mexico is little known and any information is useful. YEPOMERA FORMATION, CHIHUAHUA Fossil vertebrates have been obtained by the California Insti-tute of Technology from continental deposits exposed in the drainage basin of the Rio Papigochic in western Chihuahua, Mex-ico. Quarries in fossiliferous outcrops have been opened in the vicinity of Matachic, Yepomera, and to the north of Yepomera in the general area called Rincon. The relative ages of the various quarry sites have not been determined in detail, but the faunas are of Hemphillian age. The described mammals from the Yepo-mera or Rincon area include a rabbit, Notolagns velox (Wilson, 1937); a badger, Taxidea mexicana (Drescher, 1939); an anti-locarprid, Hexobelotnerix fricki ( Furlong, 1941 ) ; a marmot, Mar-mota mexicana and two ground squirrels, Citellus pattersoni and C. matachicensis (Wilson, 1949); a bear, Hyaenarctos schneideri (Stock, 1950); and the horses Pliohipous (A.) stockii, P. (P.) mexicanus, Nannipus cf. minor, and Neohipparion cf. phosphor-um (Lance, 1950). The only herpetological material thus far found in these deposits is a toad which is described here as new: ♦Contribution No. 718, Division of Geological Sciences, California Institute of Technology, Pasadena 4, California.
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