Several specimens of the subgenus _Cratogeomys_ have been reported from beds of latest Wisconsin (certainly after the glacial maximum) or post-Wisconsin age. Gilmore (1947:158) found fossil remains of _Cratogeomys_ [= _Pappogeomys_] _castanops_ commonly in Quaternary cave deposits on the mountain slopes in the vicinity of Cuatro Ciénegas, in central Coahuila. These deposits actually may be of post-Wisconsin origin (see discussion above). Alvarez (1964:8) obtained fragments of _Cratogeomys_ [= _Pappogeomys_] _tylorhinus_ from sub-Recent deposits of Capa III in the Cueva La Nopalera in southwestern Hidalgo, México. _Pappogeomys merriami_ lives in the area today. Mayer-Oakes (1959:373) reported remains of _Cratogeomys_ [= _Pappogeomys_] _merriami_ from levels eight and eleven of the excavations at El Risco II, in the northern part of Mexico City. The ages of these deposits are unknown to me, but they probably are no older than late Wisconsin with most of the beds dating from the post-Wisconsin. _Orthogeomys_ This genus is not known from the Pleistocene, except for its occurrence in the San Josecito cave deposits of southwestern Nuevo León, México (Russell, 1960:544). Although _Orthogeomys_ does not occur in the immediate vicinity of the cave at the present time, the northern limits of its range is nearby in southern Tamaulipas. The _Orthogeomys_ from San Josecito Cave differs from living species, and has been named _Heterogeomys_ [= _Orthogeomys_] _onerosus_ Russell (_loc. cit._), and is evidently referable to the subgenus _Heterogeomys_. As mentioned before, the San Josecito Cave local fauna represents deposits of Wisconsin glaciation. HISTORY OF CLASSIFICATION The account of the Tucan or Indian mole by Hernandez (sometimes listed as Fernandez) in 1651 probably is the earliest published one of a geomyid (see Merriam, 1895:201; Coues, 1877:607-608). Linnaeus in 1758 did not mention geomyids. In 1772, Kerr described Hernandez's Tucan under the name _Sorex mexicana_ on the basis of Hernandez's account without having seen any specimens. Lichtenstein in 1827 applied the technical name _Ascomys mexicana_ to three specimens collected by Deppe from unknown localities on the tableland of México. Merriam (_loc. cit._) pointed out that the name _mexicanus_ of Lichtenstein in 1827 is a _nomen nudum_, and that it is preoccupied by _mexicanus_ used by Kerr in 1792. The latter can not be technically identified with any particular species of geomyid.