approximately equal in length, occasionally plates reduced in length and rarely one or both plates are lost with wear in old individuals; patch of whitish or buffy hairs surrounding nose of most individuals. The primitive character of the lower dentition, as described in the species account above, suggest that _Cratogeomys_ [= _Pappogeomys_] _bensoni_ Gidley should be referred to the subgenus _Pappogeomys_ rather than _Cratogeomys_. Only the upper dentition would make positive identification possible; however, reference to the subgenus _Pappogeomys_ seems to be the best arrangement at this time. _Referred species._--Three (one extinct): *_Pappogeomys bensoni_ (Gidley), 1922. U. S. Geol. Surv. Prof. Papers, 131:123. Type from Benson local fauna (late Pliocene), Cochise County, Arizona. _Pappogeomys alcorni_ Russell, 1957. Univ. Kansas Publ. Mus. Nat. Hist., 9(11):359. Type from 4 mi. W Mazamitla, Jalisco. _Pappogeomys bulleri_ Thomas, 1892. Ann. Mag. Nat. Hist., Ser. 6, vol. 10:196, August. Type from "near Talpa," west slope of Sierra Madre de Mascota, Jalisco. Subgenus =Cratogeomys= Merriam 1895. _Cratogeomys_ Merriam, N. Amer. Fauna, 8:150, January 31. 1895. _Platygeomys_ Merriam, N. Amer. Fauna, 8:162, January 31. Type: _Geomys gymnurus_ Merriam, 1892. _Type._--_Geomys merriami_ Thomas, 1893, from "Southern México," probably in Valley of México. _Chronologic range._--Late Pleistocene, from Wisconsin deposits (San Josecito Cave, Nuevo León, Upper Bercerra, México, and Burnet Cave, New Mexico, local faunas) to the Recent.