Remains of _Nerterogeomys_ [=_Zygogeomys_] have been found in the Benson local fauna, Cochise County, Arizona, and the Rexroad local fauna of Kansas. This early Blancan gopher first was described as _Geomys minor_ by Gidley (1922:123), and was later referred by Gazin (1942:487) to his new genus _Nerterogeomys_. Hibbard (1950:138) identified specimens from the Fox Canyon locality, one of the localities of Meade County, Kansas, where the Rexroad local fauna is preserved, as _Nerterogeomys_, and tentatively referred them to the species _N. minor_. _Nerterogeomys_ cf. _minor_ has been recovered also from Locality 3 of the Rexroad local fauna (Hibbard, 1950:171) of Meade County, Kansas. Apparently these are also the small gophers about which Franzen (1947:58) wrote. She assigned them to the genus _Geomys_, and they may actually be a primitive form of _Geomys_ that represents an intermediate stage in the development of the enamel pattern from the uninterrupted loops of the ancestor to the discontinuous pattern of modern _Geomys_. I favor this interpretation; the evidence, however, is inconclusive, and I have, therefore, reluctantly allocated them, along with the other specimens of _Nerterogeomys_, to the genus _Zygogeomys_. In an early paper, Hibbard (1938:244) erroneously referred the same specimens, two upper premolars of a young individual, to the genus _Thomomys_, and the same material was identified with the genus _Geomys_, also without specific assignment, in a later paper (Hibbard, 1941b:278). _Thomomys_ is unknown from the late Pliocene of the Great Plains. The specimens previously referred to _Nerterogeomys_ are assigned to the genus _Zygogeomys_ for the first time in this report; for a discussion of the systematic arrangement see the accounts beyond. The type and paratype of _Nerterogeomys_ from the Benson local fauna of Arizona have no indication of enamel reduction.