The first published reference that we have found to pocket gophers of Kansas is Prof. Spencer F. Baird's (1857:377, 380) mention of two specimens from Fort Riley. One he identified as Geomys bursarius (p. 377) and the other (p. 380) he doubtfully referred to Geomys breviceps. Both specimens were obtained by Dr. W. A. Hammond. J. A. Allen (1874:49) reported pocket gophers from Kansas under the generic name "Geomys?". Professor M. V. B. Knox (1875:21) published a list of Kansas mammals in which he used the names Geomys bursarius Shaw and Geomys breviceps Baird, the last one for the specimen taken by Dr. Hammond, at Fort Riley. Baker (1889:57) employed the name Geomys bursarius Rich. for the gopher "found along the hundredth meridian, between N latitude 38° 30' and 39° 30'." He reported this animal as common in western Kansas. Merriam (1895:129) recorded G. bursarius and G. lutescens from Kansas. Allen (1895:265) recorded five specimens of Geomys lutescens collected between September 16 and October 13 at Long Island, Phillips County, Kansas, by W. W. Granger. Since that time several papers, some of them dealing mostly with habits of pocket gophers, have been published in which reference is made to Geomys in Kansas. Hibbard (1933:240) recognized three species: G. bursarius, G. lutescens, and G. breviceps llanensis. In 1944 (74-75) he recorded Cratogeomys from Meade County, on the basis of two skulls dug out of the ground, and he recognized the same three full species of the genus Geomys that he did in 1933, along with two additional subspecies.

Specimens to the total number of 335 from Kansas have been available for the present study of the five subspecies recognized. The reason for arranging all of the named kinds as subspecies of a single species is that intergradation has been found to occur between every pair of kinds having contiguous geographic ranges. The characters previously thought by some writers constantly to differentiate, say, Geomys lutescens of western Kansas from Geomys bursarius of eastern Kansas, prove not to do so; instead, in areas geographically intermediate between the geographic ranges of the two kinds, the pocket gophers are intermediate in morphological characters and therefore are regarded as intergrades. Intergradation of this kind here is accepted as the criterion of subspecies, and lack of such intergradation as the criterion of species. Search for structural characters, distinctive of the different kinds, additional to those characters noted by other writers, has resulted in the finding of a few such characters but they too are subject to intergradation. Therefore the several kinds are arranged as subspecies of a single species which takes the name Geomys bursarius because it is the oldest available name. Detailed comment on specimens showing intergradation are to be found in the accounts of G. b. bursarius and G. b. major.