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 deg. 30' and 39 deg. 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_.