e
for assignment of the specimens from Meade County (and elsewhere in
southwestern Kansas) to _dychei_, they are, everything considered,
nearer _aztecus_, to which subspecies they have been assigned
consistently since first reported from the area by Hill and Hibbard
(1943:24).

Of two specimens examined from 10 mi. S and 1 mi. W Gruver, Hansford
Co., in the Panhandle of Texas, the one adult is clearly assignable to
_aztecus_ as is the specimen from 9 mi. E Stinnett, Hutchinson Co.,
Texas, that was referred to _dychei_ by Blair (1954:249).

_Reithrodontomys megalotis aztecus_ has had a rather unstable taxonomic
history. Allen, who originally named the subspecies (1893:79), regarded
it two years later (1895:125) as a synonym of _R. m. megalotis_, the
subspecies with geographic range to the south and west of that occupied
by _aztecus_. Howell (1914:30) recognized _aztecus_ as valid, but he,
too, questioned its distinctness from _megalotis_ in a later paper
(1935:144). Hooper (1952:218), the most recent reviewer, supported the
validity of _aztecus_ because specimens available to him averaged
"distinctly larger in skull length and size of brain case" than
specimens of _megalotis_. Our comparisons of typical specimens of
_aztecus_ with specimens of _megalotis_ from southern New Mexico and
southwestern Texas confirm Hooper's observations and indicate also that
_aztecus_ has a longer rostrum and slightly longer ear.

_Specimens examined._--205, as follows:

COLORADO. _Alamosa County_: Medano Ranch, 15 mi. NE Mosca, 16
(USNM). _La Plata County_: 1 mi. NW Florida, 6700 ft., 1; Florida,
6800 ft., 1. _Las Animas County_: 1 mi. S, 7 mi. E Trinidad, 2.
_Montezuma County_: 1 mi. W Mancos, 5; north end, Mesa Verde Nat'l
Park, 7000 ft., 3; Far View Ruins, Mesa Verde Nat'l Park, 7700 ft.,
3; Park Point, Mesa Verde Nat'l Park, 8525 ft., 2; within 3 mi. Rock
Springs, Mesa Verde Nat'l Park, 7500-8200 ft., 6. _Prowers County_:
Lamar, 2. _Rio Grande County_: Del Norte, 1 (USNM).

KANSAS. _Finney County_: 1 mi. S, 2 mi. E Garden City, 4. _Ford
County_: 1/2 mi. NW Bellefont, 10; 6-1/4 mi. N Fowler, 2. _Grant
County_: 2 mi. S, 9 mi. W Santanta, 1. _Kearney County_: 3-1/2 mi.
N, 4 mi. E Lakin, 4. _Meade County_: within 2-1/2 mi. Fowler, 10;
Meade County State Park, 14 mi. SW Meade, 48; 17 mi. SW Meade, 5.
_Morton County_: 7-1/2 mi. S Richfield, 4; 8 mi. N Elkhart, 1; 7-1/2
mi