(USBS). _Johnson County_:
6-1/2 mi. W, 2 mi. S Buffalo, 5620 ft., 4 (KU); 1 mi. WSW Kaycee,
4700 ft., 1 (KU). _Natrona County_: Casper, 1 (USBS); 1 mi. NE
Casper, 5150 ft., 1 (KU). _Platte County_: 2-1/2 mi. S Chugwater, 1
(KU). _Sheridan County_: Arvada, 2 (USBS); 5 mi. NE Clearmont, 3900
ft., 1 (KU). _Weston County_: Newcastle, 1 (USBS); 23 mi. SW
Newcastle, 4500 ft., 4 (KU).

=Perognathus fasciatus infraluteus= Thomas

_Perognathus infraluteus_ Thomas, Ann. Mag. Nat. Hist., ser. 6,
11:406, May, 1893, type from Loveland, Larimer County,
Colorado.

_Perognathus fasciatus infraluteus_, Osgood, N. Amer. Fauna, 18:19,
September 20, 1900.

_Geographic distribution._--Known only from the type locality and
from 7 mi. N Ramah, Colorado. Probably in other parts of
northeastern Colorado (see Figure 1).

_Remarks._--For comparisons with _Perognathus fasciatus olivaceogriseus_
Swenk, geographically adjacent to the north, see the preceding account
of that subspecies on page 520.

Of the seven topotypes available to me, six show various degrees of
encroachment of the color of the lateral line upon the underparts,
giving the ventral surface a buffy appearance, the "distinguishing
character" of the subspecies according to Osgood (_op. cit._:20). When
additional specimens are available, this character may be found to be
one of individual variation, although no specimens from other parts of
the range of the species have been found to exhibit it. Of the
subspecies _P. f. infraluteus_, each of the eight specimens examined by
me possesses buffy subauricular patches.

The specimen from 7 mi. N Ramah, Colorado, is slightly darker and less
drab than the topotypes and does not possess buffy underparts. The skull
of the specimen is broken but on the basis of characters of the pelage
it seems to be intermediate between _infraluteus_ and _olivaceogriseus_
and is referred to the former on geographic grounds.

_Specimens examined._--Total number, 8, as follows: COLORADO:
_Elbert County_: 7 mi. N Ramah, 1 (MZ). _Larimer County_: Loveland,
7 (USBS).

=Perognathus fasciatus litus= Cary

_Perognathus fasciatus litus_ Cary, Proc. Biol. Soc. Wash., 24:61,
March 22, 1911, type from Sun, Sweetwater Valley, Natrona
County, Wyoming.

_Geographic distribution._--Lower Sweetwater Valley and adjacent
parts of Red