The Pocket Gopher Family 
77 
Perodipus longipes (Lat. longus, long, +pes, foot, 
long-footed) . 
Dipodops longipes Merriam, N . A. Fauna, No. 3, p. 72 (1890). 
Type locality. — Echo Cliffs, Painted Desert, Coconino County, 
Arizona. 
Measurements. — Total length, 10.8; tail vert., 6.5 ; hind foot, 1.65. 
Description. — (From a specimen taken in western Montezuma Co. 
April 12): Above bright ochraceous buff, finely but rather sparsely 
interlined with black-tipped hairs. Upper and lower tail stripes 
dusky, continuous with pencil. Under parts pure white. Specimens 
of Kangaroo Rats taken at Coventry and Bedrock, southwestern 
Montrose County, while different in color from the typical animal, 
are not regarded b'*'' Dr. Merriam as sufficiently so for separation. 
Instead of being a bright, clear buff, they are dusky, and more or 
less lined with black. It is a similar color phase to that mentioned 
in the cases of the Golden Pocket Gopher and Apache Pocket Mouse 
from the same locality. 
Distribution. — The Moki Kangaroo Rat inhabits Arizona, New 
Mexico, southeastern Utah, and southwestern Colorado. In Colo- 
rado it has been taken in the western parts of Montezuma, Montrose, 
and Mesa counties. At Coventry, Montrose County, it reaches an 
elevation of 6,800 feet. 
Family GEOMYIDiE 
Rodents of fossorial habits with stout thickset bodies, 
short stout limbs, short tails, and small eyes and ears, and 
provided with large fur-lined cheek pouches opening on 
either side the blunt head outside the mouth; skull with strong 
flaring zygomata; dentition, i., i; c, -g-; pm., \) m., f X2 =20; 
incisors broad; molars rootless, with transverse laminae. 
This family is confined to North America, south to Panama. 
Key of the Genera 
A. Upper incisors without grooves, quite smooth. Thomomys, 
P- 77- 
B. Upper incisors with two longitudinal grooves. Geomys, 
p. 85. 
C. Upper incisors with one longitudinal groove. CratogeomySj 
p. 89. 
Genus THOMOMYS (Grk. thomos, a heap, -t- miis, mouse, in 
allusion to the mounds thrown up by the animal). 
