74 The Mammals of Colorado 
than in longipes, and quite heavily lined with black; tail stripes 
dark, rather blackish, and continuous to pencil, but Merriam states 
that the lower stripe is often absent beyond end of vertebrae. 
Under parts white. Post-auricular spot large. 
Distribution. — The Mountain Kangaroo Rat has been recorded 
from Colorado only, and in this State the only record is at present 
Costilla County, and the extreme southern part of Saguache 
County, but it is no doubt the species inhabiting that portion 
of the San Luis Valley suitable for these animals. It attains an 
elevation of nearly 8,000 feet at Fort Garland and Crestone. 
Habits. — The different species of Kangaroo Rats all have 
very similar habits, and the following description will serve 
for them all. They are burrowing animals, and are of social 
habits to a certain extent, being usually found in colonies 
FIG. 28. MOUNTAIN KANGAROO RAT, PcrodtpUS mOfltanuS 
E. R. Warren, Photo. 
of varying numbers. These burrows are of considerable 
length, one opened by Frank Stephens in California having 
a total length of fourteen feet, and besides this main tunnel 
there were several short side branches, each terminating in 
a chamber, which was used either as a storeroom, or as a 
