620 
U S. P. R. R EXP. AND SURVEYS—ZOOLOGY'-GENERAL REPORT. 
The general appearance of the animal as to color is that of a young rabbit. The upper parts 
and sides are light yellowish brown, relieved by dusky points to the hairs, especially on the back 
and loins, and passing on the rump into a grayish tinge. The region around the anus, the feet, 
and the under parts generally, are dull yellow brownish, or pale rufous white. The silky hairs 
on the back of the ear are the color of dirty cotton ; anteriorly, more dusky. The ears are 
narrowly margined with white. The hairs of the hack are lead colored for their basal two- 
thirds. 
The estimated length of the animal is 8 inches. Hind foot from heel 1 T V inches. The ear 
is about an inch high. Collected in the South Pass by Townsend. 
Mr. Townsend, in his adventurous journey across the continent to the mouth of the Columbia, 
obtained the single specimen just described, and, as far as I know, the only one ever taken 
within our limits. They are met with in “ about latitude 42°, high up on the alpine region of 
the ridges dividing the waters of the Columbia, Colorado, and Missouri, (in the South Pass of 
the Eocky Mountains,) hiding among loose piles of rocks or stones, such as are generally seen 
beneath broken cliffs. They uttered a slender but distinct bleat, much like that of a young 
goat.” 
According to Richardson, this species inhabits the Eocky Mountains as far north as 60° 4' 
north latitude. It is not known whether, like the other pikas, the “ little chief” lays up a store 
of winter provisions, although this is quite probable. 
