MAMMALS OF UTAH 51 



the subterminal portion being grayish white ; the basal and 

 terminal black. The basal fur above is black, laterally it 

 is of a bluish ash. On the posterior half of the body the 

 white is replaced by pale yellowish brown, and the black by 

 a dark brown. On the sides the colors are purer, the hairs 

 becoming lighter at the base in passing down the sides and 

 to the root of the tail. The under parts are of a pale ful- 

 vous white, changing into pale brownish yellow anteriorly, 

 posteriorly, and on the inner faces of the limbs, the hairs 

 being everywhere brown at the base, except on the last men- 

 tioned region. The top and sides of the head are grayish 

 white and black, mixed, the latter predominating. The eye- 

 lids are white; the exterior surface of the ear is brownish 

 yellow, as is the posterior border of the inner surface; the 

 remainder is dark brown. The tail is white and black, the 

 former predominating and constituting rather a broad border 

 all round ; there are three distinct rings of black, the outer 

 and sub-terminal one broadest. In some specimens the 

 white appears more or less soiled. Body about 12 inches; 

 tail with hairs 9; hind feet 2.25. (Baird.) 



Distribution — The type locality of this species is Pur- 

 gatory river, Las Animas, Colorado. It extends into Utah 

 along the Grand River. Specimens have been taken from 

 the Book-Cliff mountain region. 



Habits — Rock squirrels nearly always live in rocky 

 situations, such as the ledges and boulder-strewn sides of 

 canyons, the bare rocky slopes along the base of the foot- 

 hills, and the rim rock of outlying mesas and buttes being 

 especially frequented. Rock squirrels are quite shy and 

 wary, and when one is surprised in the bottom of a canyon, 

 as is often the case, it invariably runs up the slope and 

 takes refuge among the rocks above. If the observer re- 

 mains perfectly quiet, he may at length detect the animal 

 peering silently over the top of a large boulder, but it gen- 

 erally vanishes at the slightest noise or motion. I watched 

 one of these squirrels dusting itself near Bayfield. Ap- 

 parently it was unaware of my presence and at intervals 

 would run to a dusty spot in a path, throw the dust up with 

 its fore feet, turn on its back, and wriggle and squirm along 

 the ground in the greatest enjoyment. This performance 

 was repeated a number of times, when suddenly the little 

 fellow spied me and raced off through the brush. The food 

 of rock squirrels consists chiefly of pinyon nuts, acorns, and 

 juniper berries, and consequently over much of their range 

 the animals do little damage. (Gary.) 



