272 TJ. S. P. R. R. EXP. AND SURVEYS ZOOLOGY GENERAL REPORT. 



SCIURUS FREMONTII, Towns. 



Small Mountain Gray Squirrel. 



Sdunts fremontii, ("Townsend,") ATJD. & BACH. N. Ain. Quad. Ill, 1853, 237 ; pi. cvlix, fig. 1. 



About the size of the Hudson's Bay squirrel, S. hudsonius. Tail shorter than the body. Ears tufted in winter, but not 

 in summer. Above mixed brown, gray, and pale rusty, the prevalent tint similar to that of the gray squirrel ; beneath 

 bluish white ; a dark line along the sides. Eyelids white. Tail entirely black at end, the hairs tipped with light gray ; 

 on other parts of the tail a mixture of plumbeous and grayish rusty at the base of the hairs. No rusty visible externally. 



The general appearance of this animal is that of the chickaree or red squirrel, (Sciurus 

 hudsonlus,') which it resembles in size. The whiskers are moderate in length, not reaching 

 much beyond the ears. The ears are large, the exposed portion of the concavity densely coated 

 with hair ; the inner or convex surface still more, but with no appearance of tufts in summer 

 whatever not nearly so much as in S. hudsonius. In the winter specimen described by Audubon 

 and Bachman, however, the ears are very strongly tufted. 



On the fore foot the first finger or thumb is rudimentary, being a mere tubercle, without any 

 claw ; the second, third, and fourth increase successively ; the fourth is longest (the claw of the 

 second not reaching to the base of its claws ;) the fifth, or outer, is barely shorter than the 

 second. The palm is naked. On the hind feet, the first toe is a little shorter than the fifth ; 

 the second, third, and fourth nearly equal. The sole is naked from the tarsus ; probably hairy 

 in winter. 



The tail is of moderate length ; flattened, not bushy, and rather shorter than the body. 



The whole upper parts and sides are finely mottled by the narrow annulation of the hairs 

 with gray, black, and light reddish brown, none of these colors predominating, though the 

 general tint is faintly darker along the back. About the head there is an additional shade of 

 dark bluish ash. Eyelids white ; sides of the snout rusty white ; whole under parts clear bluish 

 white. The exterior surfaces of the limbs are pale rusty. The separation of the colors of the 

 belly and sides, between the fore and hind limbs, is clearly marked by a dark line about one- 

 fourth of an inch wide. The hairs on the body are all lead color for about half their length ; 

 those above are narrowly annulated besides with pale rusty and black, with light tips. 



The hairs on the end of the tail are entirely of a glossy black, except a light tip of grayish ; 

 towards the root of the tail they become more plumbeous at tho base, then pale rusty brown, 

 black and grayish white. 



This species appears to differ from most of the small true squirrels in the nearly black and 

 white tail, the tip being black. 



The specimen described by Audubon :s in winter dress, with long ear tufts ; the present is in 

 summer. 



There are few well defined species of North American squirrels of which we know so little as the 

 subject of the present article. The specimen described by Audubon and Bachman was collected 

 in 1849 by Colonel Fremont somewhere in the vicinity of the South Pass, and is now in the 

 Museum of the Philadelphia Academy of Natural Sciences. The one brought home by Captain 

 Beckwith was found in the Sawatch Pass, and the two are all that as yet have come to the 

 notice of naturalists. 



