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U. S. P. R. R. EXP. AND SURVEYS ZOOLOGY GENERAL REPORT. 



crowded, not very strongly marked, subqnadrate blotches, separated by black and yellowish 

 brown ; towards the nape this mottling blends into a more uniform grayish, and a similar con 

 dition is seen on the sides, where obsolete black forms a faint mottling. The under parts are 

 of a rusty yellowish white, deepest between the fore legs, on the sides of the head and neck, the 

 axillte. The throat and chin and the genital regions are dirty white. The top of the head is 

 a chestnut brown, paler towards the occiput. There is a ring round the eye of a lighter color 

 than the rest of the face. 



The upper part of the tail is a mixed black and yellowish gray, the margin all round a pale 

 brownish white or yellowish ; there is a broad subterminal bar of black, about one-third as 

 long as the caudal vertebrae. The under surface of the tail, within the light-colored margin, 

 is a uniform light chestnut, the subterminal black showing through. The hairs beneath the 

 tail show no annulation whatever, except near the tip, where they are mostly black, but with 

 chestnut base and pale tip. Above, the caudal hairs are annulated black and grayish yellow. 



The under fur is quite full and soft, even in the summer specimens ; everywhere sooty black 

 at the base, then abruptly of a grayish yellow, passing into pale rusty, this latter color deepest 

 on the back, becoming paler on the sides and beneath. Orj the back and sides numerous long 

 stiff hairs are interspersed, either entirely black, or else with a subterminal grayish white or 

 rusty white annulus, the extreme tip generally black. The mottling of the back is chiefly due 

 to this annulation. 



This species is quite closely allied to the Spermophilus eversmannii of Siberia, (Nos. 1455, 19GT,) 

 but is readily distinguished by larger size, shorter and more bushy tail. The top of the head 

 is much more rusty, the subterminal black bar of the tail much broader. For the sake of com 

 parison I give the measurements of two Siberian specimens of S. eversmannii. 



Although it is by no means certain that this animal is identical with Spermophilus parryi, 

 yet there appears to be no reasonable doubt on the subject. There is nothing to prevent the 

 mammalia of the northwestern portions of this continent from passing over to Asia, as the strait 

 intervening is frozen solid every winter. Brandt, and the Russian zoologists generally, give 

 the Siberian and American species as identical. 



Measurements. 



