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



"Size of the cat squirrel, (Sciurus cinereus;) fur rather coarse; body mottled with black and 

 ashy white, forming irregular narrow transverse bars on the back and sides ; tail as long as 

 the body, (exclusive of head?) and moderately bushy. Top of head pure black ; muzzle rufous 

 brown above, whitish on the sides. Back of the ears blackish brown. Hairs of the tail long, 

 (some of them two inches ;) brownish white, annulated by three broad black rings, the sub- 

 terminal one broadest. Length to root of tail, 13 inches ; of tail vertebras, 7f inches ; of tail, 

 with hairs, 10 inches ; height of ear, half an inch ; hind foot, 2^ inches." (Aud. and Bach.) 



This species was described by Bennett from a specimen collected in western Mexico, and has 

 not yet been fairly established as an inhabitant of the United States. It has a very close 

 resemblance to S. grammurus, and may possibly prove the same, though I have seen none of 

 this last mentioned species with the black crown, nor is any mention made by Bennett or 

 Audubon and Bachman of the purer gray of the anterior part of the body. I have already 

 suggested the possibility that the specimen from Los Nogales (No. 1046) may be different from 

 S. grammurus, and belong to this species, but, as its colors have been altered by immersion in 

 alcohol, it is impossible now to decide. 



? SPEBMOPHILUS CLARKII. Western America. 



This supposed species has already been discussed under the head of Sciurus clarkii, page 279. 

 Its reference, by some authors, to the genus Spermophilus rather than to Sciurus, is scarcely 

 warranted by the vague description of Hamilton Smith. 



