RODENTIA SCIURINAE SPERMOPHILUS COUCHII. 



311 



color. This specimen was probably collected in the South Pass, however, as there is no evidence 

 of the existence of the species west of the Rocky Mountains, and it is well known that Town- 

 send's specimens were not all labelled with critical accuracy. 



The species was first described by Say, in Long's Narrative, from a specimen taken in July 

 on Purgatory Creek, a tributary of the Arkansas, near Bent's Fort, about latitude 3*7 32', longi 

 tude 103 30'. It has not been since known until its re-discovery by recent government expedi 

 tions, for which reason no mention is made of it by Audubon & Bachman. 



List of specimens. 



SPERMOPHILUS COUCHII, Baird. 



Black Ground Squirrel. 



Spermophilus couchii, BAIRD, Pr. A. N. Sc. Phila. April, 1855, 332. 



SP. CH. Ears prominent ; tail cylindrical, full, about two-thirds the length of the body. Color entirely of a glossy 

 black. Length of body, 10 inches ; tail, 6| ; hind foot, 2 inches. 



This species is nearly the size of the black squirrel of Ohio, which it also greatly resem 

 bles in color. Its form is much like that of S. beeckeyi, though the tail is shorter. The ears 

 are quite large, thin, and squirrel-like, as in the last mentioned species ; they are uniformly 

 covered on both sides with short hairs. The thumb is armed with a short, broad, blunt nail, 

 not claw. The claws are well developed and strong, as in the genus, and moderately curved. 

 The soles are naked. The tail is about two-thirds the length of the body, and quite uniformly 

 and densely coated with stiff coarse hair as on the rest of the body. 



Color everywhere a uniform glossy black, without any other marking on the hairs, except a 

 little white about the edges of the mouth ; most lustrous on the tail. There is a little grayish 

 at the bases of some of the caudal hairs. 



Although the species is unquestionably a spermophile, it approaches the squirrels still 

 closer than the S. beecheyi and douglassii, and would be considered a squirrel but for the large, 

 strong, fossorial claws, and the characters of its skull and teeth. I take great pleasure in 

 dedicating it to Lieutenant Couch, its first discoverer. 



The collection of Dr. Berlandier contains several heads of this species collected at Victoria, Mex. 



This species, in some respects, resembles the Sciurus mustelinuti of Audubon and Bachman, 

 but is of a different genus, if these authors are correct in ascribing it to Sciurus. 



