No. 1. 
REPORT UPON MAMMALS COLLECTED ON THE SURVEY. 
BY S. F. BATED. 
SCIURUS FREMONTII, Towns.—Small Mountain Gray Squirrel. 
Plate XI. 
Sciurus fremontii, (“ Townsend,”) Aud. & Bach. N. Am. Quad. Ill, 1853, 237; pi. cvlix, fig. 1. 
Baird, Gen. Kep. Mammals. 1857, 272. 
Sp. Ch. —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 only specimen of this species collected by any of the recent expeditions was obtained in 
the Sawatch Pass. (No. 18.) 
T AMI AS QUADRIVITTATUS, Wagner .—Missouri Striped Squirrel. 
Sciurus quarlrivittatus, Say, in Long’s Exped. R Mts. II, 1823, 45. 
Tamias quadrivittatus, Wagner, Suppl. Schreb. Ill, 1843, 234. 
Aud. & Bach. N. Am. Quad. I, 1849, 195; pi. xxiv. 
Baird, Gen. Rep. Mammals. 1857, 297. 
Sp. Ch. —Tail, with the hairs, nearly or quite as long as the body. A grayish white stripe along the top of the head, with 
branches passing above and below the eye. The stripe bordered above and below by darker ones, and separated behind the eye 
by a dark lino. A gray or hoary patch behind the ears. Sides of body deep ferruginous; back with five about equidistant dark 
stripes, nearly black on the posterior part of the body, their intervals forming four grayish white lines of similar dimensions to 
them. Tail, when flattened out, ferruginous externally, then black, then ferruginous. Body beneath, dirty grayish white. 
Length, 4 to 5 inches. Hind foot, 1.20 inch. 
A specimen was collected in the Sangre del Christo Pass. 
CYNOMYS GUNNISONII, Baird .-Short-tailed Prairie Dog. 
Plate IV, Fig. 2. 
Cynomys gunnisonii, Baird, Pr. A. N. Sc. Phil. VII, April, 1855, 334.—lb. Gen. Rep. Mammals, 1857, 335. 
P Arctomys columbianus, 1 Ord, in Guthrie’s Geog. 2d Am. ed. II, 1815, 292, 302. 
?? Anisonyx brachyura, Raf. Am. Month. Mag. II, 1817, 45. 
P. Arctomys brachyura, Harlan, F. Amer. 1825, 304. 
Fischer, Synopsis, 1829, 345. 
P. Burrowing squirrel of Columbia, Lewis and Clarke, II, 1815, 173. 
Sp. Ch.— Size less than that of the S. ludovicianus, general proportions similar. Ears very short ; thumb armed with a well 
developed claw. Tail short, the vertebral portion less than one-sixth the length of the body; with the hairs, less than one-fourth; 
Color above rather light liver brown, mixed intimately with ash, light brown, and black; beneath pale yellowish brown. Tail 
