RODENTIA—SCIURINAE—SCIURUS RICHARDSONII. 273 
List of specimens. 
tT 5 a 5 
“ = Zz Ss 
3 £ 5 z : 
o > = bal 
3 z a aa 
a Locality. Whence obtained. : Nature of *S) z = & Collected by— 
= 3 specimen. 2 } 5 2 
5 = 3 S g 3 
g = = 3 = z= 
= a = 
6 5 = = S| 4 
520 | Sawatch Pass, Rocky Mountains..) Capt. E. G. Beckwith........| 18 | Skin......... 8.00 5.00 6.50 1.05 | Mr. Kreutzfeldt. 
SCIURUS RICHARDSONII, Bach. 
Richardson’s Squirrel. 
Sciurus richardsonii, Bacuman, Pr. Zool. Soc. Lond. VI, 1838, 100.—Is. Charlesworth’s Mag. N. H. III, Aug. 1839, 
385.—In. Jour. Ac. N. Sc. Phil. VIII, 1, 1839, 64 —In. Townsend’s Narrative, 1839, 318. 
Avp. & Bacu. N. Am. Quad. I, 1849, 41; pl. v. 
Sciurus hudsonius, var. 8, Ricu. F. Bor. Am. I, 1829, 190. 
? Sciurus lanuginosus, Bacuman, Pr. Zool. Soc. Lond. VI, 1838, 101.—Is. Charlesworth’s Mag. N. H. III, Aug. 1839, 
387.—In. Jour. A. N. Sc. Phila. VIII, 1, 1839, 67.—Is. Townsend’s Narr. 1839, 320. 
Waener, Suppl. Schreb. III, 1843, 180. 
Aup. & Bacu. N. Am. Quad, I, 1849, 199; pl. xxv. 
Sp. Cu.—Size larger than the Hudson’s Bay squirrel. Ears with long hairs, presenting the appearance of tufts. Tail 
shorter than the body. Under surface of feet hairy from heel to metatarsals; then nearly naked. Above, reddish brown, 
varied with annulations of black, lighter on the sides; beneath, dull white; a dark line separating colors of sides from belly. 
Tail bushy, sub-cylindrical, dark reddish brown in the centre, entirely of a pure glossy black at tip. The hairs all long and 
coarse. Hairs on the tail generally, (except at tip,) glossy black beyond the rufous portion, and more or less tipped with paler 
rusty. 
General appearance that of S. hudsonius, or the chickaree, although larger. Whiskers longer 
than the head, black. Ears large, rather sparsely clothed on their back with long hairs, which 
at the base are four lines long, and but little shorter towards the tip; the ends of the hairs, 
projecting beyond the margins of the ears, present the appearance of tufts ; on the concavity of 
the ear the hairs are very short. 
The limbs are moderately developed ; the thumb a mere callosity ; the fourth finger longest ; 
third scarcely shorter; the second and fifth nearly equal. The claws are much as in S. hud- 
sonius ; the palms are naked ; the hind foot from the heel is shorter than in the other species ; 
the fourth toe is longest ; the third and second successively and slightly shorter; the fifth comes 
to the base of the claw of the fourth ; the first reaches to the base of the claw of the fifth; the 
under surface of the foot, from heel to metatarsals, is densely clothed with hair, the soles naked 
or with a few scattered hairs under the toes. Claws smaller than in S. hudsonius. Tail shorter 
than the body, little flattened, hairs at the extremity very long. 
The prevailing tint of the upper parts is dull rusty or reddish brown; the hairs being lead 
color at the base, then annulated with black and dark chestnut brown. In some specimens 
this tint is diffused over the whole back, in others more confined to the dorsal region; along 
the sides of the body the ferruginous is a good deal lighter, imparting a grayish tint. The 
outer surfaces of fore legs and of hind foot are brighter ferruginous, paler on the latter. The 
under parts are of a dull brownish, or very pale rusty white; and there is a distinct line of 
dusky on the flanks, separating the upper and under color. In some specimens the lower edge 
35 L 
