FAMILY SCIURIDZ. 65 
S. capistratus. (Fox Squirrel of Bachman, p. 117.) Usually grey; ears and nose white; fur coarse. 
Tail longer than head and body. Length 29°5. Largest of the genus. Southern States, New- 
Jersey. 
S. lanuginosus. (Bacuman, p. 387.) Yellowish grey above, silver-grey on sides, beneath white. 
Tail shorter than the body. Palms and inner surface of toes thickly clothed with silky hairs. Fur 
softand downy. Length 14:0. Columbia River. 
S. nigrescens. (Bacumay, p. 334.) Black above, slightly varied with grey; sides of the neck, upper 
part of thigh and rump pale yellow, beneath soiled grey; feet black. Tail longer than body. 
Length 27°5. California. 
S. colle. (Ricuarpson, App. Beechy.) Above varied with black and yellow, beneath white; feet 
white; cheeks greyish. ‘Tail less than length of head and body. Length 20°1. 
GENUS PTEROMYS. Illger. 
Teeth as in the preceding genus. Ears round. Upper lip divided. Toes elongated, deeply 
divided. The skin dilated on the sides from the fore to the hind legs, forming a sort of 
parachute in the air. 
Ons. This genus at present embraces nine species, of which two are found in America, one 
in northern Europe, and the remainder in Java. Some of the species are nocturnal. 
THE SMALL AMERICAN FLYING SQUIRREL. 
PTEROMYS VOLUCELLA. 
PLATE XVI. FIG. 2.— (STATE COLLECTION.) 
Sciurus americanus volans: Ray, Synop. Quad. p. 215. 
Flying Squirrel. Penn. Hist. Quad. Vol.2, p. 153, No, 351. 
Sciurus volucella, GMELIN. 
Flying Squirrel. Penn. Arct. Zool. Vol. 1, p. 120. 
Pteromys volucella. HAruan, Fauna, p. 187. 
Common Flying Squirrel. Gopman, Am. Nat. Hist. Vol. 2, p. 147, figure. Emmons, Mass: Report, 1840, p. 69. 
Characteristics. Brownish ash, tinged with cream color on the body, above; darker on the 
membrane, which is bordered with white. Length 9°0 — 10°0. 
Description. Head short and rounded; muzzle rather obtuse. Ears large, broad, membra- 
nous, nearly naked, and 0°5high. Eyes large, brilliant and prominent. Whiskers numerous, 
some of them three inches in length. Claws feeble, compressed, convex and acute, nearly 
covered by hairs; the two middle claws of the fore feet subequal, longest on the hind feet, 
the inner toe shortest. Tail flat, distichous, linear, rounded at the tip, 1°2 broad. The fur 
particularly fine and soft ; on the extremities beyond the membrane, it is very short. 
Color. Head mouse-grey. Orbits of the eyes margined with black. Sides of the nose, 
cheeks, and all beneath pure white, with occasionally a slight tinge of reddish on the under 
Fauna. 9 
