158 BULLETIN NO. VII. 



clear whitish-gray, with a dorsal area of yellowish-brown. 

 Under parts white; sometimes jet black, with all intermediate 

 phases. Hairs of the tail white-tipped, with a subterminal 

 band of black, and black ampliations upon the brownish basal 

 portion. Lower parts rarely suffused with rufous. Ears gen 

 erally with a tuft of white behind at the base, not penciled. 

 Length, 10.50; tail, 11.50; tail vertebrae, 8; fore foot, 1.75; hind 

 foot, 2. 50. As a rule the males seem to be larger, but perhaps 

 there is no sexual variation. The top of the head is generally 

 clear, dark-gray, while often there is a lateral yellowish line. 



It is curious that the melanistic phases seem to be local and 

 confined to narrow limits. 



The southern variety of this species is considerably smaller 

 and decidedly less white. The two varieties pass into each 

 other. Variety leucotis extends throughout the northern United 

 States and southern Canada westward to the eastern border of 



the plains, and southward to the isotherm of 56 F. 







Sciurus niger LINN. 



FOX SQUIKREL. 



PLATE VIII.* 



The varietal distinctions set up for the various phases of this 

 species are of very unimportant nature. Our specimens are all 

 of the variety ludovicianus. Length of body, 11-14; tail, to end of 

 vertebrae, 8 . 50 10 . 50. Above gray, with much suif used rufous 

 or sienna red ; ears, feet and lower parts rusty red, varied with 

 more or less dusky. The under surface is sometimes nearly 

 black. Specimens from the far west are paler, those from the 

 south more reddish below. The variety ludovicianus is confined 

 to the area drained by the Mississippi and its tributaries. 



The gray squirrel seems more common in most parts of the 

 state, but the distribution is remarkably capricious. 



GENUS SCIUROPTERUS, F. Cuv. 



The flying squirrels are represented in North America by 

 but a single species extending from the Atlantic to the Pacific 

 and subject to great geographical variation. 



The skull is short, broad, and strongly curved, orbits large, 

 interorbital region constricted, pterygoid processes slender, 



*The plate is intended as an illustration of the adaptability of native animals to 

 decorative art. The present case being a tile in which conventionalization is intro- 

 duced into the accessories simply in order to highten contrasts otherwise too slight to 

 be available for such purposes. 



