158 SCIUROPTERUS. 
118. volans (Mus.) Linn., Syst. Nat., 1, 1758, p. 63; 1, 1776, p. 85. 
(nec Sciurus, p. 88.) 
volucella Pall., Nov. Spec. Glires, 1788, p. 351. 
volans (Scutropterus), Elliot, Syn. N. Am. Mamm., 1901, p. 109. 
FLYING SQUIRREL. 
Type locality. Virginia. 
Geogr. Distr. From northern border of Mexico into Guatemala, 
Central America. In United States to northern New York and 
southern New Hampshire; not in Florida. 
Genl. Char. Size medium; winter and summer pelage alike in 
color; hairs of under parts white to base. 
Fic. XXXIII. SclUROPTERUS VOLANS. FLYING SQUIRREL. 
Color. Upper parts drab shaded with russet, tail slightly darker; 
hands above grayish white, feet drab; black orbital ring; under parts 
pure white, washed in some specimens with buff. 
Measurements. Total length, 234.5; tail vertebrae, 99.6; hind 
foot, 31.4. Skull: occipito-nasal length, 34; Hensel, 27; zygomatic 
width, 20; interorbital width, 7; palatal length, 9; length of upper 
molar series, 6. 
Largest of North American rodents, attaining a weight of fifty 
pounds or more, the Beaver, which at one time extended its range 
over nearly all forest-covered land in the northern Hemisphere, has 
