SCIUROPTERUS. 109 



Color. Upper parts hair brown, grading to isabella; ears, feet and 

 hands above, and upper surface of tail sooty; black orbital ring; 

 under parts grayish white; under surface of tail drab shading to sooty. 



Mfasiiifiinnts. Type. Total length, 214; tail vertebra', 92; hind 

 foot, iS. 



141. volans. [MiiS], Linn. S>st. Xat., 1776, i, p. ,S5, (Mus, nee Sciu- 

 rus, p. JSS). 



7<oliicella Pall., Nov. Spec. Glir., 17X8, p. 351. 



Type locality. I 'irginia . 



Gfoj:;r. Distr. Northern New York and southern New Hamp- 

 shire to Florida, west to the plains. 



Genl. Char. Size medium; winter and summer pelage alike in 

 color; hairs of under parts white to base. 



Color. Upper parts drab shaded with russet, tail slightly darker 

 above, beneath buffy gray; hands above grayish white, feet drab; 

 black orbital ring, and broad black band at edge of wing membrane; 

 under parts pure white, washed in some specimens with buff. 



Measurements. Total length, 234.5: tail vertebra', 99.6; hind 

 foot, 31-4. 



<i .^qicrceti . [.Seiuro/>lera), Bangs, Proc. Biol. Soc. Wash.. i8g6, 

 p. 166. 



Type locality. Citronelle, Citrus count)-, Florida. 



Geogr. Distr. Peninsular Florida to southern Georgia; west to 

 Louisiana? 



Genl. Char. Similar to .S. volans, more uniform russet, under 

 parts and tail beneath washed with same color. 



Color. Upper parts russet, grading to yellowish drab, feet and 

 hands above sooty gray; edge of wing membrane black; under parts 

 white tinged with pinkish russet. Tail, above smoky gray tinged 

 with rusty, beneath pinkish buff. 



.\feasurements. Total length, 237.66: tail vertebra, 102.66; hind 

 foot, 31.33. 



b.—aliiinus. {Fteromys), Rich. Faun. Bor., 1S29, p. 195, pi. 18. 



Type locality. Head waters of Elk River, N. W. Alberta. 



Geogr. Distr. From the Mackenzie River along east side of the 

 Rocky Mountains to United States border. 



Genl. Char. Head and feet larger than .V. sahrinus: tail longer, 

 elliptical; membrane less full, border straight. 



Color. Upper parts yellowish brown, tail blackish brown: under 

 parts grayish white, tail beneath pale brown. 



Measurements. Total length. 280; tail vertebra', 108. 



