﻿MYOTLS LUCIFUGUS. 



61 



Fur and color. — The distribution of the fur in Myotis lucifugus is in 

 no way peculiar. Tlie hairs are everywhere dusky slate at base. 

 General color dull brown with a distinct gloss in certain lights, the 

 ventral surface paler and more yellowish. The exact shades are vari- 

 able. Thus in three specimens taken at Washington, D. C, in June, 

 the color of the back is respectively wood brown, raw umber, and 

 sepia, the belly in each pale wood brown tinged to a varying degree 

 with gray. In the majority of individuals the color tends toward 

 sepia. Seven skins from Elk Eiver, Minn., and three from Kadiak 

 Island, Alaska, are indistinguishable in color from those taken at 

 Washington. Ears and membranes light brown. 



Skull. — The skull of Myotis lucifugus is characterized by the broad 



Fig. 14. — Teeth of (a) Myotis yumanensis, (b) lucifugus, (c) M, lucif ugiis longicrus, and 

 (d) M. velifer (X 5). 



muzzle and palate and gradually sloping forehead. In most specimens 

 the face line begins to rise almost from the tip of the muzzle j in others, 

 however, there is a short flat area back of the nasal opening. The 

 brain case is broad and inflated at the back, less so in front, produc- 

 ing in many individuals a wedge-shaped outline. Distance from pos- 

 terior molar to tip of hamular less than distance between posterior 

 molars. 



The skull of Myotis lucifugus differs from that of M. suhulatus in its 

 slightly smaller size, broader palate and muzzle, and less abruptly 

 elevated face line. 



Tee^/t. —Upper incisors diverging at tips (fig. 14 Z?). Crown of first 

 bicuspidate, and, when viewed from below, nearly rectangular and 



