18 NORTH AMERICAN BATS. 



but extends between the fourth and fifth fingers. The basal joint 

 of the thumb is decorated with a whitish tuft. The posterior 

 surface of the interfeiuoral is very thickly covered over its whole 

 area with fur of the same color as that of the body. 



The difference in hue of the various individuals is chiefly owing 

 to the coloration of the tips of the hair. Each hair is tinged as 

 follows : — 



The base dark plumbeous in color, verging to black ; the centre, 

 *a delicate yellowish-brown, passing onwards toward the tip to a 

 darkish red, in some instances to a brighter red, more rarely to a 

 beautiful chocolate. The point is generally white. The grayish 

 chocolate and dark red varieties are the principal ones seen in 

 the northern specimens, while the bright red prevails among 

 those of warmer sections of the country. 



The hair covering the interfemoral membrane before and liehind 

 is indistinctly bi-colored ; the irregular growths scattered else- 

 where upon the alar membranes are unicolored. 



The color of the membranes is a rich brown, bordering on a 

 yellowish-brown, about the head. The ears and lips are marked 

 with yellow in the same manner as in the next species {L. 

 cinereus) they are marked with black. 



Fig. 15. Fig. 16. 



Skull small ; occiput high ; cranium broad. 

 Dentition. 



Molars . . Canines — . Incisors — . Canines _ . Molars — = 32 teeth. 



5 16 15 



Upper Jaw. — Incisors small, strongly convergent ; canines 

 simple. First i)reraolar very minute, entirely hidden from view 

 externally by the close position of the second premolar to the 

 canine ; molars not peculiar except the last, which is small and 

 thin, compressed from before backwards. 



Lowei^ Jaw. — Incisors crowded; canines pointing backwards. 



