Order CHIROPTERA 



67 



9. 



and fingers brown or black; upper jaw with 1 or 3 pairs 



of premolars 8 



Upper jaw with 1 pair of incisors; tragus curved and less 



than 4 mm. (about 1/^ in.) from notch to tip 



evening bat, Nycticeius humeralis 



Upper jaw with 2 pairs of incisors; tragus straight and 



more than 4 mm. from notch to tip 9 



Ear large, extending 3 or 4 mm. (about l/g in.) beyond end 



of snout when laid forward ; tragus slender and pointed, 



fig. S\b Keen's bat, Myotis keenit 



Ear not extending 3 or 4 mm. beyond end of snout when 



lad forward ; tragus broadly rounded, fig. 51a 10 



Fig. 51. — Ears of two bats: a, little brown bat; b, Keen's bat. 



10. Fur on under side of body white or pale gray; fur on upper 



side of body dense, woolly, and brown, with a mole-gray 



cast; nose flesh-colored in living bat 



southeastern bat, Myotis austroriparw.s 



Fur on under side of body buffy gray or pinkish gray; fur 

 on upper side of body long, straight, brown, but without 

 a mole-gray cast; nose dark colored in living bat 11 



11. Forearm less than 35 mm. (1^8 inJ long; foot not more 



than 8 mm. (less than ^ in.) long 



small-footed brown bat, Myotis subiilatus* 



Forearm more than 35 mm. long; foot more than 8 mm. 

 long 12 



12. Fur on upper parts of body with coppery or bronzy tipped 



hairs; on under parts buffy gray; calcar lacking a def- 

 inite keel; foot usually 10 mm. long 



little brown bat, Myotis lucifugus 



*This species may occur in Illinois, but there are no official records of it. 



