CLASS MAMMALIA. 



199 



FIG. 346. 





for crushing its insect food. Its flight is that of a bird, 

 though fluttering and lacking ease of movement. Dur- 

 ing the day it hides in caves, lofts, etc., and commonly 

 ventures out only with the 

 twilight. Its eye is small 

 and apparently of little serv- 

 ice, as it flits among bushes 

 and intricate passages when 

 blinded.* Associated with 

 ideas of gloom, it inspires 

 universal dread, yet some spe- 

 cies render great service by 

 devouring noxious insects. 

 To capture these it curves 

 forward that part of the mem- 

 brane expanded between the 

 hind legs and tail, to serve as a net. Its flight is un- 

 certain and awkward, as ever and anon it dives down- 

 ward, apparently making complete somersaults in its 

 effort to take the "catch" from the net. The common 

 North American Bats are of small size, feed on insects, 

 and have the hind legs joined by a transverse mem- 

 brane which includes the tail. The following table will 

 distinguish the more common genera : 



Geoffrey's Bac. 



EARS ENOEMOUS. Incisors 



EARS OF MODERATE SIZE. Incisors 

 EARS OF MODERATE SIZE. Incisors 



2-8 

 3 3' 

 1 1 



2 2 

 33' 



Pleca/tin. 



Atalajiha. 



Vespertilio. 



* This has led some Zoologists to think that it has a sixth sense. It is prob- 

 ably due, however, to its extraordinary delicacy of touch. The cry of a bat is so 

 shrill that many persons' ears can not detect it, and Homer (Odyssey, 24, 6) com- 

 pares it to the cries of ghosts. The bat is frequently infested with the common 

 bed-bug (' mex lee tv la' n ?/,<), and this fact may answer the question of the despair- 

 ing housewife, " Where can the biigs come from ? " 



