SKELETON OF BATS 



523 



more strongly developed 

 in males than in females, 

 and may perhaps be 

 partly relegated to the 

 category of secondary 

 sexual characters. But 

 it seems that they have 

 also an important tactile 

 function, and enable the 

 creatures to fly witliout 

 touching bodies which 

 intrude themselves upon 

 tlieir way. The ears, 

 too, are frequently very 

 large, and it may be 

 supposed that tlie sense 

 of hearing is correspond- 

 ingly acute. In the 

 common Long-eared Bat 

 of this country, the ears 

 are not greatly inferior 

 in length to tlie head 

 and body of tlie animal 

 combined. The ears are 

 of every variety of shape, 

 and offer characters 

 which are valual)le in 

 the systematic arrange- 

 ment of the memljers of 

 the order. 



In tlie skull of Bats 

 there is very rarely a 

 complete separation Ije- 

 tween the orbital and 

 temporal fossae ; the 

 lachrymal duct is out- 

 side the orbit. The 

 tympanies are annular, 

 and in a rudimentary 

 condition. The centra 



