ORDER CARNASSIER. 3 



der-blades to give the shoulder the requisite degree 

 of solidity ; but it was incompatible with the rota- 

 tion of the fore-arm, which would have weakened 

 the force of the impetus necessary for flight. All 

 of these animals have four large canine teeth, but 

 the number of the incisors vary. They have long 

 been divided into two genera according to the extent 

 of their organs of flying; but the first of these two 

 requires many subdivisions. 



The Bats ( Vespertilio, Linn.) 



Have the arms, the fore-arms, and the fingers ex- 

 tremely elongated, and those with the membrane 

 which fills up the intervals between them, form real 

 wings, as much extended as those of birds. Ac- 

 cordingly the bats fly to a considerable height and 

 with great rapidity. Their pectoral muscles possess a 

 thickness proportioned to the movements which they 

 are designed to execute, and in the middle of the 

 sternum is a ridge like that of birds, to form a point 

 of attachment for these muscles. The thumb is 

 short and armed with a hooked nail, which these 

 animals make use of to hang by and to creep. 

 Their hind-feet are weak, divided into five toes of 

 equal length and all of them are armed with nails. 

 There is no caecum to their intestines. Their eyes 

 are extremely little, but their ears are often remark- 

 ably large ; and, together with their wings, form an 

 enormous extent of membranous surface. This is 

 almost naked, and so sensible, that the bats can di- 



B 2 



