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ZOOLOGY 



Ungulates 



Carnivora 



Chiroptera 



Primates 



Adaptations in Mammalia. — Mammals are considered the 

 highest type of all animals for reasons that have already been 

 given. Of the thirty-five hundred species, most inhabit conti- 

 nents; few species are found on different islands, and some, as the 

 whale, inhabit the ocean. They vary in size from the whale and 

 the elephant to tiny shrew mice and moles. Adaptations to 

 different habitat and methods of life abound ; the seal and whale 

 have the limbs modified into fins, the sloth and squirrel have 

 limbs peculiarly adapted to climbing, w^hile the bats have the fore 

 limbs modeled for flight. In those mammals known as rodents, 

 the teeth are so modified that on the upper and lower jaw two 

 prominent incisor teeth can be used for gnawing. These teeth 

 keep their chisel-like edge because the back part of the teeth is 

 softer and wears away more rapidl3^ The beaver fells trees with 

 them. We are all familiar with the destructive gnawing qualities 

 of one of the commonest of all rodents, the rat. 



Carnivorous Mammals. — As the word carnivorous denotes, 

 these animals are to a large extent flesh eaters. In a wild state 

 they hunt their prey, which is caught and torn with the aid of 

 well-developed claws and long, sharp canine teeth. These teeth, 



