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VERTEBRATE AKIMAL8 MAMMALIA DIAGRAM 3. 



Skull of hedgehog. 



Skull of a dog. 



2nd. The Insectivora which are 

 all small mammals feed on insects. 

 In order to crush them, they 

 have molar teeth, set with pro- 

 jecting points. Among the in- 

 sectivora may be mentioned the 

 bats, the moles, the shrew-mouse 

 and the hedgehog. 



3rd. The Carnivora form an order 

 including the large mammals which 

 generally feed on flesh ; their molar 

 teeth are always more or less pointed 

 1 n order to divide their food, and they 

 have very strong canines to tear it. 

 In the order camivora we find the family of the bears, the 

 badger, the family of the weasels, those of the cats and dogs, 

 and lastly, that of the seals. 



4th. The Jtodentia.The 

 mammals of this order 

 feed exclusively on vege- 

 table matters, as the car- 

 nivora feed principally on 

 animals. Consequently 

 we find the most injurious 

 mammals among the ro- 

 SkuU of a rodent. dents. Some of them, are 



valued for their skins. It is sufficient to compare the teeth of a 

 rodent, a rabbit, for instance, with those of a carnivorous animal, 

 to see that they cannot feed in the same manner. The rodents 

 have very strong incisors, which cut crosswise, with which they 

 can cut wood ; they have no canines, and their molars are flat to 

 crush their food. JBut this is not all : the incisors are quickly 

 Worn down by cutting such h ard substances ; and therefore 

 while the teeth of man and carnivora do not grow after they 



