THE VERTEBRATA 



I6 3 



certain characteristics in common with the car- 

 nivora, herbivora, and rodents, belonging to the 

 Eutheria. One of the herbivorous marsupials is 

 the Great Kangaroo, Macropus. It gets its name, 

 Large-foot, from the size of its hind-paws ; on 

 these it stands, and by their aid it takes remarka- 

 bly long leaps. Its skull is shown in Fig. 45 ; 

 this, however, has not the full set of teeth, some 

 of which are soon shed. It crops the herbage 

 with its front teeth, and grinds it with its back 

 teeth, like other 

 herbivora. 



The study of the 

 teeth is of great 

 help in the classifi- 

 cation of the Mam- 

 malia. Oftheeight 

 orders of the Eu- 

 theria, two alone, 

 the Sloth order 

 and the Whale or- 

 der, show a tend- 

 ency to the sup- 

 pression of the 

 teeth. Those of 

 the herbivora and 

 carnivora may eas- 

 ily be compared 

 by anyone, in the FIG. 46. Skull and lower jaw of Ro- 



chpfn anrl the> Hncr dent; *', *', incisor teeth, separated by 



sheep and the dog a long ' interval from the molar / < 

 respectively. Fig. About one-half the natural size. 

 46 shows the skull 



of a Rodent, with elongated front teeth, adapted 

 for that persistent gnawing which makes the ani- 

 mals of the order, such as the Rat and Rabbit, so 

 terribly destructive. 



