Evolution 



and by their generally large number of teeth, which reach a total 

 of fifty or fifty-two in some species, whereas forty-four is the 

 ordinary maximum number in the main mammal group. This 

 last is to be regarded as a character derived from the reptiles. 



It is very interesting to observe how, in Australia, where 

 the Marsupials have been free from the competition of other 

 mammals, they have evolved along many of the same general 

 lines as the higher group. We have indeed no marsupial whales, 



FlG. 109. Newborn young 

 of Kangaroo. 



FIG. 108. Kangaroo, with young. 



bats, or seals, but there is a mole, very similar in its appearance 

 and habits to our European species, and a carnivorous type which 

 closely resembles a wolf or jackal; again we have bandicoots, 

 occupying the same place in nature as our rabbits and other 

 rodents ; tree-dwelling, squirrel-like forms ; and kangaroos, 

 which compare in their mode of life, if not in their appearance, 

 with the cattle, deer, and antelopes of other countries. The Mar- 

 supials are illustrated in Figs. 108 to 113. This group, so far as 

 can be judged from fossils, is considerably older than that of 



130 



