Animals Before Man 



peculiarities is clear when we know that the 

 aye-aye feeds largely on wood -boring grubs. 

 The sharp front teeth cut readily through the 

 bark and wood in which the grubs dwell, and 

 the long finger is used to coax them out of their 

 burrows. So, if we only knew the food of 

 some of these old animals, the reason for the 

 strange shape of their teeth might be evident. 



A peculiar feature of some of the early 

 marsupials, the polyprotodonts, is the number 

 of their teeth. Nowadays no mammal save 

 the porpoise has more than 44 teeth ; but Dro- 

 matherium possesses 56, and Stylacodon no 

 fewer than 68. This abundance of teeth is a 

 slight suggestion of affinity with reptiles, in 

 which, it may be remembered, teeth are numer- 

 ous, but of one pattern in any given species.* 

 And it may be recollected, too, that in speak- 

 ing of worms and trilobites it was noted that 

 mere repetition or multiplication of similar 

 parts is no real increase in complexity of struc- 

 ture, although it may appear so at first sight. 



* The anomodonts, of course, excep'ted ; but then they furnish 

 exceptions to a great many rules. 



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