MAMMALS 



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structure, are commonly included in one species. The 

 chief structural characteristics which distinguish man from 

 the other members of this order are the great develop- 

 ment of his brain and the non-opposability of his great 

 toe. Despite the similarity in general structure between 

 him and the anthropoid apes of the Old World, in par- 



FlG. 215. — " Bob Jordan," a monkey of the genus Ceraipitheciis. (Photo- 

 graph from life by D. S. Jordan.) 



ticular the chimpanzee and orang-outang, the disparity in 

 size of brain is enormous. 



The lowest Primates are the lemurs found in Madagas- 

 car, in which island they include about one-half of all the 



