MAMMALIA. 



The vertebrated animals fall naturally into four great classes. These 

 four classes are termed Mammals, Birds, Reptiles, and Fishes, their 

 precedence in order being determined by the more or less perfect de- 

 velopment of their structure. 



QUADRUMANA, OR THE MONKEY TRIBE. 



The QuADRUMANOUS, or four-handed, animals are familiarly known 

 by the titles of Apes, Baboons, and Monkeys. 



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Group of Monkeys in the Zoological Garden, Philadelphia. 



The Apes are at once distinguished from the other Quadrumana by 

 the absence of those cheek-pouches which are so usefully employed as 

 temporary larders by those monkeys which possess them ; by the total 

 want of tails and of those callosities on the hinder quarters which are 

 so conspicuously characteristic of the baboons. 



