144 



APES, MONKEYS, AND LEMURS 



any American monkey from all those of the Old World, except the larger Man-like 

 Apes, with which there is not the slightest fear of its being confounded. Then, 

 again, all the monkeys of the New World are characterized by the absence of cheek 

 pouches ; so that whenever we see a monkey cramming nuts into his cheeks we may 

 be perfectly sure that he does not come from America. It is true, indeed, that this 

 absence of cheek pouches will not help us to distinguish an American monkey from 

 an Indian langur or an African thumbless monkey, but then both the latter have 

 naked callosities on the buttocks. Moreover, if we were to dissect an American 



THE RED-FACED SPIDER-MONKEY. 



(One-fifteenth natural size. ) 



monkey, we should find that it had a simple stomach, quite different from the sac- 

 culated one which characterizes the langurs and thumbless monkeys. 



Another peculiarity of some, although unfortunately not all, of the American 

 monkeys is that the tail is prehensile, and capable of being coiled round a bough so as 

 to form a most efficient aid in climbing. These prehensile tails are characteristic 

 only of the howlers and the spider-monkeys, and their kin ; the tails of the titis and 

 their allies being nonprehensile, like those of the Old World monkeys. The reader 



