19(3 THE DESCENT OF MAN. Part I. 



Siniiadse. This family is divided by almost all natura- 

 lists into the Catarhine group, or Old World monkeys, 

 all of which are characterised (as their name expresses) 

 by the peculiar structure of their nostrils and by having 

 four premolars in each jaw ; and into the Platyrhine 

 group or New World monkeys (including two very 

 distinct sub-groups), all of which are characterised by 

 differently-constructed nostrils and by having six pre- 

 molars in each jaw. Some other small differences might 

 be mentioned. Now man unquestionably belongs in 

 his dentition, in the structure of his nostrils, and some 

 other respects, to the Catarhine or Old World division ; 

 nor does he resemble the Platyrhines more closely than 

 the Catarhines in any characters, excepting in a few 

 of not much importance and apparently of an adaptive 

 nature. Therefore it would be against all probability 

 to suppose that some ancient New World species had 

 varied, and had thus produced a man-like creature with 

 all the distinctive characters proper to the Old World 

 division ; losing at the same time all its own distinctive 

 characters. There can consequently hardly be a doubt 

 that man is an offshoot from the Old World Simian stem ; 

 and that under a genealogical point of view, he must 

 be classed with the Catarhine division. 11 



The anthropomorphous apes, namely the gorilla, 

 chimpanzee, orang, and hylobates, are separated as a 

 distinct sub-group from the other Old World monkeys 

 by most naturalists. I am aware that Gratiolet, relying 

 on the structure of the brain, does not admit the exist- 



11 This is nearly the same classification as that provisionally adopted 

 by Mr. St. George Mivart (' Transact. Philosoph. Soc.' 1867, p. 300), 

 who, after separating the Lemuridoe, divides the remainder of the 

 Primates into the Hominidaj, the Simiadae answering to the Catarhines, 

 the Cebidae, and the Hapalidse, — these two latter groups answering to 

 the Plat vrl tines. 



