220 DARWINISM STATED BY DARWIN HIMSELF. 



rank is too low, if we look chiefly to his mental faculties. 

 Nevertheless, from a genealogical point of view, it appears 

 that this rank is too high, and that man ought to form 

 merely a family, or possibly even only a sub-family. If 

 we imagine three lines of descent proceeding from a com- 

 mon stock, it is quite conceivable that two of them might 

 after the lapse of ages be so slightly changed as still to 

 remain as species of the same genus, while the third line 

 might become so greatly modified as to deserve to rank 

 as a distinct sub-family, family, or even order. But in 

 this case it is almost certain that the third line would 

 still retain through inheritance numerous small points 

 of resemblance with the other two. Here, then, would 

 occur the difficulty, at present insoluble, how much 

 weight we ought to assign in our classifications to strong- 

 ly-marked differences in some few points — that is, to the 

 amount of modification undergone — and how much to 

 close resemblance in numerous unimportant points, as 

 indicating the lines of descent of genealogy. To attach 

 much weight to the few but strong differences is the most 

 obvious and perhaps the safest course,, though it appears 

 more correct to pay great attention to the many small 

 resemblances, as giving a truly natural classification. 



In forming a judgment on this head with reference to 

 man, we must glance at the classification of the Simiadce. 

 This family is divided by almost all naturalists into the 

 Catarrhine group, or Old World monkeys, all of which 

 are characterized (as their name expresses) by the peculiar 

 structure of their nostrils, and by having four premolars 

 in each jaw ; and into the Platyrrhine group or New World 

 monkeys (including two very distinct sub-groups), all of 

 which are characterized by differently constructed nos- 

 trils, and by having six premolars in each jaw. Some 

 other small differences might be mentioned. Now man 



