Chap. "V I. Affinities and Genealogy. 153 



ages be so slightly changed as still to remain as species of the 

 same genus, whilst 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 strongly-marked dif- 

 ferences in some few points, — that is, to the amount of n)odifi- 

 cation undergone ; and how much to close resemblance in 

 numerous unimportant points, as indicating the lines of descent 

 or 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 Simiadse. This family is 

 divided by almost all naturalists into the Catarhine group, or 

 Old World monkeys, all of winch 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 premolars 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. It is therefore 

 against all probability that some New World species should have 

 formerly varied and 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 off-shoot from the 

 Old World Simian stem ; and that under a genealogical point of 

 view, he must be classed with the Catarhine division. 12 



The anthropomorphous apes, namely the gorilla, chimpanzee, 



-" This is nearly the same classifi- adae which answer to the Catarhines, 



eation as that provisionally adopted the Cebidae, and the Hapalidae, — 



by Mr. St. George Mivart (' Trail- these two latter groups answering 



6act. Philosoph. Soe.' 1867, p. 300), to the Platyrhines. Mr. Mivart 



who, after separating the Lemuridae, still abides by the same view; set 



divides the remainder of the Pri- ' Nature,' 1371, p. 481. 

 mates into the Hominida?, the Simi- 



8 



