AFFINITIES AND GENEALOGY, 173 



It must not be supposed that the resemblances between 

 man and certain apes in the above and in many other 

 points sucli as in having a naked forehead, long tresses on 

 the head, etc. are all necessarily the result of unbroken 

 inheritance from a common progenitor, or of subsequent 

 reversion. Many of these resemblances are more probably 

 due to analogous variation, which follows, as I have else- 

 where attempted to show,* from co-descended organisms 

 having a similar constitution, and having been acted on by 

 like causes inducing similar modifications. With respect 

 to the similar direction of the hair on the forearms of man 

 and certain monkeys, as this character is common to almost 

 all the anthropomorphous apes, it may probably be attribu- 

 ted to inheritance; but this is not certain, as some very 

 distinct American monkeys are thus characterized. 



Although, as we have now seen, man has no just right to 

 form a separate Order for his own reception, he may per- 

 haps claim a distinct sub-order or family. Prof. Huxley, 

 in his last work,f divides the Primates into three sub- 

 orders; namely, the Anthropidag with man alone, the Simi- 

 adae, including monkeys of all kinds, and the Lemuridae 

 with the diversified genera of lemurs. As far as differ- 

 ences in certain important points of structure are concerned, 

 man may no doubt rightly claim the rank of a sub-order; 

 and this 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 common stock, it is quite conceivable that two of 

 them might after the lapse of ages be so slightly changed 

 as still to remain a 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 



Martin, 1841, p. 415. Also, Isid. Geoff roy on the American monkeys 

 and other kinds, "Hist. Nat. Gen.," vol. ii, 1859, pp. 216, 243, 

 Eschricht, ibid, ss. 46, 55, 61. Owen, " Anat. of Vertebrates," vol. 

 iii, p. 619. Wallace, " Contributions to the Theory of Natural Selec- 

 tion," 1870, p. 344. 



*" Origin of Species," 5th edit., 1869, p. 194. "The Variation of 

 Animals and Plants under Domestication," vol. ii, 1868, p. 348. 



f "An Introduction to the Classification of Animals," 1869, p. 99. 



