286 THE DESCENT OF MAN 



the early progenitors of man might formerly have diverged 

 much in character, until they became more unlike each other 

 than any now existing races; but that subsequently, as sug- 

 gested by Vogt,"" they converged in character. When man 

 selects the offspring of two distinct species for the same ob- 

 ject, he sometimes induces a considerable amount of conver- 

 gence, as far as general appearance is concerned. This is 

 the case, as shown by Von Nathusius," with the improved 

 breeds of the pig, which are descended from two distinct 

 species; and in a less marked manner with the improved 

 breeds of cattle. A great anatomist, Gratiolet, maintains 

 that the anthropomorphous apes do not form a natural 

 sub-group; but that the orang is a highly developed gib- 

 bon or semnopithecus, the chimpanzee a highly developed 

 macacus, and the gorilla a highly developed mandrill. If 

 this conclusion, which rests almost exclusively on brain- 

 characters, be admitted, we should have a case of conver- 

 gence, at least in external characters, for the anthropo- 

 morphous apes are certainly more like each other in many 

 points than they are to other apes. All analogical resem- 

 blances, as of a whale to a fish, may indeed be said to be 

 cases of convergence ; but this term has never been applied 

 to superficial and adaptive resemblances. It would, how- 

 ever, be extremely rash to attribute to convergence close 

 similarity of character in many points of structure among 

 the modified descendants of widely distinct beings. The 

 form of a crystal is determined solely by the molecular 

 forces, and it is not surprising that dissimilar substances 

 should sometimes assume the same form; but with organic 

 beings we should bear in mind that the form of each de- 

 pends on an infinity of complex relations, namely, on varia- 

 tions due to causes far too intricate to be followed — on the 

 nature of the variations preserved, these depending on the 



'2 "Lectures on Man," £ng. translat., 1864, p. 468. 



^5 "Die Racen des Sohweines," 1860, s. 46. "Torstudien fiir Gesehichte, 

 etc., Schweinesohadel," 1864, s. 104. With respect to cattle, see M. de 

 Quatrefages, "Unite de I'Espeoe Humaine," 1861, p. 119. 



