320 PLEASANT WA YS IN SCIENCE. 



have been.) If the descendants of those twelve families 

 had never intermarried with outside families in such son 

 that the descendants of such mixed families came to be 

 regarded as true Hebrews, we should have in the Hebrews a 

 race corresponding to the Simiadae as regarded by Darwin, 

 i.e., a race entirely descended from one set of families, and 

 so constituting, in fact, a single family. But we know that, 

 despite the objections entertained by the Hebrews against 

 the intermixture of their race with other races, this did not 

 happen. Not only did many of those regarded as true 

 Hebrews share descent from nations outside their own, but 

 many of those regarded as truly belonging to nations out- 

 side the Jewish race shared descent from the twelve sons of 

 Jacob. 



The case corresponding, then, to that of the purest of all 

 human races, and the case therefore most favourable to the 

 view presented by Darwin (though very far from essential to 

 the Darwinian theory), is simply this, that, in the first place, 

 many animals regarded as truly Simiadae share descent from 

 animals outside that family which Darwin regards as the ape 

 progenitor of man ; and, in the second place, many animals 

 regarded as outside the Simiadae share descent from that 

 ape-like progenitor. This involves the important inference 

 that the ape-like progenitor of man was not so markedly 

 differentiated from other families of animals then existing, 

 that fertile intercourse was impossible. A little consideration 

 will show that this inference accords well with, if it might 

 not almost have been directly deduced from, the Darwinian 

 doctrine that all orders of mammals were, in turn, descended 

 from a still more remote progenitor race. The same con- 

 siderations may manifestly be applied also to that more 

 remote race, to the still more remote race from which all the 

 vertebrates have descended, and so on to the source itseli 

 from which all forms of living creatures are supposed to 

 have descended. A difficulty meets us at that remotest end 

 of the chain analogous to the difficulty 01 understanding how 

 life began at all; but we should profit little by extending 



