276 DARWIN1ANISM. 



interpose here. It was the freedom of cross that kept 

 bat and seal up to type ; and so it is the like freedom of 

 cross in great communities that wipes out special marks. 

 Isolate these particularised individuals, and the particu- 

 larity might not revert. It is not so certain, again, fin- 

 all that, that isolation has any such power. Consult the 

 references to isolation in the Life and Letters ; and Mr. 

 Darwin will be found, as he says himself, to " oscillate 

 much." At one time (iii. 160) he was "all for isola- 

 tion " at another he " doubted much." 



Certainly, too, it is the case that if isolation is to be 

 the principle relatively effective, it is not well possible 

 to place that principle more favourably than in the 

 Galapagos. I question, and on his own showing, the 

 partial isolation from island to island; but there can be 

 no question in regard to the continent of South America 

 and the insular archipelago in itself generally. 



Again, nevertheless, even so, may not the simple con- 

 ditions really do all that Mr. Darwin would ascribe to 

 his own ingenuities of conception ? I have urged this in 

 the Lectures. If strange conditions are at all to act, 

 surely no stranger conditions can be found than those 

 that these islands display. Mr. Darwin himself, as we 

 have seen (Journal, p. 492) " can hardly doubt " that the 

 imported rats and mice " have varied from the effect of 

 the new conditions to which they have been exposed ; " 

 and if these, why not also the remarkable finches ? 

 Then what of the tortoises and lizards, which likewise are 

 so peculiar ? " From what country " the latter arrived 

 if they did arrive " it is impossible to say, as their 

 affinity is not very clear to any known species," and it is 

 out of the question to think, in their connection, of the 

 monstrous lizards of the Secondary Epochs. The huge 

 tortoise, again, is called "aboriginal," "it is found no- 

 where else in this quarter of the world." " It may be 



