RELATIONSHIP OF SPECIES. 101 



genealogically till hundreds of years before this, till perhaps 

 before the time of the North Sea. 



However, the Porto Santo Rabbit, isolated in a restricted 

 environment, has apparently become very subject to evolutionary 

 duction. It has apparently altered in habit, size, and structure, 

 and now refuses to breed with ordinary Rabbits. One should 

 say, therefore, that it is "further" in relationship to the 

 Continental Rabbit than the latter is to the English, though 

 genealogically this is by no means the case. 



It is curious to note that this Porto Santo Rabbit, although it 

 differs from the common type in all the above points, is but 

 merely classified as a subspecies of Lepus (or rather Oryctolagus) 

 cuniculus. What is the reason for this ? None other, I should 

 imagine, than the fact that we are unconsciously influenced by 

 the fact that we know it has only evoluted out in the short 

 space of six hundred years. Were this not known, would it not 

 be held at least a distinct species ? However, it seems absurd 

 to liken the differences between this form and the common 

 Rabbit to the usual small subspecial distinctions that generally 

 hold good. 



Are we not to consider different forms as different species 

 because they have come quicker into being than perhaps often 

 happens ? If so, this strikes at the mutation theory. 



(To be continued.) 



