Permanence and Evohition. 157 



It is simply an instance of over haste ; but there 

 are other things to be said which cut deeper into 

 the whole argument. 



It has been said, with great primd facie 

 appearance of justice, that the fact that scarcely 

 any mammals are found on remote islands 

 tells strongly in favour of derivation by 

 descent ; it does not appear why mammals 

 should not have originated on islands as easily 

 as other creatures. We know that they are 

 well capable of maintaining themselves there 

 wild when once introduced by man, while it is 

 easy to see the special difficulties there are 

 to their introduction in a state of nature. It is, 

 however, remarkable that many islands poor in 

 mammals contain other creatures whose trans- 

 port would seem to be equally difficult, as, for 

 instance, New Zealand, which contains ap- 

 parently no single indigenous mammal, contains 

 that remarkable wingless bird the Apteryx, and 

 contained within the recent period the still more 



