226 Darwin, and after Darwin. 



to cross those distances of ocean : consequently, there 

 is only one instance of a peculiar species of bird or 

 bat namely, a bull-finch in the Azores, which, being a 

 small land-bird, is not likely ever to have had any 

 other visitors from its original parent species coming 

 over from Europe to keep up the original breed. 

 Lastly, it is very much more easy for insects and 

 land-mollusca to be conveyed to such islands by wind 

 and floating timber than it is for terrestrial mammals, 

 or even than it is for small birds and bats ; but yet 

 such means of transit are not sufficiently sure to admit 

 of much recruiting from the -mainland for the purpose 

 of keeping up the specific types. Consequently, the 

 insects and the land-shells present a much greater 

 proportion of peculiar species namely, one half and 

 one fourth of the land-shells in the one case, and 

 one eighth of the beetles in the other. All these 

 correlations, I say, are abundantly intelligible on the 

 theory of evolution ; but who shall explain, on the 

 opposite theory, why orders of beetles and land-mol- 

 lusca should have been chosen from among all other 

 animals for such superabundant creation on oceanic 

 islands, so that in the Azores alone we find no less 

 than 32 of the one and 14 of the other ? And, in this 

 connexion, I may again allude to the peculiar species 

 of beetles in the island of Madeira. Here there are 

 an enormous number of peculiar species, though they 

 are nearly all related to, or included under the same 

 genera as, beetles on the neighbouring continent. 

 Now, as we have previously seen, no less than 

 2co of these species have lost the use of their 

 wings. Evolutionists explain this remarkable fact 

 by their general laws of degeneration under disuse, 



