336 THE 'ORIGIN OF SPECIES.* [i860. 



the amount of the denudation) [with the] antiquity of St. 

 Helena, and its age agrees with the peculiarity of the flora. 

 With respect to bats at New Zealand (N.B. There are two or 

 three European bats in Madeira, and I think in the Canary 

 Islands) not having given rise to a group of non-volant bats, 

 it is, now you put the case, surprising ; more especially as 

 the genus of bats in New Zealand is very peculiar, and there- 

 fore has probably been long introduced, and they now speak 

 of Cretacean fossils there. But the first necessary step has to 

 be shown, namely, of a bat taking to feed on the ground, or 

 anyhow, and anywhere, except in the air. I am bound to 

 confess I do know one single such fact, viz. of an Indian species 

 killing frogs. Observe, that in my wretched Polar Bear case, 

 I do show the first step by which conversion into a whale 

 "would be easy," "would offer no difficulty"!! So with seals, 

 I know of no fact showing any the least incipient variation of 

 seals feeding on the shore. Moreover, seals wander much ; 

 I searched in vain, and could not find one case of any species 

 of seal confined to any islands. And hence wanderers would 

 be apt to cross with individuals undergoing any change on an 

 island, as in the case of land birds of Madeira and Bermuda. 

 The same remark applies even to bats, as they frequently 

 come to Bermuda from the mainland, though about 600 miles 

 distant. With respect to the Amblyrhynchus of the Gala- 

 pagos, one may infer as probable, from marine habits being 

 so rare with Saurians, and from the terrestrial species being 

 confined to a few central islets, that its progenitor first arrived 

 at the Galapagos ; from what country it is impossible to say, 

 as its affinity I believe is not very clear to any known species. 

 The offspring of the terrestrial species was probably rendered 

 marine. Now in this case I do not pretend I can show 

 variation in habits ; but we have in the terrestrial species a 

 vegetable feeder (in itself a rather unusual circumstance), 

 largely on .lichens, and it would not be a great change for 

 its offspring to feed first on littoral algae and then on sub- 



