FAUSA OF REMOTE rKOVINCES, 



293 



citrrents exhibit a great wealth of different species even in 

 adjacent islands, while those species which are easily trans- 

 ported have a much wider range, combined with a greater 

 constancy of character, than the species of the former group. 



It might perhaps be inferred from the foregoing remarks 

 that it is my view that in every case when faunas widely sepa- 

 rated by distance exhibit a certain resemblance or affinity of 

 species, one and the same influence, i.e. the action of constant 

 marine currents, must be regarded as the cause of that correla- 

 tion. But I think I hardly need guard against such a mis- 

 apprehension ; a brief account of the most interesting cases of 

 this kind will suffice for my purpose. 



FlO. 7e,~Temmicephcda chilensis, Blancliard, -wliich lives, absolutely identical in species 

 (no difference being perceptible in either tlie external or anatomical character), in 

 Chili, Java, and the Philippines. Parasitical on fresh-watsr crabs bilouging to quite 

 difEereut genera. 



Giinther has shown that the tortoises of the Mauritius"* 

 are very nearly related to those of the Galapagos, which, Ipng 

 near South America, are almost the antipodes of the island in 

 the Indian Ocean. The characteristic species of Bulimus (a 

 land mollusc) in South America have theij- nearest allies, not in 

 North America nor in the West Indies, but in New Caledonia 

 and the Feejee Islands, as I can attest from my own minute 

 investigation of such animals. The extinct birds of Madagascar 

 show a near relationship to those of New Zealand ; many fresh- 

 water fish of New Zealand are identical or very nearly allied 

 with those of Chili ; Temnocephala chilensis, a small parasite 



