366 GALAPAGOS ARCHIPELAGO. [CHAP. xvn. 



which would have led him to imagine that they had come from 

 under the equator.* The birds, plants, and insects have a desert 

 character, and are not more brilliantly coloured than those from 

 southern Patagonia; we may, therefore, conclude that the usual 

 gaudy colouring of the intertropical productions, is not related 

 either to the heat or light of those zones, but to some other cause, 

 perhaps to the conditions of existence being generally favourable 

 to life. 



We will now turn to the order of reptiles, which gives the most 

 striking character to the zoology of these islands. The species are 

 not numerous, but the numbers of individuals of each species are 

 extraordinarily great. There is one small lizard belonging to a 

 South American genus, and two species (and probably more) of the 

 Amblyrhynchus a genus confined to the Galapagos Islands. There 

 is one snake which is numerous ; it is identical, as I am informed 

 by M. Bibron, with the Psammophis Teruminckii from Chile. f Of 

 sea-turtle I believe there are more than one species ; and of tortoises 

 there are, as we shall presently show, two or three species or races. 

 Of toads and frogs there are none : I was surprised at this, con- 

 sidering how well suited for them the temperate and damp upper 

 woods appeared to be. It recalled to my mind the remark made by 

 Bory St. Vincent,:]: namely, that none of this family are found on 

 any of the volcanic islands in the great oceans. As far as I can 

 ascertain from various works, this seems to hold good throughout 

 the Pacific, and even in the large islands of the Sandwich archi- 



* The progress of research has shown that some of these birds, which 

 were then thought to be confined to the islands, occur on the American 

 continent. The eminent ornithologist, Mr. Sclater, informs me that this 

 is Hie case with the Strix punctatissima and Pyrocephalus nanus; and 

 probably with the Otus Galapagocusis and Zenaida Galapagoensis : so 

 that the number of endemic birds is reduced to twenty-three, or probably 

 to twenty-one. Mr. Sclater thinks that one or two of these endemic 

 forms should be ranked rather as varieties than species, which always 

 seemed to me probable. 



t This is stated by Dr. Giinther (Zoolog. Soc., Jan. 24th, 1859) to be a 

 peculiar species, not known to inhabit any other country. 



% Voyage aux Quatre lies d'Afrique. With respect to the Sandwich 

 Islands, see Tyermau and Bennett's Journal, vol. i. p. 434. For Mauri- 

 tius, see Voyage par un Officier, etc., part i., p. 170. There are no frogs 

 in the Canary Islands (Webb et Berthelot, Hist. Nat. des lies Canaries). 

 I saw none at St. Jago in the Cape de Verds. There are none at 

 St. Helena. 



