xvii REPTILES 407 



and insects have a desert character, and are not more brilliantly 

 coloured than those from southern Patagonia ; we may, there- 

 fore, 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 Temminckii from Chile.^ Of sea- turtle I 

 believe there is 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, 

 considering how well suited for themJiiJSLtern^eraJt^^ 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 archipelago. Mauritius offers an 

 apparent exception, where I saw the Rana Mascariensis in 

 abundance : this frog is said now to inhabit the Seychelles, 

 Madagascar, and Bourbon ; but on the other hand, Du Bois, 

 in his voyage in 1669, states that there were no reptiles in 

 Bourbon except tortoises ; and the Officier du Roi asserts that 

 before 1768 it had been attempted, without success, 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. 



1 This is stated by Dr. Giinther [Zoolog. Sor. Jan. 24th, 1S59) to be a peculiar 

 species, not known to inhabit any other country. 



2 Voyage mix Qnatre Iks d' Afriqiie. With respect to the Sandwich Islands, see 

 Tyerman and Bennett's Journal, vol. i. p. 434. For Mauritius, 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. J ago in the Cape de 

 Verds. There are none at St. Helena. 



