I83SJ BIRDS. 277 



original paucity of birds in this archipelago, one species had been 

 taken and modified for different ends. In a like manner it might be 

 fancied that a bird originally a buzzard, had been induced here to 

 undertake the office of the carrion-feeding Polybori of the American 

 continent. 



Of waders and water-birds I was able to get only eleven kinds, and 

 of these only three (including a rail confined to the damp summits of 

 the islands) are new species. Considering the wandering habits of 

 the gulls, I was surprised to find that the species inhabiting these 

 islands is peculiar, but allied to one from the southern parts of South 

 America. The far greater peculiarity of the land-birds, namely, 

 twenty-five out of twenty-six being new species or at least new races, 

 compared with the waders and web-footed birds, is in accordance with 

 the greater range which these latter orders have in all parts of the 

 world. We shall hereafter see this law of aquatic forms, whether 

 marine or fresh-water, being less peculiar at any given point of the 

 earth's surface than the terrestrial forms of the same classes, strikingly 

 illustrated in the shells, and in a lesser degree in the insects of this 

 archipelago. 



Two of the waders are rather smaller than the same species brought 

 from other places ; the swallow is also smaller, though it is doubtful 

 whether or not it is distinct from its analogue. The two owls, the 

 two tyrant fly-catchers (Pyrocephalus), and the dove, are also smaller 

 than the analogous but distinct species, to which they are most nearly 

 related ; on the other hand, the gull is rather larger. The two owls, 

 the swallow, all three species of mocking-thrush, the dove in its 

 separate colours, though not in its whole plumage, the Totanus, and 

 the gull, are likewise duskier coloured than their analogous species ; 

 and in the case of the mocking-thrush, and Totanus, than any other 

 species of the two genera. With the exception of a wren with a fine 

 yellow breast, and of a tyrant fly-catcher with a scarlet tuft and breast, 

 none of the birds are brilliantly coloured, as might have been expected 

 in an equatorial district. Hence it would appear probable, that the 

 same causes which here make the immigrants of some species smaller, 

 make most of the peculiar Galapageian species also smaller, as well as 

 very generally more dusky coloured. All the plants have a wretched, 

 weedy appearance, and I did not see one beautiful flower. The insects, 

 again, are small sized and dull coloured, and, as Mr. Waterhouse 

 informs me, there is nothing in their general appearance 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 g^udy 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 



