Chap. XV. COLOUR AND NIDIFICATION. 171 



that looking to the birds of the world, a large majority 

 of the species in which the females are conspicuously 

 coloured (and in this case the males with rare exceptions 

 are equally conspicuous), build concealed nests for the 

 sake of protection. Mr. Wallace enumerates ^^ a long 

 series of groups in which this rule holds good ; but it 

 will suffice here to give, as instances, the more familiar 

 groups of kingfishers, toucans, trogons, puff-birds (Capi- 

 tonidse), plaintain-eaters (Musophagse), woodpeckers, and 

 parrots. Mr. Wallace believes that in these groups, 

 as the males gradually acquired through sexual selec- 

 tion their brilliant colours, these were transferred to 

 the females and were not eliminated by natural selec- 

 tion, owing to the protection which they already enjoyed 

 from their manner of nidification. According to this 

 view, their present manner of nesting was acquired 

 before their present colours. But it seems to me 

 much more probable that in most cases as the females 

 were gradually rendered more and more brilliant from 

 partaking of the colours of the male, they were gradu- 

 ally led to change their instincts (supposing that they 

 originally built open nests), and to seek protection by 

 building domed or concealed nests. No one who studies, 

 for instance, Audubon's account of the differences in the 

 nests of the same species in the Northern and Southern 

 United States,^^ will feel any great difficulty in admit- 

 ting that birds, either by a change (in the strict sense 

 of the word) of their habits, or through the natural 

 selection of so-called spontaneous- variations of in- 

 stinct, might readily be led to modify their manner of 



nesting. 



" ' Jom-nal of Travel,' edited by A. Murray, vol. i. p. 78. 



^^ See many statements in the ' Ornithological Biography.' See, also, 

 some curious observations on the nests of Italian birds by Eugenio 

 Bettoni, in the ' Atti della Societa Italiana,' vol. xi. 1869, p. 487. 



