252 , A THEORY OF BIBBS' NESTS. 



here, also, it is almost certain that the latter sits upon 

 the eggs. The Turnices of India also, have the female 

 larger and often more brightly coloured ; and Mr. 

 Jerdon states, in his " Birds of India," that the natives 

 report, that, during the breeding season, the females 

 desert their eggs and associate in flocks, while the 

 males are employed in hatching the eggs. In the few 

 other cases in which the females are more brightly 

 coloured, the habits are not accurately known. The 

 case of the Ostriches and Emeus will occur to many as 

 a difficulty, for here the male incubates, but is not less 

 conspicuous than the female ; but there are two reasons 

 why the case does not apply ; the birds are too large 

 to derive any safety from concealment, from enemies 

 which would devour the eggs they can defend them- 

 selves by force, while to escape from their personal foes 

 they trust to speed. 



We find, therefore, that a very large mass of facts 

 relating to the sexual colouration and the mode of 

 nidification of birds, including some of the most 

 extraordinary anomalies to be found in their natural 

 history, can be shown to have an interdependent re- 

 lation to each other, on the simple principle of the need 

 of greater protection to that parent which performs the 

 duties of incubation. Considering the very imperfect 

 knowledge we possess of the .habits of most extra- 

 European birds, the exceptions to the prevalent rule 

 are few, and generally occur in isolated species or in 

 small groups ; while several apparent exceptions can 

 be shown to be really confirmations of the law. 



