84 Journal of Travel and Natural History 



the female more gay and often larger. I am not, however, aware 

 that these two anomalies had ever been supposed to stand to each 

 other in the relation of cause and effect, till I adduced them in 

 support of my views of the general theory of " Mimicry." * Yet it 

 is undoubtedly the fact, that in the best known cases in which the 

 female bird is more conspicuously coloured than the male, it is 

 either positively ascertained that the latter performs the duties of 

 incubation, or there are good reasons for believing such to be the 

 case. The most satisfactory example is that of the gray phalarope 

 (Phalaropus fulicarius, Linn.), the sexes of which are alike in winter, 

 while in summer the female instead of the male takes on a gay and 

 conspicuous nuptial plumage ; but the male performs the duties of 

 incubation, sitting upon the eggs, which are laid upon the bare 

 ground. 



In the dotterell (Eudromias morinellus) the female is larger and 

 more brightly coloured than the male, and 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, and 

 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 shewn to have an interdependent relation 

 to each other on the simple princijjle of the need of greater pro- 

 tection to that parent which performs the duties of incubation. t 



* "Mimicry and other Protective Resemblances among Animals." — IVcst- 

 rn'mster Rcvinv, July 1867. 



+ In his " Origin of Species," fourth edition, p. 241, Mr. Darvvin recognises 

 the necessity for protection as sometimes being a cause of the obscure colours of 

 female birds ; but he does not seem to consider it so very important an agent in 



