SEXUAL SELECTION 611 



by not being selected, or from free intercrossing, or from 

 being eliminated when transferred to the male and in any 

 way injurious to him. Thus the plumage of the female 

 would be kept constant in character. It would also be a 

 relief if we could admit that the obscure tints of both sexes 

 of many birds had been acquired and preserved for the sake 

 of protection — ^for example of the hedge-warbler or kitty- 

 wren (^Accentor modularis and Troglodytes vulgaris), with re- 

 spect to which we have no sufBcienfr evidence of the action 

 of sexual selection. We ought, however, to be cautious in 

 concluding that colors which appear to us dull are not at- 

 tractive to the females of certain species; we should bear 

 in mind such cases as that of the common house sparrow, in 

 which the male differs much from the female; but does not 

 exhibit any bright tints. No one probably will dispute that 

 many gallinaceous birds which live on the .open ground have 

 acquired their present colors, at least in part, for the sake of 

 protection. We know how well they are thus concealed; we 

 know that ptarmigans, while changing from their winter to 

 their summer plumage, both of which are protective, suffer 

 greatly from birds of prey. But can we believe that the 

 very slight differences in tints and markings between, for 

 instance, the female black grouse and red grouse serve as a 

 protection ? Are partridges, as they are now colored, better 

 protected than if they had resembled quails? Bo the slight 

 differences between the females of thei common pheasant, the 

 Japan and gold pheasants, serve as a protection, or might 

 not their plumages have been interchanged with impunity ? 

 From what Mr. Wallace has observed of the habits of cer- 

 tain gallinaceous birds in the East he thinks that such slight 

 differences are beneficial. For -myself I will only say that 

 I am not convinced. 



Formerly when 1 was inclined to lay much stress on pro- 

 tection as accounting for the duller colors of female birds, 

 it occurred to me that possibly both sexes and the young 

 might aboriginally have been equally bright-colored; but 

 that subsequently the females, from the danger incurred 



