1 42 Journal of Travel and Natural History 



better than tlie gaudier ones, natural selection perpetuated their 

 offspring in greater numbers than that of the latter, and so ended in 

 producing a race of duller-coloured females. But is it so? Had it 

 been a species, and not merely the half of a species, the argument 

 would at least be consequent. But a female produces males as well 

 as females, and the result of breeding in-and-in from dull-coloured 

 females would be to dilute thecolourof the whole breed, both male 

 and female — not ]ircserve tlie male bright and turn the female dull. 

 The hereditary qualities of father and mother are no ways special to 

 the respective sexes of the offspring. In our own -species it is very 

 commonly said that the sons take after the mother, and the daugh- 

 ters after the father, which would go against Mr Wallace's theory, 

 if true ; but we believe it is not true, and that we have no reason 

 to suppose that one parent has on an average a greater share in 

 producing the physiognomy of their offspring than another. * 



The explanation of the phenomenon seems to us of a totally 

 different nature. Although the plumage of such males and females 

 as we have been speaking of is often apparently very dililerent, 

 there are grounds for believing that they are both the same, 

 only develoj)ed to different degrees, according to the amount of 

 vital action operating on each. Thus we see, in the pheasant and 

 common fowl, old hens assuming more or less of the plumage of 

 the males. In them it is obviously not a different livery, but the 

 same livery at different stages of its production. It is the same with 

 young birds, their plumage is different from that of their parents, and 

 we do not suppose that Mr Wallace would refer that to natural selec- 

 tion. It is a parallel case to the down on the chin of the boy and the 

 beard on that of the man. Why this immaturity of plumage (if 

 we may so call it) exists in some female birds and not in others 

 we do not i)retend to explain ; but it appears most probable that the 

 building of open nests was at first the normal habit with all birds, 

 and that the instinct of building them under cover, and in con- 

 cealed places by those whose bright plumage would betray them 

 in open nests was acquired by exjierience. \Ve all know that in 



* On this sul)ject see the evidence collected by Mr Darwin in his new work, 

 "Animals and Plants under Domestication," vol. ii., p. 72, which seems to us 

 to confirm the ahove conclusion, although Mr Darwin regards the facts as 

 shewing that peculiarities ajipearing in either sex "strongly tend to be in- 

 herited by the offspring of the same sex, but are often Iransniilted in a latent 

 state through theopjiosite sex." 



