Down. | Bromley. | Kent. S.E.
May 26 1868
My dear Sir
I did not at all know of the complex changes in the plumage of chickens, & therefore did not, & cd not, put my queries definitely. From your clear & excellent letter, I shd now say that 6 weeks old wd be the best period for me; or perhaps 2 months wd be still better, as I understand there is no change after the 6 weeks until the adult plumage is acquired.1 I think the best plan wd be for you first to give me, or obtain for me, information regarding only a few breeds; & afterwards I cd judge whether to go on. I wd specify any Cuckoo sub-breed;—Pile Game, but in this case I must know how the adult hen is coloured;—Golden Spangled Polish;—Silver Sebright Bantam;—& Golden Pencilled Hamburg.
My questions refer to colour alone; I do not care about sexual differences in size or form of body, in the hackles, or in the comb or wattles; except indeed when both sexes in the adult state resemble each other to an unusual degree in some character in which the sexes of the aboriginal bird or parent wild species differ. Thus I shd have been anxious to have been informed about the period of appearance of the top knot in Polish fowls, had I not known from your account that it appears very early in life; & I am still anxious about the colour of the top knot, because in the adult state it is similarly coloured in most breeds, & dissimilar in Golden Spangled Polish.2 The Spanish hen has a very large comb, & I believe from yr book that the comb in this breed is developed at an earlier age in the male, & I suppose in the female(?), than is usual with other breeds.3
Again, if it were possible to find out any one who possessed a breed in which the hens were regularly spurred, I shd much wish to know whether the spurs were developed earlier or later in life than usual. In short I want to ascertain whether there exists any relation of any kind between the period of development of any new character, & the fact of this character being common to both sexes, or confined to one sex alone. I do not at all care about any necessary expense for a scientific purpose.4
Please cite as “DCP-LETT-6210,” in Ɛpsilon: The Charles Darwin Collection accessed on