In regard to one of these papers Mr. Darwin wrote (May 13th, 1869): "Your
verification of Wallace's suggestion seems to me to amount to quite a
discovery."); it seems to me much the best plan; therefore, I will not
forward your letter to Mr. Wallace. I was much in the Zoological Gardens
during my month in London, and picked up what scraps of knowledge I could.
Without my having mentioned your most interesting observations on the
display of the Fringillidae (439/2. "Descent of Man" (1901), page 738.),
Mr. Bartlett told me how the Gold Pheasant erects his collar and turns from
side to side, displaying it to the hen. He has offered to give me notes on
the display of all Gallinaceae with which he is acquainted; but he is so
busy a man that I rather doubt whether he will ever do so.

I received about a week ago a remarkably kind letter from your brother, and
I am sorry to hear that he suffers much in health. He gave me some fine
facts about a Dun Hen Carrier which would never pair with a bird of any
other colour. He told me, also, of some one at Lewes who paints his dog!
and will inquire about it. By the way, Mr. Trimen tells me that as a boy
he used to paint butterflies, and that they long haunted the same place,
but he made no further observations on them. As far as colour is
concerned, I see I shall have to trust to mere inference from the males
displaying their plumage, and other analogous facts. I shall get no direct
evidence of the preference of the hens. Mr. Hewitt, of Birmingham, tells
me that the common hen prefers a salacious cock, but is quite indifferent
to colour.

Will you consider and kindly give me your opinion on the two following
points. Do very vigorous and well-nourished hens receive the male earlier
in the spring than weaker or poorer hens? I suppose that they do.
Secondly, do you suppose that the birds which pair first in the season have
any advantage in rearing numerous and healthy offspring over those which