the child. A point just occurs to me (though it does not at present
concern me) about birds' nests. Have you read Wallace's recent articles?
(441/2. A full discussion of Mr. Wallace's views is given in "Descent of
Man," Edition I., Volume II., Chapter XV. Briefly, Mr. Wallace's point is
that the dull colour of the female bird is protective by rendering her
inconspicuous during incubation. Thus the relatively bright colour of the
male would not simply depend on sexual selection, but also on the hen being
"saved, through Natural Selection, from acquiring the conspicuous colours
of the male" (loc. cit., page 155).) I always distrust myself when I
differ from him; but I cannot admit that birds learn to make their nests
from having seen them whilst young. I must think it as true an instinct as
that which leads a caterpillar to suspend its cocoon in a particular
manner. Have you had any experience of birds hatched under a foster-mother
making their nests in the proper manner? I cannot thank you enough for all
your kindness.


LETTER 442. TO A.R. WALLACE.

(442/1. Dr. Clifford Allbutt's view probably had reference to the fact
that the sperm-cell goes, or is carried, to the germ-cell, never vice
versa. In this letter Darwin gives the reason for the "law" referred to.
Mr. A.R. Wallace has been good enough to give us the following note:--"It
was at this time that my paper on 'Protective Resemblance' first appeared
in the 'Westminster Review,' in which I adduced the greater, or rather, the
more continuous, importance of the female (in the lower animals) for the
race, and my 'Theory of Birds' Nests' ('Journal of Travel and Natural
History,' No. 2) in which I applied this to the usually dull colours of
female butterflies and birds. It is to these articles as well as to my
letters that Darwin chiefly refers."--Note by Mr. Wallace, May 27th, 1902.)