Returns ARW's notes. He will work up subject much better than CD.
Apologises for the note of illiberality in his letter regarding ARW's work on the colouring and other sexual differences in mammals.
Discusses laws of inheritance based on sexual selection.
He questions the extent of applicability of principles of protection and sexual selection to lower animal forms, though Ernst Haeckel has shown how protection may account for transparency and absence of colour in lower oceanic animals.
Down. | Bromley. | Kent. S.E.
My dear Wallace
The offer of your valuable notes is most generous, but it w
You seem already to have well investigated the subject. I confess on receiving yr note
that I felt rather flat at my recent work being almost thrown away, but I did not intend
to shew this feeling. As a proof how little advance I had made
on the subject, I may mention that though I had been collecting facts on the colouring,
& other sexual differences in mammals, your explanation with respect
to the females had not occurred to me. I am surprized at my own stupidity, but I have
long recognized how much clearer & deeper your insight into matters is than
mine. I do not know how far you have attended to the laws of inheritance, so what
follows may be obvious to you. I have begun my discussion on sexual selection by shewing
that new characters often appear in one sex & are transmitted to that sex alone,
& that from some unknown cause such characters apparently appear oftener in the
male than in the female. Secondly characters may be developed & be confined to
the male, & long afterwards be transferred to the
With respect to the females of deer not having horns, I presume it is to save the loss of organized matter.
On the other hand Häckel has recently well shewn that the transparency & absence of colour in the lower oceanic animals, belonging to the most different classes, may be well accounted for on the principle of protection.
Some time or other I sh
Forgive me, if you can, for a touch of illiberality about y
- f1 5528.f1The year is established by the relationship between this letter and the letter from A. R. Wallace, 1 May 1867.
- f2 5528.f2See letter from A. R. Wallace, 1 May 1867 and n. 3.
- f3 5528.f3See letter from A. R. Wallace, 26 April , and letter to A. R. Wallace, 29 April .
- f4 5528.f4See Variation 2: 71--5; see also Descent 1: 282--5.
- f5 5528.f5See Origin 4th ed., pp. 240--1.
- f6 5528.f6See Variation 1: 256. The information was from Bechstein 1789--95.
- f7 5528.f7CD's views on horns, or the lack of them, in female deer, were developed further during his work on Descent, the projected work on sexual selection, particularly among humans, that he had been discussing with Wallace. In Descent 2: 243 he wrote: `No doubt with female deer the development during each recurrent season of great branching horns … would have been a great waste of vital power, on the admission that they were of no use to the females.'
- f8 5528.f8See Descent 1: 322.
- f9 5528.f9CD refers to Ernst Haeckel's Generelle Morphologie (Haeckel 1866), 1: 241--3. This section is annotated in the copy in the Darwin Library--CUL (see Marginalia 1: 355--7). See Descent 1: 323.
- f10 5528.f10See letter from A. R. Wallace, 1 May 1867 and nn. 2 and 3.