To Herbert Spencer   31 October [1873]¹

Dear Spencer

I have not a word to say against your view, & indeed I think it must hold good, though one would like to have some evidence of a daily movement becoming fixed in one direction & inherited.—² With respect to assymmetry in the flowers themselves, I remain contented from all that I have seen, with adaptation to visits of insects.— There is, however, another factor which it is likely enough may have come into play, viz the protection of the anthers & pollen from the injurious effects of rain: I think so because several flowers inhabiting rainy countries as A. Kerner has lately shown, bend their heads down during rainy weather—³ If this movement became fixed & inherited, we sh^d have, according to your view, a species with permanently dependent flowers.

I was glad to receive today an advertisement of your book. I have been wonderfully interested by the articles in the Contemporary.⁴ Those were splendid hits about the P. of Wales & Gladstone.⁵ I never before read a good defence of Toryism.⁶ In one place, (but I cannot for the life of me recollect where or what it exactly was) I thought that you would have profited by my principle (i.e. if you do not reject it) given in my Descent of Man, that new characters which appear late in life are those which are transmitted to the same sex alone. I have advanced some pretty strong evidence, & the principle is of great importance in relation to secondary sexual likenesses.⁷ I have applied it to man and woman, & possibly it was here that I thought that you would have profited by the doctrine.— I fear this note will be almost illegible, but I am very tired.

Yours vy sincerely | (signed) Ch. Darwin