Thinks GM's Pelargonium is a case of true correlated characters. Feels secondary sexual characters are only accidental correlations; does not see the same necessity for close simultaneous development of certain characters as GM does.
Will forward a copy of his Orchids.
Down Bromley Kent
Your criticisms are profoundly interesting to me. A downright
good objection or difficulty is very nearly as interesting as a favourable
fact.— Your Review always struck me as very able (though I am not now quite so
much shaken by some remarks as I was at first) & I
have given some few of your objections in a new German edition. Very sincere thanks for the Pelargonium leaves. I
I have lately published a small Book on Orchids (small portions of which alone bear on
the general question of Species) parts of which I think would interest you. I cannot
conceive how I forgot your name when I made out a list of copies to send
away.— As I hope you will permit me to
send you a copy, I will today write to my publisher.— I sh
I assure you that I feel most sincerely grateful for your remarks & for the very kind manner in which you make them.—
Pray believe me | My dear Sir | Yours sincerely | C. Darwin
- f1 3640.f1The year is established by the relationship to the letter from George Maw, 30 June 1862.
- f2 3640.f2See letter from George Maw, 30 June 1862.
- f3 3640.f3Maw 1861. For CD's reaction to Maw's review of Origin, see Correspondence vol. 9, letters to George Maw, 13 July  and 19 July .
- f4 3640.f4In Bronn trans. 1863, p. 445, CD added a reference to Maw's objection to his statement that `the grand fact in natural history of the subordination of group under group' was explained by the theory of descent from a common ancestor and of divergence. See letter to H. G. Bronn, 25 April  and Correspondence vol. 10, Appendix VIII.
- f5 3640.f5See letter from George Maw, 30 June 1862.
- f6 3640.f6The section to which CD refers, headed `Correlation of growth' (Origin 3d ed., pp. 161--4), concludes:
We may often falsely attribute to correlation of growth structures which are common to whole groups of species, and which in truth are simply due to inheritance; for an ancient progenitor may have acquired through natural selection some one modification in structure, and, after thousands of generations, some other and independent modification; and these two modifications, having been transmitted to a whole group of descendents with diverse habits, would naturally be thought to be correlated in some necessary manner.
- f7 3640.f7At the start of his discussion in the third edition of Origin (p. 161), CD stated: `This is a very important subject, most imperfectly understood'; in the fourth edition he added: `and no doubt totally different classes of facts may be here easily confounded together: we shall presently see that simple inheritance often gives the false appearance of correlation' (Origin 4th ed., p. 170). CD gave a more detailed discussion of this subject in Variation 2: 319--38, under the heading `correlated variability'; he noted that he had formerly used `the somewhat vague expression of correlation of growth, which may be applied to many classes of facts', and sought to distinguish `correlated variability' from what in this letter he calls `accidental correlation'. See also letter from George Maw, 30 June 1862 and n. 5.
- f8 3640.f8In the chapter on reversion in Variation, CD included a discussion of what he called `latent characters', the `most obvious illustration' of which, he claimed, was `afforded by secondary sexual characters' (Variation 2: 51). He then stated:
It is well known that a large number of female birds … when old or diseased, or when operated on, partly assume the secondary male characters of their species … On the other hand, with male animals, it is notorious that the secondary sexual characters are more or less completely lost when they are subjected to castration … But characters properly confined to the female are likewise acquired … We thus see that in many, probably in all cases, the secondary characters of each sex lie dormant or latent in the opposite sex, ready to be evolved under peculiar circumstances.
- f9 3640.f9CD discussed the origin of the sexes in vertebrates in Descent 1: 207--11, arguing that `some extremely remote progenitor of the whole vertebrate kingdom appears to have been hermaphrodite or androgynous'. He also thought it `quite possible' that as each sex `gradually acquired the necessary organs proper to it, some of the successive steps or modifications were transmitted to the opposite sex', and he presented `innumerable instances of this form of transmission' (p. 208).
- f10 3640.f10See letter from George Maw, 30 June 1862, and Correspondence vol. 9, letter from George Maw, 27 August .
- f11 3640.f11Maw's name is included on the presentation list for Orchids (see Correspondence vol. 10, Appendix IV); it was probably added as an afterthought.
- f12 3640.f12The letter to John Murray has not been found.