To Asa Gray 15 April 1
Down. | Bromley. | Kent. S.E.
My dear Gray
How good you have been to take so much trouble about the Expression-queries.— I wish I had thought earlier of having them printed, for in that case I might have sent a dozen to each of my few correspondents, as it is I can think of no one to send them to, so do not want any more.2
By the way I have just thought of Thwaites in Ceylon & will send him a couple.3
I have been lately getting up & looking over my old notes on Expression, & fear that I shall not make so much of my hobby-horse, as I thought I could: nevertheless it seems to me a curious subject, which has been strangely neglected.4
I have seen no one for months (but Hooker I rejoice to say will be here next Saturday)5 & have no news.— I am plodding on heavily correcting, & trying to make an atrociously bad style a little better, my book “on the Variation of Animals & Plants under Domestication”: I would offer to send you clean sheets, but I do not think you would care to receive them. There is not much about plants, & what there is, is almost all mere compilation; it will be a fearfully big book in two vols. & I shall be the next 5 or 6 months merely correcting the press: it is enough to make one curse one’s fate in being an author.—6
I manage to get a little amusement by some of my experiments.— I have proved that the trimorphic species of Oxalis behaves in exactly the same complicated manner in regard to their fertilisation as Lythrum.—7 I am going on with my trials of the growth of plants raised from self-fertilised & crossed seeds, & begin now to suspect that the wonderful difference in growth & conststitutional vigour occurs only with exotic plants which have been raised by seed during many generations in England, but which are not properly visited by insects & so have been rarely crossed.—8
I have just heard of a case which has interested me hugely, & which I am inclined to believe is true; namely that by cutting the tubers of differently coloured potatoes through the eye, & joining them, you can make a hybrid or mongrel. I am repeating this experiment on a large scale, for it seems to me, if true, a wonderful physiological fact.9
Here is a long prose all about my own doings.
Farewell with many thanks | Yours most sincerely | Ch Darwin
Thanks AG for his trouble about expression queries; wishes he had thought earlier of having them printed.
Is "plodding on" correcting Variation
and getting "a little amusement" from plant experiments. Oxalis is trimorphic like Lythrum.
Is continuing his experiments on seedling vigour.
Has heard hybrid potatoes can be produced by joining halves of different tubers.