Dear Sir

I am much obliged for the copy of your long letter, which I have read with great interest, as well as your articles in Nature.¹ The subject seems to me as important and interesting as it is difficult. I am at present out of health & working very hard on a very different subject; so that I cannot give your remarks the attention which they deserve. I will, however, keep your letter for a future time. It makes it clearer to me than it ever was before, how an organ or part, which has already begun from any cause to decrease, will go on decreasing through mere so called spontaneous variability with intercrossing; for under such circumstances it is very unlikely that there should be variation in the direction of encrease beyond the average size; & no reason why there should not be variations of decrease. I think this expresses your view.² I had intended this summer to subject plants to severe conditions & observe the effects on variation; but the work would be very laborious, yet I am incline⁠⟨⁠d⁠⟩⁠ to think that it will be hereaf⁠⟨⁠ter⁠⟩⁠ worth the labour.

With my best thanks | I remain, dear Sir, | yours faithfully | Ch. Darwin