My dear Sir
I thank you most sincerely for sending me your Memoir.—2 I have read it with the liveliest interest, as is natural for me; but you have the art of making subjects, which might be dry, run easily. I have been fairly astonished at the amount of individual variability in the oaks.3 I never saw before the subject in any department of nature worked out so carefully. I noted with delight case of achenia &c &c.—4 What labour it must have cost you! You spoke in one letter of advancing years; but I am very sure that no one would have suspected that you felt this.—5 I have been interested with every part; though I am so unfortunate as to differ from most of my contemporaries in thinking the the vast continental extensions of Forbes, Heer & others are not only advanced without sufficient evidence, but are opposed to much weighty evidence.—6
You refer to my work in the kindest & most generous spirit.— I am fully satisfied at the length in belief to which you go, & not at all surprised at the prudent reservations which you make.7 I remember well how many years it cost me to go round from old beliefs. It is encouraging to me to observe that everyone who has gone an inch with me; after a period goes a few more inches or even feet.— But the great point, as it seems to me, is to give up the immutability of specific forms; as long as they are thought immutable, there can be no real progress in ‘epiontology”.8 It matters very little to anyone except myself, whether I am a little more or less wrong on this or that point; in fact I am sure to be proved wrong in many points. But the subject will have, I am convinced, a grand future.—
Considering that Birds are the most isolated group in the animal kingdom, what a splendid case is this Solenhofen bird-creature with its long tail & fingers to its wings!9 I have lately been daily & hourly using & quoting your Geograph. Bot., in my book on “Variation under Domestication”.10
with cordial thanks & sincere respect | I remain Dear Sir | Yours very faithfully | Ch. Darwin
Please cite as “DCP-LETT-3917,” in Ɛpsilon: The Charles Darwin Collection accessed on