My dear Henslow

Very many thanks about the Elodea,—which case interests me much. I wrote to M^r Marshall at Ely & in due time he says he will send me whatever information he can procure.—¹

Owen is indeed very spiteful. He misrepresents & alters what I say very unfairly. But I think his conduct towards Hooker most ungenerous, viz to allude to his Essay, & not to notice the magnificent results on geographical distribution.²

The Londoners says he is mad with envy because my book has been talked about: what a strange man to be envious of a naturalist like myself, immeasurably his inferior! From one conversation with him I really suspect he goes at the bottom of his hidden soul as far as I do!—

I wonder whether Sedgwick noticed in the Edinburgh Review, about the “Sacerdotal revilers”³—so the revilers are tearing each other to pieces.—   I suppose Sedgwick will be very fierce against me at the Phil. Soc.—⁴ Judging from his notice in the Spectator he will misrepresent me, but it will certainly be unintentionally done.—⁵ In a letter to me & in the above notice he talks much about my departing from the spirit of inductive philosophy.—⁶ I wish, if you ever talk on subject to him, you would ask him whether it was not allowable (& a great step) to invent the undulatory theory of Light—ie hypothetical undulations in a hypothetical substance the ether. And if this be so, why may I not invent hypothesis of natural selection (which from analogy of domestic productions, & from what we know of the struggle of existence & of the variability of organic beings, is in some very slight degree in itself probable) & try whether this hypothesis of natural selection does not explain (as I think it does) a large number of facts in geographical distribution—geological succession—classification—morphology, embryology &c. &c.— I sh^d really much like to know why such an hypothesis as the undulation of the ether may be invented, & why I may not invent (not that I did invent it, for I was led to it by studying domestic varieties) any hypothesis, such as natural selection.

Pray forgive me & my pen for running away with me & scribbling on at such length.—

My dear old Master | Yours affect^ly | C. Darwin

I can perfectly understand Sedgwick or any one saying that nat. selection does not explain large classes of facts; but that is very different from saying that I depart from right principles of scientific investigation.—