My dear Hooker

Many thanks for your splendid long letter.¹ But first for business.— Please look carefully at enclosed spec. of Dicentra thalictriformis² & throw away: when plant was young I concluded certainly that tendrils were axial or modified branches, which Mohl says is case with some Fumariaceæ.—³ You looked at them here & agreed.—⁴ But now plant is old, what I thought was a branch with two leaves & ending in tendril, looks like a gigantic leaf, with 2 compound leaflets & terminal part converted into tendril. For I see buds in fork between supposed branch & main stem.— Pray look carefully, you know I am profoundly ignorant, & save me from a horrid mistake.—⁵

And now I must say a few words on the several & all interesting points in your letter.

Have you Ch. Martins on Sahara & can you lend it?⁶

I am quite delighted with what you say about H. Spencer’s book:⁷ when I finish each number I say to myself what an awfully clever fellow he is, but when I ask myself what I have learnt, it is just nothing. In the last number,, however, he hits a blot in the “Origin”⁸ but not in my rough M.S. viz no allusion to what the old physiologists call the nisus formativus.—⁹ I do not admire so much his style, & I think invariably 2 or 3 pages might be condensed into one.—

When I wrote to you I had not read Ramsay,¹⁰—how capitally it is written— it seems that there is nothing for style like a man’s dander being put up.— I think I agree largely with you about denudation—but the rocky lake-basin theory is the part which interests me at present.— It seems impossible to know how much to attribute ice,—running water, & sea.— I did not suppose that Ramsay would deny that mountains had been thrown up irregularly & that the depressions would become valleys.— The grandest valleys I ever saw were at Tahiti & here, I do not believe, ice had done anything—anyhow there were no erratics— I said in my S. American Geology that rivers deepen & the sea widens valleys,¹¹ & I am inclined largely to stick to this, adding ice to water.— I am sorry to hear that Tyndall has grown dogmatic.¹² H. Wedgwood¹³ was saying the other day that T.’s writings & speaking gave him the idea of intense conceit; I hope it is not so, for he is a grand man of science.

About the Red Cowslip, I said that it ought not to be called a species, unless it run wild, solely as the most severe test of sufficient constancy of character.—¹⁴

When I suggested Wallace for R. medal, I must confess I had obscure glimmering that it w^d be difficult to state claims.¹⁵ His Amazon Book is nothing;¹⁶ his Nat. Selection would, I suppose, rather go against him with Royal Soc^y.¹⁷ I do not know whether his admirable paper before Linn. Soc^y. is published.¹⁸ He wrote one good paper on Geograph. Distribution¹⁹ & he has published Geographical papers;²⁰ but I fear it would be impossible yet to make out good case. Talking of Geograph. Distrib. I have had a Prospectus & letter from Andrew Murray, asking me for suggestions!²¹ I think this almost shows he is not fit for subject, as he gives me no idea what his book will be, excepting that the printed paper shows that all animals & all plants of all groups are to be treated of!! Do you know anything of his knowledge.—

In about a fortnight I shall have finished, except concluding chapter, my Book on “Variation under Domestication”;²² but then I have got to go over the whole again, & this will take me very many months; I am able to work about 2 hours daily.

Thanks about Stanhopea, but I have at last set a capsule:²³ my Stanhopeas flowered gorgeously, but I cannot make Acroperas & Gongoras flower, which I much wish for, as I believe Stanhopea has shown me the dodge for Acroperas which formerly so confounded me & John Scott.²⁴ I grieve to hear about M^r M’Nab & him—²⁵

Farewell   forgive this awesomely long letter. Yours affectionately, | C. Darwin

I cannot buy at Veitchs,²⁶ Coryanthes or Cycnoches,²⁷ if you could propagate plants of both, or either, I sh^d. be pleased,—not that I suppose I shall ever publish my new matter on orchids.—