Informs CD where, at Kew, to find Epipactis palustris.

Has never trusted Donald Beaton.

Thinks JDH is a bit hard on Asa Gray.

Bates’s letter is that of a true thinker. Asks to see JDH’s to Bates. Point raised in it is most difficult. "There is one clear line of distinction; – when many parts of structure as in woodpecker show distinct adaptation to external bodies, it is preposterous to attribute them to effect of climate etc. – but when a single point, alone, as a hooked seed, it is conceivable that it may thus have arisen." His study of orchids shows nearly all parts of the flower co-adapted for fertilisation by insects and therefore the result of natural selection. Mormodes ignea "is a prodigy of adaptation".

JDH has probably influenced Bates by pointing out applicability of CD’s views to his cases.

Is greatly puzzled by difference in effect of external conditions on individual animals and plants. Cannot conceive that climate could affect even such a single character as a hooked seed.

Does not think Huxley is right about "saltus".

He has only an uncertain memory of the placement of stamens in the [monstrous?] primrose CD asked about.

On effect of external conditions: CD thinks all variability due to changes in conditions of life because there is more variability under unnatural domestic conditions than under nature, and changed conditions affect the reproductive organs. But why one seedling out of thousands presents some new character transcends the wildest powers of conjecture.

Not shaken by "saltus" – he had examined all cases of normal structure resembling monstrosities which appear per saltum. Has fought his tendency to attribute too much to natural selection; perhaps he has too much conquered it.

Lighthearted thoughts on "the development of an Aristocracy" after a visit to Walcot Hall, Shropshire.

On CD’s point about the effect of changed conditions on the reproductive organs, JDH does not see why this is not "itself a variation, not necessarily induced by domestication, but accompanying some variety artificially selected".

Asks JDH to correct names of two species of Calanthe.

Note from Asa Gray ends "Yours cordially", so CD hopes he is forgiven.

His Catasetum paper will be read 3 Apr [Collected papers 2: 63–70].

Plants and seeds sent will be of great use, especially Lythrum, which according to J. P. E. Vaucher seems grand case of trimorphism. Asks what sort of man Vaucher is.

Identifies Calanthe masuca.

Asa Gray would not quarrel with them – "snubbing from us may have done him more good than our sympathy".

If CD means the old Vaucher, he was considered a very accurate, acute, able observer.

Both JDH’s and Bates’s letters are excellent. JDH has said all that can be said against direct effect of conditions, but CD still sticks to his own and Bates’s side. CD should have done what JDH suggests (since naturally he is pleased to attribute little to conditions) – viz., started on the fundamental principle that variation is innate and stated that afterwards, perhaps, this principle would be made explicable. Variation will show that "use and disuse" have some effect. Does not believe in perfect reversion. Demurs at JDH’s "centrifugal variation"; the doctrine of the good of diversification amply accounts for variation being centrifugal.

The wonderful mechanism of Mormodes ignea.

Gives CD advice on the illness of one of his sons [presumably Horace].

Variations are centrifugal because the chances are a million to one that identity of form once lost will return.

In the human race, we find no reversion "that would lead us to confound a man with his ancestors".

CD can add revisions since he cannot begin work on 2d German ed. of Origin until May.

Schweizerbart wants to publish translation of Orchids. Asks for woodcuts for illustrations.

Has been reading J. D. Morell’s new book on psychology [An introduction to mental philosophy, on the inductive method (1862)].

Progress of the Civil War.

Louis Pasteur’s memoir "is a very able and convincing one" ["Mémoire sur les corpuscles organisés qui existent dans l’atmosphère", Ann. Sci. Nat. (Zool.) 3d ser. 16 (1861): 5–98].

Will hope to be able to send Vanilla flowers in a day or two.

How is CD after his tremendous effect on the placid Linneans? ["Sexual forms of Catasetum", Collected papers 2: 63–70; read 3 Apr 1862.]

Cannot accept invitation at present.

Is sending a wild honeycomb from Timor.

Has several specimens illustrating dimorphism in insects that he would be happy to leave where CD could examine them.

Discusses the ant genera Formica and Atta, and the origin of the two forms of workers commonly found in the species of these genera.

Suggests CD use a tabular form for Army doctors to write their observations on, and suggests it be limited to malaria, yellow fever, and dysentery.

On Vanilla.

Asks JDH to observe whether he has both long- and short-styled form of Menyanthes

and whether he has "Saxifrages with long hairs glandular at the tip".

The Linnean Society session made him vomit all night. Fears he must give up trying to read papers or speak. "It is a horrid bore. I can do nothing like other people."

Now believes flowers of Fumariaceae must be self-fertilised.

Planning a piece on dimorphism in the Natural History Review ["On the two forms, or dimorphic condition, in the species of Primula … by Charles Darwin", n.s. 2 (1862): 235–43].

Observations on Campanula dimorphism.