Invitation to dine at the Darwins’ with J. S. Henslow.

Sends Origin as testimony to great benefit CD derived from AdeC’s works on distribution.

Has read the Origin several times. His position is like Asa Gray’s: he wishes to believe in descent, but proofs of natural selection are lacking.

Looks forward to CD’s promised large book.

Thanks for Primula paper [Collected papers 2: 45–63]. Did CD sow the seeds of his crosses? One would like to know whether the two forms reappear at random.

Is pleased that AdeC is interested in the Primula case ["Dimorphic condition of Primula", Collected papers 2: 45–63]. Is pursuing analogous experiments on other plants and on seedlings raised from the unions.

CD’s "large work" progresses slowly owing to ill health and his work on Orchids.

CD is not surprised that AdeC is unwilling to admit natural selection – "the subject hardly admits of direct proof or evidence. It will be believed in only by those who think that it connects & partly explains several large classes of facts".

Hopes AdeC will publish on Quercus

and rejoices that he intends to return to the study of geographical distribution. No one can claim to have read AdeC’s truly great work on that subject [Géographie botanique (1855)] with more care than CD.

Praises Orchids.

He has finished his work on Quercus.

H. Lecoq has worked on hybridism,

and P. Duchartre on orchid polymorphism.

Thanks AdeC for his memoir ["Étude sur l’espèce", Ann. Sci. Nat. (Bot.) 4th ser. 18 (1862): 59–110].

CD astonished at the amount of variability in the oaks.

CD differs from most contemporaries in thinking that the vast continental extensions of Forbes, Heer, and others are not only advanced without sufficient evidence but are opposed to much weighty evidence.

AdeC’s comment on CD’s work [Origin] is generous.

CD is satisfied at the length AdeC goes with him and is not surprised at his prudent reservations. He remembers how many years it took him to change his old beliefs. The great point is to give up immutability. So long as species are thought immutable there can be no progress in "epiontology" [see ML 1: 234 n.]. CD is sure to be proved wrong in many points but the subject will have "a grand future".

CD thinks that he believes in as much migration as AdeC, only he does not believe nearly so much in continental extensions. CD also believes more in modification in form though he suspects the difference is not so great.

Thanks AdeC for information on melons, oranges,

and Swiss lake-habitation discoveries.

CD is almost tired of his book on variation under domestication, for his knowledge is insufficient to treat the plant part well, but he has done so much that he will finish it.

Asks AdeC to observe two species of Lythrum to see whether they are dimorphic as stated by Vaucher. CD can find no trace of this in dried specimens he has examined; "if either species present any difference in length of pistil and stamens, it is most likely that three forms should be presented".

In London for the Botanical Congress; regrets missing CD.

Lyell and CD have mistaken H. Lecoq’s position on glaciers. He has not denied the possibility of a glacial period, only that decreased temperature is needed for their extension.

Recommends F. J. Ruprecht on vegetable detritus in the black earth chernozem of Russia.

Thanks for Variation.

Offers notes and reflections on Variation.

Not convinced by Pangenesis, particularly its dependence on the Cytisus [graft hybrid] examples [ch. 27 and ch. 11].

What a book could be written on the application of natural history to man! Gives examples of inheritance in man.

Thanks AdeC for his long letter full of interesting facts, which will be of great use if a new edition [of Variation] is demanded.

As for when CD will publish on variation in a state of nature: he has had the MS almost ready for several years but Variation fatigued him so much

that "I determined to amuse myself by publishing a short essay on the Descent of Man".

AdeC will have plenty of time to publish his views. Asks permission to quote AdeC on a case of inheritance of scalp-muscles [see Descent 1: 20].

Hooker has expressed a view, similar to AdeC’s, "that morals & politics would be very interesting if discussed like any branch of Natural History".

Agrees with AdeC on acclimatisation

and on graft-hybrids.

CD is repeating Hildebrand’s method in producing graft-hybrid potatoes.

As for Pangenesis, very few people approve of it though it has some enthusiastic friends and CD has much faith in its vitality.

Corrects himself on Robinia pseud-acacia: its spines are stipules, which explains hereditary fixity.

AdeC’s observations on movement of scalp muscles.

Thanks AdeC for correcting an error about thorns, which CD might have quoted.

CD will be cautious in regard to the muscles of the scalp. [Descent 1: 20].

His health has failed again "in the usual manner" and he has been ordered to do no work.

Repeats how interested and pleased he was by AdeC’s last long, remarkable letter.

Reports on the differences of growth and development of plants of three species grown at Geneva from seed collected at different localities. Forwards seed for CD to plant and observe differences in development.

Carl Linsseer has published a memoir on the times of flowering, foliation, etc. of diverse species in different parts of Europe [Mem. Acad. Imp. Sci. St.-Pétersbourg 7th ser. 11 no. 7 (1868)] and concludes that the northern forms are more forward and that this is hereditary. AdeC’s experiments carried out on annuals, show only the effects of heredity; probably the direct action of physical conditions affects development, at least in perennial species.

Thanks AdeC for his interesting letter [6915]. The experiment strikes CD as a very valuable one. CD has forwarded the letter to Hooker, who is glad to make the trial. CD will have many experiments in progress next spring but he will open the packet of seeds and if they are numerous, will try a few himself.

Thanks for Descent.

Reveals that it is his own family that has the movable scalp.

The Franco-Prussian war has held up the publication of the 17th and last volume of the Prodromus.

Thanks for AdeC’s Histoire des sciences [1873].

Sends a copy of Expression.

His health keeps him weak; he dreads grappling with the fearful subject of variation [in nature]

so he is working up some observations in botanical physiology to publish with his old papers on climbing plants.

Thanks AdeC for great pleasure his new book [Histoire des sciences (1873)] has given him. Comments on several of the essays.

When AdeC backs up Asa Gray in saying all instincts are congenital habits, CD must protest.

Asks several questions about butterflies of the Alps discussed on p. 322 [of Histoire].

Thanks for Expression, which has made him wonder whether his shyness in public until the age of 55 resulted from fear of subjecting his face to ridicule.

Criticises F. Galton’s Hereditary genius [1869] for neglecting environmental influence.