Declines invitation to visit DN’s orchid collection. Thanks for orchids and list [of available plants]. Requests a few more spikes of Bolbophyllum, particularly of species with irritable labellum.

Thanks HWB for references.

Praises his paper ["Contributions to an insect fauna of the Amazon valley", read before Linnean Society, 21 Nov 1861, Trans. Linn. Soc. Lond. 23 (1862) : 495–566] which solves "one of the most perplexing problems which could be given to solve".

Discusses the difficulties of writing and expresses disappointment at Wallace’s book [Travels on the Amazon (1861)].

Delighted to have Quiz [Johnny Innes’ dog].

Arrangements for receiving Quiz.

Quiz arrived safely.

CD’s three sons are in bed with bad colds.

Has been in bad health and has just read HWB’s MS in the last two days. Praises the book; assured it will be successful. Offers to write to Murray. Hooker interested in conclusions on colour.

Encloses note from Murray, hoping it will be satisfactory. Murray is ready to see as much of MS as possible. Murray is considered honest but may be cautious, since HWB’s name is unknown to the public.

Reminds CWC that he offered to give information with respect to his observations on hollyhocks. Wishes he could persuade CWC to undertake experiments on the fertility of some crosses between the most distinct varieties.

Has heard of mules of canary and other finches breeding occasionally, but it is rare, and there is hardly one authenticated case of two such mules breeding together.

Sixteen of the household at Down are sick with influenza.

Writes that [Murray’s] terms are very favourable; has never heard of such terms offered for a first work. HWB can depend on fact that Murray is pleased with it [The naturalist on the river Amazons].

Invitation to visit; Hooker will be present. Gives directions to Down. Also plans to invite John Lubbock over for an evening.

Quiz has had to be killed because he became vicious.

Horace Darwin strangely ill.

Thanks for letter and "valuable" extracts.

If S. American Carabi differ more from other species than do those from other distant locations (e.g., Siberia, Europe, etc.), CD agrees that difference would be too great to have occurred in the recent glacial age; CD also rejects independent origin. Plants seem to migrate more readily than animals. HWB should not underrate length of glacial period; CD also believes they will be driven to an older glacial period.

Sorry about news of British Museum – hopeless to contend against anyone supported by Owen.

CD dearly wishes HWB could find a situation in which he could give time to science.

Referring to conversation with Lyell, CD is certain that there was a Miocene glacial period.

Compliments HWB on the mimetic display at the British Museum. Those at the Museum readily accepted HWB’s "doctrine".

Was shown genital organs of closely allied Chrysomelidae.

Albert Günther is candidate for position at Museum.

Asks DO to identify a plant grown from earth adhering to the foot of a woodcock.

Asks for news of HWB and his book.

There has been sickness in CD’s family; one of the boys [and Emma] had scarlet fever.

Has had a letter from Edwin Brown of Burton who is working on classification of Carabi.

Thanks for last note. Assures HWB that all writers have problems similar to his.

Plans to inquire at Linnean Society for HWB’s paper.

His family, including Mrs Darwin and Leonard, are now well.

Thanks LB for copy of his Aus Natur und Wissenschaft [1862]. Responds to LB’s comment [on Origin].

Just finished HWB’s paper ["Contributions to an insect fauna of the Amazon valley", Trans. Linn. Soc. Lond. 23 (1862): 495–566], one of the most remarkable he has ever read. Found mimetic cases and connection of facts marvellous. Finds equally important the facts on variation and segregation of complete and semi-complete species. Questions whether insect mimicry is not due to small size and defencelessness. Criticises title of paper. Mentions that Wallace will appreciate it.

[Apparently in reply to question in missing portion of 3825.] A written agreement is unnecessary, but a letter stating terms would prevent misundertanding. He will attempt to have a review of HWB’s paper published.