Origin is finished.

Asks for names of foreign speculative naturalists.

Hopes THH will think he is on right road despite errors.

Murray has sold out Origin; wants a new edition immediately.

Asks THH to check whether Geoffroy de St Hilaire is correct [form of name].

Would be grateful for THH’s impressions on the truth of natural selection.

THH’s letter about the Origin makes CD feel like a Catholic who has received extreme unction. Can now sing nunc dimittis. Had determined to abide by judgment of Lyell, Hooker, and THH.

Problem of how variations arise at all troubles him also.

Rejoices over THH’s lecture ["On species and races, and their origin", 10 Feb 1860, Not. Proc. R. Inst. G. B. 3 (1858–62): 195–200] to be given at Royal Institution. Offers pigeon illustrations.

Adam Sedgwick has sent a "slashing" letter [2548] about Origin.

Sends references for materials useful for THH’s lecture.

Breeding and crossing. Pigeon fanciers.

Responses to Origin: A. C. Ramsay, Charles Kingsley, Quatrefages de Bréau.

Thanks for THH’s review of Origin in Macmillan’s Magazine ["Time and life: Mr Darwin’s Origin of Species", 1 (1859–60): 142–8]. Reception of natural selection will depend on whether it explains the recognised laws in the several fields of natural history.

Domestic variation.

Sends enclosure [unspecified].

Reminds THH to mention [German] translation [of Origin] when he writes to R. A. von Kölliker.

Sends anecdotes and drawings of pigeons for Royal Institution lecture. Offers parts on hybridisation and pigeons from his MS (if THH has patience to read them).

Has heard George Busk is converted.

Will bring materials for Royal Institution lecture [when he comes to London].

Plans to bring out separate detailed volumes [on his theory], starting with domestic variation.

Sends MS on pigeons for THH’s lecture at Royal Institution.

Henry Holland and others have attacked his reasoning from analogy to one primordial created form – by which CD means only that we know nothing of how life originated. The reasoning seems probable to him, so he has kept it in.

Delighted with Times review [26 Dec 1859]. Puzzled by author, suspects THH, but publication in Times makes it unlikely. Sorry for Owen.

THH comments on G. A. Brullé’s paper ["Researches upon the transformations of the appendages of the Articulata", Ann. & Mag. Nat. Hist. 13 (1844): 484–6].

On classification and possibilities of a scientific morphology and zoology. CD’s "pedigree business" is important for physiology but has nothing to do with pure zoology any more than human pedigree has to do with the census. Zoological classification is a census of the animal world.

K. E. von Baer’s view of the air bladder of fishes.

Serial homologies in the Mollusca. Gives instances of repetition of homological parts in Radiata.

Has just finished Origin. CD has demonstrated a true cause for the production of species.

CD has loaded himself with unnecessary difficulty in adopting natura non facit saltum.