Has heard that CL has spoken to John Murray about publication [of Origin]. Encloses prospective title-page. Asks whether he ought to tell John Murray about unorthodoxy of the book.

CD is grateful to CL for his help in arranging with Murray for publication [of Origin]. Sorry Murray objects to term "abstract" in title, but will defer to him and CL.

Extended discussion of their respective difficulties with the definition and status of species and with the extent to which the theory of transmutation may be applied.

Has rediscovered S. S. Haldeman’s 1844 paper defending the transmutation theory with great skill.

Asks for reference to Geoffroy Saint-Hilaire’s first enunciation of the progressive development and transmutation theory.

Discusses S. S. Haldeman’s paper ["Enumeration of the recent freshwater Mollusca", Boston J. Nat. Hist. 4 (1844): 468–84].

Centres of species origin.

Describes his corrections of Origin.

Thanks CL for copy of his paper ["Structure of lavas", Philos. Trans. R. Soc. Lond. 148 (1858): 703–86].

Promises him a copy of Origin.

CL’s research on flint tools.

Promises to send proof-sheets of Origin. Discusses his view of species.

Ill health of himself and his family.

Thanks CL for his favourable remarks to the Geological Section of the BAAS concerning the forthcoming publication of the Origin. Hopes CL will accept his view of species.

Comments on CL’s paper ["On the occurrence of works of human art in post-Pliocene deposits", Rep. BAAS 29 (1859): 93–5].

Discusses text of Origin.

Compares Eocene and modern climates.

Mentions Hooker’s view of his geographical [distribution] chapters.

Asks CL’s opinion of his statements on distribution during "glacial and preceding warmer periods".

Mentions chapters on geological record and embryology.

Is sending off last proof-sheets of Origin.

Asks CL’s opinion of final chapter. Mentions difficulties of his argument.

Is too unwell to start for Ilkley.

Murray’s printing of 1250 copies seems too large to CD.

Praises the Origin: a "splendid case of close reasoning".

Objects to CD’s having ignored Lamarck and Geoffroy Saint-Hilaire.

Thinks CD should omit mentioning problem of explaining the eye at the beginning of chapter 14. Suggests rewording several passages.

Thinks want of peculiar birds in Madeira a difficulty, considering presence of them in Galapagos.

Has always felt that the case of man and his races is one and the same with animals and plants.

Response to Origin. Praise for summary of chapter 10 and chapter 11.

The dissimilarity of African and American species is ‘necessary result of “Creation” adapting new species to the pre-existing ones. Granting this unknown & if you please miraculous power acting’.

C. T. Gaudin writes of Oswald Heer’s finding many species common between Miocene floras of Iceland and Switzerland. Interesting for CD’s migration theory.

CL’s comments on Origin. Mentions corrections to last chapter suggested by CL.

Comments on lack of peculiar bird species on Madeira and Bermuda. Emphasises importance of American types in Galapagos.

Denies necessity of continued creation of primitive "Monads".

Denies need for new powers and any principle of improvement.

Discusses gradations of intellectual powers.

Adaptive inferiority and extinction of groups of species and genera.

Asserts that climate is less important than the struggle with other organisms.

Suggests an experiment involving primroses and cowslips.

The chapter on hybridisation.

Rudimentary organs.

Gives opinion of Lamarck’s work.

Comments on CL’s letters.

Discusses foreign animals naturalised in Australia and elsewhere.

Affirms man’s capacity to survive in Eocene climate.

Comments on American types.

Denies necessity for "continued intervention of creative power".

Wishes CD would enlarge on the doctrines of [Pyotr Simon] Pallas about the various races of dogs having come from several distinct wild species or sub-species.

Suggests organisms have a latent principle of improvement which is brought out by selection or breeding.

Discusses P. S. Pallas’ theory of origin of domestic dog breeds. CD believes domestic dogs descended from more than one aboriginal wild species but ultimately "we believe all canine species have descended from one parent and the only question is whether the whole or only part of difference in our domestic breeds has arisen since man domesticated them".

Races of man offer great difficulty. The doctrine of Pallas and Agassiz that there are several species "does not help us" in the least.

Hopes Henry Holland will not review Origin.

CD’s and CL’s difference on "principle of improvement" and "power of adaptation" is profound. Improvement in breeds of cattle requires neither. Urges him to reread first four chapters of Origin carefully. Natural selection is not to be contrasted with "improvement": every step involves improvement in relation to the conditions of life. There is no need for a "principle" to intervene.

Since dogs have same gestation period as the wolf it is likely that the wolf is the ancestral wild species, if it is just one species.

CD’s belief that domestic dogs are descended from several distinct aboriginal species seems to contradict views on sterility of hybrids and variation in Origin. If domestic varieties came from hybrids of wild species it will be impossible to trace ancestry. Opponents will exploit these problems.

Further discussion of origin of domestic dog breeds.

Effects of crossing separate races.

Comments on rate of artificial and natural selection.

The origin of pigeon breeds.

Questions CD’s view in Origin that domestic dogs are not descended from a single stock. Occasional crossings of domestic stock with wild species could explain cases of reversion towards wild specific forms. CD’s views on hybridity do not then have to be contradicted in constructing an ancestral stock.

Comments on pp. 201, 211, and 218 [of Origin].

Thanks CL for his decision to accept CD’s "doctrine of modification" [in Elements of geology, 6th ed. (1865)]. Believes it "morally impossible that investigators of truth, like you and Hooker, can be wholly wrong". Does not think CL’s decision will injure his works.

Thinks CL overrates importance of multiple origin of dogs.

Mentions sending copy of Origin to Herschel. Asks CL about Herschel’s reaction.