Summary

Asks about CL’s new book [Travels in North America (1845)].

Discusses views of A. D. d’Orbigny on elevation.

Mentions reading W. H. Prescott [History of the conquest of Mexico (1843)].

Summary

Thanks Horner for his letter [about Volcanic islands].

Discusses craters of elevation with respect to the views of Leopold von Buch and Élie de Beaumont. Compares Lyell’s views to those of continental geologists. Mentions reading A. D. d’Orbigny [Voyage dans l’Amérique méridionale (1835–47)].

Encloses note from Emma to Mrs Horner, inviting the Horners to visit Down.

Summary

To avoid possible misundertanding of his letter [2654] of that morning, CD wishes to make clear that he did not wish to imply that BP’s essay and the Vestiges of creation were in the same class. The more he thinks of it the more difficult he feels it would be to give a fair account of the authors who have maintained the modification of species. CD finds that he referred to BP’s views in the preface to his larger work [Natural selection], which was replaced by the Origin.

Summary

Seeks permission to make another visit to Addiscombe [Military College] to see again the model of St Helena. He needs to correct proportion of some geological sections in his Geology [see Volcanic islands, ch. 4].

Summary

Asks MEL to translate page of paper by Sven Lovén ["Ny art af Cirripedia", Ofvers. K. Vetensk. Acad. Forh. Stockholm 1 (1844): 192–4]. CD is "dreadfully interested" in the barnacles [Alepas squalicola] described.

Hopes Charles Lyell’s "craters of Denudation" prosper.

Summary

Discusses CL’s refutation of CD’s concept of "craters of elevation" and CL’s new concept of "craters of denudation". Mentions examples of such craters. Admits that his own concept of these craters was unsatisfactory. Urges CL to publish article ["On craters of denudation", Q. J. Geol. Soc. Lond. 6 (1850): 207–34].

Summary

Much obliged for note from Alexander von Keyserling. Geologist going one inch with CD more important than naturalist going two or three.

Summary

JDH’s arguments against transmutation: 1. Plants do not show the confusion he would expect; 2. Under clearly similar physical conditions we do not find same species.

JDH’s argument against migration: commonality of alpine species. Believes migration opposes facts of botanical distribution in Van Diemen’s Land and New Zealand; prefers continental extension theory.

Summary

Prepared to think world infinitely old, but not that life originated with a single cell. Questions whether geological evidence supports gradual progress in organisation. HW thought scientific opinion during Vestiges debate was against this hypothesis. Argues that presence of same senses in lower animals and vertebrates does not imply descent; assumes resemblance is due to living in same world and thus having organs for the same purposes. Wants CD to know how others may see these questions.

Summary

Congratulations on JDH’s safe return.

Henslow has sent CD’s S. American plants to JDH for examination.

Summary

CD has heard from Lyell that JM is inclined to publish a second edition of Journal of researches. His agreement with Henry Colburn leaves CD free to publish with anyone. Will have no further relations with Colburn. Discusses details of proposed revisions.

Summary

Island floras; relationships with mainland. Ranges of species in mundane genera.

Galapagos plants one-third done.

Summary

Sends a copy of the paper [with A. R. Wallace, "On the tendency of species to form varieties" (1858), Collected papers 2: 3–19] about which his correspondent asked; CD’s parts were written years ago and not intended for publication; he gave permission for publication of the extracts. Wallace’s paper seems to him excellent.

Summary

Thanks for H. C. Watson’s interesting letter. Disagrees with him on intermediate varieties.

CD has read latest numbers of JDH’s The botany of the Antarctic voyage [pt I, Flora Antarctica (1844–7)]; notes several sentences against "us Transmutationists".

Summary

Troubled by JDH’s connection between Antarctic island flora and Fuegia, which CD sees as part of a general relation to southern circumpolar flora. Encloses list [not found] of plants from Tristan d’Acunha.

Summary

Thanks CD for his patience and good-nature; does not want a controversial correspondence but wishes to reply to matters in CD’s letter, and does.

Summary

JDH wants papers at once. CD sends Wallace’s paper and CD’s abstract of his letter to Asa Gray. Sends [species] sketch of 1844 with JDH’s notes to assure JDH he had read it.

Summary

Asks WBC if he will examine a specimen of calcareous rock.

Summary

To make his monograph on cirripedes complete, would appreciate a specimen of Alepas squalicola, which CD is sure is a new genus.

Summary

Proportion of molluscan species to genera in various periods. The difficulty of determining species increases with the number of species per genus. Identifying species within a genus is most difficult in that period in which the genus shows its greatest development.