Summary

Advice to JDH on problems of printing and publishing.

Remarks on differences of species between islets of Galapagos group.

Summary

Answer to CD’s query on genera and species ranges.

Comments on typical forms.

Preparing first part of Galapagos plants for printing.

Summary

Asks whether salt and carbonate of lime (in the form of seashells) would act upon each other if slightly moistened and left in great quantities together. The question occurs from CD’s having found in Peru a great bed of recent shells that were mixed with salt, decayed and corroded "in a singular manner". Mentions, as relevant to the value of seashells as manure, that they are dissolved more rapidly by water than any other form of carbonate of lime.

Summary

Has just completed Volcanic islands.

Sends queries on Galapagos flora in particular and island floras in general; also on relationship of wide-ranging species to wide-ranging genera.

Summary

Affinity of Galapagos with nearest Pacific islands. Relationship between ranges of species in time and space. Comparison of Malden Island and Galapagos plants. Affinities of Oceania plants with continental floras.

Summary

Can hardly believe he made a mistake in specimens sent to HD. Recopies numbers in case he transposed them. [Has to do with lice taken from a specimen of aperea and put into spirits during Beagle voyage.]

Summary

Thanks WBC for offer to examine specimen and for offer of slices of shells, but has no achromatic microscope.

Summary

Thanks for JDH’s interesting details about the Galapagos.

Clarification of CD’s query about the relationship between the range of a genus and the ranges of its constituent species.

Summary

Discusses microscopic examination of rock specimens taken from Pampas deposit and from Chilean tuff. Says he finds organic remains only in the tuff.

Summary

Discusses the connection between climate and vegetation. Believes that an equable climate is unfavourable to increase of species either by importation or modification of existing forms; illustrates his view with reference to particular floras. Hopes to acquire facts to support CD’s idea that isolation is important in producing new forms. Considers the floras of islands some of which do have distinctive species but others of which do not. Agrees that the wide ranges of cryptogams are a consequence of their means of dispersal. Asks for references to works on original creation and species mutability in order to get the best notions of "the (mad) theories of some men from Lamarck’s twaddle upwards".

Summary

Thanks for CD’s comments on "sketch".

Lengthy discussion of geographical distribution and island floras.

Has been "delighted with" [Robert Chambers’] Vestiges [of creation (1844)].

Galapagos flora work goes on well.

Summary

Discusses a specimen of Mexican obsidian with an unusual laminated structure.

Summary

Sends calculations of angles of elevation [of sea-bottom, for South America?].

Swale has sent Lady Willoughby’s diary, which EAD will forward to CD.

Summary

Urgently needs a Spanish map of the Cordilleras of central Chile near St Jago [Santiago].

Summary

Asks whether LJ can throw light on this subject: "What are the checks and what the periods of life by which the increase of any given species is limited?" CD has been driven to conclude that species are mutable; allied species are co-descendants from common stocks.

Summary

Mentions his Plutonic view of earth history.

Cites Lyell’s opinions on loess.

CD doubts contemporaneousness of extinct great animals with ice period.

Cites applicability of Forbes’s theory of glacier structure to structure of volcanic obsidian.

CD is falling astern in the geological race for knowledge.

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

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)].