Summary

Origin of Antarctic brash ice.

Further on case of Lycopodium: does JDH know any genera of plants whose species are variable in one continent but not in another? Discussion on variations between floras as regards species richness, and factors affecting geographical distribution. On species, CD expects "that I shall be able to show even to sound naturalists that there are two sides to the question of the immutability of species; – that facts can be viewed and grouped under the notion of allied species having descended from common stocks". Mentions books and papers for and against species mutability. CD believes past absurd ideas arose from no one’s having approached subject on side of variation under domestication.

Would like to see Clarke’s paper

and would welcome visit from JDH.

Summary

Thanks for pleasant stay at Down.

Remarks on boulders found on southern islands.

Describes the alpine character of the Andes flora and relays information on other mountain floras.

Quotes instances of seeds that retained their vitality after being carried by ocean currents.

Sends notes on the comparative floras of New Zealand, Australia, and west coast of South America.

Encloses a copy of part of a letter from George Gardner in Ceylon concerning the European character of the mountain flora.

Summary

Declines to undertake to have AM’s journal published but recommends possible publishers in England.

Expresses scepticism about AM’s glacier theory. Emphasises role of floating ice instead. Mentions article by William Hopkins on movement of glaciers.

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

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

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

Asks that in the event of his death, Emma should have the sketch of his species theory edited and published. Suggests possible editors, among them Lyell, Edward Forbes, and J. D. Hooker. [CD annotation on cover: "Hooker by far best man to edit my species volume Aug 1854".]

Summary

Differences in variability of species within a single genus. Further observations on Lycopodium.

Interested in Humboldt’s river with different floras on opposite banks, and other unexplained cases of very local distributions.

Summary

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

Comments on typical forms.

Preparing first part of Galapagos plants for printing.

Summary

Questions on JDH’s sketch comparing floras of Australia, New Zealand, and western S. America; wishes to know botanical relations between other southern islands. Botanico-geographical discussions and comments on books sent by JDH.

Summary

Sends four packets of lice and suggests writing to Dr A. Smith, "the S. African traveller", for assistance.

Summary

Sends a specimen of rusty wheat from the banks of the Plata.

Asks for bits of peat he collected

and a bit of the paint used by Fuegians to colour themselves.

He will send these to C. G. Ehrenberg for analysis.

Summary

Would like to visit on the weekend of 7–8 December.

Differences in floras of St Helena and Ascension.

Summary

Inquires about the habits of a litter of foxhounds whose sire was particularly good at recovering the scent in paths or roads.

Summary

[Notes on conversations with J. D. Hooker.] Geographical distribution; diffusion and distribution of species. Island and mountain floras; means of migration (high-roads, icebergs).

Summary

Mexican specimen of laminated obsidian.

Comments on Forbes’s publication comparing lava streams and glaciers. Mentions ice-action theories of a young German.

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

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

Acknowledges note and parcel for Ehrenberg.

Considers why different areas have different numbers of species. Gives an example opposing JDH’s view that paucity of species results from vicissitudes of climate. CD has concluded that species are most numerous in areas that have most often been divided, isolated from, and then reunited with, other areas. Cannot give detailed reasons but believes that "isolation is the chief concomitant or cause of the appearance of new forms".

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.