Impressed by CD’s theory [of earthworm action].

Sends four samples of dust blown on board his ship from the coast of Africa, nearly 400 miles away, during four days in March 1838. Gives careful descriptions and relates the tests he made of it [see Collected papers 1: 200].

Replies to note from CL asking about views of glaciers.

Discusses David Milne’s Glen Roy paper ["On the parallel roads of Lochaber", Trans. R. Soc. Edinburgh 16 (1849): 395–418]. Rejects Milne’s theory that outlet of Glen Roy is blocked by detritus. Impressed by Milne’s discovery of an outlet at the level of the second shelf. Believes this strengthens theory that lakes were formed by glacier blocking Glen Roy. Offers arguments against glacier theory.

Criticises at length the concept of submerged continents attaching islands to the mainland in the recent period. Notes drastic alteration of geography required, the dissimilar species on opposite shores of continents, and differences between volcanic islands and mountains of mainland areas. Admits sea-bed subsidence, but not enough to engulf continents. Denies that theory can explain island flora and fauna.

Considers Edward Forbes’s idea a check on study of dissemination of species.

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.

Suggests references in Journal of researches 2d ed. in response to a query about the antiquity of man. Perplexed about S. S. Haldeman and Haldeman 1843–4. Glad to hear about A. C. Ramsay. Has received letter from H. G. Bronn.

Falconer’s letter [attacking CL, Athenæum 4 Apr 1863, pp. 459–60] is most unjust.

Regrets his letter [to Athenæum, on heterogeny] now criticised by Owen.

Comments on article by Samuel Haughton [On the form of cells made by wasps – with an appendix on the origin of species (1863)].

Mentions forthcoming reviews by Asa Gray [in Am. J. Sci.].

CD probably advised omitting mention of experiments suggesting that oxlips, cowslips, and primroses could be produced from the seed of a single plant

Asks Lyell to put a question to CD: "To what far distant origin can the configuration of the skin surface [the symmetrical but different curves] at the last points of the fingers and toes be traced?"

Sends, for signature, a statement approving change in rules of the Leopoldino Academy [Dresden] to be forwarded to CD to sign.

Hopes that Charles Lyell has enjoyed his excursion.

Thanks for the extract from the American paper.

Circular requesting recipients to sign an enclosed [missing] statement [relating to appeal for Naples Zoological Station] if they approve of it.