CD’s health and his father’s death have delayed his answer. Describes J. M. Gully’s water-cure.

JDH’s Galapagos papers [Trans. Linn. Soc. Lond. 20 (1851): 163–233] have excellent discussion of geographical distribution, but why no general treatment of affinities?

CD’s views on clay-slate laminae.

Turmoil in Royal Society between naturalists and physicists.

Does not recommend that JDH publish extracts of his letters from India in the Athenæum.

CD criticises JDH’s observations on glacial deposits in Himalayas as insufficiently clear and detailed.

CD will live to finish barnacles and make a fool of himself over species.

CD thinks great dam across Yangma valley is a lateral glacial moraine.

Reports on Birmingham BAAS meeting.

Details of water-cure.

Barnacles becoming tedious; careful description shows slight differences constitute varieties, not species.

Lamination of gneiss.

Discusses books returned

and invites him to Down for a few days.

Congratulations on JDH’s safe return.

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

Thanks JDH for short sketch of botanical geography of Southern Hemisphere. Comments on his own S. American collections and observations; notes other Galapagos collections.

Queries on ratios of species to genera on southern islands. CD’s observations on distribution of Galapagos organisms, and on S. American fossils, and facts he has gathered since, lead him to conclusion that species are not immutable; "it is like confessing a murder".

C. G. Ehrenberg would like some earth from Galapagos, Tierra del Fuego, and the Falklands; wishes to hunt for Infusoria.

Thanks for information for Ehrenberg.

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.

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.

Advice to JDH on problems of printing and publishing.

Remarks on differences of species between islets of Galapagos group.

Asks JDH to forward publishing information to J. E. Gray.

Has received JDH’s infusorial specimens for Ehrenberg.

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.

Thanks for information on printing charges

and for clarifying "typical forms".

In a few days CD will go away for six weeks.

Asks if J. E. Gray has returned [printing] estimates for Zoology.

Henslow has some Galapagos plants which he forgot to forward to JDH.

Encloses letter from Ehrenberg [758] about Infusoria.

Intends to visit Kew.

Health and weather permitting, CD proposes to visit Kew.

Encloses letter from Ehrenberg [762], who wants information on deep-sea soundings from JDH’s voyage, and on isolated islands.

Encloses Ehrenberg letter, Galapagos seaweed, and specimens of Conferva.

H. Denny would like specimens of Antarctic Pediculi.