Speculates about cause of inclination in unusual columns of lava. Suggests CL check with William Hopkins about sliding movements in viscid matter.

Comments on CL’s expedition to Madeira.

Urges CD to publish his theory with small part of data.

Corrects names of land shells on list of shells picked up at Down.

Discusses transport of Ancylus from one river-bed to another by water-beetle.

"I hear that when you & Hooker & Huxley & Wollaston got together you made light of all Species & grew more & more unorthodox."

Mentions discussion of old Atlantis by Oswald Heer.

Comments on Helix and Nanina.

Mentions beetle discovered with small bag of eggs of water-spider under wing.

Madeira evidence favours single species birth-place theory.

Discusses possibility of publishing a sketch of his views.

Comments on CL’s letter [1862].

Mentions various geological topics.

Asks to borrow publication by Heer.

Mentions flight of Colymbetes over ocean.

Recalls visit by Wollaston.

Notes views of Hooker and Huxley on species.

Mentions ability of ducks to transport plant seeds.

No summary available.

Condemns theory of Edward Forbes and others that many islands were formerly connected to South America by now submerged continents.

CD forgets an author [CD himself in Coral reefs] "who, by means of atolls, contrived to submerge archipelagoes (or continents?), the mountains of which must originally have differed from each other in height 8,000 (or 10,000?) feet".

CL begins to think that all continents and oceans are chiefly post-Eocene, but he admits that it is questionable how far one is at liberty to call up continents "to convey a Helix from the United States to Europe in Miocene or Pliocene periods".

Will CD explain why the land and marine shells of Porto Santo and Madeira differ while the plants so nearly agree?

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.

To cast doubt on CD’s view that volcanic action is associated with elevation of land, CL suggests that local oscillations in strata underlying volcanoes could also explain how active volcanoes have uplifted fossil deposits of marine shells. Overall he is more inclined to believe that recent volcanoes belong to areas of subsidence rather than of elevation.

Discusses theory of submerged continental extensions. Objects that if it is applied to one island, it must be applied to all. Admits that some volcanoes may have been associated with subsidence, in contrast to his former view. Cites evidence from S. American Cordillera. Doubts that elevation associated with volcanoes is merely local, and that great ocean areas are necessarily sinking.

Says he will make his essay [on species] as complete as possible and will discuss CL’s Principles.

Thanks CL for loan of [Matthew Fontaine?] Maury’s map.

Discusses possibility of submerged continental extension including Madeira, Canaries, and Azores.

Mentions icebergs as carriers of European plants.

Hooker’s work on Antarctic flora.

Comments on coolness of tropics in glacial period and consequent migrations. Hooker’s views on this.

Illnesses of Mrs Horner and Emma Darwin.

Death of Sarah Elizabeth Wedgwood.

Mentions work on his "Big Book" [Natural selection].

Remarks on J. A. H. de Bosquet’s discovery of a Chthamalus in the Chalk.