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.

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.