Goes on the assumption that each species has one origin, is immutable, and migrates.

Disagrees with Gaudichaud[-Beaupré] that volcanic island species are polymorphous.

Some mundane genera vary, others do not (Senecio vs Gnaphalium).

John Lindley’s doctrine of longevity of trees is amazing.

Edward Forbes’s health is better.

Gives his opinion on the tropical character of fossil shells listed by CD. The shells of Navidad [Chile] are not particularly tropical.

Answers CD’s objections with botanical and geological arguments supporting the existence of an ancient post-Miocene land extending over what is now the Mediterranean and past the Azores in the Atlantic [EF’s "Atlantis" theory in "On the connexion between the distribution of the existing fauna and flora of the British Isles and the geological changes which have affected their area", Mem. Geol. Surv. G. B. 1 (1846): 336–432].