Comments on an article in Edinburgh Review [by David Brewster, 67 (1838): 271–308] on Comte’s Philosophie positive.
Discusses falsity of Élie de Beaumont’s views of contemporaneous parallel lines of elevation and subsidence.
Owen’s views of relationship of reptiles to birds.
On "question of species" CD has filled notebook after notebook with facts, "which begin to group themselves clearly under sub-laws".