Impressed by Fritz Müller’s argument for natural selection in air-breathing apparatus of crustaceans ["The Darwinian hypothesis supported by observations on Crustacea", Ann. & Mag. Nat. Hist. 3d ser. 15 (1865): 410–16].

Plans to visit CD.

Thanks for THH’s willingness to read Pangenesis MS. Thinks some such view will have to be adopted but it overthrows, in an uncomfortable manner, ordinary development.

Thanks JH for compliments on his work [History of the Mathematical Theory of Probability]. Suggests changes in the Wilhelm Struve probability problem.

Requests CD’s photograph.