Thanks ACR for paper and comments on it ["On the denudation of South Wales", Mem. Geol. Surv. G. B. 1 (1846): 297–335].

Sends copy of South America.

Discusses action of the sea.

Criticises ACR’s views on sudden elevation of mountain chains.

Thanks for THH’s essay on species [article for an American encyclopedia].

Will probably never again write on large and general subjects; will keep to easier specific ones such as insectivorous and climbing plants.

Astonished and disgusted at Klein’s evidence. No doubt there will be severe and vicious legislation against physiology. Will give evidence before Commission.

Thanks for Elementary biology [1875]. Wishes he had had a course like it.

Is coming to London. Will call on THH.

Deeply grateful for THH’s tribute to him at conferring of LL.D. at Cambridge.

Invites him to dinner on Saturday the 12th. Charles and Mrs Lyell, Edward Forbes, Richard Owen, and Thomas Bell coming also.

"Will you bring your map of S. America … and we will have a talk over it."

Thanks for evolution article; would like to know what made Lamarck "change his front" so completely.

CD’s election to Botany Section of French Academy amuses him, because he "doesn’t know the characters of a single natural order!".

Asks ACR to establish height of Moel Tryfan in Caernarvonshire; "in my notice on this hill [""Ancient glaciers of Caernarvonshire"" (1842), Collected papers 1: 163–71] I give a very much less height than others". [See also another mention of the elevation of Moel Tryfan in "On the transportal of erratic boulders" (1848), Collected papers 1: 218–27.]

About Anthony Rich, who has decided to leave his fortune to CD [and later also to make a bequest to THH]. CD’s account of what he wrote to Rich.

Has read Hume with great pleasure, but found parts very stiff reading.

George Darwin has visited Anthony Rich.

Thanks for Haeckel’s Freedom in science and teaching [1879], with preface by THH.

Enjoyed rap on knuckles THH gives Rudolf Virchow.

Suggests he write to Ernst Krause about publication of translation of Fritz Müller’s paper. FM’s view of mutual protection is quite new to CD.

Regrets he is unwilling to join [Epping Forest Field Club], but encloses a guinea to aid with their preliminary expenses.

Asks THH to advise him about a response to Samuel Butler’s attack accusing CD of dishonesty. Quotes the advice of others but will do what THH advises.

Greatly relieved by THH’s letter [advising against a reply to Samuel Butler].

Thanks for the honour conferred upon him by the Epping Forest Field Club.

Is in town and will call on Sunday morning.

Sorry he missed THH’s lecture ["The coming of age of The origin of species", Royal Institution, 9 Apr 1880]. Has read press notices and heard from his children of its great success.