Galapagos land birds and reptiles.

No two naturalists agree on any fundamental idea [of species]. "Everything is arbitrary."

Has been with Richard Owen going over the S. American fossils.

Has worked out the non-relation between animals’ bulk and luxuriance of vegetation.

The horse once common on the Pampas. The mystery of the extinction of these animals.

Congratulations on CL’s knighthood.

CD returns a letter from Wollaston.

Although opposed to the Forbesian doctrine [of continental extension] as a general rule, CD would have no objection to its being proved in some cases. Does not think Wollaston has proved it; nor can anyone until more is known about the means of distribution of insects – but the identity of the two faunas is certainly interesting.

His health is very poor and his "everlasting species-Book" quite overwhelms him with work. It is beyond his powers, but he hopes to live to finish it.

Auguste Bravard’s discoveries magnificent.

Bravard has sent pamphlets [Observaciones geológicas (1857) and Monografia de los terrenos marinos terciarios (1858)] with strange doctrine that Pampean deposit is subaerial.

Review of Origin by Wollaston [Ann. & Mag. Nat. Hist. 3d ser. 5 (1860): 132–43] clever and misinterprets CD only in a few places.

Wallace’s MS ["Zoological geography of the Malay Archipelago", J. Proc. Linn. Soc. Lond. (Zool.) 4 (1860): 172–84] admirably good.

Henslow "will go very little way with us". "He, also, shudders at the eye!"

Baden Powell says CD’s statement about eye is conclusive.

Leonard Jenyns cannot go as far as CD, yet cannot give good reason.

Further comments on Jamieson’s theory of the formation of the roads of Glen Roy; paper by Jamieson dealing with glaciation in Scotland ["On the ice-worn rocks of Scotland", Q. J. Geol. Soc. Lond. 18 (1862): 164–84].

Comments on paper by A. C. Ramsay on the glacial formation of lakes ["On the glacial origin of certain lakes", Q. J. Geol. Soc. Lond. 18 (1862): 185–204].

Criticises remarks by John Tyndall on glacial formation of Swiss valleys.

Has just arrived in London, and would like to visit the following morning at breakfast time.

Thanks him for interesting letter from a Mr Wood on heredity in fruit-trees.

Offers condolences on the death of CL’s wife.

The coral-reef book has been invaluable [J. D. Dana, Corals and coral islands (1872); used by CD in Coral reefs, 2d ed. (1874)].

Thanks for Saturday Review.