Criticises chapter on good effect of crossing in Variation: (1) does not accept that inbreeding alone results in degeneracy; (2) good effects of crossing exaggerated; (3) denies deleterious effects of close marriage in humans.

Sends specimens of Passiflora and seeds for T. H. Farrer [letter enclosed with 7188].

Sends CD some notes on the habits of the "American Blight Bird" in New Zealand.

Notes the differences in haemoglobin between species; this proves, to WP, that natural selection does not act only on morphological development.

Remarks on the differences and similarities in the effects of prussic acid on different groups of animals.

Questions CD on his early education and influences.

Ask whether CD would like to subscribe again to National Education League. Describes the League’s goals.

Encloses his letter to GJ [6885], which was returned.

Comments on effects of prussic acid on different individuals of the same species and other physiological research by WP.

Provides information about his studies in Edinburgh and Cambridge and qualifications he had for Beagle voyage. Describes influence of R. E. Grant and J. S. Henslow.

Invites WDF to visit.

Describes activities of his children.

Moritz Wagner is going to attack selection theory in his new book on his travels in America [Naturwissenschaftliche Reisen im tropischen Amerika (1870)].

K. G. Semper may attack CD’s theory of coral islands.

Has read the notes on Rond [Round] Island which he owes to JDH. What an enigma its flora and fauna present, especially the problem of monocotyledons! Asks JDH’s opinion.

A new book on St Helena confirms CD’s observations.

Thanks for sending him a hybrid.

"I have received a very large box full of beautiful tea from Russia yesterday … my life is as regular & monotonous as a clock.

I make sure, but wofully slow progress, with my new book."

Thanks JO for his The Andes and the Amazon.

Is sorry he has failed to get any information on the horse’s tooth.

Congratulations [on election to Parliament]; hopes science will not suffer because of politics.

Previously wrote inquiring about savages and suicide, but JL need not hurry to answer.

Forwards part of a note [by Mrs L. Agassiz] asking AG to tell CD that Agassiz has never been able to secure one of the fishes sitting on eggs.

In P.S., AG adds, "Agassiz evidently regrets having abused you in former times."

Suicide is rare among savages [see Descent 1: 94].

Transformism explains rudimentary organs, and teratology, which are otherwise inexplicable.

Looking forward to publication of Descent

and CD’s expected book on "Variation in nature" [see Variation 1: 4].

Describes his brother Alexander’s discovery of male of Bonellia, a striking example of dimorphism. Encloses a plate with notes on his brother’s work.

The difficulty his wife, Sofya Kovalevsky, has had as a woman in being admitted to Berlin University. Kirchow [Gustav Robert Kirchhoff], at Heidelberg, has taken an interest in her.