Is studying Variation, especially Pangenesis. Reports earlier notion of Dr Robert Lee, that resemblance between husband and wife may be partly owing to her having man’s blood circulating in her during pregnancies; thus spouses most resemble each other in large families.

Thanks for letter on ALA’s qualifications for vacant chair of natural history.

Reports observations on deer which have larger left antlers than right, possibly for protection of heart.

Sends newspaper clipping about a nest of young birds, apparently hybrid offspring of a cock goldfinch and a hen green linnet.

Asks whether he may see CD before leaving England.

Instances of sexual differences in viviparous fishes, suggested by reading chapters on sexual selection [in Descent] and by Mivart’s Genesis of species.

Notes on echinoderms.

Thanks for new [6th] edition of Origin.

Is working on Echini.

The more material he gets the less easy it is to diagnose a genus or species. Has little doubt that "classification is nothing but the most arbitrary convenient tool, depending upon the material at our command at a special time".

Thanks for Expression.

Has lost a year’s work in the fire that has devastated Boston.

Is mapping coral distribution on the Tortugas reef. His observations on the Florida peninsula suggest that it was built up from the debris of animal remains and was not elevated.

Discusses the structure and formation of the Florida peninsula. Part played by marine animals in building banks on which coral can thrive.

Introduces J. P. Lesley, "the most accomplished geologist of the United States".

LA clarifies his opposition to CD’s views, which does not blind him to the great value of CD’s original researches.

Answers CD’s questions regarding sexual coloration of Amazonian fishes and the protuberances on the head of male Geophagus and Cichla during the spawning season [see Descent, pp. 520, 529].

Introduces his son Alexander; believes CD will find him "more tractable" on certain questions than LA himself is.

Has learned of death of Sarah Elizabeth Wedgwood, former proprietor of Tromer Lodge, and writes about his deceased father’s earlier attempts to purchase this property. Requests information on any future transfer of it.

Thanks for CD’s letter, and further discussion of the sale of Tromer Lodge.

Thanks for information about the property in question [Tromer Lodge, see 12842]. His father, Robert Ainslie, had protested a settlement made in an earlier transaction.

Comments on discussion of residual organs in Descent [ch. 1].

Describes his ability to contract the platysma myoides at will.

Suggests reason for loss of voluntary movement of ears in men and monkeys.