Encloses memorandum on Origin [1866]

discussing mimicry in mammals and birds,

abnormal habits shown by birds,

behaviour of cuckoos,

and analogies existing between mammals of the same geographical region.

Speculates on possible lines of development linking groups of mammals.

[CD’s notes on the verso of the letter are for his reply.]

Detailed notes on secondary sexual differences in various species of birds and mammals.

Discusses sexual and seasonal differences in the plumage of birds and coats of mammals.

Remarks upon variations in the form of the canine tooth between the sexes in mammalian groups.

Plumage of allied species of plover.

Asks CD’s help with work on unimproved domestic animals.

EB has had his pension disallowed; is coming to England.

Discusses apes and their relationships to each other. Writes particularly of the gibbon, its structure and well-developed legs giving it the ability to walk without using its hands.

Discusses the human foot and its abnormalities; notes an example of syndactylism.

Gives his observations on sexual differences in coloration of terns and ostriches.

Replies to CD’s queries regarding sexual differences in gibbons’ voices, chameleon behaviour, and the occurrence of spurs in pheasants and peahens. Discusses sexual differences in structure and habit within certain bird species.

Discusses the development of horns in antelopes. Remarks on the variation within and between the species of Cervus and on their relationship to each other.

Describes his tour of the Netherlands. Reports on some of the specimens he saw on his trip.

Discusses the coloration of hair in aged monkey

and sexual differences in bird species.

Wants to know when he may visit CD.

Has seen some curious hybrid ducks and geese of Bartlett’s. Bartlett will do experiments suggested by CD when he has time.

Sends some original observations on British ferns [not found].

Has secured a small pension and hopes to acquire a house near Kew.

Gives CD reference to case of the saiga, an antelope, fearless of man.

Reports observations by New Zealander who has seen heaps of pebbles presumably voided by Dinornis.

Discussion of origin of domestic sheep races. Some comments on the yak and the wild ancestors of the llama and alpaca.

Recommends J. Scott’s paper on crossing varieties of Verbascum.

Discusses mule canaries which show a tendency to revert to wild plumage colours.

Discusses the origin and characters of sheep breeds, particularly the merino.

Reports observations on reversion to wild type in canary mules

and lists some animals that show a unique development restricted to one side of their bodies.

Corrects some facts and gives further information on some points for the 2d ed. of Variation.

Specific distinctions among animals.

Cercopithecus of Africa contrasted with the Cebus of South America.

Notes on domestic fowls and their ancestors.

Slow growth of wild animals compared with domestic varieties.

Reports another case of syndactylism.

Has examined three races of the mouflon sheep and remarks on the extent of variation in them.