Suggests that, in some birds, plumage of males is less colourful than that of females; the reason is that the males perform the duties of incubation [see Descent 2: 204 n.].

Answers JVC’s questions about the rock-thrush, the tortoise-shell cat, and the logger-headed duck.

Position as Curator allows no time for experiment.

Describes plans for vast new layout of Calcutta Botanic Garden according to natural orders.

Himalayan and Scottish plants are doing well.

Hopes to experiment on temperate plants in tropics, to test CD’s views of migration during glacial periods.

Sends observations on acclimatisation of English cultivated plants.

Leersia CD sent are growing and fertile.

Would like Friedrich Anton Wilhelm Miquel’s photograph, but JDH should give CD’s address to FAWM.

Thanks for letter and glad Frances Harriet Hooker goes on well.

Do not send St Helena earth.

Thanks for the information about the male plumage. [See 5374.] Will look to the papers in Ibis to which AN has referred him. He finds AN’s theory captivating.

Describes progress in preparation of third German edition of the Origin. Asks about use of photograph for edition.

Two queries on teeth: 1. Is there evidence of inherited peculiarities in milk teeth?

2. Are male incisors longer than female?

Encloses letter written a week ago. Letter and enclosure speculate on origins of human races in relation to geological and political changes, according to a theory of progressive development.

Was sorry CD wrote so little on man in Origin.

Hopes JM’s friend will give his judgment [on Variation] soon; and urges JM to come to a decision about publishing. CD believes it will have "a fair sale".

JM will publish [Variation] "coute qui coute", paying CD half the profits.

Thinks he can count on 500 purchases of what he calls the "Pièces Justificatives" of the Origin and will print 750 copies.

His literary friend found it "difficult of digestion".

On final instalment of "Insular floras" [Gard. Chron. (1867): 75]; rejoices at extent of their agreement.

Some criticisms of JDH’s position on geographical affinities, and volcanic islands.

CD agrees to JM’s proposal of half-profits. Thinks it a mistake to print only 750 copies. The agreement on half-profit is for first edition only. CD estimates his book at a higher value than JM does.

First portion of Variation MS has been set up. Murray will not decide on number to be printed until he has read a good portion. The agreement applies only to the first edition.

Is convinced his chapter on man [for Variation] will excite plenty of attention and abuse, which he supposes is as good as praise for selling a book.

Statement of sales of U. S. edition of Origin.

Wants to know whether Variation is published and how the other book [CD’s proposed volume on variation in nature] is going.

Thanks for information about rudimentary organs. Asks about rudimentary character of human hair and panniculus carnosus.

Replies to Queries on expression based on observations of the Kaffir and Fingoe tribes in South Africa.

Thanks for CD’s letter inquiring about capsules produced by the Maxillaria with larger pods [see 5331]. Gives descriptions of Maxillaria and of the other Vandeae.

Describes Oncidium flexuosum.

Tells of botanical results of recent excursion to the German colony Theresopolis. Brought home fine collection of living orchids.

Will be glad to see her on 4th.

Thinks Hensleigh is getting better, very slowly.