Requests information on the standard of beauty of savages and on whether the female has any influence in selecting a male.

CD has questions related to colour differences in the sexes of butterflies, especially in relation to HWB’s paper ["On variation in sexes of Argynnis diana", Proc. Entomol. Soc. Philadelphia 4 (1865): 204–7].

Mentions that his MS on Lepidoptera [for Descent] is longer than he intended and the information is four-fifths owed to HWB.

Thanks HWB for answering questions.

The MS on Lepidoptera is almost finished and he is glad HWB will read it; he is fearful of mistakes, not being familiar with the subject.

Lists specimens he wants from Mr Janson, emphasising that he always wants male and female.

He extends an invitation for a Sunday in early June.

Explains why he has declined writing a review for Messrs Appleton.

Thanks for assistance. He will write fully to Wallace tomorrow.

Orders five works on the Sandwich Islands from the Royal Geographical Society Library for his investigation of infanticide and population trends there.

Encloses extract [missing] on a caterpillar.

Mentions William Buckler’s magnificent drawings of caterpillars [The larvae of the British butterflies and moths, Ray Soc. (1886–91)], but doubts Buckler will lend them for any Darwinian purpose. John Hellins has a portion of drawings and is more liberal.

F. Galton and others suggest that he go in for Fellowship [of Royal Society]. Asks that CD propose him. If he is unable to do so HWB will not be hurt to wait another year.

Sends his paper ["Insect fauna of the Amazon valley", Trans. R. Entomol. Soc. Lond. 2d ser. 5 (1861): 223–8, 335–61].

Points out three areas of interest arising from the study of the species of Papilio: the derivation of the fauna, the variability of the species, and the permanence of local varieties.

Discusses J. S. Baly’s views on specific differences in reproductive organs [Catalogue of the Hispidae in the collection of the British Museum (1858)].

Discusses specific varieties, especially geographic varieties.

Comments on the effects of the glacial age on the tropics.

Sexual selection.

Mention of Volucella.

Discusses the mimicry of the Volucella flies, and the bees and wasps they mimic. Compares it with the different object of mimicry in butterflies.

Refers to incompleteness of Cuthbert Collingwood’s paper [? "On homophormism, or organic representative forms", Proc. Liverpool Lit. & Philos. Soc. 14 (1860): 181–216].

Thanks CD for help in selecting a publisher for his book [The naturalist on the river Amazons (1863)].

Furnishes CD with more information on Volucella and gives him references relating to this and butterfly colourings. States that colours are not necessarily related to resting-places but rather an endowment to enable them to withstand adverse conditions.

Sends CD ch. 2 of his book [The naturalist on the river Amazons] for suggestions, having accepted CD’s recommendations concerning ch. 1.

Effects of climate on dress in ch. 1 similar to, but independent of, notions expressed by CD in his Journal of researches [p. 381].

On geology, book deals with distribution and theory of deltas of the Amazon.

Grieved to hear of CD’s illness; begs him not to give moment’s thought to his MS until health has returned.

Plans to exhibit mimetic butterflies at Linnean Society.

Thanks CD for returned MS and letter with its good opinion. Asks CD to write to Murray.

Accepts CD’s invitation.

Discusses insects of south temperate S. America and New Zealand, especially with respect to the distribution and origin of Chilean Carabi, and has sent for a German monograph to learn about the eleven species he has found.

He refers to Chilean poverty in butterflies; scanty New Zealand insect fauna.

An analysis of south temperate insects is desirable, but the small English collections make him afraid to undertake it.

Miocene glacial period a remarkable discovery; if it is true, enlargement of Tertiary period necessary.

Received German monograph on Chilean Carabi that does not answer where isolated species came from.

HWB finds genital modifications of Chrysomela strong support for the theory.

Thanks for copy of Orchids.