Regrets delay in sending pamphlets for JDD.

Thanks him for information concerning cirripedes.

Sends thanks to Charles Pickering for information about plant distribution.

Discusses boring species of cirripedes.

Believes Harry D. S. Goodsir mistaken about parasites on Balanus ["Observations on organs of generation in Crustacea", Edinburgh New Philos. J. 36 (1843–4): 183–6]. In fact parasites are the males of the species.

Discusses attachment of antennae in larvae of cirripedes.

Asks for information about how parasitic cirripedes are attached to host.

Thanks for note of 13 May and tracings of the "curious Bopyrid".

Is astonished at amount of work JDD does and frightened it will cause ill-health, such as CD has experienced.

Thanks him for letter and Balanus specimen.

Acasta is curious; may be a new genus.

Is sending copy [of Fossil Cirripedia 1]. Correcting proofs [of Living Cirripedia 1].

Mentions comment by Hermann Abich on JDD’s chapters on the Sandwich Islands [in Geology (1849)].

Sending first volumes on Living and Fossil Cirripedia. Solicits JDD’s opinion, especially on sexual relations of Scalpellum and Ibla, on which he "hardly expect[s] to be believed".

Sends unusual crustacean specimen collected by B. J. Sulivan.

The Sporillus sent by JDD is a very curious species of Acasta [see Living Cirripedia 2: 319].

Asks JDD to identify and give geographical distribution of pieces of coral in which some cirripedes are imbedded.

Gratified by JDD’s opinion of his work.

Discusses problem of homologies of cirripede larva in first stage and reasons for his view.

JDD’s information on corals was just what CD needed.

Would like specimen of blind cave rat described by B. Silliman [Jr] ["On the Mammoth Cave of Kentucky", Am. J. Sci. 2d ser. 11 (1851): 336] for Waterhouse to examine.

Discusses origin of Australian valleys; he disagrees with JDD’s river-erosion hypothesis.

Thanks JDD for information.

Discusses Acasta sporillus.

Comments on review of first volume of Living Cirripedia [Am. J. Sci. 2d ser. 14 (1852): 125–7].

Asks JDD to examine Lerneidae.

Will read with interest the geographical discussion of Crustacea when JDD’s volume [Crustacea (1852–5)] appears. John Lubbock will purchase a copy.

Discusses error in Living Cirripedia.

Admires JDD’s work on Crustacea, corals, and geology.

Commends young John Lubbock to his attention. Hopes JDD can give him encouragement; if he can resist his "great wealth, business, and rank, he may do good work in Natural History".

Thanks JDD for copy of his Crustacea [1852–5]

and D. D. Owen’s Report [of a geological survey of Wisconsin, etc. (1852)].

Responds to JDD’s objections to his views on the three pairs of appendages in larvae of cirripedes. Reports observations which confirm his views.

Gives his confidential opinion of A. White, C. S. Bate, T. Bell, and W. Baird.

Interested in JDD’s observation that Crustacea are not most developed in the tropics. If JDD ever works it out either in number of species or rank, CD would be glad to have result.

Comments on article by Henri Milne-Edwards ["Crustacés", Ann. Sci. Nat. (Zool.) 18 (1852): 109–66].

Asks whether the blind cave animals described by B. Silliman Jr [Am. J. Sci. 2d ser. 11 (1851): 332–9] belong to genera found only on the American continent.

On geographical distribution of Crustacea, CD asks whether northern genera sent species to the Southern Hemisphere or did southern genera send species north?

Does he know of any author who has described fossil trees in South Shetland Islands?

Thanks JDD for replies to queries [in 1925]; would like to know whether teeth of cave rat are of New or Old World type.

Wishes Louis Agassiz would publish his theory of parallels of geological and embryological development. "I wish to believe but have not seen nearly enough as yet to make me a disciple."

Is working hard on variations and origin of species, but fears it will be a couple of years before he publishes.

Describes his recent work on rabbits and pigeons.

The dispersal of land Mollusca is a most difficult problem.

Confesses he is sceptical of immutability of species; discusses difficulty of proving it.

Thanks for sending paper on geological development (Dana 1856). Discusses infertility of species. Discusses first part of Asa Gray’s paper (A. Gray 1856–7). Thanks for note on the Cave Rat. Discusses a new species of fossil cirripede, in the genus Chthamalus. Explains his interest in pigeon breeding.

Asks whether Crustacea from temperate parts of the Southern Hemisphere are more strongly analogous to those in same latitudes of the Northern Hemisphere than are Arctic to Antarctic Crustacea.

Discusses astonishing finds of mammalian and reptilian remains in Purbeck beds; notes reactions of Lyell.

Has doubts about Richard Owen’s recent classification of mammals [J. Proc. Linn. Soc. Lond. (Zool.) 2 (1858): 1–37].

Works away [on Natural selection].

Asa Gray has given valuable assistance.

Thanks him for information concerning Crustacea.

Comments on natural history study in the U. S.

Mentions work done by Huxley on Crustacea ["Description of a new crustacean", J. Geol. Soc. Lond. 13 (1857): 363–9];

John Lubbock on larvae of Diptera.

Has sent JDD a copy of Origin; knows it will horrify him, but hopes JDD will credit him with an honest search for truth. Believes that JDD may come to think there is more to be said "in favour of mutability of species than is at first appreciated".

Grieved at JDD’s illness. Recommends water-cure. Describes his own illness.

The reception of Origin has been more successful than he dreamed.