To B. D. Walsh   4 December [1864]1

Down. | Bromley. | Kent. S.E.

Dec. 4th.—

My dear Sir

I have been greatly interested by your account of your American life.2 What an extraordinary & self-contained life you have led! & what vigour of mind you must possess to follow science with so much ardour after all that you have undergone.— I am very much obliged for your pamphlet on Geograph. Distrib,—on Agassiz &c.— 3 I am delighted at the manner in which you have bearded this lion in his den. I agree most entirely with all that you have written. What I meant, when I wrote to Agassiz to thank him for a bundle of his publications, was exactly what you suppose.4 I confess, however, I did not fully perceive how he had mistated my views; but I only skimmed through his “Method of Study” & thought it a very poor Book.— I am so much accustomed to be utterly misrepresented that it hardly excites my attention. But you really have hit the nail on the head capitally.5 All the younger good naturalists, whom I know think of Agassiz as you do; but he did grand service about Glaciers & Fish.—6 About the succession of forms, Pictet has given up his whole views,7 & no geologist now agrees with Agassiz.— I am glad that you have attacked Dana’s wild notions:8 I have a great respect for Dana, but I declare I fear that his long illness has somewhat enfeebled his brain.—9 If you have opportunity read in Transact. Linn. Soc.y. Bates on mimetic Lepidoptera of Amazons;10 I was delighted with his paper.—

I have got a notice of your views about the female Cynips inserted in N. Hist. Review; whether the notice will be favourable I do know not; but anyhow it will call attention to your views.—11 Many thanks about the connexion of male & female insects & their organs.—12 It occurred to me as just possible that the organs for oviposition might be very different in allied species; & that this might lead by correlation to differences in the male parts; but this was a simple groundless conjecture on my part, & not applicable anyhow to Bombus. Would species of Bombus copulate differently?13

I enclose a Photograph made of me by one of my sons, & I have no other.—14 I wrote to Westwood for a Carte for you, but I have received no answer.15 I have been told that he is most bitter about species, & perhaps wishes to show his feelings by this want of common courtesy to us both.—16

As you allude in your paper to the believers in change of species, you will be glad to hear that very many of the very best men are coming round in Germany.— I have lately heard of Häckel, Gegenbaur, F. Müller, Leuckart, Claparede, Alex. Braun, Schleiden &c &c.—17 So it is, I hear, with the younger Frenchmen.—18

Pray believe me | My dear Sir | Yours very sincerely | Ch. Darwin

1
The year is established by the relationship between this letter and the letter from B. D. Walsh, 7 November 1864.
3
CD refers to Walsh’s paper, ‘On certain entomological speculations of the New England school of naturalists’ (Walsh 1864b). An annotated copy is in the Darwin Pamphlet Collection–CUL. Walsh criticised Louis Agassiz’s views on the distinctness of Old and New World insects, and the underlying theory of special creation (Walsh 1864b, p. 220).
4
See letter to Louis Agassiz, 12 April 1864, and letter from B. D. Walsh, 7 November 1864. In the letter to Louis Agassiz, 12 April 1864, CD thanked Agassiz for a presentation copy of Methods of study in natural history (Agassiz 1863b), and for other publications. A lightly annotated copy of Agassiz 1863b is in the Darwin Library–Down (see Marginalia 1: 13). There are a number of Agassiz’s publications in the Darwin Pamphlet Collection–CUL, the Darwin Library–CUL, and the Darwin Library–Down (see Marginalia 1: 8–14). See also Correspondence vol. 11, letter from Asa Gray, 23 November 1863, and this volume, letter to A. R. Wallace, 1 January 1864.
6
Agassiz formulated a theory of the ice age in Etudes sur les glaciers (Agassiz 1840b); for an assessment of the impact of his theory, see Davies 1969 and DSB. His major work on fish was Recherches sur les poissons fossiles (Agassiz 1833–43). He was awarded the Copley Medal in 1861 for his work in palaeontology and other branches of science (see Proceedings of the Royal Society of London 11 (1860–2): 461–3). See also Winsor 1991.
7
In his letter of 7 November 1864, Walsh suggested that the Swiss palaeontologist François Jules Pictet de la Rive shared Agassiz’s view that the animals of each geological epoch were specifically distinct. CD described Pictet de la Rive as a believer in the immutability of species (Origin, p. 302; Origin 3d ed., p. 336; Peckham ed. 1959, pp. 506, 519), who had been ‘shaken … in his firm belief’ by evidence that fossils from two successive formations were far more closely related to each other than were fossils from two remote formations (Origin, p. 335; Peckham ed. 1959, p. 546). See also Correspondence vol. 8, letter to A. R. Wallace, 18 May 1860. In Traité élémentaire de paléontologie (1844–6), Pictet de la Rive advanced a theory of successive creations to explain the origin of distinct types; in the second edition (1853–7), he admitted the possibility of species modification within certain limits (see Tort 1996, pp. 3439–40). Annotated copies of Pictet de la Rive 1844–6 (vols. 1 and 3 only) and Pictet de la Rive 1853–7 are in the Darwin Library–CUL (see Marginalia 1: 668–75). There is an annotated copy of Pictet de la Rive 1864, with a long note by CD attached, in the Darwin Pamphlet Collection–CUL. For Pictet de la Rive’s views on Origin, see Correspondence vol. 8, letter from F. J. Pictet de la Rive, 19 February 1860, and Pictet de la Rive 1860.
8
Walsh was highly critical of James Dwight Dana’s recent work on entomological classification (see Walsh 1864b, p. 238, and Dana 1864a). In his major work on crustaceans, Dana claimed that cephalisation, which he defined as the subordination of body structures to cerebral functions, was a fundamental principle of classification (Dana 1853, pp. 1396–8). He later applied this principle to other divisions of the animal kingdom (Dana 1863a–c) and, most recently, to insects (Dana 1864a). For CD’s views on the principle of cephalisation, see Correspondence vol. 11, letter to Charles Lyell, 17 [February 1863]. An annotated copy of Dana 1853 is in the Darwin Library–CUL (see Marginalia 1: 178–9); annotated copies of Dana 1863a, 1863c, and 1864a are in the Darwin Pamphlet Collection–CUL. See also letter to Asa Gray, 25 February [1864] and n. 11.
9
In 1859, Dana suffered a nervous breakdown, from which he never fully recovered (DAB). See Correspondence vol. 11, letter to Charles Lyell, 14 August [1863] and n. 5.
10
CD refers to the paper by Henry Walter Bates, ‘Contributions to an insect fauna of the Amazon Valley. Lepidoptera: Heliconidæ’ (Bates 1861). CD wrote an unsigned review of Bates’s paper in the April 1863 issue of the Natural History Review (‘Review of Bates on mimetic butterflies’).
11
A notice of Walsh’s paper ‘Dimorphism in the hymenopterous genus Cynips’ (Walsh 1864a), written by John Lubbock, appeared in the January 1865 issue of Natural History Review (Lubbock 1865a). See letter to B. D. Walsh, 21 October [1864], and letter from John Lubbock, 3 November 1864. An annotated copy of Walsh 1864a is in the Darwin Pamphlet Collection–CUL.
12
See letter from B. D. Walsh, 7 November 1864. CD had requested information on the reproductive organs of various insects in his letter to Walsh of 21 October [1864].
13
In his letter of 1 March 1865 (Correspondence vol. 13), Walsh discussed the variety of external reproductive structures of Bombus, denying, however, that any species of Bombus or any other genus could copulate differently from members of the same genus.
14
CD refers to a photograph taken by William Erasmus Darwin in 1864 (see letter from W. E. Darwin, [19 May 1864] and n. 8, and frontispiece to this volume).
15
The letter to John Obadiah Westwood has not been found. CD had not yet received the letter from J. O. Westwood, 2 December 1864, when this letter was written.
16
On Westwood’s response to CD’s theory expressed in Origin, see Correspondence vol. 8, letter to W. B. Tegetmeier, 30 July [1860] and n. 4, and Appendix VII and n. 1.
17
In his letter of 26 October 1864, Ernst Haeckel discussed the favourable reception of CD’s views on the origin of species by Carl Gegenbaur, Fritz Müller, Max Johann Sigismund Schultze, Rudolf Leuckart, Edouard Claparède, Alexander Carl Heinrich Braun, and August Schleicher. ‘Schleiden’ may be a mistake for Schleicher or a reference to the German botanist Matthias Jacob Schleiden. See also letter from Ernst Haeckel, 9 [July 1864] and n. 6.
18
See letter from Hugh Falconer, 3 November 186[4]. On the reception of CD’s work in France, see Corsi and Weindling 1985, Tort 1996, and J. Harvey 1997a.

Manuscript Alterations and Comments

1.11 nail on] ‘on’ over ‘t’
1.17 in Transact. Linn. Soc.y] interl
2.1 a notice] ‘a’ interl
2.2 do] interl
2.5 species;] after del illeg

Please cite as “DCP-LETT-4695,” in Ɛpsilon: The Charles Darwin Collection accessed on 5 June 2025, https://epsilon.ac.uk/view/dcp-data/letters/DCP-LETT-4695