To J. D. Hooker   29 January [1867]1

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

Jan 29th

My dear Hooker

Very many thanks for 2 Plumbago; but I am very sorry that I have caused you trouble in vain, as seed alone wd be of service to me for Dimorphism.—2

I have read your concluding paper & it is excellent.3 Such papers will do far more than regular Treatises on the subject to convert people to the derivation Theory.—4 You pay me about Distribution an enormous compliment & really I think much too strong. It rejoices my inward heart to find we accord so very closely.5 I think you lay too much weight on the affinity not going strictly with geographical distance.— The Azores, (though I know some fragments of miocene beds have been found there) struck me when there in general aspect as a far more modern group, (with still active volcano, fumarole &c &c) than Madeira; & wd not this account to great extent for more strictly European flora:6 I suppose you will admit that each isld has received many of its plants, not from other isld, but from continent; I remember coming from your paper on Galapagos to this conclusion.7 At top of third column, you hardly put case about volcanic islands quite fairly; for I do not suppose anyone would object as improbable to very many large groups of oceanic islds. being volcanic; but the difficulty arises from all oceanic islands being volcanic; & volcanos, whilst active, it may be added, characterise rising, not subsiding areas.—8 It is a splendid paper.

Yours affect | C. Darwin

1
The year is established by the references to the publication of J. D. Hooker 1866a (see n. 3, below).
2
CD had asked for Plumbago seeds in December 1866 (Correspondence vol. 14, letter to J. D. Hooker, 24 December [1866]), and Hooker had evidently sent specimens after 12 January 1867 (see letter to J. D. Hooker, 9 January [1867], and letter from J. D. Hooker, [12 January 1867]).
3
CD refers to the fourth instalment in Gardeners Chronicle, 26 January 1867, pp. 75–6, of Hooker’s article on insular floras (J. D. Hooker 1866a). See the letters to J. D. Hooker, 9 January [1867] and n. 1, 15 January [1867], and 21 January [1867], for CD’s comments on the first three instalments.
4
Hooker discussed how the ‘hypothesis of trans-oceanic migration’ and the ‘theory of the derivative origin of species’ could contribute to the understanding of the distribution of plants on small oceanic islands. He added: ‘if many of the phenomena of oceanic island Floras are thus well explained by the theory of the derivative origin of species, and not at all by any other theory, it surely is a strong corroboration of that theory’ (J. D. Hooker 1866a, p. 75). At the close of the paper, Hooker made a humorous analogy concerning the reception of the ‘Derivative doctrine of species’ at the 1860 meeting of the British Association at Oxford, and at the 1866 meeting (ibid., pp. 75–6; see also Correspondence vol. 14).
5
In the third and fourth instalments of J. D. Hooker 1866a, pp. 50, 51, and 75, Hooker discussed at length CD’s hypothesis of trans-oceanic migration as a means of plant and animal distribution, and presented it as one of two explanatory hypotheses for plant distribution on oceanic islands (see also letter to J. D. Hooker, 21 January [1867] and n. 3). Hooker discussed the ‘many powerful arguments’ that CD had presented in support of his hypothesis (ibid., p. 51), later adding (ibid., p. 75): It shows a power and skill of bringing facts to bear, and a fertility of invention in devising means of verifying these facts, that almost compel me to agree with him in regarding oceanic transport to be, in the present state of science, the principal and most probable means by which oceanic islands have been stocked with plants. Towards the end of the paper, Hooker wrote (ibid.): The great objection to the continental extension hypothesis is, that it may be said to account for everything, but to explain nothing; it proves too much: whilst the hypothesis of trans-oceanic migration, though it leaves a multitude of facts unexplained, offers a rational solution of many of the most puzzling phenomena that oceanic islands present.
6
Hooker noted that there were more European plants on the Azores, even though the islands lay more than twice as far from the continent than did Madeira (J. D. Hooker 1866a, p. 75); he included what he called an imperfect explanation that Madeira, receiving more immigrants, exhibited ‘the sharper struggle’. For CD’s impressions of volcanic activity on the Azores, which he visited on the Beagle in September 1836, see R. D. Keynes ed. 1988, pp. 437–41, and Correspondence vol. 2, letter to William C. Redfield, 24 February [1840]. CD had discussed European plants on the Azores and Madeira in Origin, pp. 314, 363, 390–1. CD and Hooker also discussed plant distribution on the Azores and Madeira in 1866 (Correspondence vol. 14). The Miocene origins and some of the volcanic history of the Atlantic Islands were discussed in C. Lyell 1867–8, 2: 403–11.
7
CD refers to Hooker’s paper ‘On the vegetation of the Galapagos Archipelago’ (J. D. Hooker 1846), based on CD’s collection of plant specimens; see also J. D. Hooker 1845. CD believed that many of the animal species, including birds, on the Galápagos Islands had derived from those in South America, but that few had dispersed from one island of the archipelago to another (see Journal of researches 2d ed., p. 398, and Origin, pp. 398–403; see also Correspondence vol. 3).
8
In his article, Hooker discussed the improbability of subsiding oceanic islands containing fossil mammals (J. D. Hooker 1866a, p. 75).

Manuscript Alterations and Comments

2.1 far] interl
2.4 much] interl
2.5 geographical] interl
2.7 when there] interl
2.8 fumarole] above del ‘hot-springs &c’
2.10 each] interl after del ‘the’
2.10 has] interl
2.14 oceanic islands] interl

Please cite as “DCP-LETT-5381,” in Ɛpsilon: The Charles Darwin Collection accessed on 5 June 2025, https://epsilon.ac.uk/view/dcp-data/letters/DCP-LETT-5381