To Thomas Rivers   [14 February 1863]1

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

Saturday

My dear Sir

Absence from home, for a little rest, for the last nine days has prevented me from thanking you sooner for your last letter.2

You could not by any possibility have given me a more curious case of inheritance than that of the Ash, which produced weeping seedlings & itself lost the weeping peculiarity!3 It is capital for my purpose. I am also very glad to hear of the Thorn.—4 I am nearly sure I have already in my M.S. index from “Loudon’s Gard Mag.” your first case of 20,000, or 30,000 seedlings from the common weeping ash.—5 I wish I could get authentic information on the weeping Elm.—6

What you say of seedlings conquering each other well illustrates the “struggle for existence” & “natural selection”.7 I have often & often looked at a crowd of natural seedlings with just such feelings & reflexions as yours.—

With hearty thanks for your capital facts | My dear Sir | Yours sincerely | Ch. Darwin

The date is established by CD’s reference to his stay in London (see n. 2, below); in 1863, 14 February was a Saturday.
Letter from Thomas Rivers, [3 February 1863]. CD was in London from 4 to 14 February 1863 (see ‘Journal’ (Correspondence vol. 11, Appendix II)).
The letter from Rivers of [3 February 1863] is incomplete; however, CD quoted the information on the weeping ash contained in the missing portion of the letter in Variation 2: 19. CD cited the weeping habit of trees as an example of ‘how feeble, capricious, or deficient the power of inheritance sometimes is’, the weeping habit being transmitted to the seedlings sometimes strongly and sometimes weakly (see ibid., pp. 17–19).
In the missing portion of his letter of [3 February 1863], Rivers evidently provided information on the young trees resulting from a cross between a species of weeping thorn (Crataegus oxyacantha) and a ‘not-weeping variety’ (see Variation 2: 18).
In 1834, Rivers reported that he had sown over 20,000 seedlings of the weeping ash (Fraxinus excelsior), none of which inherited the weeping characteristic. The letter reporting this information was published in the Gardener’s Magazine 10 (1838): 408, and was cited in Variation 2: 19. CD’s copy of the volume has a manuscript index pencilled at the back and is preserved in the Darwin Library–CUL. John Claudius Loudon founded the Gardener’s Magazine in 1826 and edited it until his death in 1843 (DNB).
Rivers later raised a number of seedlings from different varieties of weeping elm at CD’s request, none of which inherited the weeping habit (see Variation 2: 19).

Manuscript Alterations and Comments

3.2 & "natural selection".] interl

Please cite as “DCP-LETT-3982,” in Ɛpsilon: The Charles Darwin Collection accessed on 5 June 2025, https://epsilon.ac.uk/view/dcp-data/letters/DCP-LETT-3982