Letter icon
Letter 3641

Darwin, C. R. to Darwin, W. E.

4 [July 1862]

    Summary Add

  • +

    Reports some observations on the fertilisation of wheat which WED might follow up.

Transcription

Down

4th

My dear William.

I have been looking at the fertilisation of Wheat, & I think, possibly, you might find something curious.— I observed in almost every one of the pollen-grains, which had become empty & adhered to (I suppose the viscid) branching hairs of stigma, that the pollen-tube was always(?) emitted on opposite side of grain to that in contact with the branch of stigma.— This seems very odd.

The branches of stigma are very thin, formed apparently of 3 rows of cells, of hardly greater diameter than pollen-tube:: I am astonished that the tubes shd. be able to penetrate the walls. The specimen examined (not carefully by me) had pollen only during few hours on stigma; & the mere suspicion has crossed me that the pollen-tubes crawl down these branches to the base & there penetrate the stigmatic tissue. The paleæ open for a short period for stigma to be dusted & then close again, & such travelling down of tubes would take place under protection. High powers & good adjustment are necessary— Ears expel anther, when kept in water in room; but the paleæ apparently do not open & expose stigma;— but the stigma could easily be artificially impregnated. If I were you I wd. keep memoranda of points worth attending to. Years ago I asked Hooker how stigma of grasses were impregnated & he seemed to know nothing.—

That d——d. Verbascum will do nothing—

The House is not very cheerful— Lenny is not well, & has glands swollen on neck, which is sometimes serious after Scarlet F.— Horace is not very well today.— Miss Pugh went today, & good old Brodie came. Miss Rendle came yesterday for dancing—

We have got a new grey mare from Mr. Edwards on trial (he is the man for horses) & if she answers we shall sell that beast that fell down.— She is a beautiful canterer. We got all our Hay in splendidly & we have a gigantic stack, worth £140. I have bought £10,000 Lancaster & Carlisle shares.— Here is a dry catalogue of facts. I wish you might be able to come before very long.—

Good night | My dear old fellow | Your affect. Father | C. D.

Mamma says I am to wear a beard.— I am better.

    Footnotes Add

  • +
    f1 3641.f1
    Dated by the reference to CD's investment in the Lancaster and Carlisle Railway Company (see n. 11, below).
  • +
    f2 3641.f2
    William used a microscope in his botanical studies; see also letter to W. E. Darwin, 14 February [1862].
  • +
    f3 3641.f3
    See letter to J. D. Hooker, 13 July [1856] (Correspondence vol. 6). William's botanical sketch-book (DAR 186: 43) contains a note dated 10 July 1862, describing pollen-masses and pollen tubes of `Grasses'.
  • +
    f4 3641.f4
    CD had been impressed by Karl Friedrich von Gärtner's experiments on Verbascum, in which crosses between differently coloured varieties of the same or of different species were found to produce less seed than the parallel crosses between similarly coloured varieties, and he discussed the case in Origin, pp. 270--1. In September 1861, he told Joseph Dalton Hooker that he had decided to test Gärtner's experiments, stating: `I do not think any experiment can be more important on Origin of species; for if he is correct, we certainly have what Huxley calls new physiological species arising' (Correspondence vol. 9, letter to J. D. Hooker, 28 September [1861]; see also Correspondence vol. 10, Appendix VI). CD unsuccessfully sought the requisite specimens from a number of botanical acquaintances (see Correspondence vol. 9, letters to J. D. Hooker, 18 October [1861], 23 October [1861], 1 November [1861], and this volume, letter to C. C. Babington, 20 January [1862]), and on 28 June 1862 began crossing experiments with a specimen of Verbascum transplanted from a nearby field (see the experimental notes dated 28 June and 2 July 1862 in DAR 108: 2). He was, however, unable to obtain fertile seed-pods from these crosses, later concluding that the experimental plant was a sterile hybrid (see letters to J. D. Hooker, 6 October [1862] and 14 [October 1862], and letter to Asa Gray, 16 October [1862]). CD later discussed this experiment in `Specific difference in Primula', pp. 451--4.
  • +
    f5 3641.f5
    Leonard Darwin became ill with scarlet fever on 12 June 1862 (Emma Darwin's diary (DAR 242)).
  • +
    f6 3641.f6
    Horace Darwin.
  • +
    f7 3641.f7
    Miss Pugh had been governess to the Darwin children from January 1857 to January 1859 (see Emma Darwin's diary (DAR 242) and CD's Classed account book (Down House MS)). The Darwins' current governess, Camilla Ludwig, made an extended visit to her family in Hamburg between early June and early November 1862. She was apparently sent away on full pay in order to separate her from Horace Darwin. Stephen Paul Engleheart, the Down surgeon, was concerned that Horace's attachment to her might be exacerbating the illness from which Horace had been suffering since early in the year (see letters from Emma Darwin to W. E. Darwin, [2 March 1862], [27 May 1862], and [6 November 1862] (DAR 219.1: 49, 57, 64), letter to Camilla Ludwig, 26 August [1862], Emma Darwin's diary (DAR 242), and CD's Classed account book (Down House MS)). Miss Pugh was employed as a replacement governess for Elizabeth Darwin from 5 June to 4 July 1862; on 5 July she was paid £5 for `education' (see CD's Classed account book (Down House MS), Emma Darwin's diary (DAR 242), and letter from Emma Darwin to W. E. Darwin, [27 May 1862] (DAR 219.1: 57)).
  • +
    f8 3641.f8
    Brodie had been the nurse at Down House between 1842 and 1851 (Freeman 1978). She apparently remained with the family until the return of Camilla Ludwig in November (see letters from Emma Darwin to W. E. Darwin, [9 August 1862] and [6 November 1862] (DAR 219.1: 61, 64), and Emma Darwin 2: 178).
  • +
    f9 3641.f9
    Miss Rendle has not been identified. There are entries in CD's Account book--cash account (Down House MS), dated 31 March and 6 December 1861, that state: `Miss Rinaldi   Dancing'.
  • +
    f10 3641.f10
    George Edwards was a farmer living in Bromley, Kent (Post Office directory of the six home counties 1862); he is listed in CD's Address book (Down House MS) as a `Horse-Breeder'. In CD's Account book--cash account (Down House MS), CD recorded payments of £42 to `Edwards' on 31 May 1862 and £37 16s. on 14 July 1862.
  • +
    f11 3641.f11
    The reference is to the Lancaster and Carlisle Railway Company; according to CD's Investment book (Down House MS), the stock was purchased on 3 July and 9 July 1862. CD's Account book--banking account (Down House MS) records the settlement of the account on 16 July 1862. See also letter to John St Barbe, [before 3 July 1862].
Maximized view Print letter