To J. D. Hooker 28 November [1871]1
Down, | Beckenham, Kent.
Nov. 28th
My dear Hooker
If you had come here on Sunday, I shd. have asked you whether you could give me seed or seedlings of any Melastomatid which would flower soon to experiment on!! I wrote also to J. Scott to ask if he could give me seed.2 Several years ago I raised a lot of seedlings of a Melastomatous, Greenhouse bush (Monchætus or some such name) from stigmas fertilised separately by the two kinds of pollen, & the seedlings differed remarkably in size & whilst young in appearance; & I never knew what to think of the case (so you must not use it) & have always wished to try again; but they are troublesome beasts to fertilise.3 On other hand I could detect no difference in the product from the 2-coloured anthers of Clarkia.—4 If you want to know further particulars of my experiments on Monochaetus (?) & Clarkia, I will hunt for my notes.— You ask about difference in pollen in the same species.5 All dimorphic & trimorphic plants present such difference in function & in size. Lythrum & (the trimorphic) Oxalis are the most wonderful cases.6 The pollen of the closed imperfect cleistogenic flowers differs in the transparency of the integument, & I think in size. The latter point I cd ascertain from my notes.—7 The pollen or female organs must differ in almost every individual in some manner; otherwise the pollen of vars. & even distinct individuals of same vars would not be so preptent over the individual plants own pollen. Here follows a case of individual difference in function of pollen or ovules or both. Some few individuals of Reseda odorata & of R. lutea, cannot be fertilised, or only very rarely, by pollen of same plant, but can by pollen of any other individual. I chanced to have 2 plants of R. odorata in this state; so I crossed them, & raised 5 seedlings, all of which were self-sterile & all perfectly fertile with pollen of any other individual mignonette.8 So I made a self-sterile race! I do not know whether these are the kinds of facts which you require. Think whether you can help me to seed or better seedlings (not cuttings) of any Melastoma.—
We were all very very sorry that you did not appear on Sunday, & shall be very glad to see with Mr Palgrave (if he is inclined to come) you any day.9 But Next Sunday our house will be full.10 We go to London on Decr. 14th.—for a week. to Erasmus.11 6. Queen Anne St. Thank you much for telling me about the Ayrton affair—12 I am timorous, for I believe politicians are such cowards & so false, & care so little about scientific men, that they will throw any one over board even for such a scamp as Ayrton.
Yours affectionately | C. Darwin
Footnotes
Bibliography
Correspondence: The correspondence of Charles Darwin. Edited by Frederick Burkhardt et al. 29 vols to date. Cambridge: Cambridge University Press. 1985–.
Cross and self fertilisation: The effects of cross and self fertilisation in the vegetable kingdom. By Charles Darwin. London: John Murray. 1876.
Forms of flowers: The different forms of flowers on plants of the same species. By Charles Darwin. London: John Murray. 1877.
‘Three forms of Lythrum salicaria’: On the sexual relations of the three forms of Lythrum salicaria. By Charles Darwin. [Read 16 June 1864.] Journal of the Linnean Society (Botany) 8 (1865): 169–96. [Collected papers 2: 106–31.]
Summary
CD is considering repeating experiments on melastomads in which different pollen sizes produced differing seedling sizes.
Responds to JDH’s query on differences in pollen within the same species.
Letter details
- Letter no.
- DCP-LETT-8087
- From
- Charles Robert Darwin
- To
- Joseph Dalton Hooker
- Sent from
- Down
- Source of text
- DAR 95: 445–8
- Physical description
- ALS 7pp
Please cite as
Darwin Correspondence Project, “Letter no. 8087,” accessed on 8 June 2023, https://www.darwinproject.ac.uk/letter/?docId=letters/DCP-LETT-8087.xml
Also published in The Correspondence of Charles Darwin, vol. 19