To ? 30 October [1869 or 1870]1
Down. | Beckenham | Kent. S. E.
Oct. 30th.
My dear Sir
The case of the Habenaria is very interesting as shewing how distant plants may be crossed; & I wish I had known of it before drawing up the notes of which I send a copy by this post.2
The Lychnis-case well deserves investigation; but I doubt whether the bi-sexual condition can be the result of crossing (tho’ this wd please me much;) for Gärtner crossed the two sp. repeatedly, & cd hardly have failed to have observed in the hybrids a tendency to hermaphroditism.3
If the smaller grains of pollen are of equal size & really sound, I shd suspect a reversion to a dimorphic condition, like that of Primula. I have long had reason to suspect that some dioicous plants originate from the suppression of the reversed sexes in the 2 forms of dimorphic plants.4 The enclosed diagram, which is little better than a hieroglyphic, will perhaps explain what I mean.5
Your hermaphrodite plants ought all to be transplanted into a garden, carefully observed, the small-grained pollen experimented on, with insects, of course, carefully excluded.
This is what I shd do if I had the plants, & I think that you wd find it worth while to observe them with care—
Pray believe me | My dear Sir | yours very faithfully | Ch. 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.
Dressler, Robert L. 1981. The orchids: natural history and classification. Cambridge, Mass., and London: Harvard University Press.
Gärtner, Karl Friedrich von. 1849. Versuche und Beobachtungen über die Bastarderzeugung im Pflanzenreich. Mit Hinweisung auf die ähnlichen Erscheinungen im Thierreiche, ganz umgearbeitete und sehr vermehrte Ausgabe der von der Königlich holländischen Akademie der Wissenschaften. Stuttgart: E. Schweizerbart.
Natural selection: Charles Darwin’s Natural selection: being the second part of his big species book written from 1856 to 1858. Edited by R. C. Stauffer. Cambridge: Cambridge University Press. 1975.
Orchids: On the various contrivances by which British and foreign orchids are fertilised by insects, and on the good effects of intercrossing. By Charles Darwin. London: John Murray. 1862.
Summary
Comments on a case of crossing distant plants of Habenaria
and on hermaphroditism in hybrid plants.
Letter details
- Letter no.
- DCP-LETT-6961A
- From
- Charles Robert Darwin
- To
- Unidentified
- Source of text
- King Edward VI High School, Stafford
- Physical description
- LS(A) 3pp †
Please cite as
Darwin Correspondence Project, “Letter no. 6961A,” accessed on 18 April 2024, https://www.darwinproject.ac.uk/letter/?docId=letters/DCP-LETT-6961A.xml
Also published in The Correspondence of Charles Darwin, vol. 17