To W. T. Thiselton-Dyer 14 July [1878]1
Down, | Beckenham, Kent. | Railway Station | Orpington. S.E.R.
July 14th
My dear Dyer
Thalia dealbata was sent me from Kew— it has flowered & after looking casually at the flowers, they have driven me almost mad & I have worked at them for a week:— it is as grand a case as that of Catasetum.2
Pistil vigorously motile, (so that whole flower shakes when pistil suddenly coils up.) when excited by a touch the two filaments produced laterally & transversely across the flower (just over the nectar) from one of the petals or modified stamens. It is splendid to watch the phenomenon under a weak power when a bristle is inserted into a young flower which no insect has visited. As far as I know Stylidium is sole case of sensitive pistil & here it is the pistil & stamens.3 In Thalia cross-fertilisation is ensured by the wonderful movement, if bees visit several flowers.
I have now relieved my mind & will tell the purpose of this note—viz if any other species of Thalia besides T. dealbata shd. flower with you, for the love of Heaven & all the Saints, send me a few in tin-box with damp moss,4
Your insane friend | Ch. Darwin
Footnotes
Bibliography
Orchids 2d ed.: The various contrivances by which orchids are fertilised by insects. By Charles Darwin. 2d edition, revised. London: John Murray. 1877.
Summary
Movement and sensitivity of flower parts; relationship to cross-fertilisation.
Letter details
- Letter no.
- DCP-LETT-11605
- From
- Charles Robert Darwin
- To
- William Turner Thiselton-Dyer
- Sent from
- Down
- Source of text
- Royal Botanic Gardens, Kew (Thiselton-Dyer, W. T., Letters from Charles Darwin 1873–81: 135–6)
- Physical description
- ALS 4pp
Please cite as
Darwin Correspondence Project, “Letter no. 11605,” accessed on 8 October 2024, https://www.darwinproject.ac.uk/letter/?docId=letters/DCP-LETT-11605.xml