To J. D. Hooker 28 March [1878]1
Down, | Beckenham, Kent. | Railway Station | Orpington. S.E.R.
March. 28th
My dear Hooker
I am extremely obliged for the plants, & I do hope not to give any more trouble to Kew for a long time.— Pray thank Dyer cordially about the geotropic plants: we have now excellent materials if we can make out anything about geotropism.2 Most, indeed nearly all, of the plants shall be returned in due time. But the geotropic ones must be kept until they make fresh growths.
It is very curious how differently plants withstand frost. Most of the Cassias are extraordinarily sensitive, whereas a seedling of C. pubescens will withstand quite a sharp frost; & so in many other cases.3 This gives us infinite trouble for we cannot judge except by graduated trials, how long to expose any plant so as to injure without killing it
Ever yours | Ch. Darwin
Footnotes
Bibliography
Movement in plants: The power of movement in plants. By Charles Darwin. Assisted by Francis Darwin. London: John Murray. 1880.
Summary
Studying geotropism.
Experiments using exposure to frost to study nyctitropism are difficult to perform because species vary in frost tolerance.
Letter details
- Letter no.
- DCP-LETT-11452
- From
- Charles Robert Darwin
- To
- Joseph Dalton Hooker
- Sent from
- Down
- Source of text
- DAR 95: 471–2
- Physical description
- ALS 3pp
Please cite as
Darwin Correspondence Project, “Letter no. 11452,” accessed on 20 April 2024, https://www.darwinproject.ac.uk/letter/?docId=letters/DCP-LETT-11452.xml