To Daniel Oliver 5 October [1860]1
15 Marine Parade | Eastbourne
Oct. 5th
My dear Sir
I thank you for two notes.2 It was a capital thought your sending me the gum itself (so ingeniously bottled or quilled); I tried it on 3 leaves, & it produced no effect; & I tried thicker gum on 5 other leaves with no effect, & I subsequently proved that these leaves were good ones.3 If a leaf is feeble & does not secrete copiously, the gum dries & draws together all the hairs which it has touched; & this, I imagine, must have been cause of the apparent inflection in your case. At last I have come to a puzzler, for I find Carb. of Soda causes inflection;4 but I have sent to London for pure C. of soda, & as that sold by Druggists is not pure. But I strongly suspect I have come across a poser. I am, however, trying my experiments in another fashion, which may throw light on subject.— I find the glands at end of Hairs are absorbers as well as secreters. The change which takes place in the Hairs after inflection is very curious. The currents & movements in the cells strike me in my ignorance as marvellous.—
You are very kind in your second note to say that I must not apologise for all the trouble which I have caused; but pray thank Mr Croker for enquiring about the Dionæa.—5 Also please give my best thanks to Sir William for his wish to oblige me;6 I shall be intensely curious to examine the leaves; if I cannot get a plant. If the Dionæa commonly catches only small fry, I shd. not be surprised at a fat fly being too much for its digestion; at least I have found bits of raw meat often, indeed I think generally, kill the leaf of the Drosera. I shd like to hear whether Croker is pretty certain of this fact.—
I am very glad to hear that you are experimentising on the leaves in water. I have long thought that naturalists make far too few experiments.—
My dear Sir | Yours very sincerely | C. Darwin
Do you possess a copy of my “Origin of Species”; if you do not, I should much like to have the pleasure of sending you one.—7
Footnotes
Bibliography
Journal of researches: Journal of researches into the geology and natural history of the various countries visited by HMS Beagle, under the command of Captain FitzRoy, RN, from 1832 to 1836. By Charles Darwin. London: Henry Colburn. 1839.
Origin: On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. By Charles Darwin. London: John Murray. 1859.
Summary
A poser: carbonate of soda produces inflection rather than contraction in Drosera. Possible solution: glands at end of hairs absorb as well as secrete. Fascinated by currents in cells after inflection.
Letter details
- Letter no.
- DCP-LETT-2939
- From
- Charles Robert Darwin
- To
- Daniel Oliver
- Sent from
- Eastbourne
- Source of text
- DAR 261.10: 14 (EH 88205998)
- Physical description
- ALS 5pp
Please cite as
Darwin Correspondence Project, “Letter no. 2939,” accessed on 20 April 2024, https://www.darwinproject.ac.uk/letter/?docId=letters/DCP-LETT-2939.xml
Also published in The Correspondence of Charles Darwin, vol. 8