Requests tendril-bearing plants.
My dear Hooker
I am getting very much amused by my tendrils— it is just the sort of niggling work which suits me & takes up no time & rather rests me whilst writing. So will you just think whether you know any plant, which you could give or lend me or I could buy with tendrils remarkable in any way, for development, for odd or peculiar structure or even for odd place in natural arrangement.— I have seen or can see Cucurbitaceæ—Passion-flowers—Virginian creeper—Cissus discolor—common Pea & Everlasting pea.— It is really curious the diversification of irritability (I do not mean the spontaneous movement, about which I wrote before & correctly as further observation shows); for instance I find a slight pinch between thumb & finger at end of tendril of Cucurbitaceæ causes prompt movement, but a pinch excites no movement in Cissus.— The cause is that one side alone, (the concave) is irritable in former; wheres both sides are irritable in Cissus, so if you excite at same time both opposite sides there is no movement; but by touching with a pencil the two branches of tendril in any part whatever you cause movement towards that point; so that I can mould by mere touch the two branches into any shape I like
&c &c The peduncle of tendril is either not sensitive or sensitive only to prolonged though slight pressure &c &c.—
If you can screw out a little time do come here for a Sunday, I shd. so like it, & I have been better of late & shd. stand some talking well.—
What a splendid number the last of N. Hist. Review.— Capital, as they seemed to me, Botanical & Zoological papers.— The embryology of Echinodermata seemed capitally done. I suppose I owe to Oliver the capital & clear article on Linum.
GoodBye, it is awfully hot.— Ever yours affect— | C. Darwin
- f1 4241.f1CD refers to his experiments on climbing plants, begun in June 1862. See letters to J. D. Hooker, 25 [June 1863] and 1 July .
- f2 4241.f2On the back of CD's letter Hooker listed the following genera and family: `Cobæa | Bignonia | Mutisia | Gloriosa | Flagellaria | Lygodium. | Smilax | Leguminosæ'. See also letter from J. D. Hooker, [21 July 1863].
- f3 4241.f3CD's notes on his observations and experiments on climbing plants are in DAR 157.1 and DAR 157.2. These include notes on several members of the Cucurbitaceae, namely: Echinocystis lobata, dated 16 June -- 24 May 1864 (DAR 157.2: 29--51 and 53); Hanburya mexicana, dated 12 October  (DAR 157.2: 52); Anguria warscewiczii, dated 29 April 1864, and Zanonia indica, dated 11 April and 20 May  (DAR 157.2: 54). There are also notes on several species of Passiflora (passion flower), dated 27 [July 1863] -- 4 August  (DAR 157.2: 69--77); Ampelopsis hederacea (Virginia creeper), dated 1 July -- 16 August  (DAR 157.2: 65--7); Cissus discolor, dated 30 June -- 18 July  (DAR 157.2: 55--6); Pisum sativum (common pea), dated 30 July -- 23 August  (DAR 157.2: 15--20); and Lathyrus grandiflorus (everlasting pea), dated 10--15 November  (DAR 157.2: 22). These species are discussed in `Climbing plants', pp. 65--7, 73--9, 83--7, and 89--91.
- f4 4241.f4See letter to J. D. Hooker, 25 [June 1863].
- f5 4241.f5CD's notes from these experiments, dated 30 June -- 18 July  are in DAR 157.2: 55--6. In his discussion of Cissus discolor in `Climbing plants', CD stated (pp. 83--4):
At the beginning of my work, and before examining this plant, I had observed only those tendrils which are sensitive on one side, and these when lightly pressed between the finger and thumb become curved; but on thus pinching many times the tendrils of this Cissus no curvature ensued, and I was at first falsely led to infer that they were not at all sensitive to a touch.
- f6 4241.f6CD refers to the July 1863 issue of the Natural History Review, of which Hooker was one of the editors; CD's unbound copy of this issue of the journal is in the Darwin Library--CUL.
- f7 4241.f7Thomson 1863--4.
- f8 4241.f8[Oliver] 1863d. Daniel Oliver, who was one of the botanical editors of the Natural History Review, had indicated that he wished to review `Two forms in species of Linum' for the journal (see letter from Daniel Oliver, 27 February 1863; see also letter from J. D. Hooker, [24 March 1863] and n. 11).