Ɛpsilon

To J. D. Hooker   22 October 1881

66 Hills Road | Cambridge

Oct 22d. 1881.

(Home on 27th.)

My dear Hooker

We are staying for a week with Horace here in Cambridge, as I much wanted a change & rest.1 Now I am going to bother you or Dyer, if the latter has returned. I sadly want the plants in enclosed list.2 I tried to get a Papaw but failed from Veitch, where I got Nepenthes Dionæa & some other plants.3 I am investigating the action of Carbonate of Ammonia, on chlorophyll, which makes me want the plants in my list.4 I have incidentally, observed one point in Euphorbia, which has astonished me, viz that in the fine fibrous roots of Euphorbia, the alternate rows of cells in these roots must differ physiologically, though not in external appearance, as their contents after the action of Carbonate of Ammonia differ most conspicuously.5

(Now for another subject: Dr. King writes that he has dispatched a very fine specimen of Dischidia Rafflesiana in spirits to me, & he sends a drawing & extract from Wallich.— What an extraordinary case it seems to be: from what Dr. King says & the drawings it looks as if the plant manufactured little pitchers of manure-water, so that its roots might be nourished by the contents.—6 Now I have not, of course, histological knowledge enough to undertake the examination of the minute structure of these pitchers, & do you know of any one with knowledge enough who wd like to undertake the work: always supposing that the work has not already been done. If no one else wd do so, perhaps Frank would; but he likes physiological work, more than morphological work.—7

Please observe that we return home on Thursday 27th, so that if you can send me any plants, they ought not to be despatched before that day.— Ever my dear Hooker | Yours very sincerely | Ch. Darwin

P.S. | Wiesner of Vienna has just published a book, vivisecting me in the most courteous, but awful manner, about the “Power of Movement in Plants”.—8 Thank Heaven he admits almost all my facts, after retrying all my experiments; but gives widely different interpretations of the facts.— I think he proves me wrong in several cases, but I am convinced that he is utterly erroneous & fanciful in other explanations. No man was ever vivisected in so sweet a manner before, as I am in this book.—

Pray give my kind farewell to Asa Gray & I thank him for the card received just as we were leaving home.—9

[Enclosure]

(Young Papaw tree, (but with roots)

(Sarracenia— a single leaf or pitcher wd. do, if not old & sent damp in tin-box.— Or I could return plant.—)

(Drosophyllum— a very small plant wd suffice & I could return it.)

(Any one or 2 or 3 Euphorbiaceous plants, except Euphorbia & Phyllanthus both of which I possess.— I fear that Pointsettia hardly differs from Euphorbia, otherwise this wd. do for one: I bought seeds of Pointsettia, but not one germinated.10

1
The Darwins visited Cambridge from 20 to 27 October 1881, staying with their son Horace Darwin and his wife, Ida (CD’s ‘Journal’ (Appendix II)).
2
William Turner Thiselton-Dyer and his wife, Harriet Anne, had gone on a six-week holiday to the continent on 7 September 1881 (see letter from J. D. Hooker, 7 September 1881, and letter from J. D. Hooker, [23 October 1881]).
3
The papaw or papaya, as it is more commonly known now, is Carica papaya. Veitch & Sons was a nursery firm often used by CD; they carried many exotic plants at their Chelsea branch (Shephard 2003). Nepenthes is a genus of tropical pitcher-plants sometimes referred to as monkey cup; Dionaea is Venus fly trap, a native of eastern North America.
4
CD’s notes on the action of carbonate of ammonia (ammonium carbonate; (NH4)2CO3) on chlorophyll, dated between 31 August and November 1881, are in DAR 52: F22–98. The results of these experiments were published in the Journal of the Linnean Society of London (‘Action of carbonate of ammonia on chlorophyll’).
5
CD’s notes on the absorption of carbonate of ammonia by roots of Euphorbia peplus (petty spurge) and E. myrsinites (myrtle spurge), dated from 28 July to 14 November 1881, are in DAR 62: 2–5, 36–41. Notes on E. ornithopus (bird’s foot euphorbia) and E. rhipsaloides (a synonym of E. tirucalli, Indiantree spurge), dated from 24 to 29 December 1881, are in DAR 62: 42–3. The results of these experiments were published in ‘Action of carbonate of ammonia on roots’.
6
See letter from George King, 13 September 1881 and n. 1. Nathaniel Wallich had illustrated and described Dischidia rafflesiana (a synonym of D. major) in Plantae Asiaticae rariores (Wallich 1830–2, 2: 35–6 and plate 142).
7
Francis Darwin added a note on Dischidia rafflesiana to Insectivorous plants 2d ed., pp. 366–7 n. Francis discussed various theories about the function of the ‘pitchers’, but concluded that their use could not be considered definitely settled. One of the most comprehensive studies of the pitchers of Dischidia rafflesiana was Melchior Treub’s ‘Sur les urnes du Dischidia Rafflesiana Wall’ (Treub 1883), in which all of the previous literature on the nature and function of the pitchers was reviewed. Francis Darwin referred to this work in his note for Insectivorous plants 2d ed.
8
Julius Wiesner had sent CD a copy of his book Das Bewegungsvermögen der Pflanzen. Eine kritische Studie über das gleichnamige Werk von Charles Darwin, nebst neuen Untersuchungen (The power of movement in plants. A critical study of the work of the same name by Charles Darwin, together with new investigations; Wiesner 1881). For a discussion of some of Wiesner’s criticisms, see the letter to Francis Darwin, 22 [October 1881].
9
Asa Gray left Kew on 22 October 1881 (see letter from J. D. Hooker, [23 October 1881]). The card has not been found.
10
Sarracenia is the genus of trumpet pitchers native to North America. Drosophyllum is the monotypic genus of Portuguese sundew or dewy pine. Euphorbia is the genus of spurges; Phyllanthus is the genus of leaf flower. Both genera were in the family Euphorbiaceae, but more recently Phyllanthus has been placed in the family Phyllanthaceae. Poinsettia is now an unaccepted genus whose former species are all placed in Euphorbia.

Manuscript Alterations and Comments

0.1 Cambridge] before del ‘Down, | Beckenham, Kent. | Railway Station | Orpington. S.E.R.’
1.3 a Papaw] ‘a’ after del caret
1.3 but failed] interl
1.4 Dionæa] interl
1.5 on chlorophyll] after del ‘which’
1.5 the] ‘e’ over ‘ese’
1.7 alternate] after del ‘generally’
1.7 in] after del ‘, forming’
1.9 most] interl
2.1 (Now] square bracket in ms
2.4 & the drawings] interl
2.8 always … done 2.9] interl
4.3 almost] interl
4.3 retrying] after del ‘going over’
Enclosure:
1.1 (Young] square bracket in ms
2.1 (Sarracenia … ) 2.2] square brackets in ms
3.1 (Drosophyllum … )] square brackets in ms
4.1 (Any] square bracket in ms
4.2 I possess] after del ‘wd d’

Please cite as “DCP-LETT-13420,” in Ɛpsilon: The Charles Darwin Collection accessed on 5 June 2025, https://epsilon.ac.uk/view/dcp-data/letters/DCP-LETT-13420