skip to content

Darwin Correspondence Project

To Fritz Müller   23 February 1881

Down, | Beckenham, Kent. | (Railway Station | Orpington. S.E.R.)

Feb. 23d 1881

My dear Sir

Your letter has interested me greatly, as have so many during many past years. I thought that you wd. not object to my publishing in Nature some of the more striking facts about the movements of Plants, with a few remarks added to show the bearing of the facts. The case of the Phyllanthus which sometimes turns up its leaves on the wrong side is most extraordinary & ought to be further investigated.1

Do the leaflets sleep on the following night in the usual manner? Do the same leaflets on successive nights move in the same strange manner? I was particularly glad to hear of the strongly marked cases of paraheliotropism.—2 I shall look out with much interest for the publication about the Figs. The creatures which you sketch are marvellous & I shd not have guessed that they were Hymenoptera.3 Thirty or forty years ago I read all that I cd. find about caprification & was utterly puzzled.4 I suggested to Dr. Crüger in Trinidad to investigate the wild figs, in relation to their cross-fertilisation, & just before he died he wrote that he had arrived at some very curious results, but he never published, as I believe on the subject.—5

I am extremely glad that the inundation did not so greatly injure your scientific property; though it would have been a real pleasure to me to have been allowed to have replaced your scientific apparatus.6 I do not believe that there is anyone in the world who admires your zeal in science & wonderful powers of observation more than I do.— I venture to say this, as I feel myself a very old man, who probably will not last much longer.

Believe me, my dear Sir | Yours very sincerely | Ch. Darwin

P.S. With respect to Phyllanthus, I think that it wd. be good experiment to cut off most of the leaflets on one side of petiole, as soon as they are asleep & vertically dependent.— When the pressure is thus removed, the opposite leaflets will perhaps bend beyond their vertically dependent position; if not, the main petiole might be a little twisted so that the upper surfaces of the dependent & now unprotected leaflets shd. face obliquely the sky, when the morning comes. In this case diaheliotropism would perhaps conquer the ordinary movements of the leaves when they awake & resume their diurnal horizontal position.— As the leaflets are alternate & as the upper surface will be somewhat exposed to the dawning light it is perhaps diaheliotropism which explains your extraordinary case.7

Footnotes

See letter from Fritz Müller, 9 January 1881 and n. 7. Phyllanthus is the genus of leaf flower. See also letter to Nature, 22 February [1881].
Besides its unusual nyctitropic (sleep) movements, Müller had observed leaf movement during the day (paraheliotropism) in Phyllanthus niruri (see letter from Fritz Müller, 9 January 1881 and n. 8).
Müller had mentioned two forthcoming papers on fertilisation of figs, Solms-Laubach 1881 and Mayer 1882 (see letter from Fritz Müller, 9 January 1881 and nn. 13 and 15).
Caprification is the process of hanging clusters of wild fig (caprifig) flowers in edible fig trees in order to facilitate the transfer of pollen by fig wasps.
CD’s letter to Hermann Crüger of 18 March 1863 has not been found, but see Correspondence vol. 11, letter from Hermann Crüger, 23 April 1863. CD had suggested an experiment related to the fertilisation of figs. In his letter of 21 January 1864 (Correspondence vol. 12), Crüger reported that the experiment had failed. Although he had encased the fig flowers in cambric bags, insects had still managed to penetrate these. Crüger died in Trinidad on 28 February 1864; his last letter to CD was that of 21 January 1864 (see ibid., letter to J. D. Hooker, 25 April [1864] and n. 6).
CD had defined diaheliotropism as the taking of a position more or less transverse to the light and induced by it (Movement in plants, p. 5).

Bibliography

Mayer, Paul. 1882a. Zur Naturgeschichte der Feigeninsecten. Mittheilungen aus der Zoologischen Station zu Neapel 3 (1881–2): 551–90.

Movement in plants: The power of movement in plants. By Charles Darwin. Assisted by Francis Darwin. London: John Murray. 1880.

Solms-Laubach, Hermann. 1881a. Die Herkunft, Domestication und Verbreitung des gewöhnlichen Feigenbaums (Ficus Carica L.). [Read 3 December 1881.] Abhandlungen der Königlichen Gesellschaft der Wissenschaften zu Göttingen 27: 1–106.

Summary

CD interested by FM’s facts on movement of plants; has sent some to Nature ["Movement of leaves", Collected papers 2: 228–9]. Greatly admires FM’s work. Suggests an experiment to investigate movement in Phyllanthus.

Letter details

Letter no.
DCP-LETT-13064
From
Charles Robert Darwin
To
Johann Friedrich Theodor (Fritz) Müller
Sent from
Down
Source of text
The British Library (Loan MS 10 no 49)
Physical description
ALS 6pp †

Please cite as

Darwin Correspondence Project, “Letter no. 13064,” accessed on 16 April 2024, https://www.darwinproject.ac.uk/letter/?docId=letters/DCP-LETT-13064.xml

letter