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Darwin Correspondence Project

To J. D. Hooker   19 September [1873]1

Down, | Beckenham, Kent.

Sept. 19th

My dear Hooker

I hope to receive tomorrow morning the Norton’s address, & will enclose it.—2 I am particularly obliged about the Mimosa albida: could not a cutting be struck for me? but that I suppose would take more time & this wd be bad for me.— If a vigorous plant behaves as you say my notions are all knocked on the head, & much time wasted.3 I am impatient to read Tyndall’s answer (& Nature has just come) to Taits petty attack.4

The story about Drosera is too long for my strength today; but essentially the leaves act just like the stomach of a mammal. The acid which is essential for digestion is not secreted until they are excited; but I must not go on.

Attend to this

Burdon Sanderson will give some grand facts at the Brit. Assoc. about Dionæa: he came here to see Drosera, as he was so surprised at what I told him.5

I will with pleasure give detailed instructions about experimenting on Nepenthes whenever you are ready; but you must get several reagents & doubly distilled water. If you fail in not having time I wd. undertake the job, & as I have everything ready & know what to do, it wd not take me much above a week or 10 days.6 Perhaps not so much; but I allways found that experimental work takes at least thrice as much time as I anticipated. I could keep Nepenthes for a time quite hot enough. You gave me years ago a Nepenthes, & it is still alive but very unhealthy, as it has been quite neglected.— I failed at that time from ill-health, when I thought of attacking it. Desmodium gyrans is throwing out new leaves splendidly7

My dear old fellow | Ever yours | Ch Darwin

P.S. The address has not come, but I am certain that

“Charles Norton Esq



U. States”

will reach him.—

Could you anyhow spare time to come down here some Sunday soon.— I want much your advice on a family subject.8 And secondly I could give you better by talking than by writing all the suggestions for Nepenthes, which I have learnt by working on Drosera & Dionæa; not but what you could after a time have found out all & more I daresay.

Ch. D.

But I must not talk so much as I did on that last Sunday.9

I am extremely glad to hear about G. Henslow.—10


The year is established by the relationship between this letter and the letter from J. D. Hooker, 16 September 1873.
Hooker had asked CD for Charles Eliot Norton’s address (see letter from J. D. Hooker, 16 September 1873 and n. 9). The Nortons lived at Shady Hill, their family estate in Cambridge, Massachusetts (see ANB).
CD was investigating the circumstances in which Mimosa plants closed their leaves (see letter to Francis Darwin, 15 August [1873] and n. 10). Hooker had informed him that Mimosa albida had a sluggish reaction to being touched (see letter from J. D. Hooker, 16 September 1873).
For the dispute between John Tyndall and Peter Guthrie Tait in Nature, see the letter from J. D. Hooker, 16 September 1873 and n. 4.
CD had described the digestion of Drosera (sundew) in the letter to J. S. Burdon Sanderson, 27 August 1873. John Scott Burdon Sanderson visited CD at Down on 4 July 1873 (Emma Darwin’s diary (DAR 242)). He presented his paper ‘On the electrical phenomena which accompany the contractions of the leaf of Dionæa muscipula’ (Burdon Sanderson 1873a) at the British Association for the Advancement of Science meeting held at Bradford from 17 to 24 September 1873.
Hooker intended to experiment on Nepenthes, the tropical pitcher-plant, in the same way that CD had experimented on the carnivorous plants Drosera and Dionaea muscipula (Venus fly trap) (see letter from J. D. Hooker, 16 September 1873 and n. 8, and J. D. Hooker 1874a).
Desmodium gyrans (now Codariocalyx motorius) is a tropical plant capable of movement. It has small leaflets that constantly move; it is now believed that is to assess the best position for the larger leaves to assume in order to maximise the amount of sunlight they receive.
CD probably wanted to discuss Francis Darwin’s wish to become CD’s botanical secretary (see letter to E. A. Darwin, 20 September 1873).
CD had invited Hooker and Richard Strachey to visit Down from the evening of Saturday 23 August until the following Monday morning (see letter to J. D. Hooker, 4 August [1873]); they arrived on 23 August (Emma Darwin’s diary (DAR 242)).
George Henslow was recovering from a serious illness (see letter from J. D. Hooker, 16 September 1873 and n. 5).


Obliged for information on Mimosa albida; if a vigorous plant behaves as JDH says, CD’s notions are all knocked on the head.

Anxious to read Tyndall’s answer to Tait [Nature 8 (1873): 399].

Drosera story too long for his strength. Essentially the leaves act just like stomach of an animal.

Burdon Sanderson will give some grand facts at BAAS about Dionaea.

Offers to help JDH with Nepenthes experiments. Finds experimental work always takes twice as much time as anticipated.

Letter details

Letter no.
Charles Robert Darwin
Joseph Dalton Hooker
Sent from
Source of text
DAR 95: 277–9
Physical description

Please cite as

Darwin Correspondence Project, “Letter no. 9059,” accessed on 26 March 2019,

Also published in The Correspondence of Charles Darwin, vol. 21