RECORD: Darwin, C. R. [1872-1873]. ['On the movement of the leaves of Drosera'], folio ?. CUL-DAR61.13. (John van Wyhe ed., 2002-. The Complete Work of Charles Darwin Online, http://darwin-online.org.uk/)

REVISION HISTORY: Transcribed and edited by John van Wyhe 2.2026. RN1

NOTE: See record in the Darwin Online manuscript catalogue, enter its Identifier here. Reproduced with permission of the Syndics of Cambridge University Library and William Huxley Darwin. The volumes CUL-DAR 54-61 contain material for Darwin's book Insectivorous plants (1875).

The volume CUL-DAR61 contains Darwin's draft essay 'On the movement of the leaves of Drosera', written 1872-1873. He intended to publish this with a revised edition of Climbing plants before commencing a larger book draft in April 1874 which became Insectivorous plants. See the introduction to this essay by John van Wyhe.


[13]

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Leaves to have that The leaves certainly act differently according to the nature of the object placed on them. We have seen that when merely irritated the hairs after closing in promptly reexpanded in a far shorter time than when an insect has been caught; this was well shown when a fly was placed on one side of the leaf, & when the hairs on the other opposite side closed in free sympathy but say for these soon opened again.—    Whilst then over the fly remained closed for days.

In some instances the hairs clasped various substances objects within equal time; but I always found the substances, which contained ; for instance I put me [2 words illeg] a bits of raw meat, & then at the corners damp paper, bits of quill & moss on to several leaves & they were equally well enclosed embraced ½ in two hours; (but I always find the innutritious substances were released much sooner than flies or meat.  Damp wood is the [2 words illeg] which I tried as seemed to be retained longer than moss, paper or quill. but a greater number of experiments would be required to be sure of this.   Raw meat acted energetically but seemed too strong & generally injured the leaf & became mouldy. or even killed the leaf   In another case I put some flies & bits of quill, paper & moss & stuck on some leaves; the flies were clasped in a few hours, whereas, after 25 hours very few hairs were inflected over the other substances; I then put rather more on those same leaves, without removing the paper & moss,  -  minute bits of raw meat, & all the hairs in an [illeg] manner all clasped the meat [illeg] quickly & energetically completely, in one then they had done over the above named objects, —

Again I placed these bits of dry [illeg], & these (I concluded) must have weighed fully as much as the small flies,


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Citation: John van Wyhe, ed. 2002-. The Complete Work of Charles Darwin Online. (http://darwin-online.org.uk/)

File last updated 23 February, 2026