RECORD: Darwin, C. R. [ny].09.03.-12. Drosera anglica or some var of longifolia. CUL-DAR60.1.123-125. Edited by John van Wyhe (Darwin Online, http://darwin-online.org.uk/)

REVISION HISTORY: Transcribed by Christine Chua and edited by John van Wyhe 12.2022. 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).


(1

Drosera Anglica a rare Var. of longifolia. or sp.

The Leaves much elongated gradually widening upwards from footstalk to tip, which is rounded or bluntly pointed. — I could perceive no difference in action from D. longifolia.

Sept. 3d. Part of fly put on middle of 3 leaves, inflection slow, but now after 24°, no marginal inflection of leaf, but the tip bent down of on fly, even on one part fly placed near to base of leaf, into a hook-shape — so that the extremity had passed through 180° — in 2 of the leaves every tentacle inflected one f the flies now humid with secretion — (Atoms of quite dry meat placed on glands caused plain movement in 1' or 1' 30'—

In one of these tentacles after 1° 10' great inflection, which carried to centre of leaf, & purple fluid all aggregated into lumps in whole upper part of the tentacles.

Touched several 1/2 dozen times with needle glands of 3 marked tentacles; one of them in 17' well inflected, & in 24° was straight again the 2 others never moved.

[1v]

(Secretion acid)

(2

D. Anglica Sept 3d at 8° 46' put on 2 bits of boiled cork, 1 of boiled Thread, 2 of cinder from fire. — 2 scales of Sphagnum had previously apparently lately fallen on 2 glands— in After 8° 45', one bit of cinder & the 2 scales of sphagnum had caused inflection.

Next morning after 23° 15', both the 2 cinders, the one of the 2 corks, & the thread had all caused some inflection, ie 4/5 of particles had acted, not containing the sphagnum

The tentacles with scale of sphagnum had become straight again. —

Examined one of much inflected tentacles; the inflection is near base; the concave side very pale purple middle darker, & convex darkest side: but in another straight tentacle, not acted on by meat meat, the colour was similarly distributed, so that this seems the natural colouring & it makes me doubt about the common Drosera.

The convex outline of convex side of the tentacle with meat looked straight more rigid than the out-line of concave side. — Carb. of ammonia cause. great segregation — It lessens the purple tint on both convex & concave sides.

[2v]

Sept 12' D. Anglica old leaf 1.1 long & only 2 of inch broad.


Return to homepage

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

File last updated 14 February, 2023