RECORD: Darwin, C. R. 1873.01.28-10.12. Pelargonium. CUL-DAR55.78. Edited by John van Wyhe (Darwin Online, http://darwin-online.org.uk/)

REVISION HISTORY: Transcribed by Christine Chua and edited by John van Wyhe 1.2023. 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).


[78]

Pelargonium

Jan. 23d /73/ I placed leaf of white zoned Geranium for 2 hours in sol. of 3 gr. Ni. of Ammonia to 1 oz. & I think that the heads of shorter Hairs had all become opake.

Movement of Protoplasm

I also placed a bit in a weak infusion of raw meat. — Almost all the heads of shorter hairs now contained spheres — 1- to 4 or 5 of yellowish matter. — I watched one of these, which 4 speres & after 1 or 2 hours, one of them divided into 2 small ones.— But these movements are not like those of the protoplasm in Drosera. —

Best plan wd be to remove little bit of upper lamina of leaf, & it wd then be transparent enough to see whether the head of glands were transparent & then look for 3 hour in juice of meat & see if they become opake.— (over)

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Oct 12th /73/ put on drop of weak infusion of raw meat at 8˚12'— examined the hairs at 10 40' — there were many spheres within the spherical heads of Hairs, & these often above 1/2 hour slightly changed position & form, but then those with spheres in the hairs on low under side of leaf which had not been immersed─ I think not so plain but case not to be trusted. —


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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 14 May, 2023