RECORD: Darwin, C. R. 1878.09.21-10.28. Lychnis githago. CUL-DAR209.14.35. Edited by John van Wyhe (Darwin Online,

REVISION HISTORY: Transcribed by Christine Chua and edited by John van Wyhe 7.2023. 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 volume CUL-DAR209.14 contains material for Darwin's book Movement in plants (1880).


1878 Lychnis githago.

Sept 21 The first pair of small true leaves was open in morning & closed at vertically upwards exactly like Cotyledons; & this morning (22d) at 6° 45' a.m, they were again open. (—First case of true leaves behaving like cotyledons. — I suppose they are cotyledons?) What a contrast to Sida!

Sept. 25' 10° 15' P.m. The cots; are not at all asleep; But the first true leaves of 1 seedling (marked with bits of stick) which at 12° 30 at formed together an angle of 62° at 10° 15 formed angle of only 8°, so each cot leaf had risen 27°— with a second seedling (marked with pin) the cots leaves did formed at 12° 30 angle of 70°, at night only 8°, so each had risen 31°— 90 [-] 35 [=] 55

[in margin:] I have ascertained what I here called cotyledons are really so

Sept 30th This 2d pair of leaves at 4° 15' formed angle together of 96°, & at 10° P.m of 69°, but this rise not sufficient to give appearance of sleep.— The angle third & young pair of leaves at same hour was 20° & at night only 5° & then on all the young plants appeared asleep. — (over


Oct 6. The third pair of true leaves of good size at noon formed together angle of 20°—; at 10° P.m. quite closed & vertical— A pair of small leaves within (4th pair of true leaves) were a little open at noon & closed at night.—

Oct. 28 The 6th pair of leaves stood formed together at noon angles of 21° & at 9° P.m were closed except divergent tips; these tips at noon were 1.04 inch apart, & 9° P.m only .43 of inch apart.— In another plant, with a 6th pair of very young leaves I cd perceive no difference at noon & night.

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Citation: John van Wyhe, ed. 2002-. The Complete Work of Charles Darwin Online. (

File last updated 17 August, 2023