RECORD: Darwin, C. R. 1878.06.27-07.14. Gourd / Lagenaria clavæformis. CUL-DAR209.4.191-192. Edited by John van Wyhe (Darwin Online, http://darwin-online.org.uk/)
REVISION HISTORY: Transcribed by Christine Chua and edited by John van Wyhe 9.2022. 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 volume CUL-DAR209.4 contains materials for Darwin's book Movement in plants (1880).
[191]
Gourd
Sleep of Cotyledons
1878
"New (Thompson) Miniature Bowl Bottle Gourd"—
On 27' Cots first slightly opened, & closed at night.
On 28' one seedling (2 Pins) had 2 cots forming together an angle of 53°; at 10° P.m their tips touching, but not whole surface, as one was crumpled, but the flat one stood upright.
On 29th at 3° P.m the 2 Cots formed angle of 118° at 10° P.m, angle was 54°, so each Cot had risen 32°
With A second seedling (2 sticks) the 2 cots stood by day at 68° together & at 10° P.m at 14°, so angle had decreased by 54° & each had risen 27°.
On 29th at 3° P.m. the 2 cots formed angle together of 118°, & at 10' P.m the angle was 54°, so each had risen 32°.—
It is pretty clear that in this case the closing at night during first 2 days is merely that cots rise at night, but that during first few days of life they do not fully expand.) The w petiole is so short as can hardly not be said to exist, & I am almost sure whole Cot. curves up & down — (so with Trifolium the terminal leaflet curves over)— not odd as petiole & mid-ribs are continuous.
(June 30th)
Lagenaria clavæformis: in a seedling Cot at 12° 30 49° apart at 10° P.m. they were only 4° apart, & both to the eye looked vertical so each had risen 22° 30"— The 2d seedlings they were at 12° 30' only 35° apart & at 10° P.m about 10' apart, so had risen consi less.—
Tip of Cots. a little reflexed, so these observations relate only to the main & lower length of Cots.
[192]
Little Bottle Gourd (seed from Thompson)
(Circumnutation of Cotyledons & sleep of) July 11th to 14th 1878
Cotyledon 1 1/2 inches long — tip 4 3/4 from vertical glass — Stem secured to stick observed under skylight— (Temp. on 11th & 12th & 13th 17 1/2 to 18°C.) [sketch]
See Tracing..
The Cotyledon opened fully on the 10th & were first observed on 11th
During first night i.e 11th become at 8° 40' quite vertical & so cd not be marked, having simply risen all day after 10° a.m.
On next day (12th) plainly circumnutated & rose considerably at night, but never stood quite vertical.— fell during night & on 13th again circumnutated a little, but at night did not rise late in evening & fell during night, rising next morning. So on night of 13th all signs of so-called sleep lost.—
Perhaps light & Heat not sufficient
Citation: John van Wyhe, ed. 2002-. The Complete Work of Charles Darwin Online. (http://darwin-online.org.uk/)
File last updated 27 September, 2022