The Complete Work of Charles Darwin Online

RECORD: Darwin, C. R. 1878.04.04. Canary grass — Cotyledons Apogeotropism. CUL-DAR209.11.91. (John van Wyhe ed., 2002-. The Complete Work of Charles Darwin Online, http://darwin-online.org.uk/)

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-DAR209.11 contains material for Darwin's book Movement in plants (1880).

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Canary grass — Cotyledons. Apogeotropism

April 4th 1878. Glass filament affixed— pot laid horizontally [sketch] traced on vertical glass illuminated in front only when observations taken. Two seedlings young. —Began to rise at once. By 2º cotyledons very much curved upwards— First observation at 8º. 50 (ie in about 5º) — Apparently after 9º & 5º circumnutation was commencing.— Till then very little signs of do, for they rose up remarkably straight . By 5º P.m many of the seedlings parallel to surface of pot, so had curved up through 90' in 8º or less.

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