RECORD: Darwin, C. R. 1877.09.21. Radiation/ Trifolium resupinatum/ Cassia floribunda. CUL-DAR209.9.58. Edited by John van Wyhe (Darwin Online, http://darwin-online.org.uk/)
REVISION HISTORY: Transcribed by Christine Chua and edited by John van Wyhe 7.2022. RN1
NOTE: See record in the Darwin Online manuscript catalogue, enter its Identifier here. By 'radiation' Darwin means heat loss, a term he learned in Dr Hope's Chemistry classes in Edinburgh, "Heat is diffused by two ways conduction & radiation". CUL-DAR5.A6-A11. Reproduced with permission of the Syndics of Cambridge University Library and William Huxley Darwin.
The volume CUL-DAR209.9 contains materials for Darwin's book Movement in plants (1880).
[58]
Trifolium resupinatum / 77
Sept 21 The pot had been kept for 3 days in my study & was placed out of doors yesterday evening, which was very cold almost a frost.— A good many have had their edges slightly yellowed.— I gathered 10, & examined as opake object the terminal leaflets. 6 of them were distinctly yellower on the upper than on the lower surfaces: the remaining 4 differed little in this respect, but what difference there was seemed to be in the upper surface being yellower: now the terminal leaflet is generally turned over or stands vertically & this case seems to show that the upper surface is more injured by cold than the lower surface
Cassia floribunda— upper surface most blackened, was due to [illeg] over sky
(Radiation)
Citation: John van Wyhe, ed. 2002-. The Complete Work of Charles Darwin Online. (http://darwin-online.org.uk/)
File last updated 25 September, 2022