RECORD: Darwin, C. R. 1846.10. It is never to be lost sight of whether characters are drawn from embryonic parts, as in plants, where there is no special adaptations. CUL-DAR205.6.38. Edited by John van Wyhe (Darwin Online, http://darwin-online.org.uk/)
REVISION HISTORY: Transcribed by Christine Chua and edited by John van Wyhe 11.2021. 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-DAR205.6 contains notes on embryology [pigeons].
The brown crayon number '12' indicates that this document was filed by Darwin in his portfolio for the subject of Embryology.
Oct. 46 (12)
It is never to be lost sight of whether characters are drawn from embryonic parts, as in plants, where there is no special adaptations - or from other adapted parts - central organs bear some relation to embryonic in this respect. Embryos which have free life as caterpillars - or external parts in every embryo (as hooks &c &c) may vary.
On this review the variation of important
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parts, as position of embryo in Helianthemum, becomes almost a difficulty no - it is in state of transition. For these transitions we must not look to all the contemp species of a genus but to a long lineal succession. That case of same seed having suspended & other embryo, shows how change may sometimes be affected suddenly.
As some organs, (as horns) do not appear till late, though hereditary, they must be affected late in life
Citation: John van Wyhe, ed. 2002-. The Complete Work of Charles Darwin Online. (http://darwin-online.org.uk/)
File last updated 25 September, 2022