RECORD: Darwin, C. R. 1867-1868.04. Cineraria Two plants purple vars were crossed reciprocally. CUL-DAR76.B97-B98. Edited by John van Wyhe (Darwin Online, http://darwin-online.org.uk/)

REVISION HISTORY: Transcribed by Christine Chua and edited by John van Wyhe 12.2022. 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 volumes CUL-DAR 76-79 contain material for Darwin's book Cross and self fertilisation (1876).


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Cineraria. 1867 Two plants, purple vars, were crossed reciprocally; & the head of both six in number, (about 8 having been crossed) produced an average of 41.3 seed per head with max. 53. — As the stigma gets covered with pollen, I expected to get self- & spont. fertilised seed, but I could not find any, & I carefully examined 24 flowers & not one seed. These 2 plants were then taken from under net & freely exposed to visit of bees in same hours with other plants & now plenty of seed were produced, especially on one of the two plants; for these plants show some tendency to be dioicous; some producing much pollen & few seeds; others conversely. Four flowers were repeatedly daubed with pollen from the same head; & one head yielded 2 good seed, & a second head yielded 8 very small seed, so small that I doubt whether wd. germinate. (Not one has germinated) Whilst plenty of crossed germinated

Then an experiment or 2 was repeated

(Another white-flowered & red-topped var had 2 fl. fertilised by a purple var. & the 2 heads produced 11 & 22 good seed. [Insertion:] [line illeg]

A multitude of flowers were well & repeatedly smeared with their own pollen, (& in all these cases I saw plenty of pollen on stigmas) & I doubt whether a single seed will germinate; in the best heads there were 4 or 5 which possibly may germinate. — (Not one has germinated) whilst plenty of crossed germinated.

Hence these 3 plants are absolutely sterile with pollen from same plant.— Perhaps only under culture.

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In April 1868. I se put 2 Plants under net, & crossed 3 fl. on one & 4 fl on other, but I did not get single seed, or any self-fertilised; so that this trial goes for nothing —


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

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