RECORD: Darwin, C. R. 1867-1868.06.26. Campanula speculum. CUL-DAR79.112. Edited by John van Wyhe (Darwin Online, http://darwin-online.org.uk/)

REVISION HISTORY: Transcribed by Christine Chua and edited by John van Wyhe 3.2023. 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 volumes CUL-DAR 76-79 contain material for Darwin's book Cross and self fertilisation (1876).


(90

Specularia Campanula speculum. 1867. Bad season

14 fl. crossed yielded 12 pods ie 86 per cent

20 fl. self-fert yielded only 6 pods ie 30 per cent; but this may be partly due to stigma being mature so long after pollen ready on collecting hairs & may possibly have gone bad or been insufficient.

The 12 crossed pods contained average of 30.0 seed with max. of 57 & min. of 4.

The 6 self-pods contained average of 21.7 seed with max of 48 & min of 5.

The 130 self seed weighed 0.50 gr ∴ 361 wd weigh 1.39 gr.

The 361 crossed seed weighed 1.62 gr. Therefore equal numbers of crossed & self seed weighed as 100 to 86.—

(May 10' 68 the self- seed in Pot IV sown thickly have germinated very badly.)

(May 24th 68 Plants 1 1/2 inch high & equal.)

(Jun 26 /68 In all 3 Pots the crossed have flowered considerably first)

[Table excised] very crowded; measured when dead I am not sure that I succeeded in measuring accurately, but I thought so — Did not set any seed. Difficult to self-fertilise.


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

File last updated 31 May, 2023