RECORD: Darwin, C. R. 1862.06.01-29. Rhexia glandulosa. CUL-DAR205.8.14-15. Edited by John van Wyhe (Darwin Online, http://darwin-online.org.uk/)

REVISION HISTORY: Transcribed by Christine Chua and edited by John van Wyhe 4.2022. 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 volume CUL-DAR205.8 contains notes on the genus Monochaetum and other plants.


[14]

June 1 62 Rhexia glandulosa Kew

Sepal faces with connective fork perhaps a trace larger & less deeply divided, no difference in the two pollens. Petal faces with arms of fork thinner & longer – Both same coloured & tipped with yellow. (Later in summer unprotected set a few pods)

Pistil stands in middle of flower with tip rectangularly bent, & all 8 anthers are curved & converge towards tip of 1 stigma, but not the middle of flower, but to the side towards which tip of stigma is bent: hence the stamens on one side of flower incline backwards.

The forks of both sets of stamen point nearly upwards in line of filament & doubt whether of any service, except possibly to prevent bowed anther being pushed too much down. – over

[annotated sketch]

[14v]

June 1 fertilised one with pollen of long-fork (petal faces) marked white bobbin.

June 4 fertilised one with pollen of long-fork (petal f) white bobbin

- one with pollen of short-fork (sepal faces) black worsted X

6 – do do do do X

7 one white Bobbin/ 1 black worsted X

12 - white Bobbin [crossed] (one broken off not to be counted)

13 Black worsted X

20 Black worsted X a thin marked

(1 [illeg] ) means unfertilised flower: a second marked I am sure there were one or 2 other flowers not fertilised

23d White Bobbin X

25 2 black worsted XX 1 white Bobbin X

29 Black worsted XX

- Both pollen – Black & white. July 2d do. – (5 white 8 Black 1 white & Black

Jun 4 one flower of Heterocentron mexicanum opened since yesterday & pistil no quite rectangular. – fertilised with pollen of yellow anther white thread

[15]

Rhexia glandulosa

8 flowers fertilised (Black worsted) with pollen from sepal facing stamens with short fork; all produced capsules, but one small.

5 flowers fertilised (white Bobbin) with pollen of petal-facing stamen with long fork; 4 produced capsules.

2 flowers fertilised with both pollen both produced pods; – but did not produce any extra quantity of seed. On whole rest of large plant with many flowers & open to insects in garden, only 2 or 3 pods were produced.

7 Pods of sepal-faces contained 4.1(+) gr. weight of seed

4 Pod of petal faces contained 2.6(-) gr. weight of seed.

By this in proportion the 7 pods fertilised by sepal faces ought to have had 4.5 gr. they did have rather above 4.1; so that may safely said both pollen produce equal quantity of seed.


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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 25 September, 2022