RECORD: Darwin, C. R. n.d. [Abstract of Robert Brown, On the organs and mode of fecundation in Orchidiæ and Asclepiadeæ, 1833]. CUL-DAR74.173-174. Edited by John van Wyhe (Darwin Online, http://darwin-online.org.uk/)

REVISION HISTORY: Transcribed by Christine Chua and edited by John van Wyhe 8.2021. 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 volumes CUL-DAR 72-75 contain Darwin's abstracts of scientific books and journals.

Robert Brown. 1833. On the organs and mode of fecundation in Orchidiæ and Asclepiadeæ. Read 1 and 15 November 1831. Transactions of the Linnean Society of London, vol. 16: 685-745.

[173]

R. Brown

p 689 Where does J. Hunter use expression of "male principle of arrangements."

p 704 in note does not allude to some seeds in spikes in Cruciferæ not being impregnated. Has he ever seen a cone in monoecious or dioecious, as maize plant with all impregnated.

p 726 Is it generally case with Asclepias that pollen-masses have been moved - ie or do they seed freely.

p 727 Does it require force to remove pollen-mass from cone

730 does Hoya carnosa seed does not know - should think not.

731 On what part of insect does gland adhere: seen dead bee on Asclepias, covered with anthers & glands

p. 732 speaks of pollen-tubes having been seen in Viola. - must pollen-grains enter hollow stigma? Yes it is - does not know precise means of impreg. asked whether stigma does not bend to anthers?

704. Was the Orchis in which every stigma was impregnated in spike one of those wh. requires insects Yes

[173v]

No Asclepias introduced into England is annual

[174]

Hunter's expression is quoted in note in 2d. Edition of Witherings Bot. 1787

Sprengel has written rare book on impregnate of flowers by insects

Did not answer me how many seeds in spike of maize are impregnated - difficult to know without close dissection or growth & then one does not know whether not like 'aphis'-case

Asclepias do not seed freely - there is one [stone] species, which he never found with seed except one plant at Covent Garden which he heard had been carried out to some route where doubtless some insect effected it

The tube of Orchis' mentioned (like insects) may be impregnated by [illeg] or by wind acting on swinging pollen masses: seems to think strongly that insects on these are injurious

(a)

[174v]

all I can say against this will be shown that bees do visit Ophrys. = strongest fact against intermarriage theory = show bees guided by smell & not sight. =

J. Hunter says in unpublished lectures Urethra does two things badly:

Most masses have beautiful structure to disperse seeds

Christian Konrad Sprengel in 1793 on 4to. German book I believe entitled Entol. Geheim on action in insects in impregnation —


Return to homepage

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

File last updated 25 September, 2022