From Asa Gray 21 June 1858
A word more about self-fertilization in Fumariaceæ 1 After the tips of the outer pair of petals have separated or turned back, it is easy enough for your coadjutors the bees (whom I have never yet noticed about a Fumariaceæ) to push the cap of the inner petals to one side and reach the stigma; this is especially easy in Dicentra spectabilis & Adlumia: But in both these plants, also in Corydalis glauca & C. aurea, I generally find pollen on the stigma before the outer petals have opened, and before any insect can intermeddle. In Dicentra this is most sure, because the cup-shaped tips of the outer petals fit exactly against the sides of the crest of the inner ones, shutting all up completely until they turn back; but by this time the work is done, commonly in D. spectabilis, et,— In D. formosa or eximia if not then yet very soon afterwards. The shedding of the pollen & the opening of the outer petals is here about simultaneous, as far as I have observed.
So I must still think, that the arrangement in Fumariaceæ is intended to secure self-fertilization.
Excuse my hasty note, and believe me, as ever | Yours cordially | Asa Gray June 21st, 1858
Self-fertilisation in Fumariaceae.
[CD note on bees’ visiting some members of Fumariaceae.]
Please cite as
Darwin Correspondence Project, “Letter no. 2288,” accessed on 17 January 2017, http://www.darwinproject.ac.uk/DCP-LETT-2288