To William Robinson   5 May [1866]1

Down. | Bromley. | Kent. S.E.

May 5th

Dear Sir

I write one line to thank you & to say that it wd. be superfluous to castrate the flowers, which are crossed with pollen from a distinct plant, grown under as different circumstances as may be. The flowers fertilised with their actually own pollen shd. certainly be protected from insects.2

Dear Sir | yours much obliged | C. Darwin

P.S. I was glad to see your Election to Linn. Soc.—3

1
The year is established by the date of Robinson’s election to the Linnean Society (see n. 3, below).
2
Robinson’s letter has not been found; see, however, the letter to William Robinson, [29 April 1866] and nn. 4 and 6. CD had asked Robinson to make crosses of the waterlily Euryale ferox, and to compare the number of seeds in crossed individuals with that in self-pollinated specimens. CD asked for a similar experiment to be made with any species of Nymphaea, and instructed Robinson to protect the self-pollinated individuals from insects. Presumably it was not necessary to remove the anthers from the flowers because of the prepotency of the pollen from other individuals (see Cross and self fertilisation, p. 2).
3
Robinson was elected a fellow of the Linnean Society on 19 April 1866 (List of the Linnean Society of London 1866).

Manuscript Alterations and Comments

1.4 from insects] interl

Please cite as “DCP-LETT-5080,” in Ɛpsilon: The Charles Darwin Collection accessed on 5 June 2025, https://epsilon.ac.uk/view/dcp-data/letters/DCP-LETT-5080