To J. D. Hooker   7 [April 1874]1

Down, | Beckenham, Kent.

7th

My dear H.

Perhaps Riley may have sent you the larvæ of the Pronuba moth so as to fertilise the Yuccas. As I have no plants, I forward them by this post to you, with his brief instructions.— It is the most wonderful case of fertilisation ever published.—2 Do try them, or give them away or throw them away.

Yours affect. | C. Darwin

We have asked Dr. Klein, Günther & Ld. Monteagle here for next Sunday,— Carriage at Orpington for 4o12’ Train on Saturday. Any hope of you?3

The month and year are established by the reference to a visit by Edward Emanuel Klein to Down House, and by the reference to Riley 1873 (see nn. 2 and 3, below).
Charles Valentine Riley described the pollination of Yucca, which occurs during oviposition of the yucca moth Pronuba yuccasella (now Tegeticula yuccasella), in Riley 1873. An offprint of Riley 1873 is in the Darwin Pamphlet Collection–CUL, and is annotated by CD: ‘Wonderful case of fertilisation, when the moth puts pollen on intentionally’. For more on the pollination mutualism of the yucca and yucca moth, see Pellmyr et al. 1996.
CD refers to Edward Emanuel Klein, Albert Günther, and Thomas Rice. Emma Darwin’s diary (DAR 242) records only Klein’s visit on Saturday 11 and Sunday 12 April 1874.

Please cite as “DCP-LETT-9395,” in Ɛpsilon: The Charles Darwin Collection accessed on 5 June 2025, https://epsilon.ac.uk/view/dcp-data/letters/DCP-LETT-9395