To J. D. Hooker   15 February 1878

Down, | Beckenham, Kent. | Railway Station | Orpington. S.E.R.

Feb 15. 1878.

My dear Hooker,

It is a grand idea to have old Sprengel translated. On the other hand I feel strongly opposed to the idea of the one work being published with the other. It would increase the price of H. Müller’s book which is admirable as containing all that is necessary for any one who wishes to pursue the subject.1 Moreover Müller would probably object to such a marriage; at least I should under similar circumstances.

The magnificent supply of Oxalis have arrived most of them safely. Besides experimenting on them with frost, if there ever is to be a frost again, I shall be particularly glad to observe the sleep of such odd forms.2

Seed of any south European species of Lotus would be valuable.

Thanks about the plumule of the nut.3 I do hope some of those which I have planted will germinate.

You seem to be quite right about the radicle: with the cabbage only the extreme tip bends over through geotropism4

Ever yours sincerely | Ch. Darwin

See letter from J. D. Hooker, 14 February 1878 and n. 1. Hooker had suggested that translations of Christian Konrad Sprengel’s and Hermann Müller’s books on fertilisation of flowers (Sprengel 1793 and H. Müller 1873) should be published in a single volume.
An entry dated 14 February 1878 in the Outwards book (Archives, Royal Botanic Gardens, Kew), p. 450, records that CD was sent Oxalis bupleurifolia (a synonym of O. fruticosa subsp. fruticosa, O. carnosa (a synonym of O. magellanica, fleshy sorrel), O. ortgiesii, O. plumieri (a synonym of O. frutescens, shrubby woodsorrel), O. rubella (a synonym of O. hirta, tropical woodsorrel), O. hirta, and O. pentaphylla (a synonym of O. polyphylla). For CD’s experiments with Oxalis left outside on frosty nights, see Movement in plants, pp. 287–9 and 293–7.
Hooker’s discussion of movement of the radicle, or embryonic root, was in a now missing section of his letter to CD of 14 February 1878; for CD’s observations of the radicle of the cabbage with respect to geotropism, see Movement in plants, pp. 512–13.

Please cite as “DCP-LETT-11360,” in Ɛpsilon: The Charles Darwin Collection accessed on 5 June 2025, https://epsilon.ac.uk/view/dcp-data/letters/DCP-LETT-11360