Ɛpsilon

To John Lubbock   [before 17 September 1874]1

Sunday

My dear Sir John—

I enclose all that you require except Delpino on artemesia which is out of its place & I cannot find it.—2

I enclose copy of my M.S. on V. tricolor for my book, if I ever live to publish it, on benefits from crossing.3

I hardly know what plant to advise for seeing protrusion of pollen-tubes. Œnothera has very large grains. Mirabilis or Marvel of Peru the largest of all. The purple Convolvulus (or Ipomœa) wd not be bad.—4 Make a long slice of stigma after pollen has been on from 22o to 24o.—

Yours sincerely | Ch. Darwin

I did not think about Thrips5 when I wrote out 3 or 4 years ago my notes of V. Tricolor.—

I have read 2 other pamphlets on which I stumbled—

1
The date is established on the assumption that the letter relates to Lubbock’s two-part article in Nature, 17 and 24 September 1874 (see n. 2, below).
2
Federico Delpino had sent CD a copy of his ‘Studies in the anemophilous breeding of crosses in the group Artemisiaceae’ (Delpino 1871); see Correspondence vol. 19, letter from Federico Delpino, 15 November 1871). The family Artemisiaceae is now subsumed within the family Asteraceae. Lubbock referred to Delpino in an article on mechanisms to ensure cross-fertilisation published in Nature, 17 and 24 September 1874 (Lubbock 1874, p. 402), and in his popular book on the subject, British wildflowers considered in relation to insects, published in January 1875 (Lubbock 1875b, p. viii; Publishers’ circular 1875).
3
The enclosure has not been found; however, Lubbock quoted from a memorandum of CD’s observations on insects visiting Viola tricolor (heart’s-ease) in Lubbock 1875b, pp. 62–3. A modified version later appeared in Cross and self fertilisation, pp. 123–4. CDs draft manuscript for Cross and self fertilisation is in DAR 2–4; there are notes on Viola tricolor in DAR 79: 65–71.
4
Oenothera is the evening primrose; Mirabilis jalapa is the marvel of Peru; Ipomoea purpurea is the common morning-glory. CD’s extensive experiments on Ipomoea purpurea are described in Cross and self fertilisation, pp. 28ff.
5
Thrips or thunder-flies are in the order Thysanoptera.

Please cite as “DCP-LETT-9618,” in Ɛpsilon: The Charles Darwin Collection accessed on 5 June 2025, https://epsilon.ac.uk/view/dcp-data/letters/DCP-LETT-9618