To C. W. Crocker 1 June [1861]1
Down. | Bromley. | Kent. S.E.
June 1st.
My dear Sir
Pray do not in the least hurry yourself: any time will do for me, & I shall much value your information. I do not quite understand whether you are thinking of a general course of scientific experiments in crossing or only in relation to Hollyhocks.— I am pretty confident there is a fine open field for research in regard to crossing varieties which have been greatly neglected under a scientific point of view, though largely & loosely practised by gardeners. Species on the other have been largely experimented on. As you have lived so much abroad, German is probably quite familiar to you2 (I wish it were to me) & I would most strongly advise you to get Gärtners admirable “Versuche ueber die Bastardzeugung. 1849” & study it.—3 If ever you thought of taking up scientifically the subject of crossing & feel that you have indomitable patience, I would beg permission to make a few suggestions on experiments, which I would surely have tried, had time & health permitted.—
With hollyhocks, I think it would be very useful to ascertain the effects of crossing, especially of those varieties which commonly breed true. You probably know far better than I; but when I tried I castrated these flowers in bud, but I believe it would quite suffice to remove anthers before the stigmas expand; & then cover the flower with gauze or net.— It would be extremely interesting to test following point; impregnate a dozen flowers of, we will say, a yellow Hollyhock (if that kind breeds true) with a black or some widely different kind; & then fertilise 12 of the yellow flowers with pollen of yellow flowers from another plant, performing every manipulation the same to the two sets; & then observe whether any difference in number of seed, which ought to be Counted or weighed. This experiment wd. be very interesting on account of a wonderful statement on this head by Gärtner with respect to crossing white & yellow Verbascum.4
Are you a fancier of Pelargoniums? I could suggest some interesting experiments; but I must not run on.— Pray excuse me, & believe me— | My dear Sir | Yours very sincerely | C. Darwin
Footnotes
Bibliography
Gärtner, Karl Friedrich von. 1849. Versuche und Beobachtungen über die Bastarderzeugung im Pflanzenreich. Mit Hinweisung auf die ähnlichen Erscheinungen im Thierreiche, ganz umgearbeitete und sehr vermehrte Ausgabe der von der Königlich holländischen Akademie der Wissenschaften. Stuttgart: E. Schweizerbart.
Variation: The variation of animals and plants under domestication. By Charles Darwin. 2 vols. London: John Murray. 1868.
Summary
Suggests procedures for breeding experiments with hollyhocks. Recommends C. F. v. Gärtner [Bastarderzeugung (1849)]. [See also 3151]
Letter details
- Letter no.
- DCP-LETT-3170
- From
- Charles Robert Darwin
- To
- Charles William Crocker
- Sent from
- Down
- Source of text
- American Philosophical Society (Mss.B.D25.251)
- Physical description
- ALS 6pp
Please cite as
Darwin Correspondence Project, “Letter no. 3170,” accessed on 29 March 2024, https://www.darwinproject.ac.uk/letter/?docId=letters/DCP-LETT-3170.xml
Also published in The Correspondence of Charles Darwin, vol. 9