skip to content

Darwin Correspondence Project

To Federico Delpino   14 October 1869


Oct. 14. 1869

Dear Sir

I am much obliged for your courteous and interesting letter.1 I write now in case you should publish on Coryanthes, to caution you to consult a paper in the Bulletin de la Soc. Bot. de France, Tom. 2. 1855. p. 351, in which you will see that the fluid in the labellum hardly deserves to be called nectar.2 I believe Crüger to be right, and I send his paper in case you have not seen it.3

I have been very much struck by the originality of many of your remarks in one of your papers formerly sent; I do not remember the title, and I have lent all your papers to Mr. Farrer who has been studying the Leguminosæ and writes enthusiastically about your papers.4 I have long believed that humming birds play a great part in the fertilisation of many American flowers such as Salvia, Fuchsia &c. From enquiries which I made at the C. of Good Hope I believe that Strelitzia is fertilised by honey-suckers (Nectarinæ). I have received your two papers and hope to get parts of both translated for my own reading.5

If the editor does not send the succeeding numbers of “Scientific Opinion”, I will send them to you if you will inform me.— I am not satisfied with the remarks which I have made on the re-growth of limbs.6

Permit me to suggest to you to study next spring the fertilisation of the Gramineæ; I feel sure that those botanists are wrong who assert that the fertilisation takes place in the flower-bud; though I suspect this occasionally takes place in Triticum. Zea mays would be well worth studying.7 A Swedish book very much like Hildebrand’s has just appeared, so our subject is receiving much attention; I cannot give you the title as I have lent it to Mr. Farrer.8

Believe me, dear Sir | with much respect | Yours very faithfully | Charles Darwin


The article referred to included a report on an analysis of the fluid in the Coryanthes ‘bucket’ that determined that it was mostly water with a small percentage of mucilaginous compounds (Menière 1855, p. 354).
CD refers to Hermann Crüger and Crüger 1864.
CD sent several of Delpino’s works to Thomas Henry Farrer (see letter from T. H. Farrer, 9 October 1869 and n. 2).
See letter from Federico Delpino, 9 October 1869 and n. 8. The final two instalments of Delpino 1869b appeared in the 6 October and 13 October 1869 issues of Scientific Opinion. CD mentioned Delpino’s review and criticisms in Variation 2d ed., 2: 350 n. 1, and 380–1. For CD’s remarks on the regrowth of limbs in response to Delpino 1869b, see the letter to Scientific Opinion, [before 20 October 1869]. For CD’s original remarks on regrowth of limbs, see Variation 2: 376–7.
Triticum (wheat) and Zea mays (maize or sweetcorn) are members of the grass family, Gramineae (now Poaceae).
CD refers to Friedrich Hildebrand and Hildebrand 1867a, and to Johan Severin Axell’s Om anordningarna för de fanerogama växternas befruktning (On the mechanisms for the fertilisation of phanerogamic plants; Axell 1869).


Axell, Severin. 1869. Om anordningarna för de fanerogama växternas befruktning. Stockholm: Iwar Hæggströms Boktryckeri.

Crüger, Hermann. 1864. A few notes on the fecundation of orchids and their morphology. [Read 3 March 1864.] Journal of the Linnean Society (Botany) 8 (1865): 127–35.

Menière, Prosper. 1855. Note sur la sécrétion d’un liquide abondant par l’organe glanduleux des Coryanthes. [Read 11 May 1855.] Bulletin de la Société Botanique de France 2: 351–5.

Variation 2d ed.: The variation of animals and plants under domestication. By Charles Darwin. 2d edition. 2 vols. London: John Murray. 1875.

Variation: The variation of animals and plants under domestication. By Charles Darwin. 2 vols. London: John Murray. 1868.


Cautions FD about fluid in labellum of Coryanthes.

T. H. Farrer is enthusiastic about FD’s papers.

Believes humming-birds fertilise many American flowers.

Mentions his reply to FD’s criticisms ["Pangenesis: Mr Darwin’s reply to Professor Delpino", Sci. Opin. 2 (1869): 426; Collected papers 2: 158–60].

Suggests that FD study fertilisation of Gramineae.

Letter details

Letter no.
Charles Robert Darwin
Federico Delpino
Sent from
Source of text
DAR 143: 379
Physical description

Please cite as

Darwin Correspondence Project, “Letter no. 6938,” accessed on 24 January 2021,

Also published in The Correspondence of Charles Darwin, vol. 17