To Daniel Oliver   18 March [1864]1

Down. | Bromley. | Kent. S.E.

Mar 18

Dear Oliver

I am extremely obliged to you for your two letters.2

Your first letter was just what I wanted & I greatly prefer being treated as what I am[:] quite ignorant of the rudiments of botany.3

Your information about Tecoma tho’ chiefly negative is of value as it will save me much useless labour.4 Thank you much for tell me of the book on orchids which I have not seen. I have been pleased & interested by the extracts tho’ we are such bad German scholars we have had hard work to make them out.5 I can hardly believe the statement about Catasetum.6 I have no doubt from facts communicated to me that Cat. Tridendatum does sometimes seed in its native country, & that there is great difference in the degree of separation of the sexes.7 About the sexes of Acropera I certainly erred, but it is a wonderful mystery how the plant can be naturally fertilised in its native country8

You must not think of wasting yr time in telling me any thing more about the book; unless indeed you come across anything very important; but I hope that perhaps you will review it.9 Please to tell Hooker that the magnificent supply of plants is arrived safely & I thank him sincerely.10

I am dear Oliver | yours sincerely | Ch. Darwin

LS

1
The year is established by the relationship between this letter and the letters from Daniel Oliver, 12 March 1864 and [17 March 1864].
3
In the postscript to the letter from Daniel Oliver, [17 March 1864], Oliver apologised for the tone of his letter of 12 March 1864.
5
CD refers to Beer 1863, which he had inquired about in 1863 (see Correspondence vol. 11, letter to J. D. Hooker, 23 [June 1863]); Oliver probably discussed it in a missing portion of the letter from Daniel Oliver, [17 March 1864], and enclosed extracts.
6
For Joseph Georg Beer’s claim to have successfully pollinated Catasetum, see Beer 1863, pp. 22–3. In the second edition of Orchids, p. 197 n., CD referred to Beer 1863, p. 22: ‘during three years he [Beer] tried in vain to fertilise Catasetum, but on one occasion, by placing only the viscid disc of a pollinium within the stigma, a ripe fruit was produced’. CD then added: ‘but it may be asked, Did the seeds contain embryos?’. He believed that C. tridentatum (a synonym of C. macrocarpum, the jumping orchid) was the male form of an orchid that also had female and hermaphrodite forms (see letter from Hermann Crüger, 21 January 1864 and n. 17, and letter to Daniel Oliver, 17 February [1864]). See also CD’s notes on Beer 1863 in DAR 70: 150 and 155.
7
CD may refer to Edward Bradford’s observation of Catasetum in Trinidad (see Correspondence vol. 11, letter from Edward Bradford, 31 July 1863, and letter from H. F. Hance, 10 May 1863, and ‘Fertilization of orchids’, p. 154 (Collected papers 2: 151)); however, see also letter from Hermann Crüger, 21 January 1864, and Crüger 1864. CD had wondered for some time whether the pollination of many tropical and subtropical orchids was affected by their cultivation away from their native habitat (see, for example, Correspondence vol. 11, letter to P. H. Gosse, 2 June [1863]). However, he eventually expressed doubt that this was the case with Catasetum (see Orchids 2d ed., pp. 197 n., 198). In Orchids, p. 265, he discussed the effect that a change of environment could have on sterility. For differences in the sexes of Catasetum, see letter to Daniel Oliver, 17 February [1864] and nn. 6–8.
8
In Orchids, pp. 203–10, CD had described Acropera as dioecious, concluding that the specimens he examined were male; however, John Scott succeeded in pollinating flowers with pollen from the same plant (see Correspondence vol. 10, letter from John Scott, 11 November 1862). CD also eventually pollinated Acropera (see Correspondence vol. 11, letter to John Scott, 7 November [1863] and n. 6, and the experimental note in DAR 70: 114). CD mentioned his error in ‘Fertilization of orchids’, p. 153 (Collected papers 2: 150), and Orchids 2d ed., p. 172. A note of CD’s in DAR 70: 150 mentions that Beer too had trouble pollinating Acropera, but that it easily produced seed; Beer wrote (Beer 1863, p. 22) that artificial pollination of Acropera was difficult but was achieved by cutting the pollen-mass into pieces before insertion. Both Catasetum and Acropera are native to tropical and sub-tropical America.
9
No review by Oliver of Beer 1863 has been found. CD later borrowed the book from Joseph Dalton Hooker (see letter to J. D. Hooker, [5 August 1864] and n. 6).
10
Hooker had sent CD a new supply of climbing plants (see letter from J. D. Hooker, 16 March 1864).

Please cite as “DCP-LETT-4430,” in Ɛpsilon: The Charles Darwin Collection accessed on 5 June 2025, https://epsilon.ac.uk/view/dcp-data/letters/DCP-LETT-4430