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Darwin Correspondence Project

To J. D. Hooker   30 May [1862]1


May 30th

My dear Hooker

Infinite thanks for 3 grand plants of Melastomas;2 if anything can be safely made out, I have now good opportunity. I saw again today the 2 sets of plants of Heterocentron raised from the two pollens from same flower, & you never could imagine what a marvellous difference in stature.3 Also many thanks for Vanilla:4 it is very different indeed from any orchid which I have seen, & has pollen like Cypripedium(!) & very curious stigma. But oh Lord what will become of my book on Variation:5 I am involved in a multiplicity of experiments.— I have been amusing myself by looking at the small flowers of Viola. If Oliver has had time to study them,6 he will have seen the curious case (as it seems to me) which I have just made clearly out, viz that in these flowers the few pollen-grains are never shed or never leave the anther-cells, but emit long pollen-tubes, which penetrate the stigma. Today I got the anther with the included pollen-grains (now empty) at one end, & a bundle of tubes penetrating the stigmatic tissue at the other end; I got the whole under the microscope without breaking the tubes: I wonder whether the stigma pours some fluid into the anther so as to excite the included grains. It is a rather odd case of correlation that in the double sweet Violet, the little flowers are double; i.e. have a multitude of minute scales representing the petals. What queer little flowers they are.—7

Have you had time to read poor dear Henslow’s life:8 it has interested me for the man’s sake, & what I did not think possible, has even exalted his character in my estimation. But I much fear that the Public will think it dull. It will, however, be useful to any clergyman trying to follow, longo intervallo, Henslow’s footsteps.—

How bothered with visitors & hard worked you are.9

Good Night | Charles Darwin

P.S. Tell Oliver, I think he must by mistake, when I asked him, have opened the ovarium of female Lychnis dioica: anyhow I can find no vestige of ovules—10 Tell him that my fancied dimorphisms, like that of Primula, of Oxalis acetosella is all a confounded mistake; only great variability in length of pistils.—11

I have just looked again at V. canina—the case odder;12 only 2 stamens which embrace the stigma have pollen; the 3 other stamens have no anther-cells & no pollen.— These 2 fertile anthers are of different shape from the 3 sterile others; & the scale representing lower lip is larger & differently shaped from the 4 other scales, representing 4 other petals.—

In V. odorata, (single flower) all 5 stamens produce pollen. But I daresay all this is known.—


The year is established by the reference to Jenyns 1862 (see n. 8, below).
CD refers to the account of variation in domesticated plants and animals (Variation) that he had begun to prepare in January 1860 after the publication of Origin. He suspended work on Variation in July 1861 to produce Orchids, and, because of ill health, had only recently turned his attention once more to Variation (see Correspondence vols. 8 and 9, and ‘Journal’ (Correspondence vol. 10, Appendix II)).
Daniel Oliver had talked of including an account of dimorphism in Viola in his review of ‘Dimorphic condition in Primula ([Oliver] 1862c) (see letter from Daniel Oliver, 10 April 1862). See also letters to Daniel Oliver, 12 [April 1862] and 15 April [1862].
There are notes by CD on his experiments with Viola in DAR 111: 3–5, dated 28 May and 30 May 1862.
Jenyns 1862. John Stevens Henslow, Hooker’s father-in-law, died in May 1861. See also letter to Leonard Jenyns, 24 May [1862] and n. 2.
In the letter to J. D. Hooker, 25 November [1861] (Correspondence vol. 9), CD had asked Hooker whether he or Oliver knew whether ‘the male of Lychnis dioica’ had ‘rudimentary ovules in the ovarium’. Oliver either had observed or subsequently did observe such ovules (see ibid., letters to Daniel Oliver, 30 November [1861] and 7 December [1861]).
See n. 7, above.


Correspondence: The correspondence of Charles Darwin. Edited by Frederick Burkhardt et al. 29 vols to date. Cambridge: Cambridge University Press. 1985–.

‘Dimorphic condition in Primula’: On the two forms, or dimorphic condition, in the species of Primula, and on their remarkable sexual relations. By Charles Darwin. [Read 21 November 1861.] Journal of the Proceedings of the Linnean Society (Botany) 6 (1862): 77–96. [Collected papers 2: 45–63.]

Jenyns, Leonard. 1862. Memoir of the Rev. John Stevens Henslow, late rector of Hitcham, and professor of botany in the University of Cambridge. London: John Van Voorst.

Orchids: On the various contrivances by which British and foreign orchids are fertilised by insects, and on the good effects of intercrossing. By Charles Darwin. London: John Murray. 1862.

Origin: On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. By Charles Darwin. London: John Murray. 1859.

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


Has received Melastoma and Vanilla.

Has seen again the two sets of plants of Heterocentron raised from two lots of pollen from same flower – a marvellous difference in stature.

"But oh Lord what will become of my book on variation: I am involved in a multiplicity of experiments."

Observations on Viola.

CD’s fancied dimorphism of Oxalis is all a confounded mistake; only great variability in length of pistils.

Found Henslow’s life [L. Jenyns, Memoir of the Rev. J. S. Henslow (1862)] interesting but fears the public will think it dull.

Letter details

Letter no.
Charles Robert Darwin
Joseph Dalton Hooker
Sent from
Source of text
DAR 115: 152
Physical description
ALS 5pp

Please cite as

Darwin Correspondence Project, “Letter no. 3575,” accessed on 13 July 2024,

Also published in The Correspondence of Charles Darwin, vol. 10