skip to content

Darwin Correspondence Project

To Daniel Oliver   4 April [1861]1

Down Bromley Kent

Ap. 4th

My dear Sir

Very many thanks for the Primulas (& about common Primrose) which I received this morning & examined.2 Only one was dimorphic: but I have every reason to suppose the others would have been so, had you possessed a greater number of plants.— P. Siberica, however, seems to differ from all other species in not being dimorphic.—3

I have been deeply grieved to hear about Prof.— Henslow—

Yours very sincerely | C. Darwin

As P. Siberica is apparently so exceptional, would you ask Mr Croker, if you have other plants, which come into flower to send me 2 or 3 flowers (not whole trusses) for examination, in order that I may see whether they present any incipient trace of dimorphism.—

But if your plants have been increased all by offsets from same original plant, it will be no use to send them. As the character is permanent by offsets.

I do not know whether I shall succeed in making out the meaning of the dimorphism; but I have not been idle, for I have made much above 100 crosses with the pollen of the different sizes.

The lot sent has been most interesting to me.— Pray thank Mr Croker—4

Do not trouble yourself to write if you can at any time send me other specimens of P. Siberica—


Dated by the relationship to the letters to Daniel Oliver, 23 March [1861] and 1 April [1861] and by the reference to John Stevens Henslow’s illness.
CD had asked Oliver to send him specimens of various species of Primula (see letter to Daniel Oliver, 23 March [1861]).
In his paper ‘On the two forms, or dimorphic condition, in the species of Primula, and on their remarkable sexual relations’ (Journal of the Proceedings of the Linnean Society (Botany) 6 (1862): 77–96), CD mentioned that ‘unless indeed this single specimen was anomalous’, P. sibirica was not dimorphic (ibid., p. 81; Collected papers 2: 48–9).
Charles William Crocker was foreman of the propagating department at the Royal Botanic Gardens, Kew.


Primula siberica seems to be the only non-dimorphic species. Has made over one hundred Primula crosses.

Regrets Henslow’s illness.

Letter details

Letter no.
Charles Robert Darwin
Daniel Oliver
Sent from
Source of text
Down House (MS 10: 29)
Physical description

Please cite as

Darwin Correspondence Project, “Letter no. 3110,” accessed on 28 June 2017,

Also published in The Correspondence of Charles Darwin, vol. 9