skip to content

Darwin Correspondence Project

To Hermann Müller   5 May 1873

Down, Beckenham, Kent

May 5th 1873

My dear Sir

Owing to all sorts of interruptions and to my reading German so slowly, I have read only to p. 88 of your book; but I must have the pleasure of telling you how very valuable a work it appears to me.1 Independently of the many original observations, which of course form the most important part, the work will be one of the highest use as a means of reference to all that has been done on the subject. I am fairly astonished at the number of species of insects, the visits of which to different flowers you have recorded. You must have worked in the most indefatigable manner. About half a year ago the editor of Nature suggested that it would be a grand undertaking if a number of naturalists were to do what you have already done on so large a scale with respect to the visits of insects.2 I have been particularly glad to read your historical sketch, for I had never before seen all the references put together.3 I have sometimes feared that I was in error when I said that C. K. Sprengel did not fully perceive that cross-fertilization was the final end of the structure of flowers; but now this fear is relieved, and it is a great satisfaction to me to believe that I have aided in making his excellent book more generally known.4 Nothing has surprised me more than to see in your historical sketch how much I myself have done on the subject, as it never before occurred to me to think of all my papers as a whole. But I do not doubt that your generous appreciation of the labours of others, has led you to over estimate what I have done.

With very sincere thanks, and respect | Believe me | Yours faithfully | Charles Darwin

P.S.— I have mentioned your book to almost everyone who, as far as I know, cares for the subject in England; and I have ordered a copy to be sent to our Royal Society.5


Müller had sent CD a copy his book Die Befruchtung der Blumen durch Insekten (The fertilisation of flowers by means of insects (H. Müller 1873; see letter from Hermann Müller, 28 February 1873). CD’s annotated copy is in the Darwin Library–CUL (see Marginalia 1: 610–12).
Norman Lockyer was the editor of Nature, but CD refers to Alfred William Bennett, the biological subeditor. Bennett made his suggestion in ‘Pollen-eaters’, Nature, 16 January 1873, p. 202.
Müller reviewed the literature on the subject of the fertilisation of plants by insects in H. Müller 1873, pp. 3–27.
In Origin, p. 99, and Variation 2: 175 n. 1, CD pointed out that Sprengel had observed the contrivances employed by flowers to prevent self-fertilisation but had not appreciated that an occasional cross was advantageous or indispensable to plants. Müller also stated that Sprengel had not perceived the importance of the transport of pollen to other flowers of the same species as an essential service to the plants themselves (H. Müller 1873, p. 4). CD later quoted Müller on this point in Cross and self fertilisation, pp. 6–7.


Cross and self fertilisation: The effects of cross and self fertilisation in the vegetable kingdom. By Charles Darwin. London: John Murray. 1876.

Marginalia: Charles Darwin’s marginalia. Edited by Mario A. Di Gregorio with the assistance of Nicholas W. Gill. Vol. 1. New York and London: Garland Publishing. 1990.

Müller, Hermann. 1873. Die Befruchtung der Blumen durch Insekten und die gegenseitigen Anpassungen beider. Ein Beitrag zur Erkenntniss des ursächlichen Zusammenhanges in der organischen Natur. Leipzig: Wilhelm Engelmann.

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.


Comments on HM’s book [Die Befruchtung der Blumen (1873)]. Particularly glad to read historical sketch and discussion of work of C. K. Sprengel.

Letter details

Letter no.
Charles Robert Darwin
Heinrich Ludwig Hermann (Hermann) Müller
Sent from
Source of text
DAR 146: 434
Physical description
C 2pp

Please cite as

Darwin Correspondence Project, “Letter no. 8901,” accessed on 13 April 2024,

Also published in The Correspondence of Charles Darwin, vol. 21