skip to content

Darwin Correspondence Project

To C. G. Semper   6 February 1881

Down, | Beckenham, Kent. | (Railway Station | Orpington. S.E.R.)

Feb. 6th 1881

Dear Professor Semper

Owing to all sorts of work I have only just now finished reading your “Nat. Conditions of existence”.1 Although a book of small size it contains an astonishing amount of matter; & I have been particularly struck with the originality with which you treat so many subjects, & at your scrupulous accuracy. In far the greater number of points I quite follow you in your conclusions; but I differ on some, & I suppose that no two men in the world would fully agree on so many difficult subjects. I have been interested on so many points, I can hardly say on which most. Perhaps as much on Geograph. Distribution as on any other, especially in relation to M. Wagner.2 (No, no! about parasites interested me even more).3 How strange that Wagner shd. have thought that I meant by struggle for existence, struggle for food. It is curious that he shd. not have thought of the endless adaptations for the dispersal of seeds & the fertilisation of flowers.—

Again I was much interested about Branchipus & Artemisia: when I read imperfectly some years ago the original paper, I could not avoid thinking that some special explanation would hereafter be found for so curious a case:4 I speculated whether a species very liable to repeated & great changes of conditions, might not acquire a fluctuating condition, ready to be adapted to either conditions.— With respect to Arctic animals, being white, (p. 116 of your book) it might perhaps be worth your looking at what I say from Pallas & my own observations in the Descent of Man (later Editions) Ch. 8 p 229 & Ch 18 p. 542.—5

I quite agree with what I gather to be your judgment, viz that the direct action of the conditions of life on organisms, or the cause of their variability is the most important of all subjects for the future..6 For some few years I have been thinking of commencing a set of experiments on Plants, for they almost invariably vary when cultivated. I fancy that I see my way with the aid of continued self-fertilisation. But I am too old & have not strength enough. Nevertheless the hope occasionally revives.

Finally, let me thank you for the very kind manner in which you often refer to my works, & for the even still kinder manner in which you disagree with me.—

With cordial thanks for the pleasure & instruction which I have derived from your book, I remain | My dear Professor Semper | Yours sincerely | Charles Darwin

My son Francis begs to be very kindly remembered to you.—7

Footnotes

CD’s lightly annotated copy of Semper’s book The natural conditions of existence as they affect animal life (Semper 1881) is in the Darwin Library–CUL. He had asked for a copy to be sent to him as soon as it was published (see Correspondence vol. 28, letter to Williams & Norgate, [before 4 September 1880] and n. 3).
Moritz Wagner had argued in opposition to CD that natural selection could operate only in conjunction with migration; Semper suggested that the two theories were not as opposed as Wagner thought (see Semper 1881, pp. 288–93).
Semper 1881, pp. 331–52.
In Semper 1881, p. 158, Semper described Wladimir Schmankewitsch’s experiments showing that when water salinity was slowly reduced, Artemia (the genus of brine shrimp; misspelled as ‘Artemisia’ by CD) produced offspring that over generations resembled Branchipus (the genus of freshwater shrimp-like branchiopod crustaceans). Schmankewitsch’s article on the subject was published in 1877 (Schmankewitsch 1877); CD’s annotated copy is in the Darwin Pamphlet Collection–CUL. CD wrote on the cover of his offprint: ‘On changes in Crustaceans from salt water’, adding, with double underlining, ‘Very good’. From the 1890s, however, Schmankewitsch’s views were heavily criticised (Vucinich 1988, pp. 84–5, 158–9, 371). Outside Germany his name was usually given as Vladimir Ivanovich Shmankevich.
In Descent 2d ed., pp. 229 and 542, CD reported that Siberian domestic cattle and horses as well as wolves, some antelopes, elk, and reindeer become lighter coloured during the winter, citing Pyotr Simon Pallas in Pallas 1778.
In the preface of his book, Semper had stated, ‘It appears to me that of all the properties of the animal organism, Variability is that which may first and most easily be traced by exact investigation to its efficient causes; and, as it is beyond a doubt the subject around which at the present moment the strife of opinions is most violent, it is that which will be most likely to repay the trouble of closer research’ (Semper 1881, p. vi).
Francis Darwin had worked in Julius Sachs’s laboratory in Würzburg in the summer of 1878, and first met Semper during this visit (see Correspondence vol. 26, letter from Francis Darwin, [21 July 1878]).

Bibliography

Descent 2d ed.: The descent of man, and selection in relation to sex. By Charles Darwin. 2d edition. London: John Murray. 1874.

Pallas, Pyotr Simon. 1778. Novae species quadrupedum e glirium ordine: cum illustrationibus variis complurium ex hoc ordine animalium. Erlangen: Wolfgang Walther.

Schmankewitsch, Wladimir. 1877. Zur Kenntniss des Einflusses der äusseren Lebensbedingungen auf die Organisation der Thiere. Zeitschrift für wissenschaftliche Zoologie 29: 429–94.

Semper, Karl. 1881. The natural conditions of existence as they affect animal life. London: C. Kegan Paul & Co.

Vucinich, Alexander. 1988. Darwin in Russian thought. Berkeley: University of California Press.

Summary

Comments on CGS’s The natural conditions of existence [1881] and on views of Moritz Wagner on geographical distribution.

Discusses cause of variability.

Letter details

Letter no.
DCP-LETT-13040
From
Charles Robert Darwin
To
Carl Gottfried Semper
Sent from
Down
Source of text
Universitäts- und Landesbibliothek Düsseldorf (slg 60/Dok/62)
Physical description
ALS 6pp

Please cite as

Darwin Correspondence Project, “Letter no. 13040,” accessed on 28 March 2024, https://www.darwinproject.ac.uk/letter/?docId=letters/DCP-LETT-13040.xml

letter