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Darwin Correspondence Project

From Ernst Haeckel1   22 June 1868

Jena

22 Juni 68

Mein theurer hochverehrter Freund!

Eine ungewöhnliche Masse von dringenden Arbeiten und amtlichen Universitätsgeschäften haben mich seit 2 Monaten verhindert Ihnen zu schreiben.2 Da ich aber weiss, dass Sie von meiner unveränderlichen Anhänglichkeit und Verehrung überzeugt sind, brauche ich nicht zu fürchten, dass Sie dieses lange Schweigen missdeuten. Nehmen Sie zunächst meinen besten Dank für Ihren gütigen Brief und für die freundliche Zusendung der Nr XVI der “Fortnightly Review”, welche den Aufsatz von Lewes über Ihre Theorie enthält. Er hat mich sehr interessirt. Ich kann mir denken, wie Mr. Lewes, der so viel allgemeines Interesse besitzt, und dem wir Deutschen die beste Biographie Göthes verdanken, sich für Ihre Entwickelungs-Theorie interessirt. Was er über die Eintheilung der ⁠⟨⁠Menschen⁠⟩⁠ in geborene Monisten und Duali⁠⟨⁠sten⁠⟩⁠ sagt, ist sehr gut, obwohl es in beiden Richtungen auch viel “angepasste” Charak⁠⟨⁠tere gibt⁠⟩⁠.3

Die Beobachtungen über Bastarde vom Lepus timidus und L. cuniculus habe ich an neuen Exemplaren, welche mir Dr. Conrad von seinem Gute sandte, fortgesetzt. Sie sind sehr interessant. In meiner demnächst erscheinenden “Schöpfungsgeschichte” werden sie beschrieben werden.4 Dr. Conrad liess im Juni 1866 acht junge wilde Hasen einfangen und sperrte sie mit jungen Caninchen von der gewöhnlichen kleinen Hausrasse zusammen (grau mit weissem Ringel um den Hals). Nur ein Paar blieb am Leben, ein männlicher Hase und ein weibliches Caninchen, beide sorgfältig zusammen isolirt. Letzteres warf im Januar 1867 drei Junge von grauer Farbe, später wiederholt mehrere.

Lepus Lepus
timidus cuniculus
mas femin.
\ /
Lepus Darwini
I Gen mas et femin.
grau
\ /
⁠⟨⁠II⁠⟩⁠ Gen. theil grau,
⁠⟨⁠th⁠⟩⁠eils schwarz

Diese Bastarde pflanzten sich untereinander, ohne Kreuzung mit einem der Eltern, mehrfach fort (II Gener.) Die ersten Bastarde der II Generation wurden schon im Juli 1867 geboren. Ich besitze drei Individuen von späteren Bastarden der II Generation. Davon sind 2 grau wie die Eltern. Eins aber ist in die schwarze Farbe eines früheren Kaninchen-Vorfahren zurückgeschlagen. Im Ganzen gleichen die Bastarde der II. Gen. mehr den Kaninchen, besonders im Bezug auf die kürzeren Beine. Dagegen haben sie die längeren Ohren der Hasen. Ich nenne diese Bastarde vom männl. Hasen und weibl. Caninchen, die sich in reiner Inzucht fortpflanzen, Lepus Darwinii. Dr. Conrad wird die Versuche auf seinem Gute fortsetzen.

Beifolgend erhalten Sie eine Beschreibung der Moneren, die ich auf den canarischen Inseln beobachtete, und ein Paar populäre Vorträge über Entstehung des Menschen.5 Ferner lege ich eine Tafel mit Embryonen von Menschen und anderen Wirbelthieren bei, welche in meine “Schöpfungs geschichte” kommt. Letztere (Vorträge, die ich hier im vorigen Winter hielt) werden in 2 Monaten etwa erscheinen. Ich bin jetzt wieder mit Stammbäumen beschäftigt, welche diese “natürliche Schöpfungsgeschichte” begleiten sollen.6 Ausserdem untersuche ich die Medusen von den canarischen Inseln, unter denen manche interessante sind.7 Wenn man nur drei mal so viel Zeit hätte, und wenn der Tag statt 24 lieber 72 Stunden hätte! Die Zeit ist immer viel zu kurz für alle Aufgaben, die vor uns liegen!

Die Agitation für und wider Darwin ist jetzt in Deutschland sehr lebhaft. Fast jede Woche erscheinen darüber ein paar Broschüren, das meiste allerdings so schlecht, dass man es nicht zu lesen braucht!

Mir und meiner Frau8 geht es sehr gut. Ich hoffe, dass dasselbe mit Ihnen, theurer Freund, der Fall ist, und dass Sie mit Ihrer Gesundheit ganz zufrieden sind.

Mit der Bitte, mich Mrs. und Miss Darwin9 bestens zu empfehlen in unveränderlicher Treue und Verehrung Ihr Ganz ergebener | Haeckel

Footnotes

For a translation of this letter, see Correspondence vol. 16, Appendix I.
Haeckel’s last extant letter to CD is that of 23 March 1868.
George Henry Lewes published a series of articles titled ‘Mr. Darwin’s hypotheses’ between 1 April and 1 November 1868 (Lewes 1868b). The reference here is to the first of them, in Fortnightly Review 3: 353–73. Haeckel also refers to Lewes’s The life and work of Goethe (Johann Wolfgang von Goethe; Lewes 1855), which was translated into German in 1857 (Lewes 1857). Lewes proposed an innate disposition towards either monistic or dualistic conceptions of reality in Lewes 1868b, pp. 354–5. On Haeckel’s monism, see Di Gregorio 2005, pp. 338–42.
See letter from Ernst Haeckel, 23 March 1868. Haeckel refers to Johannes Ernst Conrad; he mentioned Conrad’s experiments in his Natürliche Schöpfungsgeschichte, p. 222 (Haeckel 1868c; see also Haeckel 1876, 1: 147). CD mentioned claims that hare–rabbit hybrids had been produced in captivity in Variation 1: 105, 2: 152 n. 20, but also stated that the existence of a hybrid breed that could propagate itself had been positively denied. He did not alter his statements in the second edition of Variation (Variation 2d ed., 1: 109, 2: 135 n. 20). Lepus timidus is the mountain hare; L. cuniculus (now Oryctolagus cuniculus subsp. cuniculus) is the European rabbit.
Haeckel refers to his ‘Monographie der Moneren’ (Haeckel 1868a) and to his ‘Ueber die Entstehung und den Stammbaum des Menschengeschlechts’ (Haeckel 1868b). There are copies in the Darwin Pamphlet Collection–CUL; the pages of Haeckel 1868a are uncut, but Haeckel 1868b is annotated.
The illustration of embryos that was later published in Haeckel 1868c is at DAR 80: B123 (Haeckel 1868c, plate on pp. 240b and 240c; see also Haeckel 1876, 1: plate between pp. 306 and 307). The illustration appeared in chapter 12 of Haeckel 1868c, which CD annotated ‘read’ on the table of contents of his copy, now in the Darwin Library–CUL (see Marginalia 1: 358–60). Haeckel 1868c included a number of genealogical trees printed at the end of the volume.
Haeckel had visited the Canary Islands in late 1866 and 1867 (see Correspondence vol. 15).

Bibliography

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

Di Gregorio, Mario A. 2005. From here to eternity: Ernst Haeckel and scientific faith. Göttingen: Vandenhoeck & Ruprecht.

Lewes, George Henry. 1855. The life and works of Goethe: with sketches of his age and contemporaries, from published and unpublished sources. 2 vols. London: David Nutt.

Lewes, George Henry. 1857. Goethe’s Leben und Schriften. Translated by Julius Frese. 2 vols. Berlin: F. Duncker.

Lewes, George Henry. 1868b. Mr. Darwin’s hypotheses. Fortnightly Review n.s. 3: 353–73, 611–28; 4: 61–80, 492–509.

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.

Variation 2d ed.: The variation of animals and plants under domestication. By Charles Darwin. 2d edition. 2 vols. London: John Murray. 1875.

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

Translation

From Ernst Haeckel1   22 June 1868

Jena

22 June 1868

My dear, most esteemed friend!

An unusual amount of urgent work and official university matters have kept me from writing to you for two months.2 Since I know that you are convinced of my unchangeable devotion and veneration, I need not fear that you will misinterpret this long silence. First of all, please accept my thanks for your kind letter and courtesy in forwarding Nr. XVI of the “Fortnightly Review”, which contains Lewes’ essay on your theory. It was very interesting. I can imagine how Mr. Lewes, who has so many general interests and whom we Germans have to thank for the best biography of Goethe, is interested in your theory of development. What he has to say about the division of human beings into born monists and dualists is very good, although there ⁠⟨⁠are⁠⟩⁠ also many “adapted” characters in both directions.3

I have continued observations on the hybrids of Lepus timidus and L. cuniculus with new specimens that Dr. Conrad kindly sent me from his estate. They are very interesting. I will describe them in my “History of Creation”, which is due to come out shortly.4 In June 1866 Dr. Conrad had eight young wild hares caught and he locked them up with young rabbits of the common small domestic race (grey with a white ring around the neck). Only one pair stayed alive, a male hare and a female rabbit, both carefully isolated together. The latter produced three offspring of a grey colour in January 1867 and later produced several more.

Lepus Lepus
timidus cuniculus
male female
\ /
Lepus Darwini
I Gen male et female.
grey
\ /
⁠⟨⁠II⁠⟩⁠ Gen. partly grey,
partly black

These hybrids multiplied amongst themselves many times, without crossing with one of the parents (II gener.) The first hybrids of the II generation were already born in July 1867. I have three individuals of the later hybrids of the II generation. Two of these are grey like the parents. But one has reverted to the black colour of an earlier rabbit ancestor. On the whole the hybrids of the II generation resemble rabbits more, especially with regard to the shorter legs. On the other hand, they have the longer ears of the hare. I call these hybrids from the male hare and female rabbit that have been multiplying in pure inbreeding: Lepus Darwinii. Dr. Conrad will continue the experiments on his estate.

Enclosed you will find a description of the Monera which I observed on the Canary Islands and a couple of popular lectures on the origin of humans.5 I also attach an illustration of embryos of humans and other vertebrates, which is from my “History of Creation”. The latter (lectures that I gave here last winter) will appear in about 2 months. I am now busy again with family trees that should accompany this “natural history of creation”.6 Apart from that I am examining the Medusae from the Canary Islands, many of which are interesting.7 If only one had three times as much time and if the day had 72 and not 24 hours! Time is always much too short for all the tasks before us!

The agitation for and against Darwin is now very lively in Germany. Almost every week a couple of pamphlets appear, the majority of course so bad that it’s not necessary to read them!

My wife8 and I are very well. I hope that the same is the case with you, dear friend, and that you are content with your health.

With my best regards to Mrs. and Miss Darwin,9 I remain in unchanging faith and veneration your most humble | Haeckel

Footnotes

For a transcription of this letter in its original German, see part I: 597–8.
Haeckel’s last extant letter to CD is that of 23 March 1868.
George Henry Lewes published a series of articles titled ‘Mr. Darwin’s hypotheses’ between 1 April and 1 November 1868 (Lewes 1868b). The reference here is to the first of them, in Fortnightly Review 3: 353–73. Haeckel also refers to Lewes’s The life and work of Goethe (Johann Wolfgang von Goethe; Lewes 1855), which was translated into German in 1857 (Lewes 1857). Lewes proposed an innate disposition towards either monistic or dualistic conceptions of reality in Lewes 1868b, pp. 354–5. On Haeckel’s monism, see Di Gregorio 2005, pp. 338–42.
See letter from Ernst Haeckel, 23 March 1868. Haeckel refers to Johannes Ernst Conrad; he mentioned Conrad’s experiments in his Natürliche Schöpfungsgeschichte, p. 222 (Haeckel 1868c; see also Haeckel 1876, 1: 147). CD mentioned claims that hare–rabbit hybrids had been produced in captivity in Variation 1: 105, 2: 152 n. 20, but also stated that the existence of a hybrid breed that could propagate itself had been positively denied. He did not alter his statements in the second edition of Variation (Variation 2d ed., 1: 109, 2: 135 n. 20). Lepus timidus is the mountain hare; L. cuniculus (now Oryctolagus cuniculus subsp. cuniculus) is the European rabbit.
Haeckel refers to his ‘Monographie der Moneren’ (Haeckel 1868a) and to his ‘Ueber die Entstehung und den Stammbaum des Menschengeschlechts’ (Haeckel 1868b). There are copies in the Darwin Pamphlet Collection–CUL; the pages of Haeckel 1868a are uncut, but Haeckel 1868b is annotated.
The illustration of embryos that was later published in Haeckel 1868c is at DAR 80: B123 (Haeckel 1868c, plate on pp. 240b and 240c; see also Haeckel 1876, 1: plate between pp. 306 and 307). The illustration appeared in chapter 12 of Haeckel 1868c, which CD annotated ‘read’ on the table of contents of his copy, now in the Darwin Library–CUL (see Marginalia 1: 358–60). Haeckel 1868c included a number of genealogical trees printed at the end of the volume.
Haeckel had visited the Canary Islands in late 1866 and 1867 (see Correspondence vol. 15).

Bibliography

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

Di Gregorio, Mario A. 2005. From here to eternity: Ernst Haeckel and scientific faith. Göttingen: Vandenhoeck & Ruprecht.

Lewes, George Henry. 1855. The life and works of Goethe: with sketches of his age and contemporaries, from published and unpublished sources. 2 vols. London: David Nutt.

Lewes, George Henry. 1857. Goethe’s Leben und Schriften. Translated by Julius Frese. 2 vols. Berlin: F. Duncker.

Lewes, George Henry. 1868b. Mr. Darwin’s hypotheses. Fortnightly Review n.s. 3: 353–73, 611–28; 4: 61–80, 492–509.

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.

Variation 2d ed.: The variation of animals and plants under domestication. By Charles Darwin. 2d edition. 2 vols. London: John Murray. 1875.

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

Summary

Thanks CD for article by G. H. Lewes ["Mr Darwin’s hypotheses, pt 1", Fortn. Rev. n.s. 3 (1868): 353–73]. Comments on article.

Describes hybridisation experiment carried out on rabbits and hares by Dr Conrad.

Encloses description of Monera

and a phylogenetic table of vertebrates.

Mentions work on Medusae.

The controversy over CD in Germany.

Letter details

Letter no.
DCP-LETT-6255
From
Ernst Philipp August (Ernst) Haeckel
To
Charles Robert Darwin
Sent from
Jena
Source of text
DAR 166: 48
Physical description
ALS 4pp (German) damaged

Please cite as

Darwin Correspondence Project, “Letter no. 6255,” accessed on 28 March 2024, https://www.darwinproject.ac.uk/letter/?docId=letters/DCP-LETT-6255.xml

Also published in The Correspondence of Charles Darwin, vol. 16

letter