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Darwin Correspondence Project

From Fritz Müller1   6 March 1866

Desterro, Brazil,

6. März 1866.

Verehrter Herr!

Da ich einen Brief vor ein paar Wochen abgeschickt habe, so schreibe ich Ihnen heute nur, um Ihnen zu sagen, dass ich Ihren freundlichen Brief vom 11. Januar richtig empfing, und um Ihnen für das neue werthvolle Geschenk zu danken, das Sie mir anzubieten die Güte haben.2 Da alles, was von Ihnen kommt, mir immer sehr angenehm sein wird, und da alles, was sich auf Ihre Theorie bezieht, meiner grössten Theilnahme immer sicher ist, so werde ich auch mit grosser Befriedigung und herzlichem Dank die zweite Auflage der deutschen Uebersetzung der “Origin” in Empfang nehmen.

Die letzten zwei Sommer (von 1863 auf 64 sowohl als von 64 auf 65) waren hier ungewöhnlich trocken und diese Trockenheit scheint, obwohl sie nicht stark genug war, dem Ackerbau viel Schaden zu thun, dennoch manche Veränderungen in der relativen Häufigkeit vieler unserer Thiere und Pflanzen hervorgebracht zu haben;3 verschiedene Arten sind augenscheinlich aus Oertlichkeiten verschwunden, wo sie früher in Menge vorkamen.— So waren die Ränder einiger Gräben nahe bei der “Villa do Itajahy”4 früher bedeckt von einer sehr zierlichen Aeschynomene, von der ich, als ich letzthin dort vorbeikam, nicht ein einziges Exemplar fand; die Stelle dieser Art war besetzt von einer anderen noch schöneren Leguminose, nemlich Daubentonia.5 Diese letztere sah ich nie vor der grossen Ueberschwemmung vor dem Jahre 1855; seitdem ist sie an den Ufern des Itajahy sehr häufig geworden.—6 In einem kleinen Graben nahe der Küste lebten früher Myriaden eines zarten Closterium;7 dieser Graben trocknete vollständig aus und blieb so, bis der gegenwärtige regnerische Sommer ihn wieder mit Wasser füllte; nun sind die Conferve, die Cypris, die Cyclops u.s.w. wieder erschienen,8 aber vergeblich sah ich mich um nach dem Closterium, von dem Max Schultze einige Zeichnungen für sein Archiv zu haben wünschte.—9 Vor ein paar Tagen wollte ich einem Freunde die Bewegung in den Wurzelhaaren einer Hydrocharidee (Limnobium) zeigen;10 ich ging deswegen nach einem Graben, den ich in früheren Jahren jeden Tag überschreiten musste und der damals ausschliesslich von dieser Pflanze bedeckt war; jetzt konnte ich kaum ein paar Exemplare sammeln, da die Pflanze vollständig durch eine ausserordentlich häufige Heteranthera ersetzt war.—11 Unsere einzige Orchidee aus der Ophrys-Gruppe (Bonatea) scheint auch der Dürre auf unserer Insel unterlegen zu sein, sie kommt nur noch auf dem Festlande vor.—12 Orchestia Darwinii war in Folge der Dürre ausserordentlich selten geworden; jetzt ist der grössere Theil des Gebietes, welches sie früher mit Ausschluss jeder andern Art von Amphipoden einnahm, in Beschlag genommen von Orch. Tucuranna, und obwohl sie auf dem kleinen Gebiet, welches sie noch inne hat, sehr zahlreich vorkommt, so gelang es mir doch nicht, ein einziges Exemplar einer der beiden Formen von Männchen zu finden, welche früher beide offenbar gleich häufig waren.—13 Ohne Zweifel wird es noch eine grosse Anzahl anderer Pflanzen und Thiere geben, welche durch jene Dürre beeinflusst sind; auf alle, die ich erwähnte, zu achten, wurde ich durch verschiedene anderweite Beweggründe veranlasst und stellte so zufällig die Veränderung fest.

Auch zu Zeiten, wo kein aussergewöhnlicher Wechsel in den physikalischen Bedingungen das Ergebniss des “Kampfes ums Dasein” beeinflusst, sind die relativen Zahlen der verschiedenen thierischen und pflanzlichen Bewohner eines Landes oder Meeres keineswegs unveränderlich, sondern, wie ich meine, erheblich wechselnde Grössen, und dies wahrscheinlich noch vielmehr dort, wo Urvegetation das ganze Land bedeckt, als wo menschliche Kultur den wilden Thieren und Pflanzen kaum ein Mindestmass von Fläche übrig gelassen hat, auf dem sie um ihr Dasein kämpfen. Ich entsinne mich, dass auf dem schmalen Küstenstreifen dicht bei meinem Hause vielfacher Wechsel in der Fauna innerhalb der letzten 10 Jahre stattgefunden hat;14 unglücklicherweise sah ich in früheren Jahren solche Veränderungen nicht voraus, auch glaubte ich nicht, dass sie von irgend welcher wissenschaftlicher Wichtigkeit wären; ich bin daher jetzt nicht im Stande, genauen Bericht von ihnen zu geben. Einer der Fälle, die mich am meisten in Erstaunen setzten, ist der folgende: Ein kleiner Felsen nahe bei der Küste, nur ein paar Fuss breit, war während der ersten Jahre meines hiesigen Aufenthaltes mit grossen Büschen eines braunen Bryozoon bedeckt; vor ungefähr 6 oder 7 Jahren sah ich zum ersten Male an einem benachbarten Felsen einige Exemplare eines anderen sehr zierlichen weissen Bryozoon, welches einige Jahre hindurch recht selten blieb; ungefähr 4 oder 5 Jahre danach wurde dieses aber plötzlich sehr häufig und bedeckte alle Felsen in der Nachbarschaft; auf unserm kleinen Felsen war jeder Ast des braunen Bryozoon mit Büschchen des weissen besetzt, und alle Exemplare des ersteren starben ab. Aber die Herrschaft der weissen Art war von kurzer Dauer; ungefähr ein halbes Jahr nach ihrer grössten Verbreitung begannen sie abzusterben und immer seltener zu werden; gegenwärtig kenne ich keinen Felsen mehr, von dem man sie beschaffen könnte. Was mir nun aber das Merkwürdigste erschien, ist, dass die braune Bryozoe, nachdem der weisse Eindringling verschwunden war, ihre Herrschaft auf dem Felsen nicht wieder aufgenommen hat, obwohl sie ihn doch früher viele Jahre fast ausschliesslich bedeckt hatte; aber da ist jetzt eine vollständig neue Fauna, in der unter den befestigten Arten eine Clavellina15 vorherrscht.

Footnotes

For a translation of this letter, see Correspondence vol.14, Appendix I. For an account of the reconstruction of Fritz Müller’s letters to CD, see the letter from Fritz Müller, 13 February 1866, n. 1.
Müller refers to his letter to CD of 13 February 1866; in his letter to Fritz Müller of 11 January 1866, CD offered to send him a copy of the second German edition of Origin (Bronn trans. 1863).
For an account of deforestation, agricultural intensification, and climatic instability in coastal south-eastern Brazil during the nineteenth century, see Dean 1995, pp. 191–6 et seq.
Müller refers to the town of Itajahy (now Itajaí) at the mouth of the Itajaí Açu river on the Brazilian mainland.
Aeschynomeme and Daubentonia (now Sesbania) are both large genera of leguminous plants (Mabberley 1997).
Müller refers to the Itajaí Açu river. Müller’s homestead was beside the river about twenty-five miles inland from the the town of Itajahy, and was later incorporated within the town of Blumenau. In November 1855, flooding had caused the river to rise nearly ten metres above its normal level (Möller 1915–21, 3: 63–4).
Closterium is a genus of freshwater green algae.
Müller refers to filamentous freshwater algae; to Cypris, a genus of ostracods or minute freshwater crustaceans; and to Cyclops, a genus of copepods that are also minute freshwater crustaceans. Müller referred to Cypris, Cyclops, and other copepods in several parts of Für Darwin (F. Müller 1864c; translated as Dallas trans. 1869).
Max Johann Sigismund Schultze founded Archiv für mikroskopische Anatomie in 1865; the journal did not publish illustrations of Closterium during its first ten years, the period of Schultze’s editorship (Möller 1915–21, 2: IV et seq.). Schultze corresponded with Müller and in 1857 gave him a microscope to assist his biological work (ibid., 1: 75).
Limnobium is a genus of the family Hydrocharitaceae; protoplasmic streaming, that is, the movement of the contents of the protoplasm within individual cells, may be observed in the root hairs of the floating herb L. spongia (Mabberley 1997).
Heteranthera is a genus of aquatic plants in the family Pontederiaceae.
The flora of Santa Catarina state, where Müller lived, includes one species of the orchid genus Bonatea, B. pratensis, now Habenaria pratensis.
Müller refers to the small crustaceans Orchestia darwinii and O. tucurauna (see F. Müller 1864c, p. 54, and Dallas trans. 1869, pp. 79–80).
Müller refers to the coast of the island of Santa Catarina, Brazil. As well as his homestead beside the Itajaí Açu river in the mainland part of Santa Catarina state, Müller had a house at Destêrro on the island of Santa Catarina (DSB).
Müller refers to Clavelina, a genus of sea squirts in the class Ascidiacea.

Bibliography

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

Dean, Warren. 1995. With broadax and firebrand: the destruction of the Brazilian Atlantic forest. Berkeley, Calif., and London: University of California Press.

DSB: Dictionary of scientific biography. Edited by Charles Coulston Gillispie and Frederic L. Holmes. 18 vols. including index and supplements. New York: Charles Scribner’s Sons. 1970–90.

Mabberley, David J. 1997. The plant-book. A portable dictionary of the vascular plants. 2d edition. Cambridge: Cambridge University Press.

Möller, Alfred, ed. 1915–21. Fritz Müller. Werke, Briefe und Leben. 3 vols in 5. Jena: Gustav Fischer.

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.

Translation

From Fritz Müller1   6 March 1866

Desterro, Brazil,

6 March 1866.

Dear Sir,

Since I sent off a letter only a few weeks ago I am writing today only to tell you that I have received your kind letter of 11 January in good order and to thank you for the valuable present which you kindly offered.2 Since everything coming from you is always very welcome and since everything regarding your theory is always certain to command my greatest interest, I shall receive the second edition of the German translation of “Origin” with great satisfaction and cordial thanks.

Here the last two summers (1863–64 and also 64–65) have been unusually dry, and this drought, while not severe enough to cause much damage to agriculture, has nevertheless brought about a number of changes in the relative frequency of many of our animals and plants.3 Various species seem to have disappeared from places where they used to occur in profusion.— For instance, the edges of a number of ditches near “Villa do Itajahy”4 used to be covered by a very dainty Aeschynomene, but when I last passed by I did not find one single specimen; now there is an even more beautiful leguminous plant in its place, a Daubentonia.5 I never saw this plant prior to the great inundation of 1855, but since then it has become very common on the banks of the Itajahy.—6 In a little ditch near the coast there used to be myriads of delicate Closterium;7 this ditch dried out completely and remained so until the current rainy summer refilled it with water. Now the Confervæ, the Cypris, the Cyclops, etc. have reappeared,8 but I looked in vain for the Closterium of which Max Schultze wanted drawings for his Archive.—9 A couple of days ago I wanted to show a friend the movement in the root hairs of one of the Hydrocharideæ (Limnobium).10 For this purpose I went to a ditch that I had to cross daily in previous years and that was then covered almost exclusively by this plant. Now I was barely able to collect a couple of specimens, as the plant had been completely replaced by an extremely common Heteranthera.—11 Our only orchid from the Ophrys group (Bonatea) also seems to have succumbed to the drought on our island: it now occurs only on the mainland.—12 Orchestia Darwinii had become exceedingly rare following the drought; now the larger part of the area it used to occupy to the exclusion of every other species of Amphipoda has been seized by Orch. Tucuranna, and while it occurs in great profusion in the small area that it still holds, I did not succeed in finding one single specimen of either male form, both of which used to be equally common, it seemed.—13 No doubt there will be a great number of other plants and animals that have been influenced by this drought. I was prompted to pay attention to the ones I mentioned for various unrelated reasons and so I noticed the changes by chance.

Even at times when no extraordinary changes in the physical conditions influence the outcome of the “struggle for survival”, the relative numbers of various animal and plant inhabitants of a land or an ocean by no means remain unchanged. Rather, in my opinion the numbers fluctuate considerably, and probably much more so where the primeval vegetation covers the whole land than where human culture has left wild animals and plants barely a minimum of surface area on which to struggle for survival. I recall that in the last 10 years many changes have occurred in the fauna of the narrow coastal strip close to my house.14 In earlier years, I did not anticipate such changes, alas, and it did not occur to me that they might be of any scientific importance. Thus I am not in a position to provide you with a precise report. One of the cases that surprised me the most is the following: there is a small rock near the coast, only a few feet across, that was covered with large bushes of a brown bryozoan during the first years of my stay here. Some 6 or 7 years ago I noticed for the first time some specimens of another very gracious white bryozoan on a neighbouring rock. It remained quite rare for a few years, but some 4 or 5 years later it suddenly became very common and covered all the rocks in the neighbourhood; on our small rock every branch of the brown bryozoan was covered with small bushes of the white one and all specimens of the former died. But the reign of the white species was brief; approximately half a year after its greatest diffusion it began to die off and become rarer and rarer. At the moment I no longer know of any rock on which you could get it. The strangest thing about it seems to me to be that the brown bryozoan did not recover its dominant position on the rock after the intruder had disappeared, despite the fact that for many years it had covered it almost exclusively. But now there is a completely new fauna and amongst the attached species a Clavellina15 is predominant.

Footnotes

For a transcription of this letter in the German of its published source, see pp. 93–5. According to Alfred Möller, all Fritz Müller’s letters to CD were written in English (see Möller ed. 1915–21, 2: 72 n.); most of them have not been found. Many of the letters were later sent by Francis Darwin to Möller, who translated them into German for his Fritz Müller: Werke, Briefe und Leben (Möller ed. 1915–21). Möller also found final drafts of some Müller letters among the Fritz Müller papers and included these in their original English form (ibid., 2: 72 n). Where the original English versions are missing, the published version, usually appearing in German translation, has been used.
Müller refers to his letter to CD of 13 February 1866; in his letter to Fritz Müller of 11 January 1866, CD offered to send him a copy of the second German edition of Origin (Bronn trans. 1863).
For an account of deforestation, agricultural intensification, and climatic instability in coastal south-eastern Brazil during the nineteenth century, see Dean 1995, pp. 191–6 et seq.
Müller refers to the town of Itajahy (now Itajaí) at the mouth of the Itajaí Açu river on the Brazilian mainland.
Aeschynomeme and Daubentonia (now Sesbania) are both large genera of leguminous plants (Mabberley 1997).
Müller refers to the Itajaí Açu river. Müller’s homestead was beside the river about twenty-five miles inland from the the town of Itajahy, and was later incorporated within the town of Blumenau. In November 1855, flooding had caused the river to rise nearly ten metres above its normal level (Möller 1915–21, 3: 63–4).
Closterium is a genus of freshwater green algae.
Müller refers to filamentous freshwater algae; to Cypris, a genus of ostracods or minute freshwater crustaceans; and to Cyclops, a genus of copepods that are also minute freshwater crustaceans. Müller referred to Cypris, Cyclops, and other copepods in several parts of Für Darwin (F. Müller 1864c; translated as Dallas trans. 1869).
Max Johann Sigismund Schultze founded Archiv für mikroskopische Anatomie in 1865; the journal did not publish illustrations of Closterium during its first ten years, the period of Schultze’s editorship (Möller 1915–21, 2: IV et seq.). Schultze corresponded with Müller and in 1857 gave him a microscope to assist his biological work (ibid., 1: 75).
Limnobium is a genus of the family Hydrocharitaceae; protoplasmic streaming, that is, the movement of the contents of the protoplasm within individual cells, may be observed in the root hairs of the floating herb L. spongia (Mabberley 1997).
Heteranthera is a genus of aquatic plants in the family Pontederiaceae.
The flora of Santa Catarina state, where Müller lived, includes one species of the orchid genus Bonatea, B. pratensis, now Habenaria pratensis.
Müller refers to the small crustaceans Orchestia darwinii and O. tucurauna (see F. Müller 1864c, p. 54, and Dallas trans. 1869, pp. 79–80).
Müller refers to the coast of the island of Santa Catarina, Brazil. As well as his homestead beside the Itajaí Açu river in the mainland part of Santa Catarina state, Müller had a house at Destêrro on the island of Santa Catarina (DSB).
Müller refers to Clavelina, a genus of sea squirts in the class Ascidiacea.

Bibliography

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

Dean, Warren. 1995. With broadax and firebrand: the destruction of the Brazilian Atlantic forest. Berkeley, Calif., and London: University of California Press.

DSB: Dictionary of scientific biography. Edited by Charles Coulston Gillispie and Frederic L. Holmes. 18 vols. including index and supplements. New York: Charles Scribner’s Sons. 1970–90.

Mabberley, David J. 1997. The plant-book. A portable dictionary of the vascular plants. 2d edition. Cambridge: Cambridge University Press.

Möller, Alfred, ed. 1915–21. Fritz Müller. Werke, Briefe und Leben. 3 vols in 5. Jena: Gustav Fischer.

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.

Summary

Thanks CD for German translation of Origin.

Droughts over the summers have brought about changes in the numbers of plants and animals in the area. The small quantity of Orchestia darwinii that has survived the changes no longer includes two previously common male forms. Great changes also take place without such unusual physical conditions. The disappearance of a briefly abundant bryozoan in local caves has made way not for the return of original bryozoan inhabitants but for a completely new fauna.

Letter details

Letter no.
DCP-LETT-5027A
From
Johann Friedrich Theodor (Fritz) Müller
To
Charles Robert Darwin
Sent from
Desterro, Brazil
Source of text
Möller ed. 1915–21, 2: 80–2
Physical description
inc (German trans)

Please cite as

Darwin Correspondence Project, “Letter no. 5027A,” accessed on 29 March 2024, https://www.darwinproject.ac.uk/letter/?docId=letters/DCP-LETT-5027A.xml

Also published in The Correspondence of Charles Darwin, vol. 14

letter