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Darwin Correspondence Project

From Joachim Barrande1   19 June 1870

Prague | 419-Kleinseite | Choteksgasse

19 Juin 1870—

Très honoré mâitre,

Au moment où votre aimable lettre du 28 Mai dernier m’est parvenue, je terminais les pages ci-jointes, en réponse à un géologue français, qui m’avait fait part de ses impressions après la lecture de mon travail sur la distribn des Cèphalop. silur.2

Bien que ces pages ne soient pas destinées à être publieés, je me ferais un scrupule de courtoisie de les envoyer à leur destination, sans vous les communiquer. J’espère que vous excuserez mon scrupule, si ces pages renferment quelques circonstances, qui pourraient ne pas avoir attiré jusqu’ici votre attention.

Dans tous les cas, je suis hereux de saisir cette occasion, pour vous exprimer ma sincère et profonde admiration pour tant de travaux variés, par lesquels vous avez enrichi la science et que personne ne saurait apprécier plus haut que moi.

Agréez, très honoré Mâitre, l’expression de mes sentimens les plus distingués. | J Barrande

[Enclosure]

Prague

14 juin 1870—

Copie.

Monsieur et très honoré confrére,

Je loue hautement la loyale franchise avec laquelle vous reconnaissez que les résultats de mes études sur les Céphalop. silur. gênent vos convictions, au sujet de la doctrine de la filiation et de la transformation, que vous avez adoptée.

Puis que vous vous proposez de chercher une solution entièrement satisfaisante du problême de l’apparition successive des êtres organisés, en partant du principe théorique en question, j’appèle votre attention sur qq faits qui semblent rebelles à cette théorie.

D’après les vues actuelles des transformistes, Eozoon serait le premier type connu, ou la première souche de tous les animaux.3

Or, vous savez comme moi, combien ce type primitif se rapproche de celui des Polypiers,4 par tous les élémens de sa structure. On peut dire, qu’entre Eozoon et les Polypiers, il n’y a qu’un pas à faire, dans la voie de la filiation et de la transformation. D’après les idées théoriques, ce pas aurait dû aussi être le premier fait dans cette voie. Les Polypiers auraient donc dû couvrir le fond des mers, après l’époque Eozoique et avant la prédominance des autres types d’une organisation plus élevée.

En dépit de cette vraisemblance théorique, on n’a découvert aucune trace de Polypiers calcaires, ni dans les roches qui renferment Eozoon, ni dans les terrains nommés antéprimordiaux, ni même sur l’horizon de la faune primordiale silurienne, faune qu’on nous dit relativement récente par rapport aux âges Eozoiques. On n’aperçoit les premiers vestiges de ces Polypiers que tardivement, c. à d. dans la faune seconde silurienne et leur grand développemt n’a lieu que dans la faune troisième et dans les âges postérieurs.

Il serait difficile de croire, que leurs traces ont partout disparu dans les formations antérieures à la faune seconde silurienne, car, en raison de leur nature calcaire, ils auraient pu se conserver au moins aussi bien que les restes délicats et microscopiques d’Eozoon.

Par contraste, les dépouilles des Trilobites se montrent avec une fréquence incomparable dans toutes les régions des deux continens, sur l’horizon le plus profond qui ait fourni une faune, c. à d. sur l’horizon de la faune prémordiale silurienne.

Pourquoi l’enveloppe fragile de ces Crustacés a-t-elle joui de ce privilège de conservation, si l’enveloppe massive des Polypiers contemporains ou antérieurs a réellement disparu, dans toutes les contrées explorées.

Si l’on considère, que la faune primordiale se trouve bien développée dans un grand nombre de pay〈s〉 géographiquement très espacés, on doit se demander, pourquoi presque tous les descendans d’Eozoon, après mille transformations supposées, durant l’immense série des âges antéprimordiaux, et sous l’influence des circonstances les plus diverses, se sont pour ainsi dire donné le mot, pour aboutir en même temps au même type trilobitique, si bien caractérisé et si concordant sur tout le globe, malgré ses variations locales. Ce fait singulier mérite bien d’être expliqué par les théories.

Remarquons aussi que, dans la faune primordiale on trouve avec les Trilobites quelques autres types, fournissant des individus relativement rares. Ce sont principalement des Brachiopodes et des Ptéropodes, qui représentent les Mollusques à coté des Articulés.

Si tous ces types sont réellement dérivés d’un prototype commun, leur coexistence se manifestant uniformément partout où l’on rencontre la faune primordiale, nous induirait à croire, qu’ils sont les plus rappr〈o〉chés par leur organisation, parmi les articulés et les Mollusques, puisqu’ils sont les plus rapprochés par la filiation de leur source commune. Mais les zoologues nous démontreront-ils cette affinité relative entre les Trilobites, Brachiopodes et Ptéropodes?

En admettant la commune descendance de tous ces types, à partir d’un même prototype, il resterait encore la difficulté que la théorie rencontre à chaque pas, c. à d. la disparition inexplicable de toutes les formes intermédiaires entre Eozoon et chacun des types primordiaux. Ces formes auraient dû être représentées par d’innombrables individus, durant l’ère antéprimordiale. La théorie peut-elle rendre compte de cette invariable disparition dans tous les pays, lorsqu’elle invoque partout la conservation d’Eozoon?

Le doute fort que la transformation brusque par accident, qui vous semble promettre une plus heureuse solution que la transformation lente, puisse mieux satisfaire à l’explication de tous ces faits.

Introduire des accidens quelconques comme cause de l’apparition des types successifs, c’est attribuer ces apparitions au hazard. Mais, qui oserait invoquer le hazard comme ordonnateur du développement graduel de la série animale, lorsque, aux yeux de tous les hommes de science, cette série présente les résultats d’un plan unique, merveilleusement exécuté, malgré tous les troubles subis par l’écorce terrestre et par tous les élémens matériels, au milieu desquels la vie a dû se propager.

Je termine en vous souhaitant les plus ingénieuses et les plus heureuses conceptions, dans votre future théorie. Mais vous ne trouverez pas mauvais que je vous répète ce que j’ai déjà exprimé dans mon dernier travail sur les Céphalopodes: Je n’ai pas l’espoir que l’esprit humain parvienne à pénétrer le mystère qui enveloppe la première apparition et la succession des formes de la vie sur notre globe.

Agreez &c | J B

P. S— Vous recevrez prochainement ma défense des Colonies—IV5 et vous trouverez que j’ai constaté (p. 145–) ce fait remarquable: que certains Trilobites de Bohême, offrant diverses oscillations de forme, sont revenus à leur forme primitive, après un long intervalle de temps. Ces faits méritent attention, parcequ’ils nous font concevoir, que les modifications de forme produites sous l’influence de l’homme, pourraient n’être réellement que des oscillations temporaires.

Footnotes

For a translation of this letter, see Correspondence vol. 18, Appendix I.
CD’s letter to Barrande of 28 May 1870 has not been found. Barrande refers to Barrande 1870. The geologist has not been identified.
Barrande presumably refers to Eozoon canadense. In 1864, John William Dawson identified samples taken from pre-Silurian strata in eastern Canada as fossilised Foraminifera, single-celled protists with shells; he named the species Eozoon canadense, the ‘Dawn animal from Canada’ (Dawson 1864). Further samples were sent to William Benjamin Carpenter, an expert on Foraminifera, who confirmed Dawson’s interpretation (Carpenter 1864). CD added information on the discovery of Eozoon canadense to Origin 4th ed., p. 371, as substantiating his claim, made in Origin, p. 307, that life existed before the Silurian period. The interpretation of the samples as pre-Silurian fossils remained controversial, however (see, for example, Carpenter 1866, and King and Rowney 1866); and by the end of the century, comparisons with similar, more recent, formations indicated that the samples were mineral in origin (see Schopf 2000).
Polypiers (French) or polypidoms (English) are now (in English) polypariums. A polyparium is ‘the common stem or supporting structure of a colonial cnidarian (or other colonial invertebrate), to which the individual polyps are attached’, or (an obsolete meaning) a colonial cnidarian (OED).
Barrande refers to the fourth volume of Barrande 1861–81.

Translation

From Joachim Barrande1   19 June 1870

Prague | 419-Kleinseite | Choteksgasse

19 June 1870—

Most honoured master,

At the moment when your kind letter of 28 May ult. reached me, I was finishing these pages attached, in reply to a French geologist, who had informed me of his impressions after reading my work on the distribn of Cephalop. Silur.2

Even though these pages are not intended to be published, I would have had doubts about the courtesy of sending them to their destination without communicating them to you. I hope you will excuse my scruples, if the pages contain some circumstances that were not able to be brought thus far to your attention.

In any case, I am happy to take this opportunity, to express to you my sincere and profound admiration for such varied works, through which you have enriched science and which no one would appreciate more highly than me.

Accept, most honoured master, the expression of my most distinguished sentiments. | J Barrande

[Enclosure]

Prague

14 June 1870—

Copy.

Sir and most honoured colleague,

I highly praise your straightforward candour in recognising that the results of my studies on the Cephalop. Silur. upset your convictions concerning the doctrine of filiation and transformation, which you have adopted.

Since you intend to seek an entirely satisfying solution to the problem of successive appearance of organic beings, following from the theoretical principle in question, I call your attention to certain facts which seem unamenable to this theory.

According to the current views of transformists, Eozoon would be the first known type, or the first stock of all the animals.3

Now you know, like me, how the primitive type approaches that of the Polypidoms,4 especially the elements of its structure. One could say, that between Eozoon and the Polypidoms, there is only one step to take, in the route of filiation and of transformation. According to the theoretical ideas, this step would also have had to be the first made along this path. The Polypidoms then would have to have covered the sea floor, after the Eozoic era and before the predominance of other types of higher structure.

In spite of this theoretical verisimilitude, one has not recovered any trace of calcareous Polypidoms, neither in the rocks that contain Eozoon, nor in the earths called anteprimordial, nor even on the horizon of the primordial Silurian fauna, fauna one tells us is relatively recent in relation to the Eozoic eras. One only perceives the first vestiges of these Polypidoms belatedly, that is to say, in the second silurian fauna and their great development has no place except in the third fauna and subsequent eras.

It would be difficult to believe, that their traces have everywhere disappeared in formations before the second Silurian fauna, for, by reason of their calcareous nature, they would be preserved at least as well as the delicate and micoscopic remnants of Eozoon.

By contrast, the remains of Trilobites appear with frequency incomparable in all regions of the two continents, on in the most distant reaches where a fauna has been found, that is to say on the horizon of the primordial Silurian fauna.

Why did the fragile wrapping of these Crustaceas enjoy the privilege of preservation, if the sturdy wrapping of the Polypidoms, contemporary or previous, actually disappeared, in all regions that have been explored.

If one considers that the primordial fauna is found well developed in a large number of countries geographically very separated, one must ask, why do all the descendants of Eozoon, after a thousand supposed transformations, over an immense sequence of anteprimordial ages, and under the influence of the most diverse circumstances, were then so to speak given the word, to converge at the same time into the same trilobitic type, so well characterised and so uniform around the whole world, despite its local variations. This singular fact well merits explanation by your theories.

Let us also note that, in the primordial fauna the Trilobites are found amongst some other types, providing relatively rare individuals. These are primarily Brachiopods and Pteropods, which represent the Molluscs next to the Articulata.

If all these types are truly derived from a common prototype, their coexistence manifesting uniformly everywhere one encounters primordial fauna, we are led to believe that they are the most related by their structure among the articulata and the Molluscs, since they are the most related by the filiation of their common source. However, do zoologists show us this relative affinity between Trilobites, Brachiopods and Pteropods?

While admitting the common descent of all these types from the same prototype, there still remains the difficulty that the theory encounters at each step, that is, the inexplicable disappearance of all intermediate forms between the Eozoon and each of the primordial types. These forms would have to have been represented by innumerable individuals during the anteprimordial era. Can the theory account for this invariable disappearance in all countries, while it puts forth the preservation of Eozoon?

It is highly doubtful that an abrupt transformation by chance, which would seem to offer a happier solution than slow transformation, could be a more satisfactory explanation of all the facts.

To introduce any accidents whatever as a cause of the appearance of successive types, is to attribute these appearances to chance. However, he who ventures to invoke chance as an organizer of the gradual development of the animal sequence, when, to the eyes of all men of science, this sequence presents the results of a unique plan, marvellously executed, despite all the troubles undergone by the terrestrial crust and by all the material elements, amidst which life had to spread.

I end by wishing you the most ingenious and happy ideas, in your future theory. But you will not find it bad that I repeat to you that which I have already expressed in my last work on the Cephalopods: I do not hope that the human spirit will finally penetrate the mystery that envelops the first appearance and the succession of the forms of life on our planet.

Accept &c | J B

P.S— You will soon receive next my Défense des Colonies—IV5 and you will find that I have established (p. 145–) this remarkable fact: that certain Trilobites of Bohemia, offering various oscillations of form, returned to their primitive form, after a long interval of time. These facts merit attention, since they make us imagine that the modifications of form produced under the influence of man, could not be in truth anything but temporary oscillations.

Footnotes

For a transcription of this letter in its original French, see pp. 169–71.
CD’s letter to Barrande of 28 May 1870 has not been found. Barrande refers to Barrande 1870. The geologist has not been identified.
Barrande presumably refers to Eozoon canadense. In 1864, John William Dawson identified samples taken from pre-Silurian strata in eastern Canada as fossilised Foraminifera, single-celled protists with shells; he named the species Eozoon canadense, the ‘Dawn animal from Canada’ (Dawson 1864). Further samples were sent to William Benjamin Carpenter, an expert on Foraminifera, who confirmed Dawson’s interpretation (Carpenter 1864). CD added information on the discovery of Eozoon canadense to Origin 4th ed., p. 371, as substantiating his claim, made in Origin, p. 307, that life existed before the Silurian period. The interpretation of the samples as pre-Silurian fossils remained controversial, however (see, for example, Carpenter 1866, and King and Rowney 1866); and by the end of the century, comparisons with similar, more recent, formations indicated that the samples were mineral in origin (see Schopf 2000).
Polypiers (French) or polypidoms (English) are now (in English) polypariums. A polyparium is ‘the common stem or supporting structure of a colonial cnidarian (or other colonial invertebrate), to which the individual polyps are attached’, or (an obsolete meaning) a colonial cnidarian (OED).
Barrande refers to the fourth volume of Barrande 1861–81.

Summary

Encloses a copy of a letter he has written to a French geologist. In it he raises objections to evolutionary theory:

why are corals inadequately represented in the fossil record?

How can one explain the widespread appearance and then disappearance of groups like the trilobites?

If Mollusca and Articulata have a common ancestor, why are not ancient forms more akin than present ones?

Letter details

Letter no.
DCP-LETT-7236
From
Joachim Barrande
To
Charles Robert Darwin
Sent from
Prague
Source of text
DAR 160: 44–5
Physical description
1p, encl 4pp (French)

Please cite as

Darwin Correspondence Project, “Letter no. 7236,” accessed on 18 March 2019, http://www.darwinproject.ac.uk/DCP-LETT-7236

Also published in The Correspondence of Charles Darwin, vol. 18

letter