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GENERAL APPENDIX

TO THE

REPORT FOR 1868.

The object of this appendix is to illustrate the operations of the Institution by reports of lectures and extracts from correspondence, as well as to furnish information of a character suited especially to the meteorological observers and other persons interested in the promotion of knowledge.

MEMOIR OF CUVIER.

BY M. FLOurens.

Translated for the Smithsonian Institution by C. A. Alexander.

When a nation loses one of those men whose sole name would suffice for its own glory and that of an epoch, the grief which it feels is so profound that voices are raised on all sides to deplore the common calamity. There is a general emulation to pour forth the public regret at their tomb; a universal impulse to make known all that can be learned respecting lives so illustrious and so honorable to humanity.

So it should have been, and so in effect it has been in regard to M. Cuvier. Men of science, men of letters, whole Academies, indeed, have already published accounts of his life and person, and it would be too late to-day for the Academy of Sciences to say anything new of the great man whom it has lost. But, among the labors on which rests his renown, there are such as pertain more specially to this Academy, and the study of which is far from being exhausted. I allude to the progress which the natural sciences owe to M. Cuvier, a progress which has renovated all those sciences, and which has so greatly extended them that it has in reality extended, through them, the reach of the human mind and the domain of genius.

In M. Cuvier, therefore, I consider here only the savant, and even in the savant shall, above all, consider the naturalist. Fontenelle said, in his account of Leibnitz, that he had been obliged, in some sort, to divide and decompose that great man; and that quite the contrary of antiquity, which had made one Hercules out of many, he had made of Leibnitz alone, many savants. So it is necessary to decompose M. Cuvier, if we would at all measure his genius; this great intellect which, like that of Leibnitz, "conducted all the sciences abreast," and which, not restricting itself to the sciences, diffused its light on the highest institutions of the state, requires, in order to be properly comprehended, as many separate discussions as it has manifested different capacities. I repeat, therefore, that I here consider in M. Cuvier only the naturalist; but even so, my task will be immense, and, in venturing to approach it, I need all the indulgence of those to whom I address myself.

The history of M. Cuvier, if we recall all that the natural sciences owe to him, is scarcely less in fact than the history of those sciences in the earlier part of the nineteenth century. The eighteenth had already communicated to them a rapid movement in advance. Two individuals, Linnæus and Buffon, had especially co-operated in producing this movement; and although endowed otherwise with very different qualities, it is to be remarked, nevertheless, that it was from the same cause that both had failed in their aim. Those phenomena, in effect, those beings, those facts, which the comprehensive genius of Linnæus sought to distinguish and to classify; those facts which the soaring genius of Buffon sought to combine and to explain, were not yet sufficiently known in their intimate nature to supply either their true classification or their real explana

tion.

The primary merit of M. Cuvier, and it was by this merit that he communicated from the first a new life to the natural sciences, was the distinct perception

* Read before the Academy of Sciences, 29th December, 1834.

that the classification as well as explanation of facts could be founded only on their inmost nature thoroughly understood. In a word, and taking into view only the natural history of animals, that branch of natural history in general which M. Cuvier has most directly elucidated by his labors, it is evident that what had been wanting to Linnæus and to Buffon, whether for the classification of animals or for the proper explanation of their phenomena, was the adequate knowledge of their internal structure or organization; and it is not less evident that the laws of all classification, as of the whole natural philosophy of these beings, could spring only from the laws of that organization itself.

It will presently be seen that it was by the assiduous study of these fruitful laws that M. Cuvier renovated in succession zoology and comparative anatomy; that he renovated them one by means of the other; and that he founded on both the science of fossil animals-a science altogether new, wholly due to his genius, and which has thrown light in its turn on the science of the earth itself. But before we come to these last and astonishing results, the fruits of so many grand conceptions and so many unexpected discoveries, let us first see what he has done in particular for each of the sciences just mentioned, in order that we may afterward be better able to comprehend and embrace in a general view what he has done for all. I commence with zoology..

Linnæus, who of all the naturalists of the eighteenth century had exerted the most general influence on the human mind, particularly in point of method, divided the animal kingdom into six classes: quadrupeds, birds, reptiles, fishes, insects, and worms. In this Linnæus committed a first general error, for in placing in the same line these six primitive divisions, he assumed that an equal interval separated them one from another; than which nothing could be less exact. On the other hand, almost all these classes, especially the last, at one time separate animals the most nearly related, at another unite those which are most incongruous. In a word, classification, which has no other end but to mark the true relations of beings, in this instance almost everywhere severed those relations; and that instrument of method which only serves the understanding in so far as it conveys just ideas of things, communicated to it, nearly throughout, only false ideas.

This whole classification of Linnæus was, therefore, to be recast, and nearly the entire framework of the science to be reconstructed. Now, to attain this end, it was first necessary to found the classification on organization, for it is organization alone which gives the true relations; in other terms, it was necessary to found zoology on anatomy; it was next necessary to introduce into the method itself views more just and elevated than had been previously applied. It was, in effect, these elevated views as regards method, these profound studies on organization, which shone forth in the first labors of M. Cuvier : potent resources, by means of which he succeeded in effecting successively the reform of all the branches of zoology, one after the other, and in finally renovating in its whole extent that vast and grand science.

I have said that it was chiefly in the class vermes of Linnæus that disorder and confusion prevailed. He had thrown into it all animals with white bloodthat is to say, more than half the animal kingdom. It was in the first of his memoirs, published in 1795, that M. Cuvier pointed out the great difference of the beings till then confounded under this vague name of white-blooded animals, and that he separated them with precision from one another, first into three great classes: Mollusks, which, like the poulp, the cuttle-fish, the oyster, have a heart, a complete vascular system, and respire by means of branchia or gills; insects, which have, in place of a heart, only a simple dorsal vessel, and respire by tracheæ; and, lastly, zoophytes-animals whose structure is so simple as to have gained them this name, signifying animal plants, and which have neither heart, nor vessels, nor distinct organ of respiration. By subsequently forming three other classes-vermes, crustacea, echinodermata-all the animals with white

blood are found to be distributed into six classes: mollusks, crustaceans, insects, worms, echinoderms, and zoophytes.

Everything was new in this distribution; but everything was at the same time so evident that it was generally adopted, and thenceforward the animal kingdom assumed a new face. Moreover, the precision of the characters on which each of these classes was founded, the perfect conformity of the beings which were assembled under each of them, could not but prove convincing to naturalists; and what doubtless appeared to them not less worthy of admiration than these direct and immediate results, was the sudden light which thereby broke on the highest points of the science-the grand ideas on the subordination of the organs and on the office of this subordination in their employment as characters-those great laws of the animal organization thus and so early apprehended: that all animals with white blood which have a heart have also branchiæ or a circumscribed respiratory organ; that all those which have no heart have only a trachea; that wherever the heart and the branchiæ exist, the liver exists; that wherever they are wanting the liver is wanting.*

Assuredly, no one had as yet thrown a glance so comprehensive, so penetrating on the general laws of the organization of animals, and it was easy to foresee that if he should pursue the investigation of those laws with anything like the same continuity, Cuvier, whose first views had imparted to science so brilliant an impulse, would not be long in extending its boundaries in every direction. He has often recalled since, and even in his last works, this first memoir, from which, in truth, date the germs both of the grand renovation which he effected in zoology and of the greater part of his most fundamental ideas in comparative anatomy.

Never, indeed, had the domain of a science been so rapidly augmented. With the exception of Aristotle, whose philosophic genius had neglected no part of the animal kingdom, scarcely had any one studied, at any epoch, more than the vertebrate animals alone, at least in a general and thorough manner. The animals with white blood, or, as M. Lamarck has since called them, the animals without vertebræ, formed in some sort a new animal kingdom, almost unknown to naturalists, and of which M. Cuvier had at once revealed to them as well the different plans of structure as the particular laws to which each of these plans is subjected. All these animals--so numerous, so varied in their forms, and the knowledge of which has since so greatly extended the basis of general physiology and natural philosophy-were then of scarcely any account to the physiologist and the philosopher; and even long after these great labors of M. Cuvier of which I speak, how many systems have we not seen which, pretending to embrace under one sole point of view the entire animal kingdom, have embraced in reality only the vertebrata? So vast was the new route which he had traced for naturalists, and so difficult was it found to follow him therein, on account of its very vastness.

In this first memoir, then, M. Cuvier had succeeded in finally establishing the true division of animals with white blood. In a second, taking up specially one of their classes, that of the mollusks, he laid the foundations of his great work on those animals-a labor which occupied him for so many years, and which has produced an assemblage of results the most surprising, perhaps, and at least the most essentially new of all modern zoology, as of all modern comparative anatomy.

Till then there had been no example of an anatomy so exact and bearing on so great a number of fine and delicate parts. Daubenton, that model of precis ion and exactness, had scarcely described with equal detail more than the skeleton and the viscera of quadrupeds; here there was the same attention and a

* By the liver I mean a massive and compact organ, a conglomerate gland; in insects the secretions in effect are accomplished simply by tubes very long and slender, which float in the interior of the body and are fixed only by the trachea.

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