The Atlantic Monthly, Volume 09, No. 51, January, 1862

been accumulated, and how those facts have been converted into science. In so doing, I shall present the methods employed in Natural History on a wider scale and with broader generalizations than if

in their first attempts to understand the world in which they live. But these efforts, that appear childish to us now, were the

work on Natural History is a record not only of his own investigations, but of all preceding study in this department. It is evident that even then much had been done, and, in allusion to certain peculiarities of t

names; and of his descriptions of their habits and peculiarities, much is lost upon us from their local character and expression. There is also a total absence of systematic form, of any classification or framework to express the divisions of the animal kingdom into larger or lesser groups. His only divisions are genera and species: classes, orders, and families, as we understand them now, are quite foreign to the Greek conception of the animal kingdom. Fishes and birds, for instance, they considered as genera, and their different representatives as species. They grouped together quadrupeds also in contradistinction to animals with legs and wings, and they distinguished those that

e that Aristotle recorded. And though the great naturalists of the sixteenth century gave a new impulse to this study, their investigations were chiefly directed towards a min

, of different weight and value. Besides species and genera, he gives us orders and classes,-considering classes the most comprehensive, then orders, then genera, then species. He did not, however, represent these groups as distinguished by their nature, but only by their range; they were still to him, as genera an

ternal features as class characters, he excluded many animals which by their mode of reproduction, as well as by their respiration and circulation, belong to this class as much as the Quadrupeds,-as, for instance, all the Cetaceans, (Whales, Porpoises, and the like,) which, though they have not legs, nor are their bodies covered with hair or fur, yet bring forth living young, nurse them with milk, are warm-blooded and air-breathing. As more was learned of these animals, there arose serious discussion and criticism among contemporary naturalists respecting the classification of Linn?us, all of which led to a clearer insight into the true relations among animals. Linn?us himself, in his last edition of the "Systema Natur?," shows us what important progress he had made since he first announced his views; for he there substitut

h to generalize them and give meaning and vitality to the whole. It was Cuvier who found the key. He himself tells us how he first began, in his investigations upon the internal organization of animals, to use his dissections with reference to finding the true relations between animals, and how, ever after, his knowledge of anatomy assisted him in his classifications, and his classifications threw new light again on his anatomical investigations,-each science thus helping to fertilize the other. He was not one of those superficial observers who are in haste to announce every new fact that the

utilité, au plus ou moins de connaissance que nous en avons, ni à toutes les autres circonstances accessoires, on trouvera qu'il existe quatre formes principales, quatre plans généraux, si l'on peut s'exprimer ainsi, d'après lesquels tous les animaux semblent

e before were now at once referred to their true relations with other animals by ascertaining whether they were built on one or another of these plans. Of

ate deep enough into their organization to find the secret of their internal structure. Till he can do this, he is like the traveller in a strange city, who looks on the exterior of edifices entir

me improvements have been made in the details of his classification, all departures from its great fundamen

ts are arranged according to a bilateral symmetry on either side of the body, but the body has but one cavity, and is a soft, concentrated mass, without a distinct individualization of parts. In the Articulates there is but one cavity, and the parts are here again arranged on either side of the longitudinal axis, but in these animals the whol

f his views. Whatever the cause, his principle of classification was not fully appreciated; but it opened a new road for study, and gave us the keynote to the natural affinities among animals. Lamarck, his contemporary, not recognizing the truth of this principle, distributed the animal kingdom into two great divisions, which he calls Vertebrates and Inv

r that of Lamarck, on the absence or presence of a backbone, or that of Ehrenberg, on the differences of the nervous system, cover the same ground. Lamarck attempted also to use the faculties of animals as a groundwork for division among them. But our knowledge of the psychology of animals is still too imperfect to justify any such use of it. His divisions into Apathetic, Sensitive, and Intelligent animals are entirely theoretical. He places, for instance, Fishes and Reptiles among the Intelligent animals, as distinguished from Crustacea and Insect

ety of animals is founded. This result is of greater importance than may at first appear. Upon it depends the question, whether all such classifications represent merely individual impressions and opinions of men, or whether there is really something in Nature that presses upon us certain divisions among animals, certain affinities, certain limitations, founded upon essential principles of organization. Are our systems the inventions of naturalists, or only their reading of the Book of Nature? and can that book have

n a plan and the execution, of a plan. We allow the details to shut out the plan itself, which exists quite independent of special forms.