It is impossible to study Aristotle's Natural History Treatises and not be convinced that he borrowed largely from his predecessors. It is probable that his observations on human anatomy and physiology were derived in great measure from the writings of the illustrious Hippocrates, the Father of Medicine, and from the information, whether oral or written, obtained from his own father Nicomachus, who was physician in ordinary to the King of Macedon, Amyntas II., and who was himself, as Stahr informs us, the author of several treatises on subjects connected with natural science.'

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Do we detract aught from the fame of Aristotle when we assert that his History of Animals' is largely indebted to the labours of others? Did not Cuvier acknowledge his obligations to his predecessors in the field of zoological science, to Lacépède, Levaillant, Blainville, Geoffroy St. Hilaire, and a host of others? Has Cuvier's fame thereby decreased? Is it possible that the life of a man, the author of so many and various learned works, who died at sixty-two, could have sufficed for the observation of such a mass of recorded facts? Does the evidence of the existence of much error and want of investigation in Aristotle's Natural History writings close our eyes to the greatness of his intellect, and to the fact that those very writings contain vast stores of interesting matter which evince the brilliancy of his genius, the originality of his mind, and the philosophic combination of his ideas?

With regard to the question of the formation of a systematic classification by Aristotle, people's views differ so widely as to be almost irreconcilable; for while some maintain, as Külb has remarked, that Aristotle purposely abstained from forming any system, in order not to prejudice the more accurate conclusions of better and later wisdom, or at least laid down no such marked distinctions, as we fancy we perceive in his writings, and had merely a vague general idea of classification, which as little resembled a system as a mere jotting down of all the letters of the alphabet would resemble an essay; others are resolved to discover a system so perfect that it leaves to us little to alter in it.' Nothing can be more erroneous than this latter view, which has been so successfully combated by Dr. Whewell more than twenty years ago, that it is a wonder to find it still maintained by some writers. Were it a fact that Aristotle's classification is in many respects 'superior to some of the most admired and recent attempts of modern times,' the law of evolution, upon which we have laid so much stress, would be materially interfered with, or indeed completely destroyed. But in reality,' we now quote Dr. Whewell's words—

The

The statements to which we refer respecting the scientific character of Aristotle's zoological system are altogether without foundation, and this science confirms the lessons taught us by all the others. . . Aristotle's nine books "On Animals are a work enumerating the differences of animals in almost all conceivable respects; the organs of sense, of motion, of nutrition, the interior anatomy, the exterior covering, the manner of life, growth, generation, and many other circumstances. These differences are very philosophically estimated. . . . . Aristotle proceeds to state his object, which is, to describe the differences of animals in their structure and habits. He then observes that for structure we may take man for our type, as being best known to us. The authors of this "Systema Aristotelicum" have selected, I presume, the following passages from the work "On Animals," as they might have selected any other; and by arranging them according to a subordination unknown to Aristotle himself, have made for him a scheme which undoubtedly bears a great resemblance to the most complete system of modern times :

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Book I. chap. v.-"Some animals are viviparous, some oviparous, some vermiparous. The viviparous are such as man, and the horse and all those animals which have hair; and of aquatic animals, the whale-kind, as the dolphin and cartilaginous fishes."

'Book II. chap. vii.-" Of quadrupeds which have blood and are viviparous, some are (as to their extremities) many-cloven, as the hands and feet of man. For some are many-toed, as the lion, the dog, the panther; some are bifid, and have hoofs instead of nails, as the sheep, the goat, the elephant, the hippopotamus; and some have undivided feet, as the solid-hoofed animals, the horse and the ass. The swine-kind share both characters."

‘Chap. ii.—“ Animals have also great differences in the teeth, both when compared with each other and with man. For all quadrupeds which have blood and are viviparous have teeth; and, in the first place, some are ambidental (having teeth in both jaws), and some are not so, wanting the front-teeth in the upper jaw. Some have neither front-teeth nor horns, as the camel; some have tusks, as the boar, some have not. Some have serrated teeth, as the lion, the panther, the dog; some have the teeth unvaried, as the horse and the ox; for the animals which vary their cutting teeth have all serrated teeth. No animal has both tusks and horns; nor has any animal with serrated teeth either of those weapons. The greater part have the front-teeth cutting and those within broad."

These passages undoubtedly contain most of the differences on which the asserted Aristotelian classification rests; but the classification is formed by using the characters drawn from the teeth, in order to subdivide those taken from the feet, whereas, in Aristotle, these two sets of characters stand side by side, along with dozens of others; any selection of which, employed according to any arbitrary method of subordination, might with equal justice be called Aristotle's system. Why, for instance, in order to form subdivisions of animals, should we not go on with Aristotle's continuation of the second of the above

quoted

quoted passages, instead of capriciously leaping to the third. "Of these some have horns, some have none. . . Some have a fetlockjoint, some have none. .. Of those which have horns, some have them solid throughout, as the stag; others, for the most part, hollow. . . . . Some cast their horns, some do not." If it be replied, that we could not by means of such characters form a tenable zoological system, we again ask by what right we assume Aristotle to have made or attempted a systematic arrangement, when what he has written, taken in its natural order, does not admit of being construed into a system?

'Again, what is the object of any classification? This, at least, among others: To enable the person who uses it to study and describe more conveniently the objects thus classified. If, therefore, Aristotle had formed or adopted any system of arrangement, we should discover it in the order of the subjects in his work. Accordingly, so far as he has a system, he professes to make use of it. At the beginning of the fifth book, where he is proceeding to treat of the different modes of generation of animals, he says, "As we formerly made a division of animals according to their kinds, we must now in the same manner give a general survey of their history. Except, indeed, that in the former case we made our commencement by a description of man; but in the present instance we must speak of him last, because he requires most study. We must begin, then, with those animals which have shells (testaceous molluscs); we must go on to those which have softer coverings (crustacea), then to the cephalopoda and annulose animals; after this to fishes, both viviparous and oviparous, then to birds, then to land-animals, both viviparous and oviparous.'

'It is clear,' Dr. Whewell continues, that Aristotle had certain wide and indefinite views of classification, which, though not very exact, are still highly creditable to him; but it is equally clear that he was quite unconscious of the classification that has been ascribed to him. .. The honour due to the stupendous accumulation of zoological knowledge, which Aristotle's works contain, cannot be tarnished by our denying him the credit of a system which he never dreamt of, and which from the nature of the progress of science could not possibly be constructed at that period. But, in reality, we may exchange the mistaken claims which we have been contesting for a better, because a truer, praise. Aristotle does show, as far as could be done at his time, a perception of the need of groups, and of names of groups, in the study of the animal kingdom: and thus may justly be held up as the great figure in the prelude to the formation of systems which took place in more advanced scientific times.'*

We have given at some length Dr. Whewell's remarks on this point. They evince great powers of discernment, and are incontrovertible. But although we deny to Aristotle the formation of any grand philosophical system of classification, we must not

*See History of Inductive Sciences,' iii. pp. 344-355.

suppose

suppose that he had none at all. There appear certain indications that he adopted the one in general use amongst his contemporaries, such as it was; we regard this early prelude to the formation of a zoological system rather as the exposition of the knowledge and opinions of others than his own; he very frequently in the course of his writings refers to certain groups or families which he says are without a name,' 'have never received any name.' Now it is observable that Aristotle never proposes names for these anonymous groups. He adopts the current nomenclature without alteration or addition. He employs only two formal terms of classification, namely, yévos and eldos. The former term denotes an assemblage of different species having some general resemblance to one another; it may be synonymous with the modern terms, family, order, or class; the latter term is usually, though not exclusively, applied to what modern naturalists commonly understand by species.

The first great division in the classification of Aristotle is made between 'animals that have red blood' (evaipa) and 'those whose blood or vital fluid is not red' (avaipa). It is incorrect, we think, to suppose that the avaiμa were regarded by Aristotle as being entirely destitute of a vital fluid analogous to blood. He states that every living creature is furnished with moisture, the loss of which occasions death. In some animals this moisture is found in the blood and veins; in others the situation is analogous only; but these are imperfect as fibres and serum. The red-blooded animals were divided into (1) Viviparous and Oviparous Quadrupeds, (2) Birds, (3) Fishes, (4) the Cetacea, and perhaps (5) Serpents. These are the principal classes (yevn μέγιστα τῶν ζώων εἰς ἃ διαιρεῖται τἄλλα ζώα). Of the ἄναιμα, or animals without red blood, the following are the great divisions, though some of these were without recognised names:— (1.) A class of animals covered with a shell (Tò Tv Oσтракоdépμwv yévos) called shell-fish (öσTρeov); this corresponds to the testaceous molluscs of modern naturalists. (2.) Animals having a soft shell (τὸ τῶν μαλακοστράκων γένος), such as crabs, lobsters, &c.; this division had no recognised name, it answers to our Crustacea. (3.) Soft-bodied Mollusca (Tò Tŵv μaλakiwv), such as the teuthis and sepia (cuttle-fish); this division corresponds with the Cephalopoda of the moderns. (4.) Annulose animals (Tò Tv evróμwv), such as bees, scolopendra, corresponding generally with the Insecta and partly with the Annulata of present zoologists. Aristotle, it is true, hints at further division of these great groups, but we nowhere find that he proposes any systematic arrangement of them into sub-orders, families, &c.

The whole history of Zoology points unmistakeably to the

gradual

gradual evolution of the great truths of the science: our present knowledge, imperfect it is true, is the result of the accumulated efforts of many labourers in the wide field of nature; 'not only labour but time, not only one man of genius but several, and those succeeding each other, are requisite to the formation of any considerable science.' To Aristotle and Gesner, Marcgrave, Śwammerdam, Willugby, Ray, Harvey, Linnæus, Cuvier, Hunter, Milne Edwards, Owen, Huxley, and a host of other celebrities, the science of Zoology is indebted-to some of these, doubtless, more than to others, but still to all she owes something; each earnest inquirer into the truths which Nature has to reveal has it in his power to add some trifling contribution to the general

cause.

Aristotle was well aware of the great difficulty in deciding whether certain organisms belonged to the vegetable or animal kingdom. The following passage is extremely interesting:

Nature passes so gradually from inanimate to animate things that from their continuity, their boundary, and the mean between them is indistinct. The race of plants succeeds immediately that of inanimate objects, and these differ from each other in the proportion of life in which they participate, for compared with other bodies, plants appear to possess life, though when compared with animals, they appear inanimate. The change from plants to animals, however, is gradual, as I before observed. For a person might be in doubt with regard to some things that are found in the sea whether they are animals or plants; for many of them are attached to the rock and perish as soon as they are separated from it. The pinnæ are attached to the rocks, the solens cannot live after they are taken away from their localities; and on the whole, all the testacea resemble plants, if we compare them with locomotive animals; some of them appear to have no sensation; in others it is very dull. The body of some of them is naturally fleshy, as of those which are called tethya (Ascidian molluscs); and the acalephe (actinia) and the sponge entirely resemble plants.'

Aristotle believed in spontaneous generation-an opinion, we may observe, which has been revived in modern times and defended with considerable ability :

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'It is evident,' he says, that some fish are of spontaneous birth and do not originate from ova. Those which are neither oviparous nor viviparous are all produced from mud or sand, or from the putrid matter on the surface, as also the foam in sandy places produces the aphya. This aphya never increases in size, and is barren, and as time advances it perishes and another fry is formed. . . . this is a proof that it sometimes originates in the soil, for it is not captured by fishermen in cold weather, but on a fine day it may be taken as it comes up from the ground for the sake of the warmth; when they have dragged the ground and scraped up the surface the fish are more

numerous