Chapter III: Part 3

One of the most famous amongst these fabulous animals of the ancients, is the _unicorn_. Even to our own time people have obstinately persisted in searching for it, or, at least, in seeking arguments to prove its existence. Three separate animals are frequently mentioned by the ancients as having only one horn in the middle of the forehead. The _African oryx_, having cloven hoofs, the hair placed in the contrary direction to that of other animals[69], equal in size to the bull[70] or even the rhinoceros[71], and said to resemble deer and goats in form[72]; the _Indian ass_, having solid hoofs; and the _monoceros_, properly so called, whose feet are sometimes compared to those of the lion[73], and sometimes to those of the elephant[74], and which is therefore considered as having divided feet. The one-horned horse[75] and one-horned bull are doubtless both to be referred to the Indian ass, for even the latter is described as having solid hoofs[76]. I would ask, If these animals exist as distinct species, should we not at least have their horns in our collections? And what single horns do we possess, excepting those of the rhinoceros and narwal?

How is it possible, after this, to refer to rude figures traced by savages upon rocks[77]? Ignorant of perspective, and wishing to represent a straight horned antelope in profile, they could only give it a single horn, and thus they produced an oryx. The oryxes, too, that are seen on the Egyptian monuments, are probably nothing more than productions of the stiff style, imposed upon the artists of that country by their religion. Many of their profiles of quadrupeds shew only one fore and one hind leg; and this being the case, why should they have shewn two horns? It may perhaps have chanced that individuals have been taken in the chace, which had accidentally lost one of their horns, as pretty frequently happens to the chamois and saiga: and this would have been sufficient to confirm the error produced by these representations. It is probably in this way that the unicorn has recently been reported to be found in the mountains of Thibet.

All the ancients, however, have not represented the oryx as having only one horn. Oppian expressly gives it several[78], and Ælian mentions oryxes which had four[79]. Finally, if this animal was ruminant and cloven-hoofed, we know assuredly that its frontal bone must have been longitudinally divided into two, and that it could not, as is very justly remarked by Camper, have had a horn placed upon the suture.

But it may be asked, What two-horned animal could have given the idea of the oryx, and presented the characters which it is described as possessing with regard to its conformation, even independent of the notion of a single horn? To this I reply, with Pallas, that it was the straight horned antelope, the _Antilope oryx_ of Gmelin, improperly named _pasan_ by Buffon. It inhabits the deserts of Africa, and must approach the confines of Egypt. It is this animal which the hieroglyphics appear to represent. Its form is nearly that of the stag; its size equals that of the bull; the hair of its back is directed toward the head; its horns form exceedingly formidable weapons, pointed like javelins, and hard as iron; its hair is whitish, and its face is marked with spots and streaks of black. Such is the description given of it by naturalists; and the fables of the Egyptian priests, which have occasioned the insertion of its figure among their hieroglyphics, do not require to have been founded in nature. Supposing, therefore, that an individual of this species had been seen which had lost one of its horns by some accident, it might have been taken as a representative of the whole race, and erroneously adopted by Aristotle, and copied by his successors. All this is possible, and even natural, and yet proves nothing with regard to the existence of a single-horned species.

In regard to the Indian ass, if we attend to the properties ascribed to its horns as an antidote against poison, we shall see that they are precisely the same as those which the eastern nations attribute at the present day to the horn of the rhinoceros. When this horn was first imported into Greece, the animal to which it belonged might still have been unknown. In fact, Aristotle makes no mention of the rhinoceros, and Agatharchides was the first who described it. In the same manner, ivory was in use among the ancients long before they were acquainted with the elephant. It is even possible that some of their travellers might have given to the rhinoceros the name of _Indian ass_, with as much propriety as the Romans denominated the elephant the _bull of Lucania._ Every thing, moreover, that is said of the strength, size, and ferocity of this wild ass of theirs, corresponds very well with the rhinoceros. In succeeding times, naturalists, who had now become better acquainted with the rhinoceros, finding this denomination of _Indian ass_ in the writings of authors who had preceded them, might have taken it, from want of proper examination, for that of a distinct animal; and from the name, they would have concluded the animal should have solid hoofs. There is, indeed, a full description of the Indian ass given by Ctesias[80], but we have seen above that it had been taken from the bas-reliefs of Persepolis, and must therefore go for nothing in the real history of the animal.

When there afterwards appeared more exact descriptions of an animal having a single horn only, but with several toes, a third species would have been made out, to which they gave the name of _monoceros_. These double references applied to the same species, are more frequent among ancient naturalists, because most of their works which have come down to us were mere compilations; even because Aristotle himself has frequently mingled facts borrowed from others with those which he had observed himself; and because the habit of critical examination was then as little known among naturalists as among historians.

From all these reasonings and digressions, it may be fairly concluded, that the large animals of the old continent with which we are now acquainted, were known to the ancients; and that the animals described by the ancients, and which are now unknown, were fabulous. It also follows, that the large animals of the three principal parts of the then discovered world could not have been long in being known to the nations which frequented their coasts.

It may also be concluded, that no large species remains to be discovered in America. If there were any, there can be no reason why we should not be acquainted with it; and in fact none has been discovered there during the last hundred and fifty years. The tapir, the jaguar, the puma, the cabiai, the llama, the vicuna, the red wolf, the buffalo or American bison, the ant-eaters, sloths and armadilloes, are as well described by Margrave and Hernandez as by Buffon; it may even be said that they are better, for Buffon has confused the history of the ant-eaters, mistaken the jaguar and red wolf, and confounded the bison of America with the aurochs of Poland. Pennant, it is true, was the first naturalist who clearly distinguished the small musk ox; but it was long before made mention of by travellers. The cloven-footed horse of Molina, has not been described by the early Spanish travellers; but its existence is more than doubtful, and the authority of Molina is too suspicious to authorise our adopting it. It might be possible to characterise more accurately than has been done the different species of deer belonging to America and India; but the case is with respect to these animals as it was among the ancients with respect to the antelopes; it is the want of a good method for distinguishing them, and not of opportunities of seeing them, that has left them so imperfectly known to us. It may, therefore, be said, that the Mouflon of the Blue Mountains is the only American quadruped of any considerable size of which the discovery is altogether modern; and even it is perhaps only an argali that may have crossed upon the ice from Siberia.

How should it be thought, after this, that the huge _mastodons_ and gigantic _megatheria_, whose bones have been discovered under ground in North and South America, still exist alive on that continent? How should they have escaped those wandering tribes which continually traverse the country in all directions, and which are themselves aware that these animals no longer exist, since they have invented a fabulous account of their destruction, alleging that they were killed by the Great Spirit, to prevent them from extirpating the human race. But it is evident that this fable has been occasioned by the discovery of the bones, like that of the inhabitants of Siberia with respect to their mammoth, which they pretend to live under ground like the mole, and, like all those of the ancients, about the graves of giants, who were thought by them to have been buried wherever the bones of elephants were discovered.

Thus it may safely be concluded, that if, as we have just said, none of the large species of quadrupeds whose remains are at the present day found in regular mineral strata, bear resemblance to any of the known living species, this is not the effect of mere chance, nor because those species of which we possess nothing but the bones, are still concealed in the deserts, and have hitherto eluded the observation of travellers. On the contrary, this phenomenon must be regarded as resulting from general causes; and its investigation may be considered as affording one of the best means for discovering the nature of these causes.

_Difficulty of determining the Fossil Bones of Quadrupeds._

If this study is more satisfactory in its results than that of other fossil remains of animals, it is also beset with more numerous difficulties. Fossil shells usually present themselves in an entire state, and with all the characters requisite for comparing them with their analogous species, preserved in the collections or figured in the works of naturalists. Even fishes present their skeleton more or less entire; the general form of their body is almost always distinguishable, and most commonly, also, their generic and specific characters, which are drawn from their solid parts. In quadrupeds, on the contrary, even should the skeleton be found entire, it would be difficult to apply to it characters derived, for the most part, from the hair, the colours, and other marks which have disappeared previous to their incrustation. It is even excessively rare to find a fossil skeleton approaching in any considerable degree to a complete state. The strata, for the most part, only contain separate bones, scattered confusedly, and almost always broken, and reduced to fragments; and these constitute the only resources of knowledge to the naturalist in this department. It may also be stated, that most observers, deterred by these difficulties, have passed slightly over the fossil bones of quadrupeds; have classed them in a vague manner, according to superficial resemblances, or have not even ventured to assign them a name; so that this part of the history of fossil remains, although the most important and most instructive of all, is, at the same time, that which has been the least cultivated[81].

_Principle by which this determination is effected._

Fortunately, comparative anatomy possesses a principle, which, when properly developed, enables us to surmount all the obstacles. This principle consists in the mutual relation of forms in organised beings, by means of which, each species may be determined, with perfect certainty, by any fragment of any of its parts.

Every organised being forms a whole,--a peculiar system of its own, the parts of which mutually correspond, and concur in producing the same definitive action, by a reciprocal reaction. None of these parts can change in form, without the others also changing; and consequently, each of them, taken separately, indicates and ascertains all the others.

Thus, if the intestines of an animal are so organised as to be fitted for the digestion of flesh only, and that flesh recent, it is necessary that its jaws be so constructed as to fit them for devouring live prey; its claws for seizing and tearing it; its teeth for cutting and dividing it; the whole system of its organs of motion, for pursuing and overtaking it; and its organs of sense for discovering it at a distance. It is even requisite that nature have placed in its brain the instinct necessary for teaching it to conceal itself, and to lay snares for its victims.

Such are the general conditions which nature imposes upon the structure of carnivorous animals; and which every animal of this description must indispensably combine in its constitution, for without them its race could not subsist. But subordinate to these general conditions, there exist others, having relation to the size, the species, and the haunts of the prey for which the animal is adapted; and from each of these particular conditions, there result modifications of detail in the forms which arise from the general conditions. Thus not only the class, but the order, the genus, and even the species, are found expressed in the form of each part.

In fact, in order that the jaw may be able to seize, it must have a certain form of condyle; that the resistance, the moving power, and the fulcrum, should have a certain relative position in regard to each other; and that the temporal muscles should be of a certain size; the hollow or depression, too, in which these muscles are lodged, must have a certain depth; and the zygomatic arch, under which they pass, must not only have a certain degree of convexity, but it must be sufficiently strong to support the action of the masseter.

In order that the animal may be able to carry off its prey, it must have a certain degree of vigour in the muscles which elevate the head; whence there results a determinate form in the vertebræ from which these muscles take their rise, and in the occiput into which they are inserted.

In order that the teeth may be able to cut flesh, they must be sharp-edged, and must be so in a greater or less degree, according as they have flesh more or less exclusively to cut. Their base will be solid, according to the quantity and size of the bones which they have to break. The whole of these circumstances must necessarily influence the development and form of all the parts which contribute to move the jaws.

In order that the paws may be able to seize the prey, there must be a certain degree of mobility in the toes, and a certain degree of strength in the claws, from which there will result determinate forms in all the phalanges, and a corresponding distribution of muscles and tendons. The fore-arm, or cubitus, must possess a certain facility of turning, from which there will also result determinate forms in the bones of which it is composed. But the bones of the cubitus being articulated to the humerus, a change in the proportions of the former, will necessarily induce a corresponding change in the latter. The shoulder-bones must have a certain degree of firmness in such animals as make use of their fore-legs for seizing, and from this there must also result a certain peculiarity in their form. The play of all these parts will require certain proportions in all their muscles, and the impressions made by these muscles so proportioned, will determine still more particularly the forms of the bones.

It is easy to see that similar conclusions may be drawn with regard to the posterior extremities which contribute to the rapidity of the general motions; with regard to the composition of the trunk, and the forms of the vertebræ, which exert an influence upon the facility and flexibility of these motions; and, lastly, with regard to the forms of the bones of the nose, of the orbit, and of the ear, the connection of which with the perfection of the senses of smell, sight, and hearing, is evident. In a word, the form of the tooth regulates the forms of the condyle, of the scapula, and of the claws, in the same manner as the equation of a curve regulates all its properties; and as, by taking each property separately for the base of a particular equation, we find both the ordinary equation, and all the other properties whatever; so, the claw, the scapula, the condyle, the femur, and all the other bones taken separately, give the tooth, or are reciprocally given by it; and thus, by commencing with any one of these bones, a person who possesses an accurate knowledge of the laws of organic economy, may reconstruct the whole animal.

This principle seems sufficiently evident, in the general acceptation in which it is here taken, and does not require any fuller demonstration; but when it comes to be applied, there will be found many cases where our theoretical knowledge of the relations of forms will not be sufficient, unless it be supported by observation and experience.

For example, we are well aware, that hoofed animals must all be herbivorous, since they have no means of seizing prey. It is also evident, that, having no other use to make of their fore-legs than to support their body, they do not require a shoulder so vigorously organised as that of carnivorous animals; they have, therefore, no acromion or clavicle, and their shoulder-blades are narrow. Having also no occasion to turn their fore-arm, their radius is united to the ulna by ossification, or at least articulated by a ginglimus or hinge-joint, and not by arthrodia or ball and socket, to the humerus. Their food being herbaceous, will require teeth furnished with flat surfaces, for bruising seeds and plants. The crown of the teeth must also be unequal, and, for this purpose, must be composed of parts alternately consisting of bone and of enamel. Teeth of this structure necessarily require horizontal motions to enable them to triturate the food; and hence the condyle of the jaw cannot be so strictly confined within its articulating cavity as in the carnivorous animals, but must be flattened, and thus correspond with a more or less flattened surface of the temporal bones. Further, the temporal fossa, which will only have a small muscle to contain, will be narrower, and not so shallow, as that of carnivorous animals. All these circumstances are deducible from each other, according to their greater or less generality, and in such a manner, that some of them are essential and exclusively peculiar to hoofed animals, while others, although equally necessary in these animals, are not entirely peculiar to them, but may occur in other animals also, where the rest of the conditions will permit their existence.

If we proceed to consider the orders or subdivisions of the class of hoofed animals, and examine what modifications the general conditions undergo, or rather what particular conditions are conjoined with them, according to the respective characters of these orders, the reasons of these subordinate conditions begin to appear less obvious. We can still easily conceive, in general, the necessity of a more complicated system of digestive organs in those species which have a more imperfect masticatory system; and hence we may presume, that these latter must be rather ruminating animals, in which there is wanting such or such an order of teeth; and may also deduce from the same consideration, the necessity of a certain form of the œsophagus, and of corresponding forms in the vertebræ of the neck, &c. But I doubt whether it would have been discovered, independently of actual observation, that the ruminating animals should all have cloven hoofs, and that they should be the only animals having them; that there should be horns on the fore-head in this class alone; or that such of them as have sharp canine teeth, should, in general, have no horns.

However, since these relations are constant, we may be assured that they have a sufficient cause; but as we are not acquainted with that cause, we must supply the defect of theory by means of observation, and in this way establish empirical laws which become nearly as certain as those deduced from rational principles, when founded upon observations, the authenticity of which is proved by frequent repetition. Hence, at the present day, any one who observes only the print of a cloven foot, may conclude that the animal which left this impression ruminates; and this conclusion is quite as certain as any other in physics, or in moral philosophy. This simple footmark, therefore, indicates at once to the observer the forms of the teeth, of the jaws, of the vertebræ, of all the bones of the legs, thighs, shoulders, and pelvis of the animal which had passed. It is a surer mark than all those of Zadig. That there are secret reasons, however, for all these relations, is what observation alone is sufficient to shew, independently of any general principles of philosophy.

In fact, when we construct a table of these relations, we remark not only a specific constancy, if the expression may be allowed, between a particular form of a particular organ, and some other form of a different organ; but we also perceive a classic constancy of conformation, and a corresponding gradation, in the development of these two organs, which demonstrate their mutual influence, almost as well as the most perfect deduction of reason.

For example, the dentary system of the hoofed animals, which are not ruminant, is in general more perfect than that of the cloven-footed or ruminating animals, because the former have either incisors, or canine teeth, and almost always both in each jaw; and the structure of their foot is in general more complicated, because they have more toes or claws, or their phalanges less enveloped in the hoof,--or a greater number of distinct bones in the metacarpus and metatarsus--or more numerous tarsal bones--or a fibula more distinct from the tibia--or, lastly, that all these circumstances are often united in the same species of animals.

It is impossible to assign reasons for these relations; but we are certain that they are not the effects of chance, because, whenever a cloven-footed animal manifests, in the arrangement of its teeth some tendency to approach the animals we now speak of, it also manifests a similar tendency in the arrangement of its feet. Thus the camels, which have canine teeth, and even two or four incisors in the upper jaw, have an additional bone in the tarsus, because their scaphoid bone is not united to the cuboid, and they have very small hoofs, with corresponding phalanges. The musk animals, whose canine teeth are much developed, have a distinct fibula along the whole length of their tibia; while the other cloven-footed animals have only, in place of a fibula, a small bone articulated at the lower end of the tibia. There is, therefore, a constant harmony between two organs apparently having no connection; and the gradations of their forms preserve an uninterrupted correspondence, even in those cases in which we cannot account for their relations.

Now, by thus adopting the method of observation as a supplementary means, when theory is no longer able to direct our views, we arrive at astonishing results. The smallest articulating surface of bone, or the smallest apophysis, has a determinate character, relative to the class, the order, the genus, and the species to which it belonged; insomuch, that when one possesses merely a well preserved extremity of a bone, he can, by careful examination, and the aid of a tolerable analogical knowledge, and of accurate comparison, determine all these things with as much certainty as if he had the entire animal before him. I have often made trial of this method upon portions of known animals, before reposing full confidence upon it, in regard to fossil remains; and it has always proved so completely satisfactory, that I have no longer any doubts regarding the certainty of the results which it has afforded me.

It is true, that I have enjoyed all the advantages which were necessary for the undertaking; and that my favourable situation, in the Museum of Natural History at Paris, and assiduous research for nearly thirty years, have procured me skeletons of all the genera and sub-genera of quadrupeds, and even of many species in some genera, and of several varieties of some species. With such means, it was easy for me to multiply my comparisons, and to verify in all their details the applications which I have made of the various laws deducible from such circumstances as have been stated.

We cannot here enter into a more lengthened detail of this method, and must refer to the large work on Comparative Anatomy, in which all its rules will be found. In the mean time, an intelligent reader may gather a great number of these from the work upon Fossil Bones, if he take the trouble of attending to all the applications of them which we have there made. He will see, that it is by this method alone that we are guided, and that it has almost always sufficed for referring each bone to its species, when it was a living species--to its genus, when it was an unknown species--to its order, when it was a new genus--and to its class, when it belonged to an order not hitherto established--and to assign it, in the three last cases, the proper characters for distinguishing it from the nearest resembling orders, genera, and species. Before the commencement of our researches, naturalists had done no more than this with regard to animals, which they had the opportunity of examining in their entire state. Yet, in this manner, we have determined and classed the _remains_ of more than a hundred and fifty mammiferous and oviparous quadrupeds.

_View of the General Results of these Researches._

Considered with regard to species, upwards of ninety of these animals are most assuredly hitherto unknown to naturalists; eleven or twelve have so perfect a resemblance to species already known, that the slightest doubt cannot be entertained of their identity; the others exhibit many traits of resemblance to known species, but their comparison has not yet been made with sufficient precision to remove all doubts.

Considered with regard to genera, of the ninety hitherto unknown species, there are nearly sixty that belong to new genera. The other species rank under genera or subgenera already known.

It may not be without use, also, to consider these animals with regard to the classes and orders to which they belong. Of the hundred and fifty species, about a fourth part are oviparous quadrupeds, and all the rest mammifera. Of these last, more than the half belong to non-ruminant hoofed animals.

Notwithstanding what has been done, it would still be premature to establish upon these numbers any conclusion relative to the theory of the earth, because they are not in sufficient proportion to the numbers of genera and species which may be buried in the strata of the earth. Hitherto the bones of the larger species have been chiefly collected, these being more obvious to agricultural labourers; while the bones of the smaller species are usually neglected, unless when they chance to fall into the hands of a naturalist, or when some particular circumstance, such as their excessive abundance in certain places, attracts the attention even of the common people.

_Relations of the Species of Fossil Animals with the Strata in which they are found._

The most important consideration, that which, in fact, is the chief object of all my researches, and which establishes their legitimate connection with the Theory of the Earth, is to ascertain in what strata each species is found, and whether there may be some general laws, relative either to the zoological subdivisions, or to the greater or less resemblance of the species to those of the present day.

The laws which have been recognised with respect to these relations are very distinct and satisfactory.

In the first place, it is clearly ascertained that the oviparous quadrupeds appear much more early than the viviparous; that they are even more abundant, larger, and more varied, in the ancient strata than at the surface of the globe, as it exists at present.

The Ichthyosauri, the Plesiosauri, several species of Tortoise, and several species of Crocodile, are found beneath the chalk, in the deposits commonly called _Jura formations_. The Monitors of Thuringia would be still older, if, according to the Wernerian School, the copper-slate in which they are contained, along with a great variety of fishes supposed to have belonged to fresh-water, is to be placed among the oldest beds of the secondary formations. The enormous crocodiles and the great tortoises of Maestricht, are found in the chalk formation itself; but these are marine animals.

This earliest appearance of fossil bones seems, therefore, already to indicate, that dry lands and fresh waters had existed before the formation of the chalk deposits. But neither at this period, nor while the chalk was forming, nor even long after, have any bones of land-mammifera been encrusted; or, at least, the small number of these, which are alleged to have been found in strata of these dates, forms but a trifling exception.

We begin to find bones of marine mammifera, namely, of lamantins and seals, in the coarse shelly limestone which covers the chalk in the neighbourhood of Paris; but there are still no bones of terrestrial mammifera.

Notwithstanding the most assiduous investigation, I have not been able to discover any distinct trace of this class in any of the deposits preceding those which rest upon the coarse limestone. Certain lignites and molasses do in fact contain them; but I am very doubtful whether these deposits are all, as is commonly supposed, anterior to that limestone. The places where these bones have been found are so limited, both in extent and in number, as to induce us to suppose some irregularity, or some repetition of the formation containing them. On the contrary, the moment we arrive at the deposits which rest upon the coarse limestone, the bones of land-animals present themselves in great abundance.

As it is reasonable to believe that shells and fishes did not exist at the period of the formation of primitive rocks, we are also led to conclude that the oviparous quadrupeds began to exist along with the fishes, and at the commencement of the period during which the secondary rocks were formed; but that the land-quadrupeds did not appear upon the earth, at least in any considerable number, till long after, and until the coarse limestone strata, which contain the greater number of our genera of shells, although of species different from ours, had been deposited.

It is remarkable that those coarse limestone strata which are used at Paris for building, are the last formed strata which indicate a long and quiet continuance of the sea upon our continents. Above them, indeed, there are found formations containing shells and other marine productions; but these consist of collections of transported matters, sand, marls, sandstones, and clays, which rather indicate transportations that have taken place with more or less violence, than strata formed by tranquil deposition; and, if there be some rocky and regular strata of pretty considerable magnitude, beneath or above these transported matters, they generally exhibit indications of having been deposited from fresh water.

Almost all the known bones of viviparous quadrupeds, therefore, have been found either in those fresh-water formations, or in the alluvial formations; and consequently there is every reason to conclude that these quadrupeds have only begun to exist, or, at least, to leave their remains in the strata of our earth, after the last retreat of the sea but one, and during the state of things that preceded its last irruption.

But there is also an order in the disposition of these bones with regard to each other; and this order further announces a very remarkable succession in the appearance of the different species. All the genera which are now unknown, the Palæotheria, Anaplotheria, &c., with the position of which we are thoroughly acquainted, belong to the oldest of the formations of which we are now speaking, those which rest immediately upon the coarse limestone. It is chiefly these genera which occupy the regular beds that have been deposited from fresh-water, or certain alluvial beds of very ancient formation, generally composed of sand and rolled pebbles, and which were perhaps the earliest alluvium of that ancient world. Along with these there are also found some lost species of known genera, but in small numbers, and some oviparous quadrupeds and fishes, which appear to have been all inhabitants of fresh-water. The beds which contain them are always more or less covered by alluvial beds, containing shells, and other marine productions.

The most celebrated of the unknown species, which belong to known genera, or to genera closely allied to those which are known, such as the fossil elephants, rhinoceroses, hippopotami, and mastodons, do not occur along with those more ancient genera. It is in the alluvial formations alone that they are discovered, sometimes accompanied with marine shells, and sometimes with fresh-water shells, but never in regular stony beds. Every thing that is found along with these species is either unknown like themselves, or at least doubtful.

Lastly, the bones of species which are apparently the same as those that are still found alive, are never discovered, except in the last alluvial deposits formed on the sides of rivers, or on the bottoms of ancient pools or marshes now dried up, or in the substance of beds of peat, or in the fissures and caverns of some rocks; or, lastly, at small depths below the surface, in places where they may have been buried by the falling down of debris, or even by the hand of man; and their superficial position renders these bones, although the most recent of all, almost always the worst preserved.

It must not, however, be thought that this classification of the various geological positions of fossil remains, is as certain as that of the species, or that it is equally capable of demonstration. There are numerous reasons which prevent this from being the case.

In the first place, all my determinations of species have been made upon the bones themselves, or by means of good figures; whereas it has been impossible for me personally to examine all the places in which these bones have been discovered. I have very frequently been obliged to content myself with vague and ambiguous accounts, given by people who were not themselves well aware of what it was necessary to observe; and, more frequently still, I have been unable to procure any information whatever on the subject.

Secondly, these repositories of organic remains are subject to infinitely greater doubts, than the bones themselves. The same formation may appear recent in places where it shews itself at the surface, and ancient in those where it is covered by the beds which have succeeded it. Ancient formations may have been transported by partial inundations, and thus have covered recent bones; they may have fallen upon them by crumbling, and thus have enveloped and mingled them with the productions of the ancient sea, which they previously contained. Bones of ancient periods may have been washed out by the waters, and afterwards enveloped in recent alluvial formations. Lastly, recent bones may have fallen into the fissures or caverns of ancient rocks, and been enveloped by stalactites or other incrustations. In every individual instance, therefore, it becomes necessary to analyze and appreciate all those circumstances which might disguise the real origin of fossil remains; and it rarely happens that people who have collected bones have been themselves aware of this necessity, the consequence of which has been, that the true characters of their geological position have been almost always neglected or misunderstood.

Thirdly, there are some doubtful species, which must occasion more or less uncertainty in the results of our researches, until they have been clearly ascertained. Thus the horses and buffaloes that occur along with the elephants, have not yet received appropriate specific characters; and such geologists as are disinclined to adopt the different epochs which I have endeavoured to establish with regard to fossil bones, may, for many years to come, draw from thence an argument against my system, so much the more convenient as it is contained in my own work.

But allowing that these epochs are liable to some objections, from such as may only consider some particular case, I am not the less satisfied, that those who shall take a comprehensive view of the phenomena, will not be checked by such inconsiderable and partial difficulties, and will be led to conclude, as I have done, that there has been at least one, and very probably two, successions in the class of quadrupeds, previous to that which at the present day peoples the surface of the earth.

_Proofs that the Extinct Species of Quadrupeds are not varieties of the presently existing Species._

I now proceed to the consideration of another objection, one, in fact, which has already been urged against me.

Why may not the presently existing races of land quadrupeds, it has been asked, be modifications of those ancient races which we find in a fossil state; which modifications may have been produced by local circumstances and change of climate; and carried to the extreme difference which they now present, during a long succession of ages?

This objection must appear strong to those especially who believe in the possibility of indefinite alteration of forms in organised bodies; and who think that, during a succession of ages, and by repeated changes of habitudes, all the species might be changed into one another, or might result from a single species.

Yet to these persons an answer may be given from their own system. If the species have changed by degrees, we ought to find traces of these gradual modifications. Thus, between the palæotheria and our present species, we should be able to discover some intermediate forms; and yet no such discovery has ever been made.

Why have not the bowels of the earth preserved the monuments of so strange a genealogy, if it be not because the species of former times were as constant as ours; or, at least, because the catastrophe which destroyed them, had not left them sufficient time for undergoing the variation alleged?

In order to reply to those naturalists who acknowledge that the _varieties_ of animals are restrained within certain limits fixed by nature, it would be necessary to examine how far these limits extend. This is a very curious inquiry,--highly interesting in itself, under a variety of relations, and yet one that has been hitherto very little attended to.

Before entering upon this inquiry, it is proper to define what is meant by a _species_, so that the definition may serve to regulate the employment of the term. A species, therefore, may be defined, as comprehending _the individuals which descend from each other, or from common parents, and those which resemble them as much as they resemble each other_. Thus, we consider as _varieties_ of a species, only the races more or less different which may have sprung from it by generation. Our observations, therefore, regarding the differences between the ancestors and descendants, afford us the only certain rule by which we can judge on this subject; all other considerations leading to hypothetical conclusions destitute of proof. Now, considering the _varieties_ in this view, we observe that the differences which constitute it, depend upon determinate circumstances, and that their extent increases in proportion to the intensity of these circumstances.

Thus, the most superficial characters are the most variable: the colour depends much upon the light; the thickness of the fur upon the heat; the size, upon the abundance of food. But in a wild animal, even these varieties are greatly limited by the natural habits of the animal itself, which does not voluntarily remove far from the places where it finds, in the necessary degree, all that is requisite, for the support of its species, and does not even extend its haunts to any great distance, unless it also finds all these circumstances conjoined. Thus, although the wolf and the fox inhabit all the climates from the torrid to the frigid zone, we hardly find any other difference among them, in the whole of that vast space, than a little more or a little less beauty in their fur. I have compared skulls of foxes from the northern countries and from Egypt, with those of the foxes of France, and have found no difference but such as might be expected in different individuals. Such of the wild animals as are confined within narrower limits, vary still less, especially those which are carnivorous. The only difference between the hyena of Persia and that of Morocco, consists in a thicker or a thinner mane.

The wild herbivorous animals feel the influence of climate somewhat more extensively, because there is added to it in their case, the influence of the food, which may happen to differ both as to quantity and quality. Thus, the elephants of one forest are often larger than those of another; and their tusks are somewhat longer in places where their food may happen to be more favourable for the production of the matter of ivory. The same may take place with regard to the horns of rein-deer and stags. But let us compare two elephants the most dissimilar, and we shall not discover the slightest difference in the number and articulations of the bones, the structure of the teeth, &c.

Besides, the herbivorous species, in the wild state, seem more restrained from dispersing than the carnivorous animals, because the sort of food which they require, combines with the temperature to prevent them.

Nature also takes care to guard against the alteration of the species, which might result from their mixture, by the mutual aversion with which it has inspired them. It requires all the ingenuity and all the power of man to accomplish these unions, even between species that have the nearest resemblances. And, when the individuals produced by these forced conjunctions are fruitful, which is very seldom the case, their fecundity does not continue beyond a few generations; and would not probably proceed so far, without a continuance of the same cares which excited it at first. Thus, we never see in our woods individuals intermediate between the hare and the rabbit; between the stag and the doe; or between the martin and the pole-cat.

But the power of man changes this order; it discloses all those variations, of which the type of each species is susceptible; and from them derives productions which the species, if left to themselves, would never have yielded.

Here the degree of the variations is still proportional to the intensity of their cause, which is slavery. It is not very high in the semi-domesticated species, such as the cat. A softer fur; more brilliant colours; greater or less size; these form the whole extent of the variations in this species; for the skeleton of an Angora cat differs in no regular and constant circumstance from that of a wild cat.

In the domesticated herbivorous animals, which we transport into all kinds of climates, and subject to all kinds of management, both with regard to labour and nourishment, we certainly obtain greater variations; but still they are all merely superficial. Greater or less size; longer or shorter horns, or even the want of these entirely; a hump of fat, larger or smaller, on the shoulder; these form the differences between the various races of the common ox or bull; and these differences continue long, even in such breeds as have been transported from the countries in which they were produced, when proper care is taken to prevent crossing.

Of this nature are also the innumerable varieties of the common sheep, which consist chiefly in differences of their fleeces, as the wool which they produce is an important object of attention. These varieties, although not quite so perceptible, are yet sufficiently marked among horses. In general, the forms of the bones vary little; their connections and articulations, and the forms of the large grinding teeth, never vary at all.

The small size of the tusks in the domestic hog, compared with the wild boar’s, and the junction of its cloven hoofs into one in some races, form the extreme point of the differences which we have produced in the domesticated herbivorous quadrupeds.

The most remarkable effects of the influence of man are manifested in the animal which he has reduced most completely under subjection, the dog,--that species so entirely devoted to ours, that even the individuals of it seem to have sacrificed to us their will, their interest, and inclination. Transported by man into every part of the world, subjected to all the causes capable of influencing their development, regulated in their sexual intercourse by the pleasure of their masters, dogs vary in colour; in the quantity of their hair, which they sometimes even lose altogether, and in its nature; in size, which varies as one to five in the linear dimensions, amounting to more than a hundred fold in bulk; in the form of the ears, nose, and tail; in the proportional length of the legs; in the progressive development of the brain in the domestic varieties, whence results the form of their head, which is sometimes slender, with a lengthened muzzle and flat forehead, and sometimes having a short muzzle and a protuberant forehead; insomuch that the apparent differences between a mastiff and a water-spaniel, and between a greyhound and a pug, are more striking than those that exist between any two species of the same natural genus in a wild state. Finally, and this may be considered as the maximum of variation hitherto known in the animal kingdom, there are races of dogs which have an additional toe on the hind foot, with corresponding tarsal bones; as there are, in the human species, some families that have six fingers on each hand. Yet, in all these varieties, the relations of the bones remain the same, nor does the form of the teeth ever change in any perceptible degree; the only variation in respect to these latter being, that, in some individuals, one additional false grinder appears, sometimes on the one side, and sometimes on the other[82].

Animals, therefore, have natural characters, which resist every kind of influence, whether natural or produced by human interference, and nothing indicates that, with regard to them, time has more effect than climate and domestication.

I am aware that some naturalists lay great stress upon the thousands of ages which they call into action by a dash of the pen; but, in such matters, we can only judge of what a long period of time might produce, by multiplying in idea what a less time produces. With this view, I have endeavoured to collect the most ancient documents relating to the forms of animals; and there are none which equal, either in antiquity or abundance, those that Egypt furnishes. It affords us, not only representations of animals, but even their identical bodies embalmed in its catacombs.

I have examined with the greatest attention the figures of quadrupeds and birds sculptured upon the numerous obelisks brought from Egypt to ancient Rome. All these figures possess, in their general character, which alone could be the object of attention to an artist, a perfect resemblance to the species represented, such as we see them at the present day.

On examining the copies made by Kirker and Zoega, we find that, without preserving every trait of the originals in its perfect purity, they have given figures which are easily recognised. We readily distinguish the ibis, the vulture, the owl, the falcon, the Egyptian goose, the lapwing, the landrail, the aspic, the cerastes, the Egyptian hare with its long ears, and even the hippopotamus; and, among the numerous monuments engraved in the great work on Egypt, we sometimes observe the rarest animals, the algazel, for example, which was not seen in Europe until within these few years[83].

My learned colleague, M. Geoffroy Saint-Hilaire, strongly convinced of the importance of this research, carefully collected in the tombs and temples of Upper and Lower Egypt as many mummies of animals as he could. He has brought home cats, ibises, birds of prey, dogs, monkeys, crocodiles, and the head of an ox, in this state; and there is certainly no more difference to be perceived between these mummies and the species of the same kind now alive, than between the human mummies and the skeletons of men of the present day. A difference may, indeed, be found between the mummies of the ibis and the bird which naturalists have hitherto described under that name; but I have cleared up all doubts on this matter, in a Memoir upon the Ibis, which will be found at the end of this Essay, and in which I have shewn that it is still at the present day the same as it was in the time of the Pharaohs. I am aware that, in these, I only cite the monuments of two or three thousand years; but this is the most remote antiquity to which we can resort in such a case.

There is nothing, therefore, to be derived from all the facts hitherto known, that could, in the slightest degree, give support to the opinion that the new genera which I have discovered or established among the fossil remains of animals, any more than those which have in like manner been discovered or established by other naturalists, the _palæotheria_, _anoplotheria_, _megalonyces_, _mastodonta_, _pterodactyli_, _ichthyosauri_, &c. might have been the sources of the present race of animals, which have only differed from them through the influence of time or climate. Even if it should prove true, which I am far from believing to be the case, that the fossil elephants, rhinoceroses, elks, and bears, differ no more from those at present existing, than the present races of dogs differ from one another, this would not furnish a sufficient reason for inferring the general identity of the species, because the races of dogs have been subjected to the influence of domestication, which these other animals neither did nor could experience.

Farther, when I maintain that the rocky beds contain the bones of several genera, and the alluvial strata those of several species which no longer exist, I do not assert that a new creation was required for producing the species existing at the present day. I only say that they did not originally inhabit the places where we find them at present, and that they must have come from some other part of the globe.

Let us suppose, for instance, that a great irruption of the sea were now to cover the continent of New Holland with a coat of sand or other debris; it would bury the carcases of animals belonging to the genera _Kangurus_, _Phascolomys_, _Dasyurus_, _Perameles_, flying phalanger, echidna, and ornithorynchus, and it would entirely destroy the species of all these genera, since none of them exist now in any other country.

Were the same revolution to lay dry the numerous narrow straits which separate New Holland from the continent of Asia, it would open a road to the elephants, rhinoceroses, buffaloes, horses, camels, and tigers, and to all the other Asiatic quadrupeds, which would come to people a land where they had been previously unknown.

Were some future naturalist, after having made himself well acquainted with this new race of animals, to search below the surface on which they live, he would find remains of quite a different nature.

What New Holland would be, under the circumstances which we have supposed, Europe, Siberia, and a large portion of America, now actually are. And, perhaps, when other countries shall have been examined, and New Holland among the rest, it will one day be found that they have experienced similar revolutions, I might almost say, mutual changes, of productions. For, if we push the supposition farther, and, after the supply of Asiatic animals to New Holland, admit a second revolution, which destroyed Asia, their original country, those naturalists who might observe them in New Holland, their second country, would be equally at a loss to know whence they had come, as we now are to find out the origin of the races of animals that inhabit our own countries.

I now proceed to apply this manner of reasoning to the human species.

_Proofs that there are no Fossil Human Bones._

It is certain that no human bones have yet been found among fossil remains; and this furnishes an additional proof that the fossil races were not mere varieties of known species, since they could not have been subjected to human influence.