All these creatures live on vegetables, with the exception of the hog, to whom nothing comes amiss; or who, in other words, is omnivorous, like the bear, and also another member of the class Mammalia, which I do not name for fear of making you blush at your companionship. This assures you that, in the order of the Pachydermata, the digestive apparatus is very fully developed. The horse, for instance, has a very voluminous stomach, which extends much farther back than the point at which the oesophagus empties itself; and in which, on close examination, a sort of contraction is observed which appears to divide it in half, producing the false effect of there being two stomachs. But, after all, we do not find, even in this case, any essential difference to remark upon in the internal arrangements; it is always the teeth we must look at if we want to have something to say. There, indeed, we have only to choose; nature has indulged herself in all manner of fantastic freaks.

To begin with the elephant, the grand master of the order, he presents us with one of the most oddly-furnished jaws in existence. Every one knows those two enormous tusks which protrude from his mouth, and which furnish human industry with nearly the whole store of ivory it has need of. Those two teeth are the largest, beyond comparison, of any in the animal kingdom; yet they are two merely ornamental teeth, perfectly useless in the operation of eating, and very ruinous into the bargain to the proprietor. All those stores of the blood which furnish the materials for ivory pass into these tusks, and, as often happens to people who give way to a taste for luxuries, there is nothing left wherewith to provide the animal with serviceable teeth. Those tusks of the elephant are nothing but his upper incisors, the only ones, observe, which curve in coming out of his jaw. In the lower jaw he has no incisors at all; canine teeth are entirely wanting; and by way of dental apparatus, this meagerly-furnished mouth possesses on each side of either jaw one or two molars, enormous in size, but not of ivory. They are composed of a number of enamelled upright layers of tooth-substance (dentine), soldered together with a bony cement; and these are our giant's only resource for chewing the grass, young shoots, and leaves of trees, which are his natural food. [Footnote: These teeth are nevertheless very efficient grindstones.] As a consolation, he has the glory of knowing that he possesses the very finest teeth in the world, the terror of all who approach him; and I can compare him to nothing so well as to a vain woman, who is contented to live on potatoes that she may wear fine clothes and excite the envy of her neighbors.

The hippopotamus also has incisors in the upper jaw, which curve as they come out of the mouth; but these never attain anything like the size of the elephant's tusks, neither do they hinder the development of the other teeth, of which this animal has a very respectable collection. The upper incisors bend downward; those in the lower jaw stand out horizontally, and terminate in sharp points like plough-shares; and indeed the hippopotamus uses them for tearing up the ground in order to get at the roots which form its nutriment. These are, besides, formidable weapons, with which when enraged the animal can tear even boats in pieces; for, as you are aware, the hippopotamus is almost amphibious, and browses on water-plants, and lives in the great rivers of Africa, its native country. Its name alone would have told you this had you understood Greek; [Footnote: Ippos, a horse, and potamos, a river. The Greeks, who had seen the hippopotamus in the Nile, in Egypt, named it the river-horse; as afterwards the Romans called the elephant the ox of Lucania, because they first saw it in Lucania during the war with Pyrrhus.] but I have no complaint to make this time, for it was the Greeks themselves who gave it. You would find it very awkward, would you not? if you had to breakfast at the bottom of the Thames, and could not swallow a morsel without having your nose filled with water? But the hippopotamus labors under no such inconvenience. Its nostrils are provided with two little doors, which it closes at will, and behind this screen the lungs keep quite quiet while the animal goes backwards and forwards in the water. There is generally a hippopotamus in every large menagerie. The next time you visit one look at him. You will see him with a large stomach almost trailing on the ground: and no wonder; he needs plenty of room in which to stow away all the canes, reeds, and water-plants from the bottoms of rivers, which are not very nutritious food. Accordingly the stomach of the river-horse presents the appearance not only of two compartments, like that of the true horse, but looks as if it were divided into three or four.

To conclude my account of this animal, I must add that the ivory of its teeth is even more beautiful than that of the elephant's tusks, and that dentists carve it into very magnificent teeth for their patients. This is not a matter to interest you much at present, but we never know what may happen. I advise you, however, never to make use of hippopotamus's teeth; they turn yellow very quickly, and, when people are driven to buy teeth, the least they can try for, is to get good-looking ones for their money.

I should like to say something about the rhinoceros while we are on the colossal tribes, but it is a very unsatisfactory subject. The animal has no canines, sometimes no incisors even; sometimes it has as many as thirty-six teeth, according to the species, as naturalists aver; and this is all I have to say about this great lump of flesh, so misshapen outside, yet so regularly formed within. He it is who especially deserves the title pachydermata, his skin being so hard and thick that bullets glance off its surface. But this has nothing to do with our present subject, any more than the horn upon his nose, whose turn for description may come if I ever give you the history of the skin and all connected with it.

The hog also has canines, and very strong ones; but it is in the wild state, when it is called a boar, that these appear in their real form. There we find them projecting out of the mouth with a curve, as is so commonly seen among the pachydermata, forming those terrible, sharp, and pointed tusks which have been so often fatal to the hunter. The wild boar of the forest is supposed to be the original ancestor of the domestic pig; and if, as is probable, this is really the case, we have here a remarkable instance of the effect of man's treatment upon the organisation of the animals he collects around him. The wild boar lives only on fruits and roots, which, like the hippopotamus, he tears up with his tusks, those safeguards of his, amid the many perils of his life in the woods. In the service of man, on the contrary, he becomes lazy, cowardly, and greedy; unlearns his energy and combativeness, eats all that is offered to him in the trough, even meat, when it happens to be thrown in; and, in order to do this moreeasily, has recalled toward his mouth those formidable war-tusks of his, so tremendous as weapons, so useless as teeth; has, in fact, turned his sword into a fork. It is the case of a Tartar degenerated into a Chinaman. [Footnote: China, about which we have heard a great deal of late years, has been several times invaded by the warrior hordes of Tartary. But at each time, unto the second and third generations, the vanquishers have taken the effeminate manners, the costume and the usages of the vanquished, and so many conquests have only resulted in converting millions of Tartars into Chinese.]

This suggests to me an idea relative to the horse, the last important member of the pachydermata which remains to be spoken of. It also has its canines, but very small ones; they disappear, so to speak, in a large vacancy between the incisors and the molars, where man inserts the bit, by means of which the animal has been subdued. Small as these are, however, these canines indicate that the horse might eat flesh, canine teeth being the distinctive attribute of the carnivorous mammals. I have read somewhere, but I do not remember where, that an unusual development of strength could be produced in the horse by feeding it on flesh; and the old Greek poets write of a king [Footnote: Diomed, King of Thrace] in the barbarous ages who gave his horses, men for food. If I knew some rich professor who was inclined to spend money in the investigation of a curious fact, I would advise him to set apart a sum for putting horses on a meat diet, from sire to son, gradually increasing the quantity; and I would boldly warrant that in the course of successive generations the canines would become so large as to impede the entrance of the bit into the mouth, and, moreover, would make it rather a ticklish office for the groom to place it there. But let us set aside the teeth the horse might possibly have, in order to examine those it has already. There are six incisors in each jaw; these are long and rather projecting teeth, by examining which, the age of the horse can be detected from certain marks which appear in them from year to year. The molars are flat, square, furrowed with bars of enamel, marking out more or less distinct crescents; perfectly constructed, in short, for chewing hay and oats. Nevertheless, I should never be surprised to see the enamel crescents become sharp-cutting in our rich professor's stable; so skillful is the unseen Architect who created animals, in altering the house when the tenant changes his habits.

ORDER 8. Ruminantia (ruminants).

I shall retain through life a pleasant recollection of the ruminants. Through them I obtained the first prize for natural history which was ever given in France to the pupils of the learned university. It is thirty years ago since this happened, and I own, without any false modesty, that even now the word ruminant rings very agreeably in my ear. It reminds me of one of the proudest moments of my life, of the honor done to me by the illustrious Geoffroy St. Hilaire, when he called me, a little college urchin, up to him, that he might have a nearer view, as he said, of the baby-professor who had spoken so well on ruminants. Yes, it is more than thirty years ago, for alas! it was in 1831. There needed no less an event, as I have told you before, than the revolution of 1830 in France to induce the big-wigs of education to sacrifice two hours per week in one class to the study of natural history. Yes, my dear child, it is only that short time ago since natural history became one of the subjects of study in French colleges; and the gray-haired men of the present day finished their education, as it is called, without having learnt a single word of what I am now taking the trouble to teach you, a mere child. You see you have come into the world just at the right time, and will be able to instruct others in your turn. But before giving lessons to other people you must first finish learning your own. Forgive me this involuntary reference to a happy time when I was not much more rational than you are. And now, let us return to our ruminants—those dear, good beasts, the nourishing fathers of the human race.

LETTER XXXII.