Elephant tooth

“ I shall only observe here, that in the jaw of this animal, like those of all others of a carnivorous nature, the roots or fangs are inserted into the mass of bone, which not only surrounds the roots, but divides one tooth from the other; whereas in the elephant the grinders occupy one large and uniform cavity, from which they are gradually protruded as they are required for the purpose of grinding. ”

“ The scalpriform incisors of the rodents, already alluded to, have the enamel band on the front face of the tooth; the softer dentine behind wears away more rapidly, keeping the cutting surface bevelled, like the edge of a chisel, while the hard enamel forms the sharp edge. In some instances the enamel is absent altogether and the teeth are composed entirely of dentine, as in the elephant tusk. ”

“ A thick pad of fat, etc., makes the animal when alive look as if plantigrade, whereas it is, as a matter of fact, digitigrade. In internal features the most prominent difference from E. indicus is in the molar teeth, which are ridged by much fewer ridges. The outside number for a single tooth in the present species is 10 or 11. In Elephas indicus on the other hand there are as many as 27.
The African Elephant, thinks Sir Samuel Baker, reaches a height of about 12 feet, and it will be remembered that the notorious "Jumbo" was found to be 11 feet high at the shoulder. ”

“ South Bloomfield, Pickaway County.—In the article just cited, Hildreth told of securing, near South Bloomfield, teeth of the “American elephant,” in association with those of the mastodon. They were found in excavating for a culvert over a small branch near the town. Hildreth described the teeth, so that it is certain that they belonged to an elephant; but the species can not be determined. A tooth is described as being 7 inches broad, 6 inches long, and 3 inches thick. ”

“ No lady could very well be suspected of carrying off in her muff an elephant's tooth of some hundred weight, but there must have been female thieves, dexterous enough to secrete, perhaps a rhinoceros's tooth, of perhaps some dozen pounds, valued at one pound seven shillings per pound ”

“ As the tooth wears in its work, the enamel comes to project above the surface of the tooth, and a characteristic pattern is thus developed on the surface of the molars of each species of living elephant. ”

“ Fig. 252.—Molar tooth of Elephas antiquus, one-third of the natural size. Pliocene and Post-Pliocene. it survived to an even later stage of the Post-Pliocene period. The molar teeth are of the type of the existing Indian Elephant, with comparatively thin enamel-ridges, placed closer together than in the African type; whilst the tusks were nearly straight.
Amongst the Pliocene Carnivores, we meet with true Bears (Ursus Arvernensis) , Hyænas (such as Hyœna Hipparionum) , and genuine Lions (such as the Felis angustus of North America) ”

“ Nevertheless, the writer regards the tooth as belonging to E. primigenius. It is unusually long for the species; hence the plates are thicker, quite as thick as some specimens of E. columbi. However, the enamel, as shown on the worn face, is much thinner than that of E. columbi and comparatively little folded. The plates are only moderately concave on the hinder face. The height of the tooth at the ninth plate is 140 mm.
6. Lewiston, Niagara County.—From Mr. C. A. Hartnagel the writer received information of the finding of a tooth of an elephant at Lewiston ”

“ Thus, in the Indian elephant, the molars exhibit a series of cross-ridges, which are more numerous than those of the African species, while in the latter form the enamel plates form a distinctly lozenge-shaped pattern. It sometimes happens that in elephants kept in captivity the succession of the teeth is disarranged, from the fact that the molars are not worn away fast enough, and the succeeding teeth are displaced, thereby causing deformity of the jaws. ”

“ The teeth are the chief points of distinction between the elephant and the mastodon; and they are readily recognized by the grinding surfaces of the molars, which have transverse ridges, their summits being divided into conical cusps, with smaller ones often clustered about them. [60] The enamel is quite thick: the cementum, which is so plentiful in the teeth of elephants, is very scanty, never filling in the interspaces of the ridges ”

“ 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. ”

“ This skull would be far too heavy to carry if it were not full of hollows, making a large framework to bear the tusks of smooth white ivory, which grow out from the upper jaw to a length of more than six feet on each side,172 and weigh sometimes from eighty to one hundred pounds. Surely a wonderful size for teeth, and we shall not wonder that they are the only front teeth that the elephant has, and that they go on growing all his life from a permanent pulp, like the gnawing teeth of the rodents. ”

“ The molar teeth, of which there are five on each side of the upper jaw, and four in the lower, are hollow prismatic cylinders, straight, seven to nine inches long, and implanted in deep sockets. There are no other teeth, but these are composed of different substances, and so arranged that, as the tooth wears, the surface always presents a pair of transverse ridges, thus producing a dental apparatus well suited for grinding up vegetable food. In the elephants, which live on similar food, the grinding is effected by great molar teeth, which are replaced by new ones as the old ones are worn away. ”

“ The Elephant has, from first to last, six, or perhaps eight, molars on each side of each jaw; but there are never more than two partially, or one wholly, in use at once. They have originally an uneven surface, produced by the extremities of a number of what may be considered as so many finger-like constituent teeth, arranged in transverse rows, covered by hard enamel, and cemented together by a bony substance. ”

“ These teeth, when worn out, are succeeded by others pushing forward from behind, and not forced up vertically, as in the case of ordinary deciduous teeth, so that it occasionally happens that the elephant has sometimes one and sometimes two grinders on each side, according to age. In the wild state sand and grit, entangled in the roots of plants, help in the work of attrition, and, according to Professor W. Boyd Dawkins, the tame animal, getting cleaner food, and not having such wear and tear of teeth, gets a deformity by the piling over of the plates of which the grinder is composed. ”

“ The molar teeth of the former animal are, too, of much coarser construction, with fewer and larger plates and thicker enamel than in the latter, which would naturally lead one to suppose that the African elephant is accustomed to eat coarser, harder food than the Asiatic species. ”

“ From the end of the second to the beginning of the sixth year, the third set come gradually forward as the jaw lengthens, not only to fill up this additional space, but also to supply the place of this second set, which are, during the same period, gradually worn away, and have their fangs absorbed. From the beginning of the sixth to the end of the ninth year, the fourth set of grinders come forward to supply the gradual waste of the third set. In this manner to the end of life, the Elephant obtains a set of new teeth, as the old ones become unfit for the mastication of its food. ”

“ The elephant (see Fig. 9) has no sign of the six little front teeth (incisors) above and below which we find in the typical dentition and in many living mammals, nor of the corner teeth (dog-teeth, or canines) . In the upper jaw in front there is the one huge tusk on each [Pg 86] side, and in the lower jaw no front teeth at all! Then as to the grinders. In the elephant these are enormous, with many transverse ridges on the elongated crown, and so big that there is only room for one at a time in each half of upper and lower jaw. ”

“ The teeth resemble the teeth of the rhinoceros as to bulk and general appearance, and, consisting as they do of incisors and molars, were recognized to belong to the order of herbivorous quadrupeds. The thigh-bone exceeds that of the largest-sized elephant, being from four to five feet in height, and presenting a circumference of nearly two feet in its smallest part. ”

“ I believe it has been well enough ascertained that the teeth of this animal are perfectly carnivorous, as they have every quality of form and substance that is required: the roots are not in such a massy body as the elephant’s, and the teeth are composed of a bony substance projecting into strong obtuse points to form the grinding surface, and all this surface encrusted with a strong coat of enamel; whereas all graminivorous animals have teeth whose grinding surface is flat, and composed of an intermixture of bone and enamel ”

“ At the same time the probabilities are in favour of its being true. Cuvier committed himself to the statement that the tusks of the elephant have no attachments to connect them with the pulp lodged in the cavity at their base, from which the peculiar modification of dentine, known as “ivory” is secreted;162 and hence, by inference, that they would be devoid of sensation. ”

“ The enamel is derived from the outer layer of the embryonic dog-fish, the epiblast, which also gives rise to the epidermis; while the dentine and bony base arise in the underlying mesoblast, the dermis. A mammalian tooth has essentially the same structure: an outer coat of enamel, derived from epiblast, overlies a mass of dentine, resting on bone, but the dentine is excavated internally, to form a pulpcavity containing blood-vessels and nerves. Most land animals, however, have teeth only in their mouths, and have lost altogether the external teeth which constitute the armour of the dog-fish. ”

“ Their length in the jaw is great, to insure solidity without actual union with the bone. The loss of an incisor results in the abnormal lengthening of the opposing one, which may finally interfere with mastication and cause starvation. Ruminants have no incisors in the upper jaw; the elephant has none in the lower jaw, but the tusks are upper incisors. ”

“ The teeth of elephants are remarkable; for they [Pg 274] consist of only one large grinder on each side, and in each jaw, which looks like a bundle of smaller teeth, fastened together by intervening and surrounding plates of enamel. These grinders change frequently during the life of the animal, perhaps even six or eight times, as long as the jaw grows; and the new arrivals do not come from below, but are formed behind the old one, and push it out. ”

“ This is most obvious when the prepared bony skull and lower jaw are examined, but can be sufficiently clearly seen in the living animal. The lower jaw and the part of the upper jaw against which it and its grinders play is extraordinarily short and small. The elephant has, in fact, no projecting bony jaw at all, no bony snout, its chin does not project more than that of an old man, and even the part of the upper jaw into which its great tusks are set does not bend forward far from the perpendicular (Fig. 9) . ”

“ With insects the sting supplies the place of teeth; the ape has teeth just like those in man.231 The elephant 59has in the interior of the mouth fourteen teeth, adapted for chewing, in addition to those which protrude; in the male these are curved inwards, but in the female they are straight, and project outwards. The sea-mouse,232 a fish which goes before the balæna, has no teeth at all, but in place of them, the interior of the mouth is lined with bristles, as well as the tongue and palate. Among the smaller land quadrupeds, the two fore-teeth in each jaw are the longest. ”

“ Instead of those long ivory tusks, which form the weapons of the elephant, the rhinoceros has a powerful horn, and two strong incisive teeth in each jaw: these teeth, which the elephant has not, are placed at a great distance, one in each corner or angle of the jaws ”

“ The tusks, which are often lacking in Asiatic Elephants, especially in the females, are the incisors of the upper jaw, grown straight out, and serve primarily as weapons, although in domesticated animals they are used to dig and lift and to carry heavy burdens. Besides these teeth the Elephant has four large molars, two in each jaw, and he is able to chew from four to eight hundred pounds of green fodder a day with them. ”

“ Between the grinders and incisors are toothless gaps. The formation and growth of the teeth are peculiar; and it is strange that the gigantic elephant should be the nearest approach to these small creatures in this respect. The teeth—in most cases the grinders, but always the incisors—grow continuously from a persistent pulp, and therefore loss from attrition is kept constantly supplied by growth from behind. The incisors are planted in a socket which is the segment of a circle. ”

“ It was until very recently believed that the Asiatic elephant yielded the largest teeth, and those imported from Pegu, Cochin-China, and Ceylon, sometimes weighed 150 lbs. Specimens, however, have been obtained from the interior of Africa of much greater weight and dimensions. ”