The females have relatively large tusks, which are essential in obtaining their food.
The latter are dug up with the tusks; the left one being generally employed in this service, and thus becoming much more worn than its fellow.
In the former the upper tusks are bent down so as to cross the tips of the short and chisel-like lower pair.
It is hunted chiefly for the sake of the ivory of its immense tusks, of which it yields the principal source of supply to the European market, and the desire to obtain which is rapidly leading to the extermination of the species.
Mastodons, like elephants, always have a pair of upper tusks, while the earlier ones likewise have a short pair in the lower jaw, which is prolonged into a snout-like symphysis for their support.
It should be added that some of these large tusks came from Ceylon; such tuskers being believed to be descended from mainland animals imported into the island.
The tusks or canines are strongly developed, with FIG.
Occasionally both left and right tusks are developed, in which case the direction of the grooves is the same in both.
The entire tusks are sometimes used for decorative purposes, and are of considerable, though fluctuating, value.
The head is rounded and short, without prominent beetling ridges above the eyes, or a strong crest along the middle line of the back of the skull; and the tusks of the old males are of no very great length and prominence.
In old males the eyes are overhung by a beetling penthouse of bone, the hinder half of the middle line of the skull bears a wall-like bony ridge for the attachment of the powerful jaw-muscles, and the tusks, or canines, are of monstrous size, recalling those of a carnivorous animal.
The African species use the nasal horns as weapons, with which they strike and toss their assailant, but the Asiatic rhinoceroses employ their sharp lower tusks much as does a boar.
The skin is thrown into folds, but these are not strongly marked, and lower tusks are present.
Other modifications are the loss of the upper incisors; the development of the canines into projecting tusks; and the loss of the anterior premolars.
Among still other causes are great bulk, which proves fatal under certain new conditions; relatively slow breeding; extreme specialization and development of dominant organs, such as horns and tusks, on which for a time selection centres to the detriment of more useful characters.
These are regarded as representing a distinct family, the Saghatheriidae, characterized by the possession of the full series of twenty-two teeth in the upper jaw, among which the first pair of incisors was modified to form trihedral rootless tusks, while the two remaining pairs were separated from one another and from the teeth in front by gaps.
From those of all Old World swine or Suinae, the upper canines, or tusks, differ in having their points directed downwards, not outwards or The Collared Peccary (Dicotyles tajacu).
Of the extinct North American peccaries, the typical Dicotyles occur in the Pliocene while the Miocene Bothriolabis, which has tusks of the peccary type, approximates in the structure of its cheek-teeth to the European Miocene genus among the Suinae.
The molars, and more especially the last, are smaller and simpler than in the pigs of the genus Sus, but the peculiarity of this genus is the extraordinary development of the canines, or tusks, of the male.
I should be inclined to believe rather that these tusks were once useful, and were then worn Old Male Babirusa (Babirusa alfurus).
On this latter view we may regard the tusks of the male babirusa as examples of redundant development, analogous to that of the single pair of lower teeth in some of the beaked whales.
Tusks with carved heads (Plate I.
With them were found many reliefs in ivory, on tusks, wands and cylinders.
High, "some like gigantic tusks, some like sugar-loaves, and some like vast stalagmites," but all consisting of iron-grey or reddishbrown conglomerate of gneiss, mica-slate, syenite and greenstone.
Wild oxen of the Sunda race, not to be in any way confounded with the Malayan seladang or gaur, are rare, but the whole country swarms with wild swine, and the babirusa, a pig with curious horn-like tusks, is not uncommon.
Another species (Macrorhinus leoninus), popularly known as the sea-elephant, is provided with short tusks and a short trunk and sometimes grows to a length of 20 ft.
Middendorff estimated the number of tusks which have yearly come into the market during the last two centuries at at least a hundred pairs, but Nordenskiiild considers this estimate too low.
Tusks are found along the whole shore-line between the mouth of the Obi and Bering Strait, and the farther north the more numerous they become, the islands of New Siberia -being one of the favourite collecting localities.
The walrus, hunted for its ivory tusks, and the sea otter, rarest and most valuable of Alaskan fur animals, are near extermination; the blue fox is now bred for its pelt on the Aleutians and the southern continental coast; the skins of the black and silver fox are extremely rare, and in general the whole fur industry is discouragingly decadent.
In the more open districts are troops of antelopes, including a variety armed with tusks, and red buffaloes.
As a rule, the teeth of the two sides of the jaws are alike in number and character, except in cases of accidental or abnormal variation, and in the tusks of the narwhal, in which the left is of immense size, and the right rudimentary.
The canines are in consequence greatly developed, of a cutting and piercing type, and from their wide separation in the mouth give a firm hold; the jaws being as short as is consistent with the free action of the canines, or tusks, so that no power is lost.
The incisors are small, so as not to interfere with the penetrating action of the tusks; and the crowns of some of the teeth of the cheek-series are modified into scissor-like blades, in order to rasp off the flesh from the bones, or to crack the bones themselves, while the later teeth of this series tend to disappear.
Sometimes they have wings of gold, brazen claws and the tusks of boars.
From this feature the name rib-faced deer has been suggested for the muntjac. The upper canine teeth of the males are large and sharp, projecting outside the mouth as tusks, and loosely implanted in their sockets.
Walrus tusks and walrus hides, which in the days of the old Norse settlements were the chief articles of export, are now of little importance.
The tusks, or upper incisor teeth, which were probably smaller in the female, in the adult males attained the length of from 9 to io ft.
Both subjects were intimately associated with the temple, for Atalanta had dedicated in it the face and tusks of the boar, which had been awarded to her as the first to wound it; and Telephus was the son of Heracles and the priestess Auge.
The tusks appear externally to the mouth, the form of the upper lip being modified to allow of their protrusion, but are much less developed in females than in males.