Rhinoceros (Gr. , nose, and , horn), an ungulate mammal, surpassed in size among present terrestrial animals only by the elephant, and perhaps by the hippopotamus. The head is long and triangular, and from the upper surface of the end of the nose springs a single or double horn, composed of a solid mass of agglutinated hairs or horny fibres; this is supported on the nasal bones, though not connected with them, belonging entirely to the skin and removed with it; it is often more than 3 ft. long, and gently curved backward, and so sharp as to make it a very formidable weapon; when there are two horns, the hinder is generally much the shorter. There are no canine teeth, and the incisors sometimes fall out when the animal is full-grown; the molars are 7/7-7/7, with lunate ridges; the nose is blunt and rounded, and the upper lip elongated and very movable; the eyes are small, and the ears moderate, tipped with rigid hairs; the body is very bulky, the legs short and strong, and the feet three-toed with as many broad hoofs; the tail is short, round at the base, compressed laterally toward the end, and hairy at the tip; on the hind feet are sebaceous glands opening on the posterior surface, in a sacculated inversion of the skin, as on the anterior surface of the feet of sheep; the mamma are two, and inguinal.
The skin is naked, very rough and hard, divided into large folds which give to the animal a shielded appearance; it is impervious to the claws of the lion and tiger, will turn the edge of a sword, and is impenetrable to ordinary musket bullets. The stomach is large and simple, the intestinal canal eight times as long as the body, the villi of the small intestine greatly developed, the large intestine very wide, and the caecum sacculated. The ribs are 19 pairs, the iliac bones very wide, and the femur with a prominent ridge on the outer border terminating in a hook-like process and with the great trochanter exceedingly prolonged; the incisor teeth seem to be developed in an inverse ratio to the horns; the brain is large, but the relative size of the cerebrum, especially the upper and anterior portion, is less than in the elephant. The rhinoceros is found in the warm regions of Asia and Africa, living with the elephant in forests, and feeding on herbage and leafy twigs and shrubs. It is peaceable unless irritated; it then charges upon its enemy with the head down and the horn forward; though not very active, its great weight and strength make it a formidable assailant, and a match even for the elephant.
The senses of smell and hearing are so acute that the hunter must approach against the wind and in perfect silence; it is hunted for sport by Europeans, and the natives eat the flesh, and sell the skin to traders for the manufacture of canes, whips, and defensive armor, and the horns for boxes and cups. In its native forests the rhinoceros has a tortoise-like appearance, with its stolid expression, slow movements, thick armor, short legs and tail, and curved upper lip. - Several species have been described, of which the best known is the single-horned or Indian rhinoceros (R. unicornis, Linn.; R. Indicus, Cuv.). This animal measures about 12 ft. in length, with a circumference of the same, and a height of 6 ft.; the skin is very thick, arranged in broad folds in many parts, rough and tubercu-lated, and deep purplish gray. It was well known to the ancients, and is generally believed to be the unicorn or reëm of the sacred writings, though not of the Arabian poets, which was either a wild bull or an antelope.
It leads a quiet indolent life, wallowing on the marshy borders of rivers and lakes, and bathing in their waters; it moves slowly, the head carried low as in the hog; its strength enables it to pass with ease through the thickest jungles; it is found in the warmer parts of continental India. In captivity, especially if taken young, it is gentle, obedient, and grateful for kind treatment, with occasional paroxysms of rage without apparent cause; it is fond of bread, fruit, and particularly sweets, collecting and holding its food by the long upper lip; it is not uncommon in menageries, and has been trained to perform simple tricks, but its intelligence is far inferior to that of the elephant; though these two animals are said to have a natural antipathy to each other, they agree very well together in confinement. The Java rhinoceros (E. Sondaicus, Horsf.), with a single horn, is confined to Java; the epidermis is arranged in pentagonal shields. The Sumatran rhinoceros (R. Sumatrensis, Cuv.) is a smaller species with two horns and a comparatively smooth skin.
For an account of its breeding see Maunder's "Treasury of Natural History" (London, 1874). - The black African rhinoceros (R. bicornis, Linn.; R. Africanus, Camper), the borélé of the S. African aborigines, has two horns, and a smoother skin, wrinkled instead of folded; the incisors are either latent or fall away early; the horns, which as in the other species occur in both sexes, are brightly polished by rubbing against the trees, and the posterior is only one third the length of the anterior, the latter being rarely more than 18 in. The general color in the male is black, in the female pale yellowish brown with purplish tints on the head, and the groins flesh-colored; the head seems too deep in proportion to its length, giving it a very clumsy appearance; the upper lip is scarcely at all prolonged; the neck short and thick, with a deep furrow where it joins the head, and a rudimentary hump on the shoulder. In size and habits it resembles the Indian species; it was formerly found even on the slopes of Table mountain, but has now been driven far beyond the limits of Cape Colony into the interior, where it is seldom molested.
They keep concealed by day, wandering at night in search of water and food, especially the branches of the wait-a-bit thorns; the gait is equal to that of a good horse, and when disturbed the head is carried high; they are usually seen singly or in pairs. They are suspicious and savage, attacking the traveller, and so lean that the flesh is rarely eaten; wherever the footprints are seen, the ground and bushes are found torn up; this they do, not from rage, but in a mere wanton display of strength; they also dig the ground with the fore feet, throwing it backward in the manner of a dog. Dr. A. Smith, in his "Zoology of South Africa," makes three species; Dr. Livingstone considers that all the species made by naturalists beyond two are based on mere differences in size, age, and direction of horns, which vary much within the limit of a single species. The R. keitloa (A. Smith) is a rather smaller species, with two horns nearly equal in length, with more slender head and longer neck than in the borélé; the general color is pale brownish yellow, with a black mark on the inside of the thighs; the upper lip is elongated; it is swift, fierce, and dangerous, comparatively rare, and not found further south, than lat. 25°. - The white rhinoceros (R. simus, Burch.), the mohoohoo of the Bechuanas, is the largest of the genus; the color is pale brownish white, with purplish tints on the shoulders and posterior parts; the head is comparatively long and slender, the face concave, forehead convex, neck long with three well marked wrinkles on nape, the nose truncated, the upper lip perfectly square and ox-like, and the shoulders with a distinct hump; the horns are two, the first very long and pointed, the second just behind it, short and obtuse.
This is a rare species, timid, unsuspecting, easily captured on account of its slow movements, and much prized by the natives for its fat flesh; the food is principally grass. The Bechuanas call the rhinoceros by the general name of chukuroo. The best friend of this animal is a bird of the genus buphaga, known as the rhinoceros bird, which warns it of the approach of danger. It makes a harsh cry in the ear of the sleeping rhinoceros, which awaking rushes off into the forest to escape the hunter; it perches on the animal's back, returning when frightened or swept off by the branches, and remains with it all night. Cumming says he has often shot the rhinoceros at midnight at fountains, and that these birds, imagining "chukuroo" was asleep, would remain until morning, and on his approaching, before taking flight, would try to awaken him from his deep sleep. - The rhinoceros played an important part among the animals of the tertiary and diluvial epochs, numerous species of great size occupying cold countries of Europe, where they now could not exist.
Since 1781 many fragments have been found in Germany, Italy, France, England, and Russia. A few species have been detected in the lower miocene of France, of which the R. tapirinus (Pomel), of the size of a tapir, belonged to Kaup's group of acerotherium, characterized by two large incisors in each jaw, four toes on the anterior feet, and probably a very small, if any, nasal horn. In the upper miocene of France and Germany occur many species which De Blain-ville has united into the single R. incisivus, without bony partition between the nostrils, with two large incisors in each jaw and three toes on each foot. In the pliocene of France and England are species without bony nasal partition and with moderate incisors, like the R. megarhinus (Cuv.). The best known fossil species is the R. tichorhinus (Cuv.), of the diluvial deposits of Siberia and the most of Europe, contemporary with the mammoth. The most remarkable specimen was found in 1731 in arctic Siberia by a hunter; the body was well preserved and half buried in the frozen sand, in lat. 64° N.; it was 11 1/2 ft. long, with a skin like leather covered with short hair; the nasal bones were curved in front of the nose to unite with the intermaxillaries, and the partition between the nostrils was bony to the extremity, giving greater solidity to the nose for the support of the two large horns, which were further separated than in the living species; the incisors fell but in the adults, and the symphysis of the lower jaw was very long; coming nearest to the R. bicornis of Africa, it had a longer and narrower cranium, more bulky body, and shorter and stouter limbs.
It occurs in diluvial sands, in caverns, and in bone breccia. This genus has also been found in the tertiary and diluvial deposits of Asia; Cautley and Falconer describe four species among the Sivalik hills of northern Hindostan. The most singular fact in connection with the geological distribution of the rhinoceros is its occurrence during the diluvial period in America, like the elephant not now existing on this continent; several species differing from R. tichorhinus are described by Profs. Leidy, Marsh, and others, from the tertiary of Nebraska, Texas, the upper Missouri, California, and the neighoring territories. The genus elas-motherium of Fischer probably comes near if not in the rhinoceros family; judging from the teeth, and the size, form, and thickness of jaw, it must have been an animal of heavy proportions, with the size and habits of the rhinoceros, and essentially herbivorous; it was found in Siberia. The family brontotheridoe, so fully described by Profs. Marsh and Cope, from the miocene of Colorado and the adjoining territories, seems to have combined some of the characters of the rhinoceros and elephant, which succeeded them in the pliocene period.
Black African Rhinoceros (Rhinoceros bicornis).