RHINITIS. interference in the way of removal of hypertro- phic tissue, botl uiueuus iiieinbrane and bone, as well as the correction of intra-nasal cicfdrniilies. Hay fever (q.v.) is sonietiiiies termed 'pruriyin- ous rhinitis.' Khinilis ulcerosa is considered nnder Ozena. For a study of the bacteriology of nasal inllammation, see Howard, in American Joiirnnl of the Medical Scieiwesi. EHINOCEKOS (Lat. rhinoceros, from Gk. i>iv6K£pu(, rliinokeros, rhinoceros, nose-horned, from /i(f , rhis, nose -)- Ktpui;, kerOs, horn ) . An animal of a family of perissodactyl ungulates (q.v.), the Rhinoeerotida;, closely allied to the tapirs, and containing the largest and most pow- erful of terrestrial mammals, except the ele- phants. There are five existing species, all na- tives of the warm parts of Asia, the Indian Archipelago, and Africa. The form of the rhi- noceros is massive and uncouth. The limbs are thick and strong; each foot is terminated by three nearly equal toes, covered with broad, hoof- like nails, with a fourth non-functional toe on the. front feet. The tail is small and terminated by a small tuft. The head is large, the muzzle prolonged, ears moderately large, ej'es small, and nasal bones combined into an arch for the sup- port of a horn or horns. The upper lip in most species is prolonged, pointed, and prehensile. Tne incisors are defective in the Asiatic species, and, as well as the canines, wanting altogether in the African species: the molars and pre- molars are alike and highly effective as grinders. The skin is extremely thick and smooth, but soft and sensitive, although in the Asiatic species it has the appearance of a rigid armor, studded with tubercles and jointed in folds or wrinkles where necessary to permit movement of the head and limbs. The hide is used for making whips, harness, ropes, and so on, and when dried and hardened forms a material for shields capable of resisting spear thrusts and old-fashioned bul- lets. When properly dried and prepared it has the translucency and mottled appearance of tor- toise-shell, and from it are made various orna- mental objects by East Indian artificers. The nasal horn or horns are formed of a solid mass of agglutinated bristles which spring from the skin of the nose, but are rooted upon a bony plate surmounting the skeleton of the nose. This horn is not only a powerful weai^on, but with it the animal can root up and overturn bushes and small trees whose leaves and roots it seeks to eat. The Indian rhinoceros (Rhinoceros Indicus) formerly ranged over most of the peninsula, but is now restricted almost entirely to the Assam plain, and lives chiefly in grassy jungles. It is the largest known species and sometimes exceeds five feet in height and ten feet in length. The single horn is sometimes two feet long and eight- een inches in eircimiference at the base. The Ja- vanese or Sondaic rhinoceros (Rhinoceros Son- daicus) is a much smaller species, also one- horned, found from Bengal to Java. Its armor has a tessellated appearance, and the female is hornless. The Sumatran or hairy rhinoceros [Rhinoceros Sumatrensiis) is so distinct that some naturalists have placed it in a .separate genus ' (Cetorhinus) . It ranges from Northeast- ern India to Borneo, has a more hairy coat than the others, and two short blunt horns, one behind the other. A haii-y-eared race (var. lasiotis) inhabits Assam. 99 RHINOCEROS. The two species of African rhinoceros differ from the Asiatic ones mainly in the absence of incisor teeth and in the sinoollicr, unfolded skin; and they have been put into a separate genus (.Uelodus) by some naturalists. Possibly a third species exists, of which nothing very defi- nite is known. The more familiar and" wide- spread of the African rhiiioceioses is the 'coin- mon' or 'black' one (Rhinoceros bieontis) former- ly abundant all over the eastern and south-cen- tral ]iarts of the continent, but now become rare and restricted. It is not black, but bluish lead- color, if anything rather lighter than the oilier species usually called 'wliitc.' This rhinoceros stands rtVj feet at the withers in the lase of large males or -bulls,* and has two horns. The front one, usually much the longer in South African examples, sometimes attains a leiigtli of 40 inches, but is always less in northeni s|ieci- luens. The rear horn varies from a mere knob to a length almost equal to its fellow, and is usually straighter and much compres.seil. The upper lip is pointed, extensible, and prehensile, and this species feeds almost wholly on leaves, twigs, and roots. It, frequents bushy and rocky districts rather than open plains, li spends the day in an accustomed lair well hidden from ob- servation, and starts at sunset for a drinking- place along a well-trodden path. Having drunk it will wander about feeding during the night, will drink again at daybreak, and then return to its resting-place. Some hunters regard this rhi- noceros as naturally ferocious and vindictive, while others consider it stupid and timid, but subject to sudden panics, in which it is as likely to rush headlong toward the hunter as away from him. At best, however, it is dangerous, and its speed and agility arc extraordinary. The other African .species, the white, Burchell's or square-mouthed rhinoceros (Rhinoceros simus), is larger than the 'bicornis,' the biggest, indeed, of the entire tribe, and dilfers from the other prominently in having a blunt, squarish muzzle, the upper lip not being at all prelicn- sile. In conformity with this it is a grazing, not a browsing animal. Fos.siL Rhinoceroses. The existing species are the lone remnants of a once numerous group that abounded in North America from Eocene to late lliocene time, and in Europe from Eocene to Pliocene time. The fossil and living species may be grouped under three families. The Hyracodontida'. represented by the genera Hyra- chyus and Hyracodon of Eocene and Oligoccne time, comprised hornless, lightly built animals adapted for running on the uplands. They show a tendency to reduce the number of functional digits of the feet from five to three and thus to parallel the evolution seen in the horse's hoof. The Am. iodontida'. comprising the American genera Amynodon, Metamynodon. and the Euro- pean Cadurocotherium, were heavily built, short- bodied animals adapted to more or less aquatic habits of life. The skull was hornless and the eyes were situated high on the head. The up]>cr incisors are reduced and the canine teeth are enlarged to form tusks for use in uprooting water plants. The true rhinoceroses (Rhinocero- tidse) began as light-limbed runners without horns, that lived at the same time as the mem- bers of the two preceding families. After the hyracodonts and amynodonts had become extinct the rhinoceroses began to adapt themselves to
