Page:Encyclopædia Britannica, Ninth Edition, v. 20.djvu/540

Rh 522 RHINOCEROS The existing species of rhinoceros are naturally grouped into three sections, which some zoologists consider of generic value. I. Rhinoceros proper. The adults with a single large compressed incisor above on each side, and occasionally a small lateral one; below, a very small median, and a very large, procumbent, pointed lateral incisor. Nasal bones pointed in front. A single nasal horn. Skin very thick, and raised into strong, definitely arranged ridges or folds. There are two well-marked species of one-horned rhino- ceroses. (1) The Indian Rhinoceros, R. unicomis of Lin- naeus, 1 the largest and best known, from being the most frequently exhibited alive in England, is at present only Fia. 2. Indian Rhinoceros (Rhinoceros unicornis). This and the following woodcuts are reduced from drawings by J. Wolf, from animals living in the London Zoological Society's Gardens. met with in a wild state in the terai region of Nepal and Bhutan, and in the upper valley of the Brahmaputra or province of Assam, though it formerly had a wider range. FIG. 3. Javan Rhinoceros (Rhinoceros sondaicus). The first rhinoceros seen alive in Europe since the time when they, in common with nearly all the large remarkable beasts of both Africa and Asia, were exhibited in the 1 Many authors use Cuvier's name, R. indicus, in preference to this, on the ground that there are more than one species with one horn, forgetting that the name substituted is equally inconvenient, as more than one species live in India. The fact of a specific name being applicable to several members of a genus is no objection to its restriction to the first to which it was applied ; otherwise changes in old and well-received names would constantly have to be made in consequence of nsw discoveries. Roman shows, was of this species. It was sent from India to Emmanuel, king of Portugal, in 1513 ; and from a sketch of it, taken in Lisbon, Albert Diirer composed his cele- brated but rather fanciful engraving, which was repro- duced in so many old books on natural history. (2) The Javan Rhinoceros, R. sondaicus, Cuvier, is distinguished by smaller size, special characters of the teeth and skull, and different arrangement of the plications of the skin (as seen in the figures) ; the horn in the female appears to be very little developed, if not altogether absent. This has a more extensive geographical range, being found in the Bengal Sunderbans near Calcutta, Burmah, the Malay Peninsula, Java, Sumatra, and probably Borneo. II. Ceratorhinus. The adults with a moderate-sized compressed incisor above, and a laterally placed, pointed, procumbent incisor below, which is sometimes lost in old animals. Nasal bones narrow and pointed anteriorly. A well-developed nasal, and a small frontal horn separated by an interval. The skin thrown into folds, but these not .so strongly marked as in the former section. The smallest living member of the family, the Sumatran Rhinoceros, R. sumatrensis, Cuv., belongs to this group. Its geo- graphical range is nearly the same as that of the Javan species, though not extending into Bengal; but it has been found in Assam, Chittagong, Burmah, the Malay Peninsula, Sumatra, and Borneo. It is possible that more than one species have been confounded under this designation, as two animals now living in the London Zoological Gardens present considerable differences of form and colour. One of them, from Chittagong, has been named by Sclater R. lasiotis, the Hairy-Eared Rhinoceros, but until an opportunity is afforded for anatomical ex- amination, it is difficult to pronounce upon the value of the distinction. III. Atelodus. In the adults, the incisors are quite rudi- mentary or entirely wanting. Nasal bones thick, rounded and truncated in front. Well-developed anterior and pos- terior horns in close contact. Skin without any definite permanent folds. The two well-marked existing species are peculiar to the African continent. 1. The common Two-Horned Rhinoceros, R. bicornis, Linn., is the smaller of the two, with a pointed prehensile upper lip, and a narrow compressed deep symphysis of the FIG. 4. Common African Rhinoceros (Rhinoceros bicornis). lower jaw. It ranges through the wooded and watered districts of Africa, from Abyssinia in the north to the Cape Colony, but its numbers are yearly diminishing, owing to