The Sumatran species, _Rhinoceros sumatrensis_, is to be distinguished from the last two by its two horns. It is also covered {257} by a much thicker coat of hairs, which are sometimes blacker and sometimes redder. On account of its two horns it has been proposed to separate it from the other Oriental species into a distinct genus, _Ceratorhinus_. The animal has much the same range as the last species, but extends to Borneo. A variety of this species with hairy ears, from Assam, has been separated as a distinct form, under the name of _Rh. lasiotis_, by Mr. Sclater. The animal upon which that species was founded was until quite recently living in the Zoological Society's Gardens. [Illustration] FIG. 132.--Hairy-eared Rhinoceros. _Rhinoceros lasiotis._ x 1/30. There are only two certainly-known species of Rhinoceros in Africa. These are the White Rhinoceros (_Rh. simus_) and the Black Rhinoceros (_Rh. bicornis_). The origin of the names is not easy to understand, since the "white" animal is, if anything, darker in colour than the Black Rhinoceros. It is stated, however, that in past years the specimens of _Rh. simus_ found in the south-west of Cape Colony were "paler and whiter in colour than those in the north-east." At present there are no grounds for distinguishing the species by their colour characters. But they are plainly distinguishable on other grounds. _Rhinoceros simus_ has a square upper lip, and in relation to this crops the herbage upon the ground. _Rh. bicornis_ has a prehensile upper lip projecting beyond the lower, and in a corresponding fashion feeds principally upon the branches of shrubs, It has been pointed out by Mr. {258} Coryndon[168] that the calf of _Rh. simus_ "always runs in front of the cow, while the calf of _Rh. bicornis_ invariably follows its mother." Both animals of course have two horns, and upon the varying proportions of the horns a large number of "species" have been made in the past. It is stated that the longest horn of the "White Rhinoceros" known measures 56-1/2 inches; while that of _R. bicornis_ is shorter, 40 inches being apparently the maximum. But the animal is smaller. [Illustration] FIG. 133.--Head of _Rhinoceros bicornis_. The possible third African species of _Rhinoceros_[169] has been provisionally named after Mr. Holmwood, and is based upon two horns 41 and 42 inches long, which may be abnormal horns of _Rh. bicornis_; but they are thinner and have a smaller pedicel.