The hippopotamus, notwithstanding its formidable appearance, is not a dangerous enemy if suffered to go unmolested, or rather if persons do not come in its way. When wounded, however, or even intruded upon in its solitary haunts, it will attack man himself; and a boat or canoe passing along a river frequented by these creatures is in danger of suffering a similar fate to that resulting from an encounter with the great whale--that is, of being tossed out of the water or broken to pieces. The River-horse, or Sea-cow (whichever you prefer to call the creature), is exclusively confined to the African continent; and is found in all the great lakes and rivers from the Cape Colony to the southern limits of the Sahara. It is indigenous to the Upper Nile; but does not show itself in the lower half of that river. In fact, its range appears to be exactly co-terminal with that of the African elephant. There is a question about the number of species. For long it was supposed there was only one, but now it is ascertained that two, or even more, exist. The hippopotami of the Nile differ considerably from each other and also from the species known as Sea-cow in South Africa; while a smaller kind than either has been observed in the rivers of Western Africa. The _Rhinoceros_ is altogether a more curious and interesting animal than the hippopotamus; but, being more common, and oftener encountered by modern travellers, it is at present less an object of curiosity. Of rhinoceroses at least seven distinct species are known--three of them being Asiatic, and four African. The largest of all is the Indian rhinoceros, which inhabits a part of Bengal and the countries beyond--Burmah, Siam, and Cochin China. This species is easily distinguished from the others by the thick rough skin, which is placed on the animal's body in such a fashion as to resemble a coat of ancient armour. The singular protuberances have a complete resemblance to the "bosses" which were worn on the shields and breast-plates of warriors of the olden time. A second species, the Warak, which inhabits Java, is somewhat similarly accoutred; but the third Asiatic kind, the Sumatran rhinoceros, has a smoother skin, more resembling that of the African rhinoceros. These last-mentioned are denizens of the African continent; but especially of the regions extending northward from the Cape. They do not all four frequent the same district; but two, and sometimes three of them, are found in one locality. They are distinguished as the black and white rhinoceroses--there being two species of the black, and two of the white. The black ones are much fiercer than their white congeners; although the latter are by far the largest, and present a far more formidable appearance, from the extreme length of their horns.