has only three instead of four nails on each hind foot. In like manner, not one of three African species of Rhinoceros agrees with one of the three Indian kinds.
3dly. The Southern region of Africa, where that continent extends into the temperate zone, constitutes another separate zoological province, surrounded as it is on three sides by the ocean, and cut off from the countries of milder climate in the northern hemisphere, by the intervening torrid zone. In many instances, this region contains the same genera which are found in temperate climates to the northward of the line: but then the southern are different from the northern species. Thus, in the south we find the quagga and the zebra; in the north, the horse, the ass, and the jiggetai of Asia.
The south of Africa is spread out into fine level plains from the tropic to the Cape. In this region, says Pennant, besides the horse genus, of which five species have been found, there are also peculiar species of rhinoceros, the hog, and the hyrax, among pachydermatous races; and amongst the ruminating, the Cape buffalo, and a variety of remarkable antelopes, as the springbok, the oryx, the gnou, the leucophoa, the pygarga, and several others.[874]
4thly. The assemblage of quadrupeds in Madagascar affords a striking illustration of the laws before alluded to, as governing the distribution of species in islands. Separated from Africa by the Mozambique channel, which is 300 miles wide, Madagascar forms, with two or three small islands in its immediate vicinity, a zoological province by itself, all the species except one, and nearly all the genera, being peculiar. The only exception consists of a small insectivorous quadruped (Centetes), found also in the Mauritius, to which place it is supposed to have been taken in ships. The most characteristic feature of this remarkable fauna consists in the number of quadrumana of the Lemur family, no less than six genera of these monkeys being exclusively met with in this island, and a seventh genus of the same, called Galago, which alone has any foreign representative, being found, as we might from analogy have anticipated, in the nearest main land. Had the species of quadrupeds in Madagascar agreed with those of the contiguous parts of Africa, as do those of England with the rest of Europe, the naturalist would have inferred that there had been a land communication since the period of the coming in of the existing quadrupeds, whereas we may now conclude that the Mozambique channel has constituted an insuperable barrier to the fusion of the continental fauna with that of the great island during the whole period that has elapsed since the living species were created.
5thly. Another of the great nations of terrestrial mammalia is that of India, containing a great variety of peculiar forms, such as the sloth-bear (Prochilus), the musk-deer (Moscus), the nylghau, the gibbon or long-armed ape, and many others.