Sardinia fully confirms the observation regarding the identity of the physical character of countries on two sides of the same sea. There does not exist a more senseless notion than to imagine that rivers form the natural boundaries between two countries; the same physical features appear on both sides of a river: rivers are lines of communication, but mountains separate countries from one another. The Suabian and Bavarian races are separated by the range of the Vorarlberg. Sardinia, in its physical structure, belongs to Africa, if not wholly, at least its southern part as far as the mountains. This character shows itself both in the vegetation and in the animal life of the country: the _musimon_, an animal foreign to all the rest of Europe, is not found anywhere out of Africa except in Sardinia.[62] The character of the population also is African, whence Cicero, in his speech for Scaurus, says: _Afer aut Sardus sane, si ita se isti malunt nominari_. The island is not, like Sicily, traversed by lofty mountains; it is only in the northern part that the mountains reach any considerable height; the rest is only a hilly country; many parts of the coast are plains, extensive and low marshy districts, which may be termed savannahs, whence great quantities of salt are obtained there. The physical identity with Africa manifests itself also in another very important point: the opposite coasts of Sardinia and Africa are celebrated for their banks of coral, while they are not found near Sicily, Spain, or the Balearian islands.[63]