the mountains, takes place at considerable elevations, from the operation of other causes. This being com- bined with moisture, we have two of the characteristics of a tropical climate, and find that, in such circumstances, a less degree of heat is essential for the maintenance of plants otherwise indicative, though only annuals, of tropical vegetation. Of these may be instanced one of the Scitaminece, the family to which the ginger and cardamom belong, at as great an elevation as nine thousand feet, with Bal- sams, Begonias, Cyrtandracetx, Melastomacece, a Smithia, Cassia, &c. : even a Bamboo is found as high as ten thou- sand feet ; but its annual stems are yearly levelled by the falls of snow, while the roots are protected by their sub- terranean situation from the great changes of temperature. It is this moist state of the atmosphere, and the frequent showers previous to its accession, which render practicable, at considerable elevations in these mountains, the cultivation of rice ; an annual that ripens in a few months. This shews how futile was the attempt to cultivate it in this country, merely because there appeared to those who thought only of temperature, a similarity in climate.
But luxuriant vegetation is not confined to tropical countries, as we know from the beauty and variety of scenery in temperate climes, dependant on an entirely different set of plants. Among these, the Coniferce are conspicuous ; and the Amentacece give the greatest variety of trees, as oaks, chestnuts, birches, horn-beams, hazels, poplars, and willows ; with elms, maples, rhododendrons, and the walnut, which, though found in southern latitudes, grow in mountainous situations only. But these are not more indicative of moderate temperature than are many other families of plants ; as the Ranunculacece, Gentianece, Primulacece, Saxifragece, Valerianece, Campanulacece, Rosacece, some tribes of Labiates, Cruciferce, Caryo-
