At a height of about 7,000 feet the forest, assuming a decidedly temperate physiognomy, is chiefly composed of oaks, magnolias, chestnuts, laurels, and walnuts. In many parts arborescent rhododendrons prevail, and ferns are generally very abundant.
About 10,000 feet above the level of the sea begins a zone or belt of coniferæ, chiefly characterised by the silver fir (Abies Webbiana) and the Abies Brunoniana, a beautiful species, forming a stately pyramid, with branches spreading like the cedar, but not so stiff, and drooping gracefully on all sides. Only at intervals other trees, such as willows, magnolias, ashes, birches, poplars, apple and cherry trees, appear among the thick pine-woods. The shrubbery and herbaceous plants of this zone are representatives of the whole temperate flora of Europe and America, intermixed with many Chinese, Japanese, and Malayan plants in the richest variety. Several epiphytic orchids grow to an elevation of 10,000 feet, and large spaces are frequently occupied by rhododendrons, which either ascend from the temperate zone into the coniferous belt, or first appear in the latter. But very few trees, such as the willows, birches, maples, and ashes, rise above the coniferous forest, which reaches an upper limit of about 13,000 feet. Most arboreal plants now appear only in a dwarfed condition; but the willows still rise in powerful growth over the many Alpine shrubs—juniperus, rosa, lonicera, potentilla, rhododendron—which cover the ground; and single specimens, though low and stunted, are even found at a height of 16,000 feet.
The whole zone between the extreme limits of arboreal vegetation and the upper boundary of shrubs, generally occupies an elevation of from 13,500 to 16,000 feet, and may justly be called the region of the Alpine rhododendrons: these plants are here by far the most numerous, and frequently belt the mountains with a girdle of richly coloured blossoms, even to the verge of the perennial snows.
A large number of herbs, cruciferæ, compositæ, ranunculaceæ, grasses, sedges, grow and bloom beyond the limits of the shrubs, frequently forming luxuriant pastures, on which numerous herds of yacks or grunting-oxen, graze during the summer. Many plants are even exclusively confined to these enormous heights; such as the Rhododendron nivale, the most Alpine of woody plants, which Dr. Hooker found at 17,000 feet elevation, the Delphinium glaciale, and the Arenaria rupifraga, a curious species forming great hemispherical balls, and altogether resembling in habit the curious balsam-bog of the Falkland Islands, which thrives in similar scenes. While on the summits of the Swiss Alps, lichens but sparely cover the rocks, wherever they are denuded of snow, the wanderer in Sikkim enjoys the sight of many a gay-coloured flower in regions 3,000 or 4,000 feet higher than the summit of Mont Blanc.
MUSK-DEER.
While thus in Sikkim a wonderful variety of vegetation rises in successive zones from the foot of the mountains to heights unparalleled in any other part of the world, animal life abounds only in its lower classes; for the higher orders appear only in few species, and in very scanty numbers. On ascending from the foot of the Himalaya, one is astonished at the silence of the woods, broken at intervals only by the voice of a bird, or the chirping of a cicada. The solitude increases on penetrating into the interior of Sikkim, and is but rarely enlivened by a few monkeys in the valleys, some musk deer on the spare grass of the mountains, in heights of from 8,000 to 13,000 feet, or a few larks, sparrows, finches, pigeons, swallows, falcons, and other birds, some of which ascend to a surprising height.
The insects, however, and other invertebrata, make up, by their numbers, for the scarcity of warm-blooded animals, and are often insupportable plagues to the wanderer. Beautiful butterflies sometimes ascend to heights of 10,000 feet, along with the less agreeable mosquitoes and ticks, and in all the streams up to an elevation of 7,000 feet, hill leeches infest the waters in such multitudes that bathing is almost impossible.
