RHODODENDRON, a genus of trees and shrubs of the natural order Eri cacem, having 10 stamens, a very small calyx, and a bell-shaped or somewhat funnel-shaped corolla. The buds in this and nearly allied genera, as azalea, are scaly and conical. The species are nu merous; they have evergreen leaves, and many of them are of great beauty, both in foliage and in flowers. A few small species are natives of continental Eu rope and of Siberia ; but the greater number belong to the temperate parts of North America, and to the mountains of India. R. maximum, so designated when the far larger Indian species were unknown, is common in North America as an ornamental shrub. It is a large shrub or small tree, which forms im penetrable thickets on many parts of the Allegheny mountains. The leaves are large, leathery, dark green and shining above, rusty brown beneath. The flow ers are large, varyirig in color from pale carmike to lilac. This species is quite hardy in Great Britain; as is also R. ponticum, a very similar species, with narrower and more pointed leaves, which are of the same color on both sides, a native of western Asia, and apparently also of the S. of Spain. R. eatawbiense, a native of the S. parts of the Alle ghenies, with large purple flowers; R. Caucasicum, the name of which indi cates its origin; and R. arboreum, a native of Nepal, with very dense heads of large scarlet flowers. Most of the extremely numerous varieties now com mon in our gardens and shrubberies have been produced from them by hy bridizing or otherwise.
Many splendid species of rhododen drons were discovered in the Himalayas, the Khasia hills, and other mountainous parts of India, and have been introduced into cultivation in Europe. R. Falconeri is described as in foliage the most su perb of all, the leaves being 18 or 19 inches long. It is a tree 30 to 50 feet high, with leaves only at the extremities of the branches. It grows in eastern Nepal at an altitude of 10,000 feet. R.
argenteum has flowers 41/2 inches long, and equally broad, clustered, and very beautiful. R. Maddeni, R. Aucklandii, R. Edgeworthii, and others have white flowers. R. Dalhousie is remarkable as an epiphyte, growing on magnolias, lau rels, and oaks. It is a slender shrub, bearing from three to six white lemon scented bells, 41/2 inches long, at the end of each branch. R. Nut tali has fragrant white flowers, said to be larger than those of any other rhododendron. All these belong to the Himalayas. In more southern latitudes, as on the Neilgherry Hills and on the mountains of Ceylon, R. nobile prevails, a timber tree 50 to 70 feet high, every branch covered with a blaze of crimson flowers. R. Keysii and R. Thibaudiense, also natives of the N. of India, have flowers with nearly tubular corolla. R. ferrugineum and R. hirsutum are small species, natives of the Alps. They are called Alpenrose (Alpine rose) by the Germans. They have small carmine-colored flowers. The flora of the Himalayas contains a num ber of similar small species. R. antho pogon and R. setosum, dwarf shrubs with strongly scented leaves, clothe the mountains in eastern Nepal. R. nivale is the most alpine of woody plants, spreading its small woody branches close to the ground at an elevation of 1,700 feet in Sikkim. R. lapponicum, a pro cumbent shrub, with small flowers, grows as far N. as human settlements have reached in Europe, Asia, and the United States. An oil obtained from the buds of R. ferrugineum and R. hirsutum is used by the inhabitants of the Alps, under the name Olio di Marmotta, as a remedy for pains in the joints, gout, and stone. R. chrysanthum, a low shrub, with golden yellow flowers, a native of Siberia, is also used in gout and rheu matism. R. cinnabarinum, a Himalayan species, poisons goats which feed on it. But the flowers of R. arboreum are eaten in India, and Europeans make a palat able jelly of them.