BEGONIA, a genus of 400 to 500 species of succulent tropical herbs or under-shrubs of the family Begoniacece, most abundant in Mex ico and Central and South America. Since the introduction of the first species (B. nitida) into England in 1777 about 200 species have been utilized by horticulturists, who have pro duced thousands of varieties noted for the superb coloring of either or both their flowers or foliage. In general the plants are charac terized by variable, lop-sided (except in one group), alternate, entire or lobed leaves; axil lary cymes of usually large moncecious flowers, varying in all shades of red, also white and yellow; numerous stamens free or basally united; two to four styles; branched or twisted stigmas; and three-winged capsular, often col ored, fruits containing numerous tiny seeds. The cultivated varieties may be grouped into (1 ) summer-flowering or tuberous-rooted, which produce large single and double flowers; (2) winter-flowering or fibrous-rooted; (3) semi-tuberous, with peltate leaves; (4) orna mental-leaved, or rex, Asiatic species and their descendants, with remarkably handsome or striking foliage. There are also hybrids between
members of these groups. Each group demands somewhat different cultural treatment, but in general the tuberous sorts are started from seeds, and the tubers thereafter used from year to year; other varieties are usually increased by means of cuttings, either of stem or of the leaf, by various methods almost confined to this group of plants. The varieties are usually easy to cultivate, but some, especially the tuber ous sorts, are somewhat sensitive to dryness of atmosphere and hot sun, which usually accounts for the poor behavior of these plants in houses heated by hot air, steam or hot water. For description of species grown in America, and tor details of propagation, cultivation, etc., con sult Bailey,