ABSTRACT
Herbaceous, terrestrial, rarely aquatic plants, glabrous, with leaves that are sometimes slightly fused at the base, sessile, entire, without stipules, and arranged opposite each other (very rarely alternate). The flowers are hermaphroditic, actinomorphic, of 4 or 5 type, gamosepalous and gamopetalous, arranged solitarily or forming cymose or racemose inflorescences, either axillary or terminal. The flowers occasionally have developed nectaries. The persistent calyx is composed of 4–8 fused sepals, rarely free. The corolla is 4–8-lobed, with twisted perfloration. The androecium consists of 4 or 5 stamens attached to the corolla tube, alternately positioned with its incisions, each with bilocular introrse anthers, and the gynoecium has a superior ovary, unilocular, with 2 parietal placentas and a glandular disc at the base. The style is simple, very short, terminated by two free or united stigmas, and the ovules are anatropous. The fruit is a septicidal capsule containing numerous albuminous seeds, globular, and edged. 1 - 4
