Annual or perennial herbs or sometimes dwarf-shrubs. Leaves opposite,. linear or subulate, rarely oblong or lanceolate, exstipulate. Flowers small, in dichasial . cymes or solitary, terminal. Sepals 5 (4), free. Petals 5 (4 or 0), white or pinkish, entir or retuse. Stamens 10 or rarely less, inserted on the perigynous disk with simple or 2-fid lobes. Ovary 1-celled, usually many-ovuled; styles 3, sometimes more. Capsule dehiscing by 3 (-5) valves or teeth. Seeds many, almost reniform.