Perennial rhizomatous evergreen herbs. Leaves simple, cauline or basal, alternate, opposite or subverticillate, exstipulate. Flowers regular, hermaphrodite, (4-)5-merous, solitary and terminal or in racemes, bracteate or not. Calyx of 5 united or free sepals. Petals 5, free. Stamens 10, sometimes less; filaments adnate basally to the petals; anther dehiscence porose or longitudinal. Ovary superior, (4-)5-Jocular (sometimes incompletely so) with many ovules on axile placentas. Fruit a loculicidal capsule. Seeds many, very small, embryo with poorly differentiated cotyledons.