Leaves all crowded at the base or whorled, linear; stipules persistent, membranous, pilose along the margins.
Perianth-segments 5, free, greenish, sometimes dorsally conspicuously horned below the apex.
Stamens 5, alternating with the perianth-segments; filaments free, linear to filiform.
Ovary superior, 3-locular, subglobose, 3-lobed, the locules multiovulate.
Inflorescences cymose, peduncled, with whorls of bracts at each node.
Fruit a membranous capsule, 3-locular, loculicidally 3-valved.
Disk hypogynous, 5-lobed, nectariferous.
Small annual herbs.
Flowers pedicelled.
Stigmas 3, short.