Rhizomatous or tuberous, unarmed herbs. Stems flattened to subterete.
Leaves apparently verticillate and apparently alternate, decussate or
distichous, stipules entire or bilobed, sometimes leaflike and thus apparently
absent. Inflorescences terminal or sometimes pseudoaxillary, fasciculate,
cymose-corymbiform, or umbelliform. Flowers pedicellate or sessile. Calyx limb
deeply 4 or 5-lobed. Corolla white, broadly rotate to campanulate lobes 4 or 5,
valvate in bud. Stamens 4 or 5, inserted near base of corolla tube. Ovary
2-celled, ovules numerous in each cell on axile placentas attached near top of
septum; stigma capitate or 2-lobed. Fruits capsular, subglobose to obovoid,
dehiscent through apical. Seeds numerous, small, flattened.