Fls virtually regular, produced singly or in clusters from the axils of normal or somewhat reduced foliage lvs; stamens 3 + 3, regularly disposed, but only the antesepalous ones (or 2 of them) fertile, the others staminodial; ovary and fr trilocular; herbs with leafy stems, often freely branched. 50, trop.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.