Fls irregular, 6-merous; hypanthium tubular, prominently 12- ribbed, swollen or spurred at the base on one side, oblique at the mouth; stamens usually 11 or 12, alternately unequal; pet unequal; ovary with a curved gland at its base, imperfectly 2- locular; style slender; capsule included in the hypanthium, opening along the upper side, the hypanthium also splitting along the upper side; herbs or shrubs with opposite lvs and solitary or racemose fls. 200+, mainly tropical and subtropical Amer.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
