Fls perfect, ±irregular; pedicels without bracteoles; hypanthium very short; sep 5; pet 5, yellow, often unequal; stamens mostly 10 but unlike, the lowest (abaxial) ones fully developed, the upper ones progressively reduced, in our spp. the 3 upper ones without normal anthers; anthers basifixed, at least half as long as the filaments, opening by an apical pore or short slit; pods terete or quadrangular to compressed, often transversely septate, indehiscent or inertly dehiscent; lvs evenly once-pinnate, generally with one or more large glands on the petiole or rachis; our spp. all herbs. (Often included in Cassia) 240, widespread.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.