Fls perfect or sometimes unisexual; cal-tube (5-)10-30- veined, with 5 short teeth, variously hairy or glandular or glabrous, sometimes inflated; pet 5, the claw narrow, usually expanded above into evident auricles at the juncture with the blade, and usually with a pair of appendages on the inner surface at the juncture; stamens 10, styles 3, less often 4 or 5, rarely more; ovary usually stipitate, the stamens and pet often adnate to the stipe; capsule unilocular or more or less completely plurilocular, dehiscent by twice as many teeth as the number of styles, or less often by only as many teeth as styles; seeds reniform to globose, roughened; annual to perennial herbs with opposite (seldom whorled), entire, exstipulate lvs. 400, mostly N. Temp.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.