Hypanthium saucer-shaped; sep 5; bractlets none; pet 5, cuneate-obovate; stamens 5, opposite the pet, with short filaments; ovaries 5-10, rarely more; ovule ascending; style nearly basal, slender, jointed below; fr an achene; taprooted perennial herbs with ternately decompound cauline lvs and ample bracteate cymes of numerous small, white or purplish fls. 5, all but ours strictly Siberian.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
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