Cal campanulate, nearly regular, the narrowly triangular lobes exceeding the tube; cor-tube included in the cal, the upper 4 lobes spreading or ascending, the lower one deflexed, usually slightly longer; stamens 4; filaments nearly straight, shortly exsert from the tube; fruiting cal accrescent, obscurely reticulate; nutlets prominently reticulate-areolate; annual with 1-3 fls from the axils of the scarcely reduced bracteal lvs, forming a large leafy panicle. Monospecific.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
