Cal campanulate, 10-nerved, at anthesis weakly 2-lipped, the lips slightly longer than the villous tube, the lower cleft to the base into narrowly triangular segments, the upper cleft a third its length into broadly triangular lobes, the middle one the shortest; fruiting cal enlarged, distinctly 2-lipped, distended on the lower side; cor-tube shorter than the cal, the lips about equal, the 5 lobes broadly rounded; stamens 4, nearly equal, straight, not connivent, about as long as the cor; nutlets globose, areolate; annuals, often purple or purplish, with large, long-petioled lvs and small, purple or white fls borne singly in the axils of small bracteal lvs, forming a loose, elongate, spike-like infl. 5, India to Japan.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
