Cal obconic, regular, strongly 10- nerved, villous in the throat, the triangular lobes a fourth as long as the tube; cor nearly regular, the tube exsert from the cal, pubescent, the upper lip erect, shallowly obcordate, the lower lip spreading, 3-lobed; stamens 2, the filaments straight, elongate, surpassing the cor; nutlets ellipsoid, smooth; perennial herbs or low shrubs, with entire or dentate lvs and small, purple to white fls in peduncled, loosely branched, trichotomous clusters terminating the stem and in the upper axils. 15, New World.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
