Cal 13-nerved, naked in the throat, 2-lipped, the upper lip much the longer; cal-lobes narrowly triangular to subulate; cor 2-lipped, villous, the tube elongate, usually outcurved, the upper lip straight, subgaleately concave, entire, the lower about as long, spreading or deflexed, with 2 broad lateral lobes and an oblong median one; stamens 2, ascending under the upper lip and eventually exsert, their anthers connivent; rhizomatous (sometimes also stoloniferous) perennials with numerous pale purple fls densely crowded in the axils of the upper lvs. Only the following 2 spp.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.