Fibrous-rooted perennial herb 3-8 dm; main lvs short-petioled, ovate or round-ovate, 3-6 cm, coarsely crenate, the bracteal ones smaller and narrower; cymes 4-8-fld, 1-2 cm; peduncles 2-5 mm; fls subtended by setaceous bracts; cal 10-nerved, the tube 7-10 mm, the lobes nearly equal; cor 10-15 mm, pink to white, the upper lip entire, two-thirds as long as the tube, the lower median lobe transversely oblong, emarginate; 2n=22. Native of the Mediterranean region, intr. in waste places in our range. June-Sept.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.