Glabrous or villosulous biennial or annual; stems 3-5 dm, commonly branched; lvs cauline, short-petioled, lanceolate, deeply pinnatifid into several narrowly oblong, crenate segments; spikes 3-8 cm, in fr to 20 cm, the bracts resembling the lvs but smaller; cal 6-9 mm, somewhat oblique, each lateral half ornamented along the margin with half a dozen short, fleshy, rounded lobes; cor 18-25 mm, pink-purple, or with purple galea, the galea with 2 short subapical teeth and another reflexed tooth near the middle of each margin; 2n=16. Wet soil; Lab. to Que. and N.S.: Eurasia. July, Aug.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.