Perennial, 4-12 dm, usually simple, short-hairy ±throughout, or rarely largely glabrate; lvs oblong to oblong-ovate or lanceolate, 5-10 cm, dentate, the lower obtuse or rounded, the upper smaller and often acute; raceme 1-3 dm, usually secund, crowded; bracts lanceolate to ovate, 1-2 cm; pedicels 2-5 mm, bibracteolate near the base or sometimes at the middle; fls 1.5-2 cm, blue, fenestrate, the lower lip glabrous within; sep lance-linear, 6-10 mm; auricles small; 2n=14. Wet soil; s. N.J. to s. O. and s. Ill., s. to Fla. and Tex. Aug.-Oct.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.