Cal regular, deeply 5-parted; cor tubular or campanulate, very irregular, saccate-gibbous at base between the 2 lower sep, 2-lipped, the lower lip with a prominent palate closing the throat; stamens 4; stigma capitate; fr asymmetrical, opening by subterminal pores; herbs with handsome, often bicolored fls and narrow, entire lvs, the lower opposite, the upper alternate. 35, w. Eurasia and w. N. Amer.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.