Cal campanulate to tubular, entire or lobed, usually oblique and longer on the upper side; cor very irregular, the tube gradually enlarged distally, the upper lip (galea) as long as or longer than the lower, curved forward and very concave or arched, often laterally compressed, entire or with 2 lateral teeth near the tip, the lower lip ±expanded, with
2 longitudinal folds below the sinuses; stamens 4, paired, ascending under the upper lip, included; stigma capitate; fr much compressed, ovate or oblong, usually falcate or inequilateral, loculicidal, but usually opening only or most deeply on the upper side; hemiparasitic herbs with opposite or alternate, sharply toothed to bipinnatifid lvs and medium-sized yellow to red or purple fls in terminal, leafy-bracteate spikes or racemes. 500, mainly North Temp. and boreal, also in the Andes.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.