Cal narrowly obconic, 4-lobed, the lobes separate to the middle except on the lower side, where the cleft extends to the base; upper lip of the cor lacking, the lower lip 3-lobed, its median lobe much longer than the other 2 and incurved; stamens 2 (the lower pair), inserted near the cor-throat, the filaments like those of Lindernia; style deeply bifid; fr rupturing irregularly; small glabrous annuals with opposite or whorled, sessile lvs and minute axillary fls. 10, the others in tropical Amer.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
