High-climbing vine; lfls 9-15, ovate-oblong or lance-ovate, 4-6 cm, acuminate, obscurely hairy beneath; racemes compact, 4-15 cm; pedicels 4-10 mm; axis, pedicels, and cal finely pubescent and also with some short-stipitate, oblong or clavate glands; fls blue-purple, 1.5-2 cm; cal campanulate, the upper 2 lobes broadly triangular to almost completely connate, forming an upper lip to about a third as long as the tube; lower lobes lanceolate, the median slightly the longer; blade of the wing-pet prolonged backward into a linear auricle about as long as the claw and ±parallel to it; fr glabrous; 2n=16. Moist or wet woods and river-banks; Va. to Fla. and Tex., n. in the interior to Ark. Late Apr., May.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.