This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol3", by Nathaniel Lord Britton, Addison Brown. Also available from Amazon: An Illustrated Flora of the Northern United States, Canada and the British Possessions. 3 Volume Set..
[Dicliptera Juss. Ann. Mus. Paris, 9: 267. 1807.] Erect or diffuse branched pubescent or glabrous herbs, with entire petioled leaves, and blue red or violet flowers, subtended by involucres of 2-4 distinct or connate bracts, the inflorescence mostly cymose or spicate, the involucres subtending 1 flower or several. Calyx 4-5-cleft, the lobes linear or subulate. Corolla-tube slender, slightly enlarged above, the limb conspicuously 2-lipped; upper lip erect, concave, interior in the bud, entire or 2-3-toothed; lower lip spreading, entire or 3-toothed. Stamens 2; anther-sacs parallel, sometimes unequal, separated by a narrow connective. Style filiform; ovules 2 in each cavity of the ovary. Capsule flattened, ovate or suborbicular, sessile or stipitate, 2-4-seeded. Placentae separating elastically from the walls of the capsule. Seeds compressed, nearly orbicular.
About 60 species, natives of warm and tropical regions. Besides the following, 4 others occur in the southern and southwestern United States. Type species: Justicia chinensis L.
Annual (?), glabrate, or pubescent; stem slender, 6-grooved, erect, much branched, 1°-2° high. Leaves ovate, membranous, long-petioled, acuminate or acute at the apex, narrowed or rounded at the base, 3'-6' long, 1'-3' wide; inflorescence paniculate, the involucres 1-4-flowered, each of 2 oblong or obovate, obtuse or mucronate, opposite bracts; corolla 8"-12" long, pink or purple, the lips about as long as the slender tube; upper lip 2-3-toothed, the lower entire; capsule oblong, 2"-3" high, a little longer than the involucre, the valves slightly divergent in dehiscence, the placentae remaining attached to their summits.
In moist thickets, North Carolina to Florida, Missouri, Kansas and Texas. July-Oct.