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..
[Enslenia Nutt. Gen. 1: 164. 1818. Not Raf. 1817.]
Perennial twining herbaceous vines, with petioled opposite cordate thin leaves, and small whitish flowers in axillary peduncled clusters. Calyx 5-parted, minutely glandular within, the segments lanceolate. Corolla campanulate, deeply 5-cleft, the lobes slightly contorted, nearly erect. Crown nearly sessile, of 5 membranous truncate lobes, each appendaged by a simple or 2-cleft awn. Stamens inserted at the base of the corolla, the filaments connate into a short tube; anthers terminated by an inflexed membrane; pollen-masses solitary in each sac, ellipsoid, pendulous. Stigma conic, slightly 2-lobed. Follicles thick, acuminate.
Seeds comose. (Greek, referring to the somewhat angled pod.]
Three species, natives of America. Type species: Gonolobus lacvis Michx.
Gonolobus laevis Michx. Fl. Bor. Am. 1: 119. 1803.
Enslenia albida Nutt. Gen. 1: 164. 1818.
A. albidus Britton, Bull. Torr. Club 21: 314. 1894.
Stem sparingly puberulent, at least above, high-climbing, slender. Leaves slender-petioled, ovate, gradually acuminate, deeply cordate, palmately veined, glabrous or very nearly so, entire, 3'-7' long, 1 1/2'-5' wide; petioles 1'-4' long; cymes numerous, densely flowered; peduncles stout, 3"-2' long; flowers 2"-3" long; corolla-segments lanceolate, acute, twice as long as those of the calyx and exceeding the 2-cleft awns of the corona-lobes; follicles on ascending fruiting pedicels, 4'-6' long, somewhat angled, glabrous when mature.
Along river-banks and in thickets, Pennsylvania to Illinois, Kansas, Florida and Texas. June-Aug.