This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol2", 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..
Phaseolus leiospermus T. & G. Fl. N. A. 1: 280. 1838.
Roots annual; stem slender, finely retrorsely hirsute, low-climbing or trailing, 1°-2 1/2° long. Stipules ovate-lanceolate, 1/2"-1 1/2" long; leaflets lanceolate or linear-oblong, obtuse at the apex, rounded at the base, entire, 9"-18" long, 3"-5" wide; peduncles exceeding the leaves; flowers 2-6, capitate-umbellate, purplish, about 3' long; pod flat, linear, about 1' long and 2" wide, very pubescent; seeds purple, glabrous and shining at maturity, 1 1/2"-2" long.
50. V═GNA Savi, Mem. Phas. 3: 7. 1826.
Climbing or trailing herbaceous vines, or sometimes erect herbs, with pinnately 3-foliolate stipulate leaves, the leaflets broad. Flowers clustered at the ends of long axillary peduncles, yellowish or purplish, the rachis of the head or raceme knotty, the bracts and bractlets early deciduous. Calyx 5-toothed, or the 2 upper teeth united. Standard nearly orbicular, auricled at the base; wings shorter than the standard; keel about equalling the standard, slightly incurved. Stamens diadelphous (9 and 1). Ovary sessile; ovules numerous; style bearded along the inner side. Pod linear, nearly terete, 2-valved. [In honor of Domenic Vigni, a commentator on Theophrastus.]
Dolichos sinensis L. Cent. Pl. 2: 28. 1756. Dolichos Catjang L. Mant. 1: 269. 1767. Vigna Catjang Walp. Linnaea 13: 533. 1839. Vigna sinensis Endl.; Hassk. Pl. Jav. Rar. 386. 1848.
Annual, glabrous, or somewhat pubescent; stem twining or trailing, striate. Stipules ovate or ovate-lanceolate, acuminate, prolonged backward, 3"-10" long; petioles stout, often as long as the leaflets or longer; terminal leaflet rhombic-ovate, acute or blunt, 2'-6' long, often about as wide, long-stalked; lateral leaflets very obliquely ovate and inequilateral, about as large as the terminal one, short-stalked; flowers few near the knotty ends of the long peduncles, 8'-10" long; pod fleshy, 4-7' long, 3"-4" thick, nearly straight; seeds with a dark circle around the scar of attachment.
Escaped from cultivation, Missouri to Texas and Georgia. Native of Asia, and called chowley, towcok. Seeds edible. Black-eyed bean. July-Sept.
Vigna repŔns (L.) Kuntze, a smaller vine with much shorter pods, widely distributed in tropical America, has been found in ballast about New York.