Genus 35. 



PEA FAMILY. 



393 



I. Aeschynomene virginica (L.) B.S.P. Sensitive Joint Vetch. Fig. 2572. 



Hedysanun virginicum L. Sp. PI. 750. I753- 



Aeschynomene hispida Willd. Sp. PI. 3; ii6j. 1800. 



Aeschynomene virginica B.S.P. Prel. Cat. N. Y. 13. 

 1S88. 



Annual, herbaceous, branched, erect, rough-pubes- 

 cent or glabrate, 2-5 high. Stipules membranous, 

 ovate, acuminate, 3"-4" long, deciduous ; leaves short- 

 petioled; leaflets 25-55, oblong, linear-oblong or ob- 

 lanceolate, obtuse at the apex, narrowed or rounded 

 at the base, 3"-9" long; somewhat sensitive; flowers 

 few, racemose, reddish-yellow, about 5" long; petals 

 veined; pod linear, 1-22' long, 3" wide, sparingly 

 tuberculate or glabrous, of 5-10 nearly square easily 

 separable joints. 



River banks, southeastern Pennsylvania, southwestern 

 New Jersey to Florida, west to Louisiana and Mexico. 

 Jamaica. Called also bastard sensitive plant. Aug.- 

 Sept. 



36. STYLOSANTHES Sw. Prodr. Fl. Ind. Occ. io8. 1788. 



Perennial herbs, mainly with some villous or viscid pubescence, 3-foliolate leaves, and 

 yellow terminal or axillary spicate or capitate flow-ers. Calyx deciduous, its tube narrow, 

 its teeth membranous, the 4 upper ones more or less united. Petals and stamens inserted 

 at or near the summit of the tube; standard orbicular; wings oblong; keel curved, beaked. 

 Stamens monadelphous ; anthers alternately longer and shorter. Ovary nearly sessile ; ovules 

 2-3; style filiform. Pod sessile, flattened, 1-2-jointed, reticulate, dehiscent at the summit. 

 [Greek, column-flower, alluding to the column-like calyx-tube.] 



About 30 species, natives of warm and temperate regions. Besides the following, another 

 occurs in the southern States. Type species: Stylosanthes prociimbens Sw. 



Leaflets oblong-linear to oblanceolate ; floral bracts entire. 

 Leaflets elliptic to obovate ; floral bracts deeply cleft. 



1. S. bi flora. 



2. S, riparia. 



A very 

 hispwissima 



I. Stylosanthes biflora (L.) B.S.P. Pencil-flower. Fig. 2573. 



Trifoliiim biflorum L. Sp. PI. 773. 1753. 



Stylosanthes elatior Sw. Svensk. Acad. Handl. 1789: 296. 

 PI. 2. f. ->. 1789. 



Stylosanthes biflora B.S.P. Prel. Cat. X. Y. 13. 1888. 



Wiry, branched from the base and often also above, 

 stems ascending, erect or spreading, villous-pubescent 

 or glabrate. 6'-24' long. Stipules sheathing the stem, 

 linear-filiform above; leaves short-petioled ; leaflets 3, 

 oblong, linear-oblong or oblanceolate, acute or acutish 

 and mucronate at the apex, narrow^ed or cuneate at the 

 base, 6"-i8" long, i4"-2" wide, strongly veined, the 

 terminal one stalked ; upper bracts entire ; flowers few, 

 mainly terminal, sessile or nearly so, yellow, ciliate- 

 bracted, 3"-4" long; pod obovate or suborbicular. pubes- 

 cent, about 2" long, of i perfect and i abortive joint. 



In dry soil, southeastern New York to Florida, west to 

 Indiana Kansas. Tennessee. Louisiana and Texas. June- 

 Sept. 



hairy southern race, ranging north to Virginia and Missouri, is known as S. biflora 

 (Michx.) Pollard & Ball. 



