LEGUMINOS^E. 83 



Dry soils, pine barrens, &c; Southern part of the State. July, Aug. Sternt 

 prostrate or climbing. Leaflets about 1 inch long, % as wide. Flowers about half 

 at long as in the last. 



9. CENTROSEMA. DC 



Gr. kcnli'on, a spur, and sema, the standard. 



Calyx tubular, 5-toothed; the teeth much shorter than 

 the tube. Standard very large, with a spur-shaped projec- 

 tion on the back, notched at the top. Keel small, shorter 

 than the wings, incurved, acute, on long claws. Style 

 dilated at the apex, longitudinally bearded. Legume linear- 

 oblong, flat, pointed with the awl-shaped style, many- 

 seeded. — Twilling perennials, with p innately 3 to o-foliate 

 leaves, and large showy flowers. 



1. C. VlRGlNlANA, Benth. Spurred Butterfly Pea. 



Rather roughish with minute hairs; stem twining; leaflets varying from oblong- 

 ovate to linear, very veiny, shining; peduncles 1 to 4-flowcred; calyx about as long 

 as the lanceolate bracts, teeth lineav-awl-shaped ; legume linear, compressed. 



Sandy dry soils. July. Stipules, bracts, and bractlets striate, the latter longer 

 thau the calyx. Flowers large, purple, 1 to 2 inches long. Pods straight and 

 narrow, 4 to 5 inches long, Chickened at the edges, the valves marked with a line 

 on each side next the margin. 



10. AMPHICARPA. Ell. 



Gr. amphi, around, karpos, fruit; in reference to the ovary at base, sheathed. 



Calyx tubular, companulate, 4 (rarely 5) toothed with 

 nearly equal segments, with no bractlets. Keel and wing- 

 petals similar, nearly straight, the standard partly folded 

 round them. Stigma capitate. Ovary on a sheathed stipe. 

 Legume of the upper flowers flat, 2 to 4-seeded. — Low 

 slender twining perennial*, with piunately trifoliate leaves, 

 and 2 hinds of flowers, the upper ones perfect hut seldom 

 ripening fruit ; lower ones apetalous and fruitful. 



A. MOXOICA. Nutt. Hog Pea-nut. 



Stem hairy; leaflets ovate, acute, smooth; raceme of the stem with nodding, 

 pendulous petaliferous (generally barren) flowers; Lracts shorter than the pedicels; 

 calyx teeth short and broad. 



Rich woodlands. July — Sept. A delicate slender herb, with pale-purplish or 

 whitish flowers. Legume of the stem smootish, with 3 to 4 dark-purple seeds. 

 Radical legumes hairy, often very numerous, obovate or pear-shaped, fleshy, 

 repining usually but one large seed. 



11. WISTARIA. Nutt. 



In memory of Casper Wistar, M. D., President of Am. Philo. Soc. 



Calyx bilabiate, upper lip emarginate, the lower one with 



