106 LEGUMINOSJE. (PULSE FAMILY.) 



leaves bcncdlh mfl-<linrt<y and liwinj ; leaflets oval ; racemes many-flowered ; pods 

 very downy. S. Pennsylvania, Maryland, and southward. July. 



26. AMPIIICARP^A, Ell. HOG PEA-NUT. 



Flowers of 2 kinds, those of the racemes from the upper brandies perfect, but 

 seldom ripening fruit; those near the base and on creeping branches imperfect, 

 with the corolla none or rudimentary, and few free stamens, but fruitful. Calyx 

 about equally 4- (rarely 5-) toothed, with no bracelets. Keel and wing-petals 

 similar, nearly straight ; the standard partly folded round them. Stamens dia- 

 delphous. Pods of the upper flowers, when formed, somewhat scymetar-shapcd, 

 3-4-seedcd; of the lower, obovate or pear-shaped, fleshy, ripening usually but 

 one large seed, commonly subterranean, or concealed by decaving leaves. 

 Low and slender perennials ; the twining stems clothed with brownish hairs. 

 Leaves pinnately 3-foliolate : leaflets rhombic-ovate, stipellate. Flowers small, 

 in clustered or compound racemes, purplish. Bracts persistent, round, partly 

 clasping, striate, as well as the stipules. (Name from a/z<i, at loth cuds, and 

 Kapnos, fruit, in allusion to the two kinds of fruit, one at the summit, the other 

 at the base of the plant.) 



1. A. monoica, Nutt. Racemes nodding; bracts each supporting 2 or 

 more flowers, shorter than the pedicels ; subterranean pods hairy. Rich wood- 

 lands. Aug., Sept. A delicate vine. 



27. CL-ITdRIA, L. BUTTERFLY PEA. 



Calyx tubular, 5-toothcd. Standard much larger than the rest of the flower, 

 rounded, notched at the top, not spurred on "the back : keel small, shorter than 

 the wings. Stamens monadelphous below. Pod linear-oblong, flattish, knotty, 

 several-seeded, pointed with the base of the style, the valves nerveless. Erect 

 or twining perennials, with mostly pinnately 3-foliolate stipellate leaves, and 

 very large flowers. Peduncles 1 -3-flowered: bractlets opposite, striate. (Deri- 

 vation obscure.) 



1. C. Mariaira, L. Smooth; leaflets oblong-ovate or ovate-lanceolate ; 

 stipules and bracts awl-shaped; peduncles short; 1 -3-flowercd. Dry banks, 

 Long Island to Virginia and southward. July. Low, ascending or twining; 

 the showy pale-blue flowers 2' long. 



28. CENTROSEMA, DC. SPURRED BUTTERFLY PEA. 



Calyx short, 5-clcft. Corolla, &c. much as in Clitoria, but the standard with 

 n spur-shaped projection on the back. Pod long and linear, flat, pointed with 

 the awl-shaped style, many-seeded, thickened at the edges, the valves marked 

 with a raised line on each side next the margin. Twining perennials, with 3- 

 foliolatr stipdlatc leaves and large showy flowers. Stipules, bracts, and bract- 

 lets striate, the hit rr longer than the calyx. (Name from Kevrpov, a spur, and 

 the 8ltinrl,ir<l.) 



1. C. Virguiir&iiiBill, Beiith. Rather rough with minute hairs ; leaflets 



