PEA FAMILY 527 



racemose (raceme sometimes 1-flowered), perfect. Calyx obliquely campanu- 

 late, gibbous at the base, its teeth nearly equal, or the upper shorter. Banner 

 obovate, emarginate, clawed; wings obhquely oblong, adherent to the shorter 

 curved keel. Stamens diadelphous (9 and 1), monadelphous below; tube usually 

 truncate at the apex. Style curved, flattened, hairy along its inner side. Le- 

 gumes linear, more or less flattened, dehiscent, 2-valved. Seeds usually several. 



Corolla purple. 



Stem winged; leaflets linear, lanceolate, or oblong; flowers about 15 mm. long. 



1. L. palustris. 

 Stem wingless. * 



Racemes l-flowered. 11. L. Torreyi. 



Racemes several- to many-flowered. 



Tendrils much reduced; stem mostly erect. 



Leaflets 1 or 2 pairs; fldwers 8-10 mm. long. 



Leaflets narrowly linear. 2. L, Sandbergi. 



Leaflets oval or oblong. 3. L. bijugatus. 



Leaflets 3 or 6 pairs; flowers 20—25 mm. long. 



Plant glabrous or nearly so. 4. L. ornatiis. 



Plant decidedly villous-pubescent. 5. L. incanus. 



Tendrils usually well developed; plant more or less climbing. 

 Corolla less than 18 mm. long. 



Leaflets linear to oblong-elliptic, thick, veiny. 



Leaflets oblong-elliptic. 6. L. coreaceus. 



Leaflets linear. 7. L. graminifolius. 



Leaflets broadly oval or ovate. 



Tendrils usually 3-cleft; leaflets moderately firm, strongly veined. 

 Stipules large, often half as long as the small. 1-3 cm. long leaf- 

 lets. 8. L. Schaffneri. 

 Stipules very small m comparison with the large 2—7 cm. long 

 leaflets. 9. L. venosus. 

 Tendrils simple; leaflets not strongly veined. 10. L. Nuttallii, 



Corolla 2 cm. long or more. 



Stipules large and broad, about half as long as the leaflets. 

 Leaflets not linear. 



Leaflets rounded-oval, obtuse or roimded and mucronate at 



the apex. 12. L. utahensis. 



Leaflets elliptic, acute at both ends, cuspidate at the apex. 



13. L. pauciflorus. 

 Leaflets narrowly linear. 14. L. tenuior. 



Stipules narrow, less than half as long as the leaflets. 



Leaflets elliptic to oval. 15. L. decaphyllus. 



Leaflets linear-oblong or oblanceolate. 16. L. brachycalyx. 



Corolla w^hite or yellowish. 

 Tendrils well developed. 



Stipules lazge and broad, often half as long as the leaflets; corolla about 15 mm. 



long. 17. L. ochroleucus. 



Stipules smaller, much less than half as long as the leaflets; corolla about 20 mm. 

 long. 18. L. laeiivirens. 



Tendrils reduced; stipules narrow and small. 

 Corolla about 15-20 mm. long. 



Leaflets ovate or oval or obovate. 19. L. obovatus. 



Leaflets linear or lance-linear. 4. L. ornatus. 



Corolla 10-15 mm. long. 



Leaflets oval. 20. L. leucanlhus. 



Leaflets linear, 21. L. arizonicus, 



1. L. palustris L, Stem glabrous or nearly so, 3-6 dm. high; leaflets 2^ 

 pairs, 2.5-6 cm. long; tendrils usually branched; inflorescence 7-15 cm. long, 

 2-6-flowered; corolla purple, 12-15 mm. long; pod linear, 4-5 cm. long. Wet 

 places: Lab.— N.Y.— S.D.- — Ore.— Alaska; Eurasia. Plain — Suhmont, My- 

 Au. 



2. L. Sandbergi (White) Howell. Stem 2-3 dm. high, angled, glabrous, 

 erect; leaflets 5-10 cm. long, 2-4 mm. wide, glabrous; inflorescence 2-5 mm. long, 



1-3-flowered; corolla purphsh, about 1 cm. long, L. bijugatus Sandbergi White. 



Hillsides and copses: Ida. — Wash. Submont. My-Je. 



3. L. bijugatus White, Stem erect or decumbent at the base, 2-3 dm. 

 high, glabrous; leaflets thin, 2-5 cm. long, 6-12 mm. wide, mucronate; inflores- 

 cence 2-5 cm. long, 1-2-flowered; corolla purplish, 8-10 mm. long; pod 6-seeded. 

 Hillsides and rocky ground: Mont. — Ida. — Wash. Submont Je. 



4. L. omatus Nutt. Stem erect, glabrous or nearly so, 2-4 dm. high; leaf- 

 lets linear or lance-linear, 1.5-4 cm. long, 3-5 mm. wide, glabrous; peduncles 



