PEA FAMILY 529 



5-10 cm. long; racemes short, 3-5-flowered ; corolla purple, 2.5-3 cm. long; pod 

 4-5 cm. long. Plains and prairies: Neb. — N.M. — Ariz. Plain — Subrnont. 

 My-Jl. 



16. L. brachycalyx Rydb. Stem simple or slightly branched, 1.5-3 dm. 

 high, usually finely pubescent, sharply 4-angled; leaflets 2-5 pairs, linear-oblong 

 or oblanceolate, firm, strongly veined, finely pubescent, 1-3 cm. long, 2-8 mm. 

 wide; tendrils of the lower leaves reduced to mere tips; peduncles 5-10 cm. long; 

 raceme short, 2-6-flovvered; corolla purple, 2-2.5 cm. long; pod glabrous, 3-4 cm. 

 long. Mountains: Utah. SubmoriL — Moid. Je-Au. 



17. L. ochroleucus Hook. Stem 4-10 dm. high, terete, glabrous; leaflets 

 3-4 pairs, broadly oval or ovate, 2-5 cm. long, thin, glabrous, somewhat glaucous 

 beneath; pedimcles 2-5 cm. long; racemes 5-10-flowered; corolla ochroleucous, 

 about 15 mm. long; pod about 4 cm. long, glabrous. Woods and river banks: 

 Hudson Bay — Que.— N.J. — Wyo. — B.C. — Mack. Plain — Subrnont. My-Au. 



18. L. laetivirens Greene. Stem branched, cHmbing, 4-6 dm. high; leaf- 

 lets 3-5 pairs, oval or ovate, obtuse and mucronate, light green and glabrous, 

 2-5 cm. long, 1-2.5 cm. wide; peduncles about 5 cm. long; raceme short, 3-6- 

 flowered; corolla ochroleucous, about 2 cm. long; pod about 4 cm. long. Moun- 

 tains: Colo. Subtnont. — Mont. Je. 



19. L. obovatus (Torr.) White. Stem finely pubescent or glabrous, 2^ 

 dm. high; leaflets 2-4 pairs, ovate or oval, 2-5 cm. long, obtuse or acute, thin; 

 corolla white or nearly so, 15-20 mm. long; pod about 4 cm. long. L. nevadensis 

 S. Wats., in part. Mountains: Wash. — Ida. — Calif. Son. My-Je. 



20. L. leucanthus Rydb. Stem about 3 dm. high, angled, glabrous; 

 leaflets 2—4 pairs, elliptic, veiny, glaucous, acute, mucronate, 1-3 cm. long, 3-10 

 mm. wide; inflorescence short, in the axils of the middle leaves, 3-4 cm. long, 

 2-4-flowered; corolla white, about 15 mm. long. Open woods: Wyo. — N.M. 

 Mont. My-Jl. 



21. L. arizonicus Britton. Stem 2^ dm. high, glabrous; leaflets usually 

 2 pairs, glabrous or nearly so, narrowly linear, 3-8 cm. long, 2-10 mm. wide; 

 peduncles 2—1 cm. long; racemes 2-3-flowered; corolla white, 10-15 mm. long. 

 Open woods: Colo.— N.M. — Ariz. Mont. — Subalp. My-Jl. 



44. APIOS Moench. Ground-nut. 



Twining vines, with large tuberous roots. Leaves alternate, pinnate, with 

 small stipules. Flowers perfect, in racemes. Upper two calyx-teeth united, 

 the lateral ones very small, and the lowest one longer. Corolla red, purple, or 

 brown; banner reflexed; keel elongate, spirally twisted. Stamens diadelphous. 

 Style glabrous. Pod elongate, curved, flattened. 



1. A. Apios (L.) MacMiU. Stem 3-20 dm. long; leaflets 5-9, ovate to 

 lanceolate, 3-10 cm. long, acute or acuminate; calyx-tube 2-4 mm. long; corolla 

 brownish purple; banner with a broad blade, about 1 cm. long; pod linear, 6-12 

 cm. long. A. tubcrosa Moench. Thickets: N.B. — Fla. — Tex. — Colo. — Minn. 

 Plain — Subrnont. 



45. STROPHOSTYLES Ell. Wild Bean. 



Herbaceous vines, twining or trailing. Leaves alternate, pinnately 3-foliolate, 

 with stipules. Flowers perfect, in dense clusters on long axillary peduncles. 

 Calyx subequally 5-toothed, or the upper two teeth partially united. Corolla 

 white or purplish ; banner with a broad blade ; keel curved. Stamens diadelphous. 

 Style bearded, bent. Pod narrow, flat, straight or nearly so. Seeds truncate. 



1. S. pauciflora (Benth.) S. Wats. Annual; stem 3-10 dm. long; leaflets 

 linear to lanceolate, 1.5-3.5 cm. long, rarely sinuately lobed; pediuicles longer 

 than the leaves; calyx 1.5 mm. long; lobes subequal; corolla pale purple; pod 

 2-3 cm. long, strigose. Phaseolus pauciflorus Benth. River banks: Minn. — 

 Ind. — La. — Tex.- — Colo. Plain. 



