31. LÁTHYRUS, Tourn. Vetchling. Everlasting Pea.
Style flattish, dilated and flattish (not grooved) above, hairy along the inner side (next the free stamen). Sheath of the filaments scarcely oblique at the apex. Otherwise nearly as in Vicia.—Our species are perennial and mostly smooth plants, the rhachis of the leaves in some not produced into a tendril. (Λάθυρος, a leguminous plant of Theophrastus.)
[*] Tendrils present; stipules large and broad; leaflets 3–5 pairs.
1. L. marítimus, Bigelow. (Beach Pea.) Stout (1° high or more); stipules broadly ovate and halberd-shaped, nearly as large as the leaflets, the lower lobe larger and usually coarsely toothed; leaflets thick, ovate-oblong (1–2´ long); peduncles a little shorter than the leaves, 6–10-flowered, flowers large (9´´ long), purple.—Seashore from N. J. and Oregon to the Arctic Sea; also on the Great Lakes. (Eu.)
2. L. ochroleùcus, Hook. Stem slender (1–3° high); stipules semi-cordate, half as large as the thin ovate leaflets; peduncles 7–10-flowered; flowers smaller, yellowish-white.—Hillsides, N. Eng. to Minn., Iowa, and westward.
[*][*] Tendrils present; stipules narrow, semi-sagittate, acuminate.
[+] Flowers purple; leaflets several pairs.
3. L. venòsus, Muhl. Stout, climbing, usually somewhat downy; stipules very small and mostly slender; leaflets 4–6 pairs, oblong ovate, mostly obtuse (about 2´ long); peduncles many-flowered; flowers 6–8´´ long.—Shady banks, Penn. to Ga., west to Kan. and Minn.
4. L. palústris, L. Slender, glabrous or somewhat pubescent; stem often winged; stipules lanceolate, sharp-pointed at both ends; leaflets 2–4 pairs, narrowly oblong to linear, acute (1–2´ long); peduncles 2–6-flowered; flowers 6´´ long.—Moist places, N. Scotia to N. J., and westward across the continent. (Eu.)
Var. myrtifòlius, Gray. Stipules usually broader and larger; leaflets ovate to oblong (1´ long or less).—Same range, and extending south to N. C.
[+][+] Flowers yellow; leaflets a single pair.
L. pratènsis, L. Low and straggling; leaflets narrowly lanceolate to linear, acute; peduncles several-flowered.—Spontaneous in Mass., N. Y., and Ont. (Nat. from Eu.)
[*][*][*] Tendrils usually wanting; low, mostly erect; stipules semi-sagittate; flowers very large, purple; pod stipitate in the calyx.
5. L. polymórphus, Nutt. Leaflets 3–6 pairs, narrowly oblong to linear, thick and strongly nerved, 1–2´ long; seeds with a narrow footstalk and short hilum.—Mo., Kan., and westward.
6. L. ornàtus, Nutt. Like the last, but leaflets always narrow, 3–12´´ long; seeds with a very broad footstalk and long hilum.—Kan. to Col. and Dak. Scarcely 1° high.
32. ÁPIOS, Boerhaave. Ground-nut. Wild Bean.
Calyx somewhat 2-lipped, the 2 lateral teeth being nearly obsolete, the upper very short, the lower one longest. Standard very broad, reflexed; the long scythe-shaped keel strongly incurved, at length coiled. Stamens diadelphous. Pod straight or slightly curved, linear, elongated, thickish, many-seeded.—A perennial herb (with some milky juice!), twining and climbing over bushes, and bearing edible tubers on underground shoots. Leaflets 3–7, ovate-lanceolate, obscurely stipellate. Flowers in dense and short, often branching racemes. (Name from ἄπιον, a pear, from the shape of the tubers.)
1. A. tuberòsa, Moench. Flowers brown-purple or chocolate-color, violet-scented.—Low grounds, N. Brunswick to Fla., west to Minn., Kan., and La.
33. PHASÈOLUS, Tourn. Kidney Bean.
Calyx 5-toothed or 5-cleft, the two upper teeth often higher united. Keel of the corolla, with the included stamens and style, spirally coiled. Stamens diadelphous. Style bearded along the upper side; stigma oblique or lateral. Pod scythe-shaped, several–many-seeded, tipped with the hardened base of the style. Seeds round-reniform, with very short hilum. Cotyledons thick and fleshy, rising out of the ground nearly unchanged in germination.—Twining herbs, with pinnately 3-foliolate stipellate leaves. Flowers racemose, produced in summer and autumn. (The ancient name of the Kidney Bean.)
1. P. perénnis, Walt. (Wild Bean.) Stem climbing high from a perennial root; leaflets roundish-ovate, short-pointed; flowers purple, handsome, but small; pods drooping, strongly curved, 4–5-seeded.—Copses, N. Eng. to Fla., west to Minn. and La.
34. STROPHOSTỲLES, Ell.
Keel of the corolla with the included stamens and style elongated, strongly incurved, not spirally coiled. Pod linear, terete or flattish, straight or nearly so. Seeds quadrate or oblong with truncate ends, mealy-pubescent or glabrate; hilum linear. Flowers few, sessile and capitate clustered on the mostly long peduncles. Otherwise as Phaseolus.—Stems prostrate or climbing, more or less retrorsely hairy. Stipules and bracts striate. (Name from στροφή, a turning, and στῦλος, a style.)
1. S. angulòsa, Ell. Annual; stems branched, 1–6° long; leaflets ovate to oblong-ovate (rarely linear-oblong), with a more or less prominent rounded lobe toward the base (the terminal 2-lobed), or some or all often entire, about 1´ (6–20´´) long; corolla greenish-white and purplish; pod terete, 2–3´ long by 3´´ wide, 4–8-seeded, nearly glabrous; seeds oblong, about 3´´ long, usually very pubescent. (Phaseolus diversifolius, Pers. P. helvolus, L.)—Sandy shores and river-banks; coast of Mass. and southward, along the Great Lakes to Minn., and south to Kan. and Tex.
Var. Missouriénsis, Watson in herb. Climbing high (10–30°); leaves often 3´ long, rhombic-ovate, rarely at all lobed; seeds 3–4´´ long.—River-bottoms near Independence, Mo.; nearly two months later. (F. Bush.)
2. S. pedunculàris, Ell. Stems more slender, from a perennial rootstock, 2–4° long; leaflets ovate to oblong-linear, rarely at all lobed, 1´ long or less; pod 1½–2´ long and scarcely 2´´ wide; seeds much smaller, 1½–2´´ long, short-oblong to quadrate. (Phaseolus helvolus, Man., etc., not L.)—Sandy ground, Long Island and N. J. to Fla., west to S. Ind., Ky., and La.
3. S. pauciflòrus, Watson in herb. Annual, slender, low-climbing, pubescent; leaflets oblong-lanceolate or ovate-oblong to linear, not lobed, 1´ long; pod pubescent, 1´ long, flattish; seeds as in the last, very finely mealy, soon glabrate. (Phaseolus pauciflorus, Benth.)—River-banks, Ind. to Minn., south to Miss. and Tex.
35. CENTROSÈMA, DC. Spurred Butterfly-Pea.
Calyx short, 5-cleft. Corolla, etc., much as in Clitoria, but the spreading standard with a spur-shaped projection on the back near the base; keel broad. Style bearded at the apex around the terminal stigma. 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-foliolate stipellate leaves, and large showy flowers. Stipules, bracts, and bractlets striate, the latter longer than the calyx. (Name from κέντρον, a spur, and σήμα, a standard.)
1. C. Virginiànum, Benth. Rather rough with minute hairs; leaflets varying from oblong-ovate to lanceolate and linear, very veiny, shining; peduncles 1–4-flowered; calyx-teeth linear-awl-shaped; corolla violet, 1´ long; pods straight, 4–5´ long.—Sandy woods, Md. to Fla. and Ark. (Trop. Am.)
36. CLITÒRIA, L. Butterfly-Pea.
Calyx tubular, 5-toothed. Standard much larger than the rest of the flower, erect, rounded, notched at the top, not spurred on the back; keel small, shorter than the wings, incurved, acute. Stamens monadelphous