6. P. digitàta, Nutt. More slender and less hoary, 1–2° high; leaflets linear-oblanceolate; bracts of the interrupted spike obcordate; calyx-lobes oblong, acute.—Central Kan. to Col. and Tex.
7. P. lanceolàta, Pursh. Glabrous or nearly so, yellowish green, densely punctate; leaflets 3, linear to oblanceolate; flowers small, in very short spikes; calyx 1´´ long, with short broad teeth.—Central Kan. to the Sask. and westward.
[*][*][*] Leaves palmately 5-foliolate; root tuberous; spike-like racemes dense.
8. P. esculénta, Pursh. Roughish hairy all over; stem stout (5–15´ high) and erect from a tuberous or turnip-shaped farinaceous root; leaflets obovate- or lanceolate-oblong; spikes oblong, long-peduncled; lobes of the calyx and bracts lanceolate, nearly equalling the corolla (½´ long).—High plains, Sask. to Wisc., Iowa, and Tex. June. The Pomme blanche, or Pomme de Prairie, of the voyageurs.
9. P. hypogæ̀a, Nutt. Tuber small; nearly acaulescent, hoary with appressed hairs; leaflets linear; spikes short-capitate, on peduncles ½–2´ long; calyx narrow, 3–6´´ long.—Central Kan. to Col. and Tex.
10. P. cuspidàta, Pursh. Stout, tall, from a deep-seated tuber, hoary with appressed hairs; leaflets usually broadly oblanceolate, obtuse; flowers large, the petals (6–8´´ long) exceeding the lanceolate-lobed calyx.—Central Kan. to Col. and Tex.
14. AMÓRPHA, L. False Indigo.
Calyx inversely conical, 5-toothed, persistent. Standard (the other petals entirely wanting!) wrapped around the stamens and style. Stamens 10, monadelphous at the very base, otherwise distinct. Pod oblong, longer than the calyx, 1–2-seeded, roughened, tardily dehiscent.—Shrubs, with odd-pinnate leaves; the leaflets marked with minute dots, usually stipellate, the midvein excurrent. Flowers violet or purple, crowded in clustered terminal spikes. (Name, ἄμορφος, deformed, from the absence of four of the petals.)
[*] Pods 1-seeded; leaflets small (½´ long or less), crowded.
1. A. canéscens, Nutt. (Lead-Plant.) Whitened with hoary down (1–3° high); leaflets 15–25 pairs, oblong-elliptical, becoming smoothish above; spikes usually clustered at the summit.—Sask. to Ind. and Tex., west to the Rocky Mts.; also eastward to Ga.
2. A. microphýlla, Pursh. Nearly glabrous throughout, 1° high or less; leaflets rather rigid; spikes usually solitary.—Sask. to Minn. and Iowa, west to the Rocky Mts.
[*][*] Pods 2-seeded; leaflets larger, scattered.
3. A. fruticòsa, L. (False Indigo.) A tall shrub, rather pubescent or smoothish, leaflets 8–12 pairs, oblong to broadly elliptical.—River-banks, S. Penn. to Fla., west to Sask., Tex., and the Rocky Mts. Very variable.
15. DÀLEA, L.
Calyx 5-cleft or toothed. Corolla imperfectly papilionaceous; petals all on claws; the standard heart-shaped, inserted in the bottom of the calyx; the keel and wings borne on the middle of the monadelphous sheath of filaments, which is cleft down one side. Stamens 10, rarely 9. Pod membranaceous, 1-seeded, indehiscent, enclosed in the persistent calyx.—Mostly herbs, more or less glandular-dotted, with minute stipules; the small flowers in terminal spikes or heads. (Named for Samuel Dale, an English botanist.)
[*] Glabrous; flowers white or rose-color; leaflets 4–20 pairs; annuals.
1. D. alopecuroìdes, Willd. Erect (1–2° high); leaflets 10–20 pairs, linear-oblong; flowers light rose-color or whitish, in cylindrical spikes; bracts ovate-lanceolate, acuminate, deciduous; calyx very villous, with long slender teeth.—Alluvial soil, Minn. to Ill. and Ala., west to the Rocky Mts.
2. D. laxiflòra, Pursh. Erect (1–4° high), branching; leaflets 3–5 pairs, linear, 2–3´´ long; spikes loosely-flowered; bracts conspicuous, persistent, almost orbicular and very obtuse; petals white; calyx densely villous, the long teeth beautifully plumose.—Iowa and Mo. to Tex., west to Col.
[*][*] Pubescent; leaflets 3–4 pairs; perennial herbs.
3. D. aùrea, Nutt. Stems erect and simple, 1–3° high; leaflets oblong-obovate to linear-oblong, more or less silky-pubescent; spikes solitary, oblong-ovate, very compact and densely silky; bracts short, rhombic-ovate; petals yellow.—On the plains, Mo. to Tex., and westward.
4. D. lanàta, Spreng. Very pubescent throughout, 1–2° high, branching; leaflets obovate to oblong-obovate, 2–3´´ long; spikes slender, rather loose, the obovate acute bracts equalling the small short-toothed calyx; petals short, purple.—Central Kan. to Tex., and westward.
16. PETALOSTÈMON, Michx. Prairie Clover.
Calyx 5-toothed. Corolla indistinctly papilionaceous; petals all on thread-shaped claws, 4 of them nearly similar and spreading, borne on the top of the monadelphous and cleft sheath of filaments, alternate with the 5 anthers; the fifth (standard) inserted in the bottom of the calyx, heart-shaped or oblong. Pod membranaceous, enclosed in the calyx, indehiscent, 1–2 seeded.—Chiefly perennial herbs, upright, glandular-dotted, with crowded odd-pinnate leaves, minute stipules, and small flowers in very dense terminal and peduncled heads or spikes. (Name combined of the two Greek words for petal and stamen, alluding to the peculiar union of these organs in this genus.)
1. P. violàceus, Michx. Smoothish; leaflets 5, narrowly linear; heads globose-ovate, or oblong-cylindrical when old; bracts pointed, not longer than the silky-hoary calyx; corolla rose-purple.—Dry prairies, Minn. to Ind. and Tex., west to the Rocky Mts. July.
2. P. cándidus, Michx. Smooth; leaflets 7–9, lanceolate or linear-oblong; heads oblong, when old cylindrical; bracts awned, longer than the nearly glabrous calyx; corolla white.—With n. 1.
3. P. villòsus, Nutt. Soft-downy or silky all over; leaflets 13–17, linear or oblong, small (4–5´´ long); spikes cylindrical (1–5´ long), short-peduncled, soft-villous; corolla rose-color.—Wisc. to Mo., west to the Rocky Mts.
4. P. foliòsus, Gray. Smooth, very leafy; leaflets 15–29, linear-oblong; spikes cylindrical, short-peduncled; bracts slender-awned from a lanceolate base, exceeding the glabrous calyx; petals rose-color.—River-banks, Ill. and Tenn.
5. P. multiflòrus, Nutt. Glabrous throughout, erect, branching; leaflets 3–9, linear to oblong; spikes globose, the subulate setaceous bracts much shorter than the acutely toothed calyx, petals white.—Kan. to Tex.
17. TEPHRÒSIA, Pers. Hoary Pea.
Calyx about equally 5-cleft. Standard roundish, usually silky outside, turned back, scarcely longer than the coherent wings and keel. Stamens monadelphous or diadelphous. Pod linear, flat, several seeded, 2-valved.—Hoary perennial herbs, with odd-pinnate leaves, and white or purplish racemed flowers. Leaflets mucronate, veiny. (Name from τεφρός, ash-colored or hoary.)
1. T. Virginiàna, Pers. (Goat's Rue. Catgut.) Silky-villous with whitish hairs when young; stem erect and simple (1–2° high), leafy to the top; leaflets 17–29, linear-oblong; flowers large and numerous, clustered in a terminal oblong dense raceme or panicle, yellowish-white marked with purple.—Dry sandy soil. June, July.—Roots long and slender, very tough.
2. T. spicàta, Torr. & Gray. Villous with rusty hairs; stems branched below, straggling or ascending (2° long), few-leaved; leaflets 9–15, obovate or oblong-wedge-shaped, often notched; flowers few, in a loose