M. satìva, L. (Lucerne. Alfalfa.) Upright, smooth, perennial; leaflets obovate-oblong, toothed; flowers (purple) racemed; pods spirally twisted.—Cultivated for green fodder; spontaneous from Mass. to Minn. and Kan. (Adv. from Eu.)
M. lupulìna, L. (Black Medick. Nonesuch.) Procumbent, pubescent, annual; leaflets wedge-obovate, toothed at the apex; flowers in short spikes (yellow); pods kidney-form, 1-seeded.—Waste places, N. Eng. to Fla., west to Mich., Iowa, and Mo. (Adv. from Eu.)
M. maculàta, Willd. (Spotted Medick.) Spreading or procumbent annual, somewhat pubescent; leaflets obcordate, with a purple spot, minutely toothed; peduncles 3–5-flowered; flowers yellow; pods compactly spiral, of 2 or 3 turns, compressed, furrowed on the thick edge, and fringed with a double row of curved prickles.—N. Brunswick to Mass. (Adv. from Eu.)
M. denticulàta, Willd. Nearly glabrous; pods loosely spiral, deeply reticulated, and with a thin keeled edge; otherwise like the last, and with the same range. (Adv. from Eu.)
12. HOSÁCKIA, Douglas.
Calyx-teeth nearly equal. Petals free from the diadelphous stamens; standard ovate or roundish, its claw often remote from the others; wings obovate or oblong; keel incurved. Pod linear, compressed or somewhat terete, sessile, several-seeded.—Herbs, with pinnate leaves (in ours 1–3-foliolate, with gland-like stipules), and small yellow or reddish flowers in umbels (ours solitary) upon axillary leafy-bracteate peduncles. (Named for Dr. David Hosack, of New York.)
1. H. Purshiàna, Benth. Annual, more or less silky-villous or glabrous, often 1° high or more; leaves nearly sessile, the 1–3 leaflets ovate to lanceolate (3–9´´ long); peduncles often short, bracteate with a single leaflet.—N. C.; S. W. Minn. to Ark., and west to the Pacific. Very variable.
13. PSORÀLEA, L.
Calyx 5-cleft, persistent, the lower lobe longest. Stamens diadelphous or sometimes monadelphous. Pod seldom longer than the calyx, thick, often wrinkled, indehiscent, 1-seeded.—Perennial herbs, usually sprinkled all over or roughened (especially the calyx, pods, etc.) with glandular dots or points. Leaves mostly 3–5-foliolate. Flowers spiked or racemed, white or mostly blue-purplish. Root sometimes tuberous and farinaceous. (Name, ψωραλέος, scurfy, from the glands or dots.)
[*] Leaves pinnately 3-foliolate.