PULSE FAMILY 135 
2. M. officinalis Willd. Yettow Swen Cover. A stout, upright, 
branching herb, 2-4 ft. high, looking much like the preceding species, 
but coarser. Flowers yellow. Waste ground and roadsides. Natu- 
ralized from Europe. 
XIV. MEDICAGO L. 
Annual or perennial herbs. Leaves petioled, of 3 toothed 
leaflets. Flowers in-terminal and axillary spikes or racemes. 
Calyx 5-toothed, the teeth short and slender. Standard 
oblong, much longer than the wings or keel. Stamens 10, 
diadelphous. Ovary sessile. Pod 1-several-seeded, coiled, 
not splitting open, often spiny.* . 
1. M. sativa L. Atraura. Perennial. Stems erect, branching, 
downy when young, becoming smooth with age, 2-3 ft. high. Leaves 
short-petioled ; leaflets obovate, sharply dentate towards the apex, 
obtuse or sometimes notched or mucronate; stipules lanceolate, entire. 
Flowers blue, small, in rather close spikes. Pods downy, coiled, few- 
seeded. Introduced from Europe, and cultivated for hay and pasture.* 
2. M. lupulina L. Brack Mepicx, Nonesucu. An annual or 
biennial, much-branched, reclining herb, with stems 6-20 in. long. 
Leaves very short-petioled ; leaflets obovate, acute, 1-3 in.long, toothed 
near the tip. Flowers small, yellow, in short spikes. Pods very small, 
l-seeded, kidney-shaped, black. Roadsides and waste ground, adven- 
tive from Europe. 
XV. PSORALEA L. 
Perennial herbs; whole plant glandular-dotted. Leaves of 
3-5 leaflets ; stipules united with the petioles. Flowers in axil- 
lary or terminal spikes or racemes. Calyx 5-cleft, the lobes 
nearly equal. Standard ovate or orbicular; keel .incurved, 
obtuse. Stamens monadelphous or diadelphous, 5 of the anthers 
often undeveloped. Ovary nearly sessile. Pod included in the 
calyx, often wrinkled, remaining closed, 1-seeded.* 
1. P. pedunculata Vail. Samson’s SnakERooT. Stem erect, slen- 
der, branching above, downy, 1-2 ft. high. Leaves of 3 leaflets; 
petioles shorter than the leaflets; stipules awl-shaped; leaflets ellip- 
tical or oblong-lanceolate, sparingly glandular-dotted, the terminal 
one stalked. Loosely flowered spikes axillary and terminal, on pedun- 
cles much longer than the leaves. Flowers blue or purple, about 4 in. 
long. Pod compressed-globose, wrinkled transversely. Dry soil.* 
2. P. tenuiflora Pursh. Upright, slender, bushy and branching, 
2-4 ft. high, covered when young with a fine grayish down. Leaves 
