LEGUMINOSAE (PEA FAMILY) 277 



tent: pubescence of the calyx more or less villous, spreading: pods 8-seeded. 

 Western Wyoming to Nevada and Washington. 



4. LOTUS L. TREFOIL 



Herbaceous. Leaves (in ours) 1-5-foliolate; stipules minute and gland-like. 

 Flowers in axillary umbels, or solitary. Calyx-teeth nearly equal, usually 

 shorter than the tube. Petals free from the stamens, nearly equal, yellow or 

 ochroleucous, or turning reddish ; claw of the standard usually remote from the 

 others; keel somewhat incurved. Stamens diadelphous. Pod linear, sessile, 

 partitioned between the seeds. 



Annual . . . . . . . . . . . . 1. L. americanus. 



Perennial 2. L. Wrightii. 



1. Lotus americanus (Nutt.) Bisch. Litt. Ber. Linnaea 14: 132. 1840. 

 Annual; more or less silky-villous or sometimes glabrous: leaves nearly ses- 

 sile; leaflets 3 (or 1, rarely 4), varying from ovate to lanceolate: peduncles 

 exceeding the leaves, one-flowered: calyx-teeth linear, much longer than the 

 tube, about equaling the corolla: keel attenuated upward, falcate, mostly 

 acute. Hosackia Purshiana. Across the continent; infrequent in our range. 



2. Lotus Wrightii (Gray) Greene, Pitt. 2: 143. 1890. Perennial; ashy- 

 puberulent, bushy-branched, very leafy: leaflets 3-5, apparently palmate and 

 sessile, the lowest oblong, the rest filiform-linear: peduncles short, rarely 

 equaling the leaf, 1-2-flowered: calyx-teeth setaceous-subulate, about equal- 

 ing the tube: keel not falcately-attenuate, mostly very obtuse. S. W. Col- 

 orado, New Mexico, and Arizona. 



6. MELILOTUS Tourn. MELILOT. SWEET CLOVER 



Annual or biennial herbs, with pinnately 3-foliolate leaves, usually serru- 

 te leaflets, small yellow or white flowers in slender axillary pedunculate 

 cemes, and an ovoid coriaceous wrinkled pod which is 1 or 2-seeded and 

 scarcely dehiscent. 



1. Melilotus alba Desv. in Lam. Encycl. 4: 63. 1797. Erect, 1-2 m. high, 

 branching: leaflets oblong, truncate, emarginate, or rounded at apex, 1-2 cm. 

 long: flowers white in slender racemes 5-10 cm. long, often 1-sided: pod 

 ovoid, glabrous. WHITE SWEET CLOVER. Naturalized from Europe; spar- 

 ingly grown for forage, and spreading as a weed. 



2. Melilotus officinalis (L.) Lam. Fl. Fr. 2: 594. 1778. Resembling the 

 preceding: leaves with rounded serrate apex: flowers yellow: pod subpubescent, 

 reticulate-veined. YELLOW SWEET CLOVER. Adventive from Europe ; in waste 

 grounds. 



6. MEDIC AGO L. ALFALFA. LUCERNE. MEDIC 



Annual or perennial herbs, with pinnately 3-foliolate leaves, toothed leaf- 

 lets, small flowers in spike-like racemes, and curved or coiled 1-few-seeded pods. 



1. Medicago sativa L. Sp. PI. 778. 1753. Upright and smooth perennial: 

 leaflets obovate-oblong: flowers purple, racemed: pod spirally twisted. An 

 extensively cultivated forage plant, peculiarly adapted to our range, and of 

 the highest value because of its quality and productiveness. 



7. TRIFOLIUM L. CLOVER 



Herbs, often tufted or diffuse, with palmately 3-foliolate leaves, or rarely 

 pinnately 3-5-foliolate. Stipules adnate to the petiole. Flowers usually capi- 

 tate, the heads sometimes elongated and spike-like. Calyx persistent, with 

 slender bristle-form teeth. Corolla persistent, united with the stamens. 

 Pods small, membranous, indehiscent, often included in the calyx. 



