604 FABACEAE 
7. MEDICAGO L. 
Herbs or shrubby plants, with erect or prostrate stems. Leaves alternate: blades 
pinnately 3-foliolate: leaflets commonly toothed by the prominent excurrent lateral nerves. 
Flowers perfect, in elongated or head-like peduncled racemes. Calyx pedicelled: lobes 
slender, nearly equal. Corolla yellow or violet: standard with an oblong or obovate 
nearly sessile blade: wings nearly oblong: keel obtuse, shorter than the wings. Stamens 
10, diadelphous, the one opposite the standard, distinct. Anthers all alike. Ovary sessile 
or short-stalked. Style subulate. Stigma oblique. Ovules numerous or rarely solitary. 
Pod curved or spirally coiled, often spiny, usually reticulated, indehiscent. MEDIC. 
Pods unarmed, 1-seeded. 1. M. lupulina. 
Pods prickle-armed, several-seeded. 
Pods loosely coiled, not furrowed on the edge between the prickles. 2. M. denticulata. 
Pods tightly coiled, furrowed on the edge between the prickles. 3. M. Arabica. 
1. Medicago lupulina L. Foliage strigillose. Stems branching at the base, the 
branches spreading, prostrate, 2-7 cm. long; leaflets 3, the blades obovate or rhomboidal, 
0.5-1.5 em. long, usually retuse and mucronate at the apex, denticulate, sessile or short- 
stalked : petioles variable in length : peduncles slender, 2-10 cm. long : racemes subglobose 
or ovoid in flower, oblong-cylindric in fruit : calyx-tube turbinate: corolla bright yellow, 
2-3 mm. long: pods spirally twisted, about 3 mm. long, black, reticulated, glabrous or 
nearly so, unarmed, 1-seeded. 
In waste places throughout North America except the extreme north. Spring to winter. Widely 
naturalized in temperate regions, from Europe and Asia. 
2. Medicago denticulàta Willd. Foliage glabrous or sparingly pubescent. Stems 
branched at the base, the branches radially spreading, ascending or procumbent, 1-4 dm. 
long : leaflets 3, the blades obovate, cuneate or oval, 0.5-1.5 cm. long, denticulate, rounded, 
retuse or notched at the apex: petioles variable in length: peduncles 0.5-2 cm. long: 
calyx often sparingly pubescent: corolla yellow, about 5 mm. long: pods loosely twisted 
into 2-3 coils, flat; 5-8 mm. broad, reticulated, the edges armed with 1-2 rows of curved 
prickles. 
In waste places, especially near seaports, Nova Scotia to Florida and Texas. Summer. Naturalized 
from Europe and Asia. 
3. Medicago Arábica All. Foliage glabrous or pubescent with a few spreading 
hairs. Stems branched at the base, the branches prostrate or ascending: leaflets 3, the 
blades broadly cuneate or obovate, 1-2.5 cm. long, denticulate, usually blotched in the 
center, rounded or notched at the apex: petioles commonly longer than the leaflets : 
peduncles 1-2 cm. long: calyx often sparingly pubescent : corolla yellow, about 5 mm. 
long: pods closely twisted into 3-4 coils, 6-9 mm. broad, reticulated, the edges arm 
with curved prickles. 
In waste places, New Brunswick to Georgia and Louisiana. Summer. Introduced from Europe. 
8. MELILOTUS Juss. 
Annual or biennial caulescent herbs, with fragrant herbage. Leaves alternate, with thin 
stipules: blades pinnately 3-foliolate : leaflets much longer than broad, the nerves excur- 
rent into teeth. Flowers perfect, in elongated narrow racemes. Calyx pedicelled : 
lobes 5, nearly equal. Corolla yellow or white, deciduous: petals free from the filaments : 
standard rather abruptly contracted at the base of the blade, nearly sessile: wings narrower 
than the standard, cohering with the shorter obtuse keel-petals. Stamens diadelphous. 
Ovary sessile or short-stalked. Style filiform. Stigma terminal. Ovules few. Pod 
straight, short and thick, often subglobose, indehiscent or nearly so. SWEET CLOVER. 
Corolla 2-2.5 mm. long. 1. M. Indien. 
Corolla 5-6 mm. long, M. inalis. 
Corolla yellow: standard and wing-petals about equal in length. 2. ML p.c 
Corolla white: standard surpassing the wing petals. RM 5 
Y à ? Stems 
1. Melilotus Indica (L.) All. Foliage minutely pubescent when young. 
erect or spreading, 2-7 dm. v sometimes enera PRE : Jeaflets 3, the blades a 
long, oval, cuneate or obovate, 0.5-2 cm. long, retuse to rounded at the apex, cipe ds 
racemes slender, 1-2 cm. long: calyx campanulate ; lobes longer or shorter than t at x 
which is scarious in the sinuses : corolla yellow, about 2-2.5 mm. long ; standard w 
blade 1-1.5 mm. broad : pods oval or subglobose, 2 mm. long, wrinkled. 
In waste places, about seaports, on the Atlantic and Pacific coasts and sometimes 
Introduced from Europe. Spring to fall. 
in the interior. 
