Genus io. 



PEA FAMILY. 



351 



I. Medicago sativa L. Purple Medic. Alfalfa. 



Lucerne. Burgundy, Chilian or Brazilian 



Clover. Snail Clover. Fig. 2468. 



Medicago sativa L. Sp. PI. 778. 1753. 



Perennial, much branched, decumbent or ascending, 

 l°-i4° high, the young shoots and leaves with some 

 scattered hairs, glabrous when mature. Leaves petioled ; 

 leaflets oblanceolate or obovate, 2"-i2" long, dentate, 

 especially to\^ard the apex, obtuse, truncate or emargi- 

 nate and often mucronate, narrowed or cuneate at the 

 base ; stipules entire ; peduncles i'-2' long, bearing a 

 dense short raceme of violet or blue flowers; petals 

 about 3" long; pod pubescent, twisted into 2 or 3 spires. 



In fields and waste places, New England and Ontario to 

 Minnesota, south to Virginia and Kansas. Much cultivated 

 for fodder in the southern and western States. Introduced 

 from Europe. Great or Spanish trefoil. Holy-hay. Sainfoin. 

 Summer. 



Medicago falcata L., similar to this, but with yellow flowers and nearly flat, scarcely coiled 

 pods, is occa_sionally found in waste places. Native of Europe. 



2. Medicago lupulina L. Black or Hop Medic. 

 Blackseed. Hop Clover. Nonesuch. Fig. 2469. 



Medicago lupulina L. Sp. PI. 779. 1753. 



Annual, pubescent, branched at the base, the branches 

 decumbent and spreading, often i°-2° long; leaves pe- 

 tioled; leaflets obovate, oval or nearly orbicular, variable 

 in size, sometimes 6"-8" long, denticulate or crenulate, 

 obtuse, mucronate or emarginate, narrowed or rounded at 

 the base ; stipules ovate or lanceolate, dentate ; peduncles 

 i'-3' long; head oblong or cylindric, dense, 2"-io" long; 

 flowers bright yellow, about i" long; pods nearly glabrous, 

 black when ripe, curved into a partial spire, strongly 

 veined, i-seeded. 



In fields and waste places, common throughout our area, 

 except the extreme north, and widely distributed as a weed in 

 all temperate regions. Native of Europe and Asia. Black or 

 melilot-trefoil. Black-grass. Black-nonesuch, natural grass, 

 horned clover, shamroclc, sainfoin. March-Dec. 



3. Medicago hispida Gaertn. Toothed 

 Medic. Bur Clover. Fig. 2470. 



Medicago hispida Gaertn. Fr. & Sem. 2: 349. 1791. 

 Medicago denticulata Willd. Sp. Ph 3: 1414. 1803. 



Annual, branched at the base, the branches 

 spreading or ascending, glabrous or with a few 

 appressed hairs. Leaves petioled ; leaflets obovate, 

 rounded, emarginate or obcordate, cuneate, crenu- 

 late, s"-8" long; stipules dentate; flowers few, 

 yellow, i" long, in small, peduncled heads ; pod 

 several seeded, spirally twisted, the 2 or 3 coils 

 flat and rather loose, elegantly reticulated with 

 elevated veins, the thin edge armed with i or 2 

 rows of curved prickles and not furrowed. 



In waste places and in ballast about the seaports. 

 Nova Scotia to Pennsylvania, Florida, Nebraska, 

 Texas and also on the Pacific Coast. Bermuda. Fugi- 

 tive or adventive from Europe. Native also of Asia 

 and widely distributed as a weed. Summer. 



