92 KEY AND FLORA 



The entire plant is very fragrant. The two species are 

 introduced. 



a. M. Ind'ica Allioni. Flowers yellow, common. 



b. M. al'ba Lam. Flowers white. Less common. 



VI. MEDICA'GO, Bur Clover, Alfalfa 



Leaves pinnately compound, of 3 leaflets. Flowers in small 

 clusters or racemes in the axils of the leaves. Legumes curved 

 or curled like a screw. The species are introduced and are 

 valuable as fodder. 



a. M. denticula'ta Willd. BUR CLOVER. . Annual, low, with stems 

 spreading on the ground, smooth throughout. Flowers small, 

 yellow. Pod coiled, armed with a double row of prickles. Common. 



b. M. sati'va L. Alfalfa, Lucerne. Perennial, erect, smooth. 

 Flowers violet in a close raceme. Pod spirally coiled, without 

 prickles. Usually escaped from cultivation. 



c. M. apicula'ta Willd. This is similar in appearance to M. den- 

 ticulata, but the pods have the margins rough with fine tubercles instead 

 of with hooked prickles, and the whole surface veiny. In some places 

 this is more common than M. denticulata. 



VII. HOSACK'IA (LOTUS) 



Stamens diadelphous (9 and 1). Petals with long claws, 

 free from the stamens. Leaves pinnately compound with 

 from 2 to many leaflets. Flowers solitary or in umbels, ses- 

 sile or on peduncles from the axils of the leaves. Legumes 

 linear, sessile, somewhat compressed between the seeds. 



a. H. Purshia'na Beath. Annual, erect or spreading loosely over 

 the ground, with numerous slender branches, soft woolly through- 

 out. Leaflets generally 3 on a linear rhachis. Flowers solitary, 

 salmon-color, axillary on slender peduncles which are longer than the 

 leaves, with a single leaflet below the flower. Legumes from 1 to 1 

 in. long. This is common, blooming in the summer and autumn. 

 Widely distributed. 



b. H. subpinna'ta T. & G. Stems low, spreading or erect, smooth 

 or woolly. Leaflets small, 3-5, on a dilated rhachis : stipules gland- 

 like. Flowers small, nearly or quite sessile in the leaf axils, ivithout 

 bracts. Pod in. or more in length with about 5 seeds. From 

 Santa Barbara to Washington, common,. 



