BRASSICA SINAPIS. 95 



"but more intense than those of water-cress. It is chiefly used as a stimu- 

 lating condiment. Externally the bruised root, or more frequently the 

 leaves are used as a counterirritant. 



The acrid principles of these plants appear, clinically, to be eliminated 

 by the kidneys, and hence, incidentally, they produce a decided diuretic 

 effect. The lu-ine is not only increased in quantit}-, but partakes also of 

 the acrid character of the plant employed. In one case that came under 

 the author's observation the individual, though in j^erfect health so far as 

 the genito-urinary tract was concerned, suffered extremely from vesical 

 pain and irritation for hours after using horseradish as a condiment. 



BRASSICA.— SiNAPis. 



Character of the Genus. — Pod linear, cylindrical or nearly so, smooth 

 or with stiff hairs, more or less beaked at the top, the beak consisting of 

 the persistent style alone, or including a portion of the pod and a single 

 seed. Seeds globose, in a single row ; the cotyledons folded longitudi- 

 nally over the radicle. 



Annual or biennial herbs, smooth or bristly, the lower leaves generally 

 deepl}^ pinnate or lyrate, the uj^per sometimes entire. Flowers yellow, in 

 axillary and terminal racemes. 



No plants of this genus are indigenous to North America, but several 

 foreign species have become naturalized, the most important of which are 

 described below. 



Brassica alba Boissier {Sinapis alba Liuue). — Wldte 3Iustard. 



Description. — Flowers rather large, about one-half inch in diameter. 

 Pods three-fourths to one inch long on divergent ascending pedicels, more 

 than half the length occupied by the stout, flattened, often curved, 1-seeded 

 Leak ; the valves and lower part of the beak covered with stiif, bristly hairs. 

 Stem 1 to 2 feet high, smooth or with stiff hairs. Leaves pinnately lobed 

 or divided, the lobes ovate or oblong, coarsely toothed, the terminal one 

 largest. 



Habitat. — Introduced from Eui'ope and sparingly naturalized in culti- 

 Tated grounds. 



Brassica nigra Koch [Sinapis vigra Linne). — Black Mustard. 



Description. — Flowers smaller than in white mustard. Pods about one- 

 half inch long, on short, appressed pedicels, smooth, slightly conical at the 

 base, the apex tipped with the short, persistent style. Stem 2 to 3 feet 

 high, erect, freely branched. Lower leaves deeply divided, with one large 

 ovate or oblong terminal lobe and smaller lateral ones ; upjDcr leaves often 

 entire. 



Habitat. — Introduced from Europe. Better established than white mus- 

 tard. 



Part Used. — The seed. Official name : Sinapis alba — white mustard ; 

 Sinapis nigra — black mustard. — United States Pharmacopoeia. 



