66 MUSTARD FAMILY. 



■i- -i- Leaves (except upon the flower-stem) thin and green; flowers small 

 and bright yellow. 



8. Pe-Tsai, Bailey. Chinese Cabbage, . Pe-Tsai. Leaves repand- 

 sinuate or only rarely somewhat lyrate, smooth or very nearly so, the 

 petiole thick and broadly winged; root annual, fibrous; leaves form a 

 loose head, resembling Cos Lettuce. China. 



B. Rapa, Linn. Turnip. Leaves prominently lyrate or interrupted 

 below, hairy ; the root tuberous. 



* » Plant green or but slightly glaucous when in flower; leaves of the 

 flower-stem not prominently clasping ; flowers small and yellow. 



B. nigra, Koch. Black Mustard. Leaves somewhat hairy and divided ; 

 pods erect in the raceme or spike, smooth, short, 4-sided (the valves having 

 a strong midrib), and tipped with the short, empty, conical base of a 

 slender style; seeds dark brown, small, pungent. Cultivated and in 

 waste places. Eu. ® 



B. Alba, Boiss. White Mustard. Leaves all pinnatifid and rough- 

 hairy ; pods spreading in the raceme, bristly hairy, the lower part 

 thick and few-seeded; seeds large, pale brown. Run wild, from 

 Eu. ® 



B. Sinaplstrum, Boiss. Charlock. Pods knotty, nearly smooth, 

 fully one third comprised in a stout 2-edged beak which is either 

 empty or 1-seeded ; upper leaves barely toothed. Weed in grain fields. 

 Eu. ® 



21. CAPSELLA, SHEPHERD'S PURSE. (Name means a little pod.) 

 (Lessons', Figs. 402, 403.) ® 



C. Bursa-Pastdris, Moench. Common S. The commonest of weeds, in 

 waste places ,■ root-leaves pinnatifid or toothed, those of the stem sagit- 

 tate and partly clasping ; small white flowers followed by the triangular 

 and notched pods, in a long raceme. 



22. LEPlblTJM, PEPPERGRASS, CRESS. (Greek : little scale, from 

 the pods.) Our common species have incised or pinnatifid leaves, and 

 very small white or whitish flowers. ® 



* Plant green. 



1- Leaves large, clasping ; hairy. 



L. campGstre, Br., has run wild (from Eu.) eastward. Known by its 

 strict habit, entire or only toothed leaves, and ovate winged rough pod. 



*- *- Leaves small, tapering at base, the lower ones at length falling; 



smooth. 



L. Virgfnioum, Linn. Wild P. Cotyledons accumbent ; petals pres- 

 ent, and usually only 2 stamens ; the little pods scarcely margined at the 

 notched tops ; seeds flat. A common weed by roadsides. 



L. intermedium, Gray. Cotyledons incumbent as in the following ; 

 pod minutely wing-margined at top ; petals minute or 0. W. N. Y. and 

 N. 111., N. and W. in dry places. 



L. ruderale, Linn., introduced from Europe, is much less common, more 

 branched, with no petals, the smaller scarcely notched pods and turgid 

 seeds marginless. % # ^^ ^ glaueous 



L. sativum, Linn. Garden Cress. Cultivated as a salad plant, has 

 petals, and the larger ovate pods are winged and slightly notched at 

 the top ; leaves (except the very uppermost) compound or much divided. 

 Eu. 



