SPECIES AND VARIETIES. 193 



deeply pinnatifid, with few lanceolate toothed lobes, the ter- 

 minal one 1-li inch long, the others often directed backwards 

 towards the stem, upper leaves sometimes undivided and 

 hastate ; flowers very small, yellow ; pods half an inch long, 

 tapering to the point, almost sessile, and closely pressed against 

 the axis in long, slender racemes, the midribs of the valves 

 prominent. Hedge Mustard. Waste places, by roadsides. 

 Fl. June, July. 



S. Irio: annual; stem a foot high or more, erect, hard, 

 glabrous ; leaves deeply pinriatifid or pinnate, the lobes or 

 segments lanceolate, more numerous and larger than in the 

 former; flowers small, yellow; pods 1J-2 inches long, form- 

 ing dense racemes. London Rocket. Waste places, chiefly 

 about London and other towns. Fl. July, August. 



** Leaves 2-3 times pinnate. 



S. Sophia : annual ; stem a foot high or more, erect, slender, 

 somewhat hoary with very short down; leaves divided into 

 numerous short linear segments; flowers small, yellow; pods 

 slender, glabrous, -f 1 inch long, forming loose erect racemes. 

 Flixweed. Waste places. Fl. July to September. 



(22) Nasturtium. WATER-CRESS. 

 * Flowers white. 



N. officinale : stem much branched, short and creeping, or 

 floating in shallow water; leaves pinnate, with distinct seg- 

 ments, the terminal one usually larger, ovate or orbicular; 

 flowers small, white, in short racemes ; pods 6-8 lines long, 

 on spreading pedicels, slightly curved upwards. The com- 

 mon edible Water-cress. Brooks and rivulets. Fl. all the 

 Summer. 



