180 CRUCIFERAE. 



pod orbicular to obovate, much flattened at right angles to the 

 partition, 2-winged at the summit, each valve with one acute 

 nerve forming a keel; seeds flattened, solitary in each cell. 



Cauline leaves clasping at base. L. draba. 



Cauline leaves not clasping at base. 



Apex of the pods bidentate, the valves reticulated. 



Teeth of pods widely divergent. L. oxycarpum. 



Teeth of pods not widely divergent. L. strictum. 



Apex of the pods merely emarginate, the valves not re- 

 ticulated. 

 Petals wanting or very minute ; pods puberulent. L. lasiocarpum. 



Petals present; pods usually glabrous. 



Basal leaves pinnately parted, pubescent. L. menziesii. 



Basal leaves dentate, glabrous. L. medium. 



Lepidium draba L. Perennials, 20-40 cm. high, the herbage pubescent; 

 leaves oval to oblong, obtuse, denticulate, the upper broadly auricled and 

 clasping at base; racemes short; pods ovate, subcordate at base, tipped with 

 the conspicuous style. 



Sparingly introduced from Europe; Victoria, British Columbia, Anderson. 



Lepidium oxycarpum T. & G. Annual, glabrous or nearly so; stems 

 branched from the base, slender, ascending, 10-15 cm. high; leaves narrow, 

 pinnately cleft with a few acute lobes, or entire; raceme loose; petals none; 

 pods glabrous, nearly orbicular, about 3 mm. broad, with the teeth short and 

 widely divergent. 



Vancouver Island, British Columbia, Macoun, and California; mostly in 

 saline soil. 



Lepidium strictum Rattan. Annual, the herbage finely pubescent; stems 

 branched, erect or ascending, 8-15 cm. high; leaves pinnately cleft into narrow 

 lobes; raceme crowded; petals none; pods ovate, glabrous, 2-2.5 mm. long, 

 the teeth short and subacute, not widely divergent. 



In saline soil, Cadboro Bay, Vancouver Island, Macoun; otherwise known 

 only from California and southwestern Oregon. 



Lepidium lasiocarpum Nutt. Annual, usually with several decumbent 

 stems; herbage pubescent; lower leaves pinnately parted, the obtuse segments 

 toothed or entire; petals wanting or minute; capsule lenticular, retuse, thinner 

 at apex, minutely pubescent. 



Rare, probably only introduced in our limits. 



Lepidium menziesii DC. Biennial, erect or sometimes decumbent, much 

 branched above, 30-90 cm. high; stems puberulent; lower leaves pinnately 

 parted, more or less hairy, petioled, the segments toothed or entire; upper 

 leaves incisely dentate to entire ; petals present ; stamens 2 or 4 ; pods lenticular, 

 retuse, glabrous, about 3 mm. broad, on longer spreading pedicels. 



Common on high sea beaches. 



Lepidium medium Greene. Much like L. menziesii but root annual; 

 leaves serrate-dentate, seldom lobed, glabrous; stamens usually 6, sometimes 

 only 2; pods glabrous or puberulent. 



In sandy soil, common in the interior but only occasional west of the Cas- 

 cade Mountains. 



237. THLASPI. 



Glabrous annual or perennial herbs; basal leaves entire or 

 toothed; cauline oblong, auricled and clasping; flowers white or 



