176 CRUCIFERAE. 



cauline leaves sessile, the others petioled; flowers yellow, 3 mm. broad; pods 

 pubescent, tapering from the base to the apex, 1-2 cm. long, erect on short 

 pedicels. 



A weed in waste places; native of Europe. 



Sisymbrium officinale leiocarpum DC. Pods glabrous. 

 A very common weed in waste ground. 



Sisymbrium altissimum L. Tumbling Mustard. Erect, much branched, 

 60-150 cm. tall, glabrous or sparsely hirsute with simple hairs; basal leaves 

 petioled, pinnatifid into linear or lanceolate entire or dentate lobes; upper 

 leaves reduced, sessile; flowers pale yellow, S mm. broad; pods spreading, 

 linear, 6-10 cm. long, on short stout pedicels. 



Introduced from Europe. Locally called " Jim Hill Mustard." 



229. BARBAREA. 



Somewhat succulent perennials; stems angled; leaves entire or 

 pinnatifid; flowers yellow, in racemes; pod linear, terete, or 

 somewhat 4-angled, tipped with the short slender style; seeds 

 flat, in 1 row. 



Pods 1-1.5 cm. long, the beak slender, 2-3 mm. long; upper- 

 most leaves rarely pinnatifid. B. barbarea. 



Pods 2-4 cm. long, the beak thick and short; uppermost leaves 

 pinnatifid. B. orthoceras. 



Barbarea barbarea brachycarpa (Rouy & Foucaud) Piper, n. comb. (B. 

 vulgaris brachycarpa Rouy & Foucaud). Perennial, glabrous; stems simple 

 or branched above, 30-60 cm. high; lower leaves pinnatifid, the terminal 

 segment oblong to orbicular, larger than the 2-4 lateral pairs; upper cauline 

 leaves obovate to oblong, coarsely toothed, or toward the base lobed; flowers 

 deep yellow; pods 1-1.5 cm. long, ascending to spreading, terete, the slender 

 beak 2-3 mm. long. 



Introduced from Europe; Seattle, Piper. 



Barbarea orthoceras dolichocarpa Fernald. Bitter Cress. Perennial, 

 glabrous; stems simple or branched above, 30—90 cm. high; lower leaves from 

 entire to pinnately cleft or divided, the terminal segment large, orbicular or 

 ovate, entire or nearly so; lateral segments 1-5 pairs, smaller, oblong, entire or 

 toothed; petioles short, auricled at base; upper cauline leaves obovate, clasp- 

 ing, the lower part pinnately-cleft ; raceme dense; petals yellow, 4 mm. long, 

 twice as long as the sepals; pods ascending or spreading, at length curved, 

 2-4 cm. long, beaked by the stout style; pedicels short and stout. 



In wet places, not common but clearly native. 



230. LESQUERELLA. 



Low annual or perennial herbs with stellate pubescence; 

 flowers usually yellow; sepals oblong or elliptical, rather short; 

 petals longer, spatulate to oblong-obovate, entire; stamens 6; 

 style slender; stigma entire or nearly so; pod a turgid sub-globose 

 silicle with a broad suborbicular partition, 2-celled, each cell 

 2-16-seeded. 



Lesquerella occidentalis Wats. Perennial, from a stout caudcx; herbage 

 canescent with fine appressed silvery pubescence; stems 10-30 cm. high, erect 

 or ascending; basal leaves oblanceolate, coarsely toothed; cauline spatulate, 



