CRUCIFERAE. I?I 



entire or nearly so; flowers corymbose; petals white, 2 mm. long, as long as the 

 sepals; pods erect, narrowly linear, glabrous, about 2 cm. long, on stout gla- 

 brous pedicels. 



Mount Olympus, Flett. 



Arabis furcata Wats. Perennial from a branched rootstock; stems slender, 

 20-40 cm. high, glabrous; basal leaves oblong-ovate, entire or few-toothed, 

 3-5 cm. long, sparsely pubescent with forked hairs; cauline oblong to linear, 

 sessile; petals white, spatulate, 12-15 mm. long, twice as long as the calyx; pods 

 slender, erect or ascending, 2-4 cm. long, attenuate at the apex. 



On rocky bluffs in the gorge of the Columbia River. 



Arabis patula Graham. (A. columbiana Macoun.) Biennial or perennial, 

 somewhat pubescent below, glabrous above; basal leaves oblanceolate, entire 

 or few-toothed, finally stellate pubescent, the petioles ciliate; cauline lanceo- 

 late, subentire, sessile, sagittate at base; flowers purple to nearly white; pods 

 sharply reflexed, flattened, 4-6 cm. long; seeds in 2 rows. 



On rocks and gravel bars in the mountains at low altitudes; not common. 



Arabis drummondii Gray. Biennial, nearly glabrous and somewhat 

 glaucous; stems mostly simple, 30-90 cm. high; basal leaves spatulate, sparingly 

 dentate; cauline oblong to lanceolate, somewhat auriculate; pods erect or 

 ascending, 4-10 cm. long; seeds oblong, winged, in two indistinct rows. 



In rocky places in the mountains at low altitudes. 



Arabis lyallii Wats. Perennial from a branched base, green or somewhat 

 glaucous, glabrous or sparingly pubescent below; stems usually several, 5-10 

 cm. high; radical leaves oblanceolate, acute, with slender petioles; pods straight, 

 erect, 2-5 cm. long; valves 1-nerved below the middle and with some smaller 

 veins. 



Common in the mountains at 1500-2000 m. altitude. 



221. DENTARIA. 



Perennial herbs with long fleshy rootstocks which have a 

 pleasant pungent taste; stems leafless below, \vith 2 or 3 petioled 

 compound leaves about or above the middle; flowers white or 

 purple in a corymb or raceme; style elongated; pod lanceolate, 

 compressed parallel to the partition; seeds in 1 row, wingless. 



Basal leaves cordate-orbicular, crenately or sinuately lobed. D. tenella. 

 Basal leaves mostly parted or divided into 3-5 segments. D. macrocarpa. 



Dentaria tenella Pursh. Glabrous; rootstocks tuberiferous; stems 10-40 

 cm. high; basal leaves simple, cordate-orbicular, coarsely crenate or lobed, 

 13 cm. long, their petioles often bulbiferous below; cauline leaves 3-partcd, 

 the narrow segments entire, 1-4 cm. long; raceme short; petals rose-purple; 

 pods 2-3 cm. long, 2 mm. broad, tipped with a slender style and a 2-lobed 

 stigma. 



In moist \voods. 



Dentaria macrocarpa Xutt. Glabrous or slightly pubescent; rootstock 

 tuberiferous, the tubers subglobose, 1-2 cm. in diameter; basal leaves 3-5- 

 lobed, cleft or divided, the segments linear, entire or toothed; peduncle short; 

 flowers rose-purple; pods 3-5 cm. long, 2 mm. broad; stigma entire. 



A variable species of which several forms have been described as subsprc ies, 

 based mainly on differences in leaf contour. Most frequent on the ea>tern 

 slope of the Cascade Mountains but occurring locally in the Willamc t u \ alley. 



