CRUCIFERAE. 171 



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, 24 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 Ti^Aj 

 glaucous, glabrous or sparingly pubescent below; stems usually several, 5-10 J-*"-? 

 cm. high; radical leaves oblanceolate, acute, with slender petioles; pods straight, \+-V <* 

 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. DENT ARIA. 



Perennial herbs with long fleshy rootstocks which have a 

 pleasant pungent taste; stems leafless below, with 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, 

 1-3 cm. long, their petioles often bulbiferous below; cauline leaves 3-parted, 

 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 woods. 



Dentaria macrocarpa Nutt. 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 subspecies, 

 based mainly on differences in leaf contour. Most frequent on the eastern 

 slope of the Cascade Mountains but occurring locally in the Willamette Valley. 



