Rydberg : Rocky Mountain flora 557 



Arabis oblanceolata sp. nov. 



Perennial, somewhat branched at the base, 3 dm. or more 

 high ; basal leaves petioled, sparingly stellate-pubescent, 3- 10 

 cm. long ; blades oblanceolate, acute, entire ; stem-leaves sessile, 

 lanceolate, sagittate-auricled at the base ; sepals oblong, acute, 

 3-4 mm. long, white-hairy near the apex ; petals dark reddish- 

 purple, 7-8 mm. long, spatulate with a long claw; pedicels in 

 fruit ascending, about 1 2 mm. long ; pods ascending, about 5 cm. 

 long and 2 mm. wide, glabrous ; seeds in 2 rows ; style none. 



This is perhaps nearest related to A. Crandallii Robinson, but 

 is a larger plant, less stellate, with much larger basal leaves and 

 pods, and the flowers are much darker. It grows at an altitude of 

 about 3,000 m. 



Colorado: Valley Spur, 1901, Undenvood & Selby 454. 



Arabis Selbyi sp. nov. 



Perennial, with a basal rosette of leaves; basal leaves ob- 

 lanceolate, 5-10 cm. long, short-petioled, acute, sinuate-dentic- 

 ulate, green but stellate on both sides, not ciliate ; stems 4-5 

 dm. high, branched ; stem-leaves linear-lanceolate, sagittate at the 

 base ; racemes long and lax ; sepals linear, green, obtuse, about 

 3 mm. long, sparingly stellate ; petals red-purple, narrowly ob- 

 lanceolate, long-clawed ; fruiting pedicels 3-4 mm. long, di- 

 vergent ; pods divergent, about 3 cm. long and 2 mm. wide, 

 obtuse at both ends ; style obsolete ; seeds in 2 rows. 



This species is perhaps nearest related to A. ligtrifera and A. 

 brachycarpa. From the first it differs in the large, denticulate 

 basal leaves, the stouter branched stem and the narrow dark 

 petals. The latter has hispid ciliate as well as stellate leaves. 

 A. Selbyi grows in canons and neighboring meadows at an altitude 

 of 2,300-2,800 m. 



Colorado: West of Ouray, 1901, Underwood & Se/by 20J. 



Erysimum oblanceolatum sp. nov. 



Biennial ; stem 4-6 dm. high, strigose, rather simple ; leaves 

 narrowly oblanceolate, 5-12 cm. long, entire or sinuate dentate; 

 the lower petioled, sparingly strigose ; racemes elongated ; sepals 

 linear, about 6 mm. long, about equaling the claw of the light yel- 

 low petals ; blades of the latter broadly spatulate or almost orbi- 

 cular ; the whole length of the petals about I 5 mm., fruiting pedi- 

 cels about 8 mm. long, ascending or spreading ; pod tetragonal, 

 ascending, about 8 cm. long, almost straight, not twisted, about 

 1.5 mm. thick; style about I mm. long. 



