104 MUSTARD FAMILY 



1. DRABA. 



Depressed Alpine and sub-alpine herbs, with short racemes 

 of small, white or yellow flowers, pubescent with short 

 branched hairs. Leaves entire or few-toothed. Pods short, 

 flattened parallel to the partition; seeds in 2 rows in each 

 cell, not margined or winged. 



Slender annual or biennial with a rosette of basal leaves... 1. D. stenoloba. 

 Compact dwarf perennials, densely leafy at base. 



Flowers yellow; pods twisted 2. D. lemmonh. 



Flowers yellowish; pods not twisted 3. D. glacialis. 



Flowers white 4. D. brewcri. 



1. D. stenoloba Ledeb. Stems erect from a leafy base, 



annual or biennial, 1 ft. or less 

 high, including the long raceme 

 of yellow flowers (fading to 

 white or pinkish). Leaves thin, 

 obovate or oblanceolate, acutish, 

 J4 to 3/4 in. long. Pods linear, 

 acute, glabrous, % to y 2 in. long. 

 —Moist soil, 6500 ft. alt. to tim- 

 ber-line. 



2. D. lemmdnii Wats. Stems 

 close and matted at the per- 

 ennial base, y 2 to 2 in. high in- 

 cluding the raceme of bright- 

 yellow flowers. Herbage green 

 or yellowish. Leaves densely 

 clustered, oblong with narrow base (spatulate), mostly very 

 blunt, not ribbed, % to Vz in. long. Pods oblong or broadly 

 lanceolate, more or less twisted, y A in. long. — "Summit ot Mt. 

 Lyell, at 13,000 ft." is given as the type locality of this spe- 

 cies, which also grows on Mt. Gibbs, Mt. Dana, etc. 



3. D. glacialis Adams. Branches very compact and leafy, 

 forming rounded cushion-like perennial plants, the flowering 

 stems yi to 3 in. high. Flowers yellowish. Herbage gray 

 with short hairs. Leaves linear, rigid, rather acute, ribbed by 

 the reflexed margins and prominent midnerve, mostly minute, 

 rarely y 2 in. long. Pods ovate or roundish, not twisted, *4 

 in. or less long. — Above timber-line on Mt. Dana, Unicorn 

 Ridge, etc. 



4. D. breweri Wats. Stems erect from a branching per- 

 ennial base, 1 to 4 in. high, including the raceme of small 

 white flowers. Herbage gray with a close pubescence. 

 Leaves mostly in a basal tuft but also scattered along the 



Draba stenoloba 



