CRUCIFERAE (MUSTARD FAMILY) 223 



the style: pedicels usually much longer than the silique. D. alpina possibly 

 or D. glacialis. Stony slopes, middle elevations; northern Colorado to Mon- 

 tana. 



13. Draba spectabilis Greene, Pitt. 4: 19. 1899. Green but more or less 

 pubescent with short branched hairs: stems few to many from the short 

 woody caudex, 2-4 dm. high, equally leafy to the middle: radical leaves ob- 

 ovate to oblanceolate, short-petiolate ; the cauline ovate, oblong, or lanceolate, 

 acute, entire or toothed, 1-3 cm. long: sepals subglabrous or hirsute: petals 

 large, yellow: siliques 8-12 mm. long, oblong, glabrous or nearly so, on spread- 

 ing pedicels of about equal length; the style prominent. (D. oxyloba Greene, 

 PI. Baker. 3: 6. 1901, seems to be a smaller form of this.) Southern Colorado 

 and New Mexico. 



14. Draba chrysantha Wats. Proc. Am. Acad. 17: 364. 1882. Perennial, 

 with leafy, decumbent or erect stems, 5-15 cm. high, from a branching root- 

 stock, sparingly pubescent with simple hairs : basal leaves narrowly oblanceo- 

 late, 3-4 cm. long, entire or few-toothed, subciliate; cauline oblanceolate to 

 lanceolate: raceme open; flowers yellow, on pedicels 4-12 mm. long: silique 

 glabrous, oblong, acute at each end, 8-10 mm. long, beaked by a short slender 

 style. [(?) D. graminea Greene, PI. Baker. 3: 5. 1901. ] Mostly alpine; New 

 Mexico to Montana. 



15. Draba cana Rydb. Bull. Torr. Bot. Club 29: 241. 1902. Perennial 

 with a taproot and short caespitose caudex, whole plant densely grayish stel- 

 late: stem 1-2 dm. high, often branched: basal leaves numerous, oblanceolate 

 or spatulate, 1-1.5 cm. long, entire or minutely but sharply toothed, densely 

 stellate; stem leaves lanceolate to ovate, about 1 cm. long: racemes many- 

 flowered; pedicels short, nearly erect, in fruit 2-3 mm. long; flowers small: 

 petals white, about 3 mm. long: silique linear-oblong, 6-8 mm. long, densely 

 pubescent; style about 5 mm. long. D. incana. Mountains of Colorado, far 

 north into British America. 



16. Draba streptocarpa Gray, Am. Journ. Sci. II. 33: 242. 1862. More or 

 less villous with long spreading mostly simple hairs: stems erect, 1 or more 

 from the base, 3-15 cm. high: leaves oblanceolate to lanceolate, mostly acute, 

 somewhat villous, 6-15 mm. long: calyx glabrous or villous: siliques lanceo- 

 late, acute, flattened, more or less twisted, nearly glabrous except on the 

 margins, 6-12 mm. long, on pedicels half as long; the short style slender. 

 (D. Bakeri Greene, PI. Baker. 3: 6. 1901.) Alpine or subalpine; from New 

 Mexico far into British America. 



17. Draba surculifera A. Xels. Bull. Torr. Bot. Club 26: 237. 1899. Per- 

 ennial: stems few to several, usually with some short leafy stolons at the 

 base, 2-4 dm. high, pubescent with some simple hairs and a closer branched 

 puberulence: basal leaves crowded, oblanceolate, subpetioled, 3-5 cm. long, 

 thin, glabrate or stellate-pubescent; cauline similar but ovate or lanceolate, 

 sessile by a broad base, sometimes toothed: petals obovate, narrowed to a 

 claw, twice as long as the sepals: silique lanceolate, finely pubescent, 8-12 mm. 

 long, flat, or sometimes twisted; the style 1 mm. long. Cliff sides in the moun- 

 tains; Wyoming. 



18. Draba Helleriana Greene, Pitt. 4: 17. 1899. Rather stout, erect, 

 branching, especially above, 2-4 dm. high: pubescence scanty, the hairs sub- 

 appressed and 2-4-rayed: leaves ovate-oblong, entire or toothed, sessile: 

 racemes few to many, short: sepals yellow, hirsutulous: petals golden-yellow: 

 siliques much longer than the pedicels, flattened, acute, nearly glabrous ex- 

 cept on the ciliolate margins. D. aurea and yar. stylosa. (D. neo-mexicana 

 Greene, 1. c. 20.) Middle elevations; extending into Colorado from New 

 Mexico. 



19. Draba luteola Greene, 1. c. 19. Perennial, 1-3 ^lm. high, cinereously 

 stellate-pubescent with some villous simple hairs: leaves ovate-lanceolate, 

 subacute, entire or serrulate: racemes few or several, often long: sepals thin, 

 yellowish-green, hirsute: petals yellow, obtuse: silique rough-puberulent, 

 tipped with a short slender style; pedicels shorter than the silique and dis- 

 tinctly villous. D. lutea. (D. uber A. Nels. Bot. Gaz. 34: 366. 1902; D. 



