CRUCIFERAE. 



[VOL. II. 



5. Draba nivalis 1,11 j. Yellow Arctic 

 Whitlow-grass. (Fig. 1759.) 



Draba nivalislj\\. Vet. Akad. Handl. 1793: 208. 1793. 



Perennial by a short branched caudex; scapes 

 tufted, somewhat pubescent, slender, leafless or 

 sometimes bearing a small sessile leaf, \'-6, f 

 high. Basal leaves usually numerous, tufted, 

 oblanceolate or spatulate, 2 // -7 // long, entire, 

 acutish or acute at the apex, narrowed into a 

 short petiole, stellate-can escent, not ciliate, or 

 slightly so near the base; flowers yellow, about 

 2" broad; calyx pubescent; style short; pods ob- 

 long or linear-oblong, narrowed at both ends, 

 glabrous or but little pubescent, on ascending 

 pedicels i // ~3 // long. 



Labrador (according to Robinson), through arctic 

 America to Alaska, south in the Rocky Mountains 

 to Colorado, and in the Sierra Nevada to Nevada. 

 Also in northern Europe and Asia. Summer. 



6. Draba incana L,. Hoary or Twisted Whitlow-grass. 



Draba incana L. Sp. PI. 643. 1753. 

 Draba confusa Ehrh. Beitr. 7: 155. 1792. 



Perennial or biennial, erect, simple or somewhat 

 branched, leafy, stellate-pubescent throughout, 6'- 

 12' high. Leaves lanceolate, oblanceolate or ovate, 

 4 // -i2 // long, acutish or obtuse, dentate or nearly 

 entire; flowers white, i"-i#" broad; petals 

 notched, twice as long as the calyx; pods oblong or 

 lanceolate, acute, twisted when ripe, on short nearly 

 erect pedicels, densely pubescent or nearly glabrous; 

 style minute. 



In rocky places. Green Mountains: Gaspe, Quebec, 

 arctic America, to British Columbia, south in the Rocky 

 Mountains to Colorado. Also in arctic and alpine Eur- 

 ope and Asia. Called also Hunger-flower. Summer. 



Draba incana arabisans (Michx.) S. Wats. Proc. Am. 



Acad. 23: 260. 1888. 

 Draba arabisans Michx. Fl. Bor. Am. 2: 28. 1803. 



Stem branched below, bearing tufts of spatulate 

 narrow leaves; pods glabrous, twisted; style 1 A" long. 

 Northern New England and New York to Labrador, 

 west along the Great Lakes to Minnesota and Manitoba. 



(Fig. 1760.) 



7. Draba ramosissima Desv. Branching 

 Whitlow-grass. (Fig. 1761.) 



Draba ramosissima Desv. Journ. Bot. 3: 186. 1814. 



Erect, much branched below, 6"-i8' high, stel- 

 late-pubescent throughout, the branches bearing 

 tufts of leaves, the inflorescence corymboscly pan- 

 iculate. Lower leaves spatulate or oblanceolate, 

 i / -2 / long, acute, dentate with spreading teeth; 

 upper leaves oblong or ovate, similarly dentate; 

 branches of the panicle erect or ascending; flowers 

 white, 2 // -3 // broad; petals entire or erose, twice or 

 thrice the length of the sepals; pedicels spreading 

 or ascending, 3 // -4 // long in fruit; pods oblong or 

 lanceolate, hairy, 3 / '-4 // long, twisted; style slender, 

 j//_ 2 // long. 



Mountains of Virginia and Kentucky, south to North 

 Carolina and Tennessee. April-May. 



