GENUS I. 



MUSTARD FAMILY. 



2. Draba caroliniana Walt. Carolina 

 Whitlow-grass. Fig. 1998. 



Draba caroliniana Walt. Fl. Car. 174. 1788. 

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

 Draba caroliniana micrantha A. Gray, Man. Ed. 



5, 72. 1867. 

 Draba micrantha Nutt. ; T. & G. Fl. N. A. i : 109. 



1838. 



Winter-annual, the flowering scapes i'-s' 

 high from a short leafy stem. Leaves tufted, 

 obovate, 4"-io" long, obtuse, entire or rarely 

 with 3 or 4 teeth, pubescent with stiff stellate 

 hairs ; scapes nearly glabrous ; flowers white, 

 I $"-2" broad; petals entire, sometimes want- 

 ing in the later flowers; pedicels i"-2" long 

 in fruit, clustered near the summit of the 

 scape; pods linear, 4"-6" long, nearly i" 

 broad, glabrous or appressed-pubescent ; style 

 none. 



In sandy fields, eastern Massachusetts to south- 

 ern Ontario, Nebraska, Minnesota, Idaho, Georgia, Arkansas and Arizona. 



March-June. 



3. Draba cuneifolia Nutt. Wedge-leaved 

 Whitlow-grass. Fig. 1999. 



Draba cuneifolia Nutt. ; T. & G. Fl. N. A. i : 108. 

 1838. 



Winter-annual, stellate-pubescent all over, 

 4>'-8' high, branching and leafy below. Leaves 

 obovate, cuneate, or the lowest spatulate, i'-ii' 

 long, obtuse, dentate toward the summit; flow- 

 ering branches erect or ascending; flowers 

 white, 2" broad; petals emarginate, twice or 

 thrice the length of the calyx ; pedicels ascend- 

 ing or spreading, 2"-4" long in fruit; raceme 

 elongating; petals emarginate; pods linear- 

 oblong, obtuse, 4"-S" long, i" wide, minutely 

 hairy; style none. 



In fields, Kentucky to Kansas, south to Florida, 

 Texas and northern Mexico, west to southern 

 California. Feb.-April. 



4. Draba fladnizensis Wulf. White Arctic Whitlow- 

 grass. Fig. 2000. 



Draba fladnizensis Wulf. in J&cq, Misc. i : 147. 1778. 



Draba androsacea Wahl. Fl. Lapp. 174. 1812. 



Draba cormybosa R. Br. in Ross, Voy. App. 143. 1819. 



A low tufted arctic or alpine perennial. Leaves oblanceo- 

 late basal, rosulate, acutish, entire, stellate-pubescent or with 

 some simple hairs, ciliate or rarely nearly glabrous, 4"-8" 

 long; flowers whitish; scapes glabrous; pedicels ascending, 

 i"-2" long in fruit; raceme at length somewhat elongated; 

 pods oblong, glabrous, 2"-3" long, nearly i" wide, style 

 almost wanting. 



Labrador ; Mt. Albert, Gaspe, Quebec ; and through arctic 

 America, south in the higher Rocky Mountains to Colorado. Also 

 in arctic and alpine Europe and Asia. Summer. 



