352 BRASSICACEAE 



Petals bright yellow; stem-leaves entire-margined. 



46. D. surculifera. 



Petals 3-4 mm. long, pale yellow; stem-leaves entire-mar- 

 gined. 47. D. aureiformis. 

 Leaves thick, the basal ones oblanceolate, 1-2 cm. long, the 



cauline lanceolate or oblong. 48. D. aurea. 



Stem decumbent. 



Leaves finely stellate; pods twisted. 49. D. decumbens. 



Leaves coarsely hairy, with branched hairs; pods not twisted. 



50. D. brachystylis. 



1. D. asprella Greene. Winter annual, scapose or nearly so; scapes 1 to 

 several, 5-10 cm. high, hirsute with branched hairs; leaves basal, rosulate, ob- 

 lanceolate, 2-3 cm. long, densely hairy; petals yellow, 4-5 mm. long; pod rather 

 turgid, 5 mm. long or more. Mountains: Ariz. -s Utah. My. 



2. D. micrantha Nutt. Annual; stems 5-10 cm. high, branched at the 

 base, more or less pubescent; leaves 5-15 mm. long, ovate or elliptic, entire, 

 stellate; petals shorter than the hairy sepals, or none, sometimes in the earlier 

 flowers 2.5-3 mm. long, 2-cleft at the apex; pedicels ascending; pod hispid, 6-12 

 mm. long, 4 mm. wide. D. caroliniana micrantha A. Grav. Dry plains: 111. 

 Tex. Ariz. Wash. Plain. Mr-Au. 



3. D. coloradensis Rydb. Annual, leafy below, often branched, 5-10 cm. 

 high; leaves obovate, entire, 1-2 cm. long, 0.5-1 cm. wide, subsessile, coarsely 

 hirsute; petals white, 3-3.5 mm. long, spatulate, emarginate; pods linear-oblong, 

 10-12 mm. long and nearly 2 mm. wide. Plains and hillsides: N.M. Colo. 

 S.D. Plain Submont. Ap-My. 



4. D. cuneifolia Nutt. Annual; stem 5-20 cm. high, branched; leaves 

 obovate or cuneate, 1-4 cm. long, usually coarsely toothed above the middle, 

 stellate; racemes elongate in fruit; petals white, 3-4 mm. long; pod 7-15 mm. 

 long, 2 mm. wide, rarely glabrate. Grassy places and plains: 111. Fla. Calif. 

 Ida. Plain. F-My. 



6. D. nemorosa L. Winter annuals; stem leafy, 0.5-3 dm. high, branched 

 below; leaves often more or less dentate; petals light yellow, 2-3 mm. long; 

 fruiting pedicels divaricate, 1-2 cm. long; pods oblong, 5-10 mm. long, 2 mm. 

 wide. Hills, prairies, and plains: Mich. -Colo. Nev. Ore. B.C.; Eurasia. 

 Plain Mont. Ap-Au. 



6. D. montana S. Wats. Winter annual; stem branched or simple, leafy, 

 1-2 dm. high; basal leaves rosulate, entire or sparingly toothed, hirsute with 

 branched hairs; stem-leaves lanceolate; racemes elongate; petals yellow, 2-3 mm. 

 long; fruiting pedicels 5-8 mm. long; pod erect, oblong, 6-10 mm. long, 2 mm. 

 wide. Mountains: (? N.M.) Colo. Utah. Submont. 'Mont. Je-S. 



7. D. praealta Greene. Winter annual; stems usually several from the 

 base, leafy; basal leaves lanceolate or oblanceolate, stellate, 1-3 cm. long, entire 

 or slightly dentate; stem-leaves ovate, small; petals white, spatulate, 2-3 mm. 

 long; fruiting pedicels 5-7 mm. long; pods oblong, about 1 cm. long, 2-3 mm. 

 wide. D. yellow stonensis A. Nels. D. lapilutea A. Nels. Mountain slopes: 

 Wyo. Alta. B.C. Submont. Je-Jl. 



8. D. deflexa Greene. Winter annual; stem stout, 7-10 cm. high, racemose 

 almost from the base; leaves mostly basal, oblong-lanceolate, entire or sparingly 

 toothed, hirsute-ciliate on the margins; petals white; pedicels spreading, much 

 exceeding the pod; pod elliptic, 6-8 mm. long. Dry places: Wyo. 



9. D. br achy carp a Nutt. Annual; stem usually much branched, stellate; 

 leaves ovate to lanceolate, entire, 1 cm. long or less, thick, finely stellate; petals 

 yellow or whitish, 2 mm. long; pedicels 3-4 mm. long; pod oblong, 2-5 mm. 

 long. Dry hills and fields: Va. Ga. La. Colo.; Ore. Mont. Plain. 

 Mr-My. 



10. D. lutea Gilib. Winter annual of the habit of D. nemoralis; stems 1-4 

 din. high, branched; basal leaves obovate or oblanceolate, densely and coarsely 

 stellate; stem-leaves ovate, usually coarsely toothed; petals yellow, or in age 

 paler, 2-3 mm. long; fruiting pedicels 15-30 mm. long, ascending or spreading; 

 pod oblong, 5-10 mm. lone;, 2 mm wide. D. nemorosa leiocarpa Lindb. (?) D. 



