MUSTARD FAMILY 343 



1. C. cheiranthoides (L.) Link. Annual; stem 3-6 dm. high, finely strigose; 

 leaves lanceolate or linear-lanceolate, 2-10 cm. long, entire or sinuate-denticu- 

 late; petals 4-5 mm. long; fruiting pedicels spreading or ascending; pod 2-3 cm. 

 long, 1-1.5 mm. thick, erect. Erysimum cheiranthoides L. WORMSEED MUS- 

 TARD. Waste places and river bottoms: Newf. N.C. Utah -Alaska; Eu. 

 P lain Mon t , Je- Au . 



2. C. inconspicua (S. Wats.) Rydb. Biennial; stem 3-6 dm. high, angled; 

 leaves linear or oblanceolate, mostly entire, canescent; petals pale yellow, 8-10 

 mm. long, claw shorter than the sepals; pedicels strongly ascending; pods erect, 

 1.5-5 cm. long, about 2 mm. thick. E. asperum inconspicuum S. Wats. E. parvi- 

 florum Nutt. Dry soil: Minn. Colo. Nev. B.C. Plain Submont. Je-Au. 



3., C. repanda (L.) Link. Annual; stem 3-4 dm. high, much branched; 

 leaves lanceolate or oblanceolate, 3-8 cm. long, repand-dentate or the lower 

 coarsely toothed; petals 6-9 mm. long, light yellow; pods 4-8 cm. long, about 

 2 mm. thick; style very short and stout. E. repandum L. Waste places: Ohio 

 Kans. -Ariz. Utah; also as a ballast plant at sea-ports; adv. or nat. from 

 Eu. Plain Son. My-Jl. 



4. C. arida (A. Nels.) Rydb. Biennial; stem branched at the base, 3-4 dm. 

 high; leaves oblanceolate, entire or nearly so, 4-8 cm. long, grayish green; petals 

 16-20 mm. long, pale yellow; pedicels ascending; pod ascending, subterete, 8-12 

 cm. long; style 2 mm. long. Cheiranthus aridus A. Nels. Desert regions: Wyo. 

 Utah. Je. 



6. C. aspera (Xutt.) Rydb. Biennial; stem 2-4 dm. high, mostly simple; 

 leaves lanceolate or linear-lanceolate, usually somewhat sinuately dentate; 

 petals light yellow, 15-18 mm. long; pedicels divergent; pods divergent, 2 mm. 

 thick; beak about 1 mm. long, thick. Cheiranthus asper Nutt. E. asperum 

 DC. Plains: Man. Kans. e N.M. -e Mont. Plain Submont. Je-Au. 



6. C. elata (Nutt.) Rydb. Biennial; stem 3-10 dm. high, strigose; leaves 

 linear, deeply sinuate-dentate, sometimes almost lyrate-pinnatifid, or the basal 

 ones oblanceolate; petals usually bright yellow, 15-18 mm. long; pedicels ascend- 

 ing; pods usually erect, 4-6 cm. long, 2 mm. thick; beak nearly 2 mm. long. E. 

 elatum Nutt. Hills and plains: Sask. S.D. -N.M. 'Calif. 'Wash. Submont. 

 Mont. My-Jl. 



7. C. asperrima (Greene) Rydb. Biennial; stems 2-5 dm. high, usually 

 simple; leaves linear, 5-8 cm. long; petals 10-15 mm. long, usually pale yellow; 

 pedicels ascending; pods strictly erect, 5-8 cm. long, 1-1.5 mm. thick; beak 1 

 mm. long. Cheiranthus asperrimus Greene. Dry hills: S.D. N.M. Ariz. 

 Mont. Submont. My-Au. 



8. C. oblanceolata Rydb. Biennial; stem 4-6 dm. high; leaves narrowly 

 oblanceolate, 5-12 cm. long; petals yellow, about 15 mm. long; blades almost orbi- 

 cular; fruiting pedicels ascending or spreading; pod ascending, about 8 cm. long, 

 about 1.5 mm. thick; style about 1 mm. long. E. oblanceolatum Rydb. Moun- 

 tains: Colo. Wyo. Utah. Submont. Subalp. My-Au. 



9. C. brachycarpa Rydb. Biennial; stem 3-6 dm. high, grayish canescent; 

 leaves linear-spatulate or oblanceolate, 5-10 cm. long, the lower petioled and 

 minutely denticulate; petals nearly 2 cm. long, bright yellow; fruiting pedicels 

 about 8 mm. long, strongly ascending; pod erect. Hills: Utah. Submont. 

 Je-Au. 



10. C. Bakeri (Greene) Rydb. Biennial or perhaps perennial; stem 3-5 dm. 

 high; leaves narrowly linear; petals bright yellow, 15-18 mm. long; pedicels 

 strongly ascending, nearly 1 cm. long; pod erect. Cheiranthus aridus Greene, 

 not A. Nels. C. Bakeri Greene. Hills: N.M. Colo. Submont. Ap-Je. 



11. C. argillosa (Greene) Rydb. Biennial; stem usually simple, 1-3 dm. 

 high; leaves linear-lanceolate or linear, crowded below; petals pale yellow, about 

 15 mm. long; pedicels ascending, 5-8 mm. long; pods erect, 5-7 cm. long, 2 mm. 

 thick. Cheiranthus argillosus Greene. Clayey bluffs and bad lands: S.D.- 

 Colo. Plain. My-Je. 



