MUSTARD FA:mILY 343 



1. C. cheiranthoides (L.) Link. Annual; stem 3-6 dm. high, fineh' 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: Xe'R-f. — N.C. — Utah — Alaska; Eu. 

 Plain — Mont. J^Au. 



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

 leaves hnear or oblanceolate, mosth' 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. parri- 

 florum Xutt. Dn,- soil: Minn. — Colo. — Xev. — 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 ver>' 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. Xels.) Rydb. Biennial; stem branched at the base, 3^ dm. 

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

 16-20 mm. long, pale 3'ellow; pedicels ascending; pod ascending, suliterete, 8-12 

 cm. long; stvle 2 mm. long. Cheiranthus aridus A. Xels. Desert regions: Wj'o. 

 —Utah. Je. 



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

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

 petals light j'ellow, 15-18 mm. long; pedicels divergent; pods divergent, 2 mm. 

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

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



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

 Unear, deeply sinuate-dentate, sometimes almost hTate-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 Xutt. Hills and plains: Sask. — S.D. — X.M. — Calif. — Wash. Submont. 

 —Mont. My-Jl. 



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

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

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

 mm. long. Cheiranthus asperrimus Greene. Drj- hills: S.D. — X.M. — Ariz. — 

 Mont. Submont. Mj'-Au. 



8. C. oblanceolata Rj-db. 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; stjde about 1 mm. long. E. oVanceolatum 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) R\'db. Biennial or perhaps perennial: stem 3-5 dm. 

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

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

 not A. Xels. C. Bakeri Greene. Hills: X.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. Clavej- bluffs and bad lands: S.D. — 

 Colo. Plain. My-Je. 



