160 BRASSIACEAE. 



6. Erysimum oblanceolatum Rydb. In the mountains of Wyo. and Colo. 

 Alt. 5000-11,000 ft. Golden; near La Plata Post Office; Hamor's Lake, above 

 Durango; Williams' Canon; near Pueblo; Georgetown; Stove Prairie Hill; 

 Cameron Pass ; Dixon Canon ; plains and foot-hills near Boulder ; Alpine 

 Tunnel ; Cimarron. 



7. Erysimum Bakeri (Greene) Rydb. (Chicranthus aridus Greene; C. 

 Bakeri Greene) On dry hills in Colo, and N. M. Golden City. 



8. Erysimum argillosum (Greene) Rydb. (C. argillosus Greene) On dry 

 mesas and bluffs of Colo. Alt. about 5000 ft. Pueblo; plains near Denver; 

 bluffs north of La Porte. 



9. Erysimum nivale (Greene) Rydb. (C. nivalis Greene) In the higher 

 mountains of Wyo. and Colo. Alt. 11,000-13,000 ft. Mountains northeast 

 of Boreas ; mountains above Graymont ; mountain northwest of Como ; above 

 Ouray ; Carson ; Argentine Pass ; Mt. Hesperus, above timber line ; Slide 

 Rock Canon ; West La Plata Mountains. 



10. Erysimum radicum Rydb. On the higher peaks of Colo. Alt 10,000- 

 13,000 ft. Pike's Peak; Bottomless Pit. 



11. Erysimum Wheeleri S. Wats. (E. aspcrum alpestrc Cockerell) On 

 dry hills and plains in the mountains from Colo, and Utah to Tex. and Ariz. 

 Alt. 5000-12,000 ft. Mountains between Sunshine and Ward ; plains and 

 foot-hills near Boulder; East Indian Creek; Turkey Creek and tributaries; 

 Veta Mountain; Ojo; west slope Bald Mountain; Slide Rock Canon, West 

 La Plata Mountains ; foot-hills near Ft. Collins ; mountains near Veta Pass ; 

 headwaters of Pass Creek ; Horsetooth Gulch ; Howe's Gulch ; Montrose ; 

 Dillon Canon ; Chicago Lakes; near Boulder. 



12. Erysimum amoenum (Greene) Rydb. (Cheiranthus nivalis amocnus 

 Greene.) On the higher peaks of Colo. Alt. 10,000-13,000 ft. La Plata 

 Mountains ; Silverton ; near Ironton, San Juan Co. ; Mt. Abram ; mountains 

 near Ouray; Berthoud Pass. 



17. BARB ARE A L. WINTER-CRESS, SCURVY-GRASS. 



Pods sharply 4-angled, stout-pediceled ; leaf-segments 4-8 pairs, i. B. praecox. 

 Pods obtusely 4-angled ; leaf-segments 1-4 pairs. 2. B. americana. 



1. Barbarea praecox (J. E. Smith) R. Br. In waste places from N. Y. 

 to Wash., Fla. and Calif. ; sparingly introduced from Europe. Hotchkiss. 



2. Barbarea americana Rydb. (B. vulgaris gracilis S. Wats.; not DC.) 

 In rich soil from Sask. and Mont, to Colo, and Nev.- Between Eldora and 

 Baltimore. 



18. SINAPIS L. WHITE MUSTARD. 



i. Sinapis alba L. Introduced in grain fields and waste places from Me. 

 to B. C. and Calif. Ft. Collins. 



19. BRASSICA L. WILD MUSTARD, TURNIPS, CABBAGE. 



Pedicels 1-2 cm. long: plant glabrous. i. B. juncea. 



Pedicels about 5 mm. long ; plant sparingly hispid. 2. B. arvensis* 



i. Brassica juncea (L.) Coss. Sparingly introduced from Europe; in 

 waste places from N. H. to Colo., Va. and N. M. Alt. about 8000 ft. Hills 

 about Box Canon, west of Ouray. 



