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82 THE AMERICAN MIDLAND NATURALIST. 
Radicula armoracia (1,.) Robinson. HORSERADISH. 
Fields and roadsides. Occasionally escaped from cultivation and 
persisting. May 30 (June 1). 
Sisymbrium officinale (1,.) Scop. HEDGE MUSTARD. 
Streets. Occasional. 
Sisymbrium altissimum 1. TUMBLING MUSTARD. 
Roadsides and fields. Common. June to (11). 
Sophia sophia (1,.) Britton.’ FLIX WEED. 
Along railroad. Occasional. June Io. 
Sophia incisa (Engelm.) Greene. TANSY MUSTARD, 
Fields and roadsides. Common. May 30 (29). 
Sophia hartwegiana Fourn. HARTWEG’S TANSY MUSTARD 
Dry roadside. Frequent. June 25. 
Erysimum chieranthoides \. WORM-SEED MUSTARD. 
Common in woods and thickets; less so in open places. Ap- 
parently only one flowering record (June 20) besides an extremely 
early one of Apr. 10, Ig10. 
Erysimum inconspicuum (S. Wats.) Mac. M. 
Prairie. Common. June 20 (18). , 
Barbarea barbarea (1,.) MacM. WINTER CRESS. 
Collected by C. H. Waldron in rg1o. 
Brassica nigra (1,.) Koch. BLACK MUSTARD. 
Roadsides. Rare. 
Brassica juncea (1,.) Cosson. INDIAN MUSTARD. 
Roadsides and fields. Frequent. June 15 (scant data). 
Brassica arvensts (1,.) B. S. P. COMMON MUSTARD. 
Fields and roadsides. Common. May 30 (31). 
Brassica campestris \. 
Roadsides. Occasional. 
Erucastrum pollichit Schimp. & Spenn. DOG MUSTARD. 
Frequent along the railroad tracks and occasional along streets. 
June 15. This common name which is proposed is a contraction 
of one used in a European manual. The plant sflower vigorously’ 
in the fall until after the first frost, frequently into November. 
Eruca eruca (1,.) Britton. GARDEN ROCKET. 
Collected by L. R. Waldron in 1902, by Bergman in 1912. 
Draba nemorosa \,. YELLOW WHITLOW GRASS. 
Fields. Occasional. Only one early record—Apr. -24, 1910. 
Arabis hirsuta (1,.) Scop. HAIRY ROCK CRESS. 
Common in prairie, occasional in fields. June 20. 
