338 CRUCIFERAE 



1. L. campestre (L.) R. Brown. In fields and waste places: N. S. 



and Ont. to Va., Kan. and on the Pacific Coast. Naturalized 

 from Europe. 



A troublesome weed in many parts of our range. 



2. L. Draba L. On ballast: near Astoria, L. I., and Syracuse, 



N. Y., also near the seaports. Fugitive from Europe. 

 A rare adventive near New York and at Swartzwood Lake, N. J. 



3. L. virginicum L. In fields and along roadsides: Quebec to 



Minn., Colo., Fla., Tex. and Mex. Also in the W. I. 

 Common throughout the area. 



4. L. ruderale L. In waste places, on ballast and along roadsides : 



N. S. to Tex. 



Rare as an occasional adventive near New York and Philadelphia . 

 Reported from near Bridgeport, Conn. 



5. L. densiflorum Schrad. On ballast: near the eastern sea- 



ports. . 



Common throughout the area as a weed. Previously confused 

 with the Asiatic L. apetalum Willd. 



L. ncgleclum Thell, also found in waste places, with characters apparently inter- 

 mediate between those of L. virginicum and L. densiflorum, may be a hybrid between 

 these species. 



The garden cress, L. sativum L., is frequently a short-lived escape from cultiva- 

 tion. Other species which are sometimes found as waifs are L. gratninifolium L. and 

 L. Smithii Hook. 



2. Carara Medic {Coronopus Gaertn.) 



Pod rugose, not crested. 1. C. didymd. 



Pod coarsely wrinkled, crested. 2. C. Coronopus. 



i. C. didyma (L.) Britton. In waste places: Newf. to Fla., Mo. 

 and Tex., west to Cal. Naturalized from the South. 



A rather common weed near Philadelphia, Jersey City and about 

 the Metropolitan Area. 



2. C. Coronopus (L.) Medic. In waste places and on ballast: 

 N. B. to Fla. and Tex., and on the Pacific Coast. Fugitive 

 or adventive from Europe. 



Not uncommon near the edges of N. Y. City. 



3. Thlaspi [Tourn.] L. 

 1. T. arvense L. In waste places and on ballast: Que. to Man., 

 the N. W. Terr., N. Y. and Kan. 

 Not uncommon near the larger cides in the area. 



