LIST OF HIGHER SEED-PRODUCING PLANTS. 585 



Ambrosia triflda Linn. Spec. 987 (1753). 

 Wats, and Coult., Gray's Man. 6 ed. 273; Britt , Fl. N. J. 145; Webb., 

 Fl. Neb. 147, Mac, Fl. Can. I. 240; Chap., Fl. S. St. 223; Coult., Fl. Colo. 

 180; Upham, Fl. Minn. 79; Mac, Fl.Can. I, 549; Roth., Wheel. Exp. 158; 

 Gov., Fl. Ark. 194; Gray, Syn. Fl. I, 2, 249: Coult., Fl. Tex. 209. 



North America: Q., Ont. to Man. and Colo. ; S. to Mo., 

 Tex., Ark. and Fla. 



Minn, valley: Throughout; gullies, ravines and thick- 

 ets or along roads. 



Herb. : Ballard S4.5, Page lake, Carver Co. ; Taylor 

 1029, Glenwood; Sandberg 31^, Goodhue Co.; Herb. Moyer 133, 

 Montevideo. 



Ambrosia trifida Linn. var. inlegrifolia (Muhl.) T. and G 

 Fl. II, 354 (1841). 



A. integrifolia Muhl. Willd. Spec. IV, 375 (1805). 

 Wats, and Coult., Gray's Man. 6 ed. 273; Britt., Fl. N. J. 143; Upham, 

 Fl. Minn. 79; Mac, Fl. Can. I, 240; Chap., Fl. S. St. 223; Gray, Syn. Fl. 

 I, 2, 249. 



North America: With species; westward; Ills, to N. 

 Y. and Va. 



Minn, valley: Throughout at higher levels; local or 

 infrequent; habitat with the species. 



Herb.: Sheldon 1332, Lake Benton. 



XANTHIUM Linn. Gen. 717 (1737). 

 Baillon, Hist. PI. VIII, 287; Benth. and Hook., Gen. PL II, 355; Eng- 

 ler and Prantl. Nat. Pjianz. IV, 5, 222; Durand, Ind. Gen. Plian. 207. 



Living species: 3-4; temperate and warmer regions, 

 around the world. Russia, 3; Europe, 3; Russian Europe, 2; 

 N. America, 3-4; Canada, 1-2; California, 1; Rocky mts., 1; 

 E. Sts., 1-2; W. Tex., 2-3. 



Xanthium caiiadense Mill. Diet. ed. 8 (1768). 



X. orientale Linn. Spec. (1753) in part. 

 X. carolinense Dill. Elth. II, 432 (1774). 

 X americanum Walt. Fl. Car. 231 (1788). 

 X. macrocarpum var. glabratum DC. Prodr. V, 523 (1836 \ 

 X strumarium var. canadense T. and G. Fl. II, 294 (1841). 

 X. strumarium AUCT. Amer. 

 Wats, and Coult., Gray's Man. 6 ed. 274; Coult., Fl. Colo., 182; Webb., 

 Fl. Neb. 147; Mac, Fl. Can. I, 241; Upham, Fl. Minn. 79; Chap., Fl. S. 

 St. 224; Roth., Wheel. Exp. 159: Wats., King Exp. 166; Engl. Hoffmann, 

 Nat. Pflanz. IV, 5, 223: Gray, Syn. Fl. I, 2, 252; Coult Fl. Tex. 211. 



North America: N. W. T. to Tex.; W. to Calif, and 

 Nev. ; E. to Saskatchewan, Minn., Neb., Ark.? Ga. 



Minn, valley: Throughout, especially N. E. ; sterile 

 places, banks and fields. 



