LIST OF HIGHER SEED-PRODUCING PLANTS. 535 



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; 

 Cov., 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.: Bollard 84.0, Page lake, Carver Co.; Taylor 

 1029, Gleiiwood',.Sandberg 3 14, Goodhue Co.; Herb. Moyer 133, 

 Montevideo. 



Ambrosia triflda LINN. var. integrifolia (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. PL VIII, 287; Benth. and Hook., Gen. PL II, 355; Eng- 

 ler and Prantl, Nat. Pflanz. IV, 5, 222; Durand, Ind. Gen. Phan. 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 canadense 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. gldbratum DC. Prodr. V, 523 (1836). 

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

 X. strumarium AUCT. AMEB. 



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; Both., 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. 



