130 COMMON CANADIAN WILD PLANTS. 



41. BIDENS, L. BtrR-MAKiGOLD. 



1. B. fFOndo'sa, L. (Common Beggak-ticks.) Bays none. 

 Achenes flat, wedge-obovate, ciliate on the margins with 

 bristles, pointing upwards, 2-awned. Stem tall, branched. 

 Leaves thin, long-petioled, pinnately 3-5-divided, the leaf- 

 lets ovate-lanceolate, pointed, serrate. 



2. B. GOnna'ta, Muhl. (Swamp Beggar-ticks.) Bays 

 none. Achenes flat, narrowly wedge-shaped, 2-4-awned, 

 ciliate with minute bristles, pointing downwards. Stem 1-2 

 feet high, smooth. Leaves lanceolate, pointed, serrate, 

 tapering and connate at the base, the lowest often 3-parted 

 and deourrent on the petiole. — In shallow water and low 

 grounds. 



3. B. eer'nua, L. (SmallebBtjb-Marigold.) Bays short, 

 pale yellow. Achenes flat, wedge-obovate, 4-awned, ciliate 

 with bristles pointing downwards. Stem nearly smooth, 

 5-10 inches high. Leaves all simple, lanceolate, nnequaUy 

 serrate, hardly connate. Hoads nodding. — "Wet places. 



4. B, ehrysanthemoi'des, Michx. (Large Bub-Mabi- 

 GOLD.) Bays an inch long, showy, golden yellow. Achenes 

 wedge-shaped, 2-4-awned, bristly downwards. Stem smooth, 

 6-30 inches high, erect or ascending. Leaves lanceolate, 

 tapering at both ends, connate, regularly serrate. — Swamps 

 and ditches. 



5. B. Beek'ii, Torr. CWatebMaeigoLd.) Aquatic. Stems 

 long and slender. Immersed leaves dissected into fine hair- 

 like divisions ; those out of water lanceolate, slightly con- 

 nate, toothed. Eays showy, golden yellow, larger than the 

 involucre. Achenes linear, bearing 4-6 very long awns barbed 

 'towards the apex. — Ponds and slow streams. 



42. HEUOP'SIS, Pers. Ox-Eye. 



1. H. Isevis, Pers. Stem smooth, slender, branching. 

 Leaves ovate-lanceolate, acute, sharply serrate, on slender 

 petioles. Heads showy ; peduncles elongated. — Dry open 

 thickets : London and westward. 



