188 Class XIX. Order I. 



226. BIDENS. 

 BIDEKS FRONDOSA. L. Burn marygold, 



Flowers discoid ; outer calyx six times as long 

 as the flower, its leaves ciliate at base ; lower 

 leaves pinnate, upper ones ternate, lanceolate, ser- 

 rate. Willd. 



A frequent and troublesome weed in corn fields, especially 

 where the soil is moist. Stem smooth, three or four feet high. 

 Lower leaves five-pinnate, sometimes ternate, leafets lanceo- 

 late, serrate. Flowers terminal, erect, flosculous, surrounded 

 by a large, leafy involucrum or outer calyx. Florets small, 

 yellow. Seeds oblong, flat, tipt with two barbed awns, by 

 which they adhere to the clothes, and to the coats of animals. 

 August, September. Annual. 



BIDENS CRYSANTHEMOIDES. Mich. Large flowered Bidens. 



Flowers erect, radiate ; outer calyx waved, 

 much shorter than the rav ; leaves lanceolate, ser- 



V ' 



rate, connate. 



The large, golden flowers of this plant are very conspicu* 

 ous in wet situations in autumn. Its tops are usually eaten off 

 when accessible to cattle, who appear fond of it. Stem erect, 

 round, smooth. Leaves glabrous, lanceolate, slightly toothed, 

 tapering at both ends, slightly connate at base. Flowers erect. 

 Leaves of the outer calyx oblong, obtuse, waved up and down 

 on the margin ; those of the inner calyx shorter, oval, acute. 

 Ray very large, spreading, yellow. Seeds with commonly four 

 awns, in which circumstance our plant seems to differ from that 

 of Michaux. September, October. Annual. 



227, MIKANIA. 

 MIKANIA SCANDENS. Willd. Climbing Mil-aiiiy. 



Stem climbing, glabrous ; leaves heart-shaped,. 



