Fig. 772: a, Bidens leptocephala: a, habit, upper part of plant, x V^. b-k, Bidens 

 Bigelovii: b, habit, upper part of plant, x 14; c, head, x 2V2', d, inner and outer in- 

 volucre bracts, x 5; e, disk flower, x 5; f, corolla spread out, x 5; g, stamens spread 

 out, X 5; h, style branches, x 5; i and j, outer achenes (j, sterile), x 5; k, inner achene, 

 X 5. (V. F.). 



