April, 1905.] Notes — Ohio State Herbarium. III. 319 



8. Bidens vulgata Greene. Stem stout, erect and branching, 

 5-16 dm. high. Leaves pinnately 3-5-divided, on long petioles, 

 leaflets lanceolate, acuminate, coarsely and sharply serrate or 

 almost incised, 5-12 cm. long. Heads comparatively few, 

 mostly on long stout peduncles, the largest becoming 2 cm. high 

 and 3 cm. across in fruit, outer bracts 10-16, spatulate oblong, 

 unequal and conspicuously exceeding the disk, ciliate at base; 

 achenes brown, obovate, flat, 7-10 mm. long, the two awns 4-6 

 mm. long. 



Abundant in moist soil throughout the state. It has long 

 been confused with Bidens frondosa, and under that name has 

 been included in Gray's Manual and the Illustrated Flora. It is 

 distinguished from Bidens frondosa by the larger heads, the 

 coarser leaves, the more ascending branches, and the large broad 

 achenes. The bracts, which are ciliate in Bidens vulgata, may 

 possibly serve also as a distinguishing character. 



9. Bidens trichosperma (Michx.) Britton. Tall and freely 

 branched above in the usual form, although in peat bogs it mav 

 bloom when but 2-3 dm. high. Leaves petioled, 1-2-pinnately 

 parted, segments 3-10, narrowly linear-lanceolate or linear, 

 acuminate at base and apex, sharply serrate along the middle or 

 almost entire. Heads numerous and showy, outer bracts linear- 

 spatulate, about equalling the disk; achenes cuneate, 5-6 mm. 

 long, awns 2-3 mm. long, narrowly triangular, upwardly hispid 

 or becoming smooth. 



Throughout the state, except possibly the extreme southern 

 part, but especially common at the north. Widely variable in 

 size and especially in the shape of the leaf -segments, which in 

 specimens from peat-bogs are sometimes linear-spatulate, entire 

 and rounded at the apex. From this extreme there is every 

 gradation to the typical linear-lanceolate shape. The variety 

 tenuiloba has been reported from the state and is undoubtedly 

 included in the preceding description, but there is no valid reason 

 for separating two forms in the Ohio material at hand. 



10. Bidens aristosa (Michx.) Britton. Stems erect, freely 

 branching, 4-10 dm. high. Leaves petioled, pinnately divided, 

 segments 3-7, lanceolate, sharply serrate, acuminate at both 

 ends. Heads very numerous, with conspicuous rays, outer 

 bracts oblong or oblong-spatulate, equalling or shorter than the 

 disk; achenes broadly obovate, 4 mm. long, with two slender 

 barbed awns 3-4 mm. long. 



This western species has so far been reported only from the 

 western part of the state. Three specimens are in the State Her- 

 barium, from Champaign, Clark, and Madison Counties. Although 

 in general habit it resembles Bidens trichosperma, it is easily and 

 certainly distinguished from it by the broad achenes with their 

 long slender awns. 



