3i8 The Ohio Naturalist [Vol. V, No. 6, 



their characteristic elHptical shape and tapering base easily dis- 

 tinguish it from that species and warrant its elevation to specific 

 rank. 



4. Bidens connata Muhl. Stem erect, branching above, 4-10 

 dm. high. Leaves lanceolate, sharply serrate, long acuminate at 

 base and apex. Heads numerous, about 6 mm. high, rays none; 

 outer bracts of the involucre about 5, 1-1.5 times as long as the 

 disk, lanceolate-oblong, entire or minutely toothed; corollas 

 5-lobed; achenes cuneate, 5 mm. long, awns 2 mm. long, 

 retrorsely barbed. 



There is but one specimen in the State Herbarium, from 

 Wyandot County. 



5. Bidens comosa (Gray) Wiegand. Stem diffusely branch- 

 ing from the base, or with short branches above, 2-7 dm. high. 

 Leaves elliptic, lanceolate, or narrowly ovate-lanceolate, coarsely 

 toothed, acute or acuminate, tapering at the base into a winged 

 petiole. Heads usually numerous, about 1 cm. high in flower, in 

 fruit becoming 2 cm. high and 3 cm. in diameter, outer bracts 

 6-8, oblong to oblanceolate, foliaceous, serrate, twice as long as 

 the disk or longer and reaching a length of 8 cm. ; corollas 

 4-lobed; achenes 7-10 mm. long, awns three, the longest 4-6 mm. 



Abundant in wet places, probably throughout. 



6. Bidens discoidea (T. & G.) Britton. Stem freely branched, 

 5-15 dm. high. Leaves 3-divided, on slender petioles, leaflets 

 lanceolate or narrowly ovate-lanceolate, sharply serrate, acute 

 at the base, long acuminate at the apex. Heads numerous, 5 

 mm. high in flower, outer bracts 4, narrowly spatulate, exceed- 

 ing the disk; achenes cuneate, about 5 mm. long, the two awns 

 about 2 mm. in length. 



One specimen from Cedar Point, Erie County. 



7. Bidens jrondosa L. Sparingly branched with spreading 

 branches, 6-10 dm. high. Leaves 3-divided, usually thin, on 

 slender petioles 3-5 cm. long, leaflets ovate-lanceolate, acute or 

 rounded at the base, acute or short-acuminate at the apex, 5-8 

 cm. long. Heads relatively few, 5 mm. high in flower, much 

 larger in fruit, outer bracts 6-8, narrowly spatulate, conspic- 

 uously exceeding the disk, naked or sparingly ciliate at the base; 

 achenes oblong or cuneate, dark brown to black, 6-8 mm. long, 

 awns two, 4 inm. long. 



The three specimens in the State Herbarium, from Holmes, 

 Meigs and Vinton counties, have been confused with Bidens 

 discoidea. The^two species^are at once separated by the more 

 numerous outer bracts and the much larger achenes of Bidens 

 jrondosa, as well as by the laxer habit of branching in the latter 

 species. According to Wiegand the leaves are sometimes 

 5-tlivided, but this was not ol)scrvcd in any Ohio s])ccimens. 



