.|-S 



I I iMI'OSITAE. 



Vol. III. 



g. Bidens bipinnata L. Spanish Needles. 

 Cuckolds. Fig. 4513. 

 Bidens bipinnata L. Sp. PI. 832. 1753. 



Annual; stem quadrangular, erect, freely branch- 

 id. rather slender, i-5 high. Leaves thin, acumi- 

 nate, petioled, 1-3-pinnately dissected into ovate or 

 oblong, toothed or lobed segments, the lower often 

 8' long; heads usually numerous, long-peduncled, 

 2"~4" broad ; involucre narrow, its outer bracts 

 linear, ascending, nearly as long as the broader erect 

 inner ones ; rays 3-4, yellow, short, sometimes none ; 

 achenes linear, 4-angled, slightly pubescent, narrowed 

 upward into a beak. 5"-o" long, the outer ones com- 

 monly shorter and thicker than the inner ; pappus 

 of 2-4 (usually 4), downwardly barbed, slightly un- 

 equal, spreading awns, much shorter than the achene. 



In various situations, often a weed in cultivated fields, 

 Rhode Island to Florida, Ohio, Nebraska, Kansas and 

 Arizona. Introduced as a weed into southern Europe 

 and Asia. July-Oct. 



10. Bidens coronata (L.) 

 Tickseed-Sunflower. 



Fig. 



Fisch. Southern 

 45 H- 



Coreopsis coronata L. Sp. PI. Ed. 2, 1281. 1763. 



Coreopsis aurea Ait. Hort. Kew. 3: 252. i? 8 9. 



Bidens coronata Fisch.; Steudel, Norn. Ed. 2, 202. 1840. 



Annual, glabrous or nearly so throughout; stem 

 branched, i-3 high. Lower leaves petioled, 3-5 

 long, 3-divided, the terminal segment lanceolate, acute 

 or acuminate, serrate, much larger than the serrate 

 or entire lateral ones; upper leaves much smaller, 

 3-parted, 3-lobed or undivided, sessile or short- 

 petioled, entire or serrate; leaves rarely all undi- 

 vided; heads numerous, slender-peduncled, 1-2' 

 broad; involucre hemispheric, its outer bracts linear- 

 oblong, obtuse, equalling or slightly exceeding the 

 broader inner ones; rays 6-10, obtuse; achenes 

 broadly cuneate, slightly pubescent, I "-2" long; pap- 

 pus of 2 chaffy blunt divergent somewhat laciniate 

 teeth, rarely with 2 shorter intermediate ones. 



In wet places, Virginia to Florida and Alabama. July 

 Sept. 



11. Bidens trichosperma (Michx.) Britton. 

 Tall Tickseed-Sunflower. Fig. 4545. 



C. trichosperma Michx. Fl. Bor. Am. 2: 139. 1803. 



B. trichosperma Britton, Bull. Torr. Club 20: 281. 1893. 



Coreopsis trichosperma var. tenuiloba A. Gray, Syn. Fl. 



1 : Part 2, 295. 1884. 

 Bidens trichosperma tenuiloba Britton, Bull. Torr. Club 



20 : 281. 1893. 



Annual or biennial, glabrous; stem tall, obscurely 

 quadrangular, much branched, 2-5 high. _ Lower 

 leaves petioled, 4'-8' long, pinnately divided into 5-7 

 lanceolate or linear, acuminate, sharply serrate, in- 

 cised or nearly entire, sessile or short-stalked seg- 

 ments; upper leaves sessile or nearly so, 3-lobed, 

 3-divided, or entire and linear-lanceolate; heads nu- 

 merous, 1Y-2Y broad, long-peduncled; involucre 

 hemispheric, its outer bracts linear or spatulate, 

 sometimes ciliate, about the length of the broader 

 inner ones ; rays 6-19, obtuse, golden yellow, J"-i2" 

 long; achenes oblong-cuneate or the inner ones nar- 

 rower, hispid-pubescent and ciliate, 2"-4" long; pap- 

 pus of 2 short erect or divergent, upwardly hispid 

 teeth or short awns. 



In swamps and wet meadows, Massachusetts to Georgia 

 Recorded from Ontario and Minnesota. Aug. -Oct. 



Illinois to Michigan and Kentucky. 



