220 COMPOSITE. (composite family.) 



$ 1 . Corolla of the ray and disk yellow : branches of the style tipped with a pointed 



or acute appendage. 



* Achenia wingless, wedge-oblong, flat, 2-awned or 2-toot/ied : scales of the outer invo 

 lucre leafy, reflexed: leaves opposite, petioled, generally pinnately or ternately com- 

 pound, the leaflets serrate: biennials? (Plants with the aspect of Bidens, but 

 the awns barbed upwardly.) 



•i-Rays wanting. 



1. C discoidea, Ton - . & Gr. Smooth, diffusely branched; leaves ter- 

 nately divided; leaflets ovate-lanceolate, pointed, coarsely sen-ate; heads panicu- 

 latc-corymbcd ; outer involucre of 3 - 5 foliaccous bracts usually much longer than 

 the heads ; achenia hairy ; the awns or teeth as long as the corolla, barbed upward. 

 Swamps, 111., Ohio and southward. July -Sept. — Plant l°-2° high. 



2. C, bidentoides, Nutt. Dwarf diffusely branched, smoothish ; leaves 

 lanceolate-linear, cut-toothed, tapering into a petiole ; amis slender, upwardly 

 barbed, much longer than the corolla or the bristly young achenium. — Near Phil- 

 adelphia, Nuttall. — A very obscure species. 



-t- ■*- Rays conspicuous (golden-yellow and showy). 



3. C. tricliosperma, Michx. (Tickseed Sunflowsr.) Smooth, 

 branched ; leaves short-petioled, 5 - 7-divided ; leaflets lanceolate or linear, cut- 

 toothed, or the upper leaves only 3 - 5-cleft and almost sessile ; heads panicled- 

 corymbose ; achenia narrowly wedge-oblong, bristly-ciliatc above, crowned with 2 

 triangular or awl-shaped stout teeth. — Swamps, Massachusetts to Virginia near 

 tho coast. Sept. 



4. C. aristdsa, Michx. Somewhat pubescent ; leaves 1 - 2-pinnately 

 5 -7-divided, petioled; leaflets lanceolate, cut-toothed or pinnatifid ; heads pani- 

 cled-corymbose ; outer involucre of 10-12 leafy bracts; achenia oblong-obovate, 

 obscurely margined, bristly-ciliate, with 2-4 long and slender diverging awns (in 

 one variety awnless). — Swamps, Michigan to "Wisconsin, and southward. Aug. 



* * Achenia elliptical, narrowly winged, the narrowly notched summit of the wing 

 minutely lacerate-toothed : scales of the outer involucre foliaceous, much smaller than 

 the inner, all united at the base: rays obtuse, entire: leaves opposite, petioled, 3- 

 5-divided : perennial. 



5. C. tl'ipteris, L. (Tall Coreopsis.) Smooth; stem simple (4°- 

 9° high), corymbed at the top ; leaflets lanceolate, acute, entire. (Chrysostem- 

 ma. Less.) — Penn, and Michigan to Illinois and southward. Aug. — Heads 

 exhaling the odor of anise when bruised : disk turning brownish. 



* * * Achenia oblong, narrowly winged, minutely or obscurely 2-toothed at the sum- 

 mit : scales of the outer involucre narrow, about the length of the inner, all united at 

 the base : rays mostly entire and acute : leaves opposite, sessile, mostly Z-divided, 

 thei-efore appearing as if whorled: perennial (l°-3° high). 



6. C senifolia, Michx. Leaves each divided into 3 sessile ovate-lanceo- 

 late entire leaflets, therafore appearing like 6 in a whorl : plant minutely soft 

 pubescent. — Sandy woods, Virginia and southward. July. 



Var. stellata, Torr. & Gr. Glabrous; the leaves narrower. (C. stellata, 

 Nutt.) Virginia, Kentucky, and southward. 



