220 COMPOSITE. (COMBOSITE FAMILY.) 



§ 1 . Corolla of -the ray amd disk ydhw ■: branches of the style tipped mth a pointed 

 or acute appmdage. 



# Achema mngless, wedge-oblong, flat, 2-awned or 2-toothed : scales of the outer invo- 

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

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

 the awns barbed upwardly.) 



■t-Says wanting. 



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

 natdy divided ; leaflets ovate-lanceolate, pointed, coarsely serrate ; heads panicu- 

 late-corymbed ; outer involucre of 3 - 5 foliaceous T)racts usually much longer than 

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

 — "Wet places, Ohio and southward. July - Sept. — Plant 1° - 2° high. 



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

 lanceolate4inear, cut-toothed, tapering into a petiole ; aums slender, upwardly 

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

 adelphia, Nuttall, — A very Obscure species. 



•1- -t- Bays conspicuous [golden-yeUow and showy), 



3. C trictiosperma, Michx. (Tickseed Sunflowek.) Smooth, 

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

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

 corymhose ; achenia narrowly wedge-oblong, bristly-ciliate above, crowned with 2 

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

 the coast. Scpti 



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

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

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

 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 vnnged, the narrowhj 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. tripteris, L. (Tall ConEOPSis.) Smooth; stem simple (4°- 

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

 ma. Less.) — Rich soil, 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 ^-divided, 

 therefore appearing as if when-led: pei'ennial (l°-3° high). 



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

 late entire leaflets, therefore appe^iring like 6 in a whorl : plant minutely soft- 

 pubescent. — Sandy woods, Vu'ginia and southward. July. 



"Var. stcllata, Torr. & Gr. Glabrous; the leaves naiTower. (C. stellata, 

 Null.) "V"irginia, Kentucky, and southward. 



