196 coMPOsiT^E. (composite family.) 



J 5. E. perfoliatum, L. Pubescent or hairy; leaves lanceolate, acumi- 

 nate, crenate-serrate, rugose, sessile and clasping at the base, or connate-perfoli- 

 ate ; heads about lO-flowered ; scales of the involucre linear-lanceolate, acute. 

 — Low ground, Florida and northward. Sept. — Stem stout, 2° - 3° high. 

 Leaves 6' - 8' long. 



++ ++ Leaves petioled. 



16. E. serotinum, Michx. Pubescent; stem tall, mostly branching ; 

 leaves long-pctioled, ovate-lanceolate, acuminate, sharply serrate, 3-ribbcd ; 

 heads 12 — 15-flowered ; scales of the involucre linear-oblong, obtuse; acbcniu 

 smooth. — Rich soil, Florida to North Carolina, and westward. Sept. — Stem 

 3° - 6° high. Leaves 4'- 9' long. 



17. E. viUosum, Swartz. Stem tomentose, branching ; leaves siiort- 

 pctioled, ovate, obtuse or mucronate, rusty-pubescent, denticulate or entire, 3- 

 ribbed; corymb dense; heads 10-15-fiowered; scales of the involucre about 

 10, equal, linear, obtuse, shorter than the flowers ; anthers slightly exserted ; 

 achenia hispid ; pappus shorter than the flowers. — South Florida. — Leaves 

 rigid, I'-l^' long. 



* * * * Scales of the involucre (greeJi) equal, in a single row : heads 8 - ZO-fiow- 

 ered : leaves, achenia, ^c. not resinous-dotted : leaves on slender petioles. 



18. E. ageratoides, L. Smooth; leaves thin, ovate or slightly cordate, 

 acuminate, coarsely and sharply serrate, 3-ribbed ; heads 10 - 20-flowered ; scales 

 of the involucre linear, acutish, slightly pubescent ; achenia smooth. — Rich 

 shaded soil, Florida to Mississippi, and northward. Sept. — Stem commonly 

 branching, 2° - 3° high. Leaves 3' - 5' long. Flowers white. 



19. E. aromaticuill, L. Pubescent; leaves thickish, ovate, or the low- 

 est cordate, crenate-serrate, roughish, on short petioles, barely acute ; heads 8 - 

 15-flowered I scales of the involucre linear; achenia smooth. {E..ceanothi- 

 folium, Willd.) — Dry open woods, common. Sept. — Stem 2° high. Leaves 

 l'-2' long. Flowers white. 



20. E. inearnatum, Walt. Pubescent; stem slender, reclining, diffusely 

 branched ; leaves on long petioles, deltoid, acuminate, truncate or coidate at the 

 base, coarsely seiTate ; corymbs numerous, small ; heads about 20-flowered ; 

 scales of the involucre linear, acute, 2-ribbed ; achenia hispid. — Rich shaded 

 soil, Florida to North Carolina. Sept. — Stem 2°-4° long. Leaves l'-2' 

 long. Flowers pale purple. 



§ 2. Heads in panicled racemes ; leaves pinnately divided. 



21. E. foeniculaeeum, Willd. Stem tall, pubescent, paniculately much 

 branched ; divisions of the leaves filiform, smooth ; heads 3 - 5-flowered ; scales 

 of the involucre smooth, margined, notched at the apex, mucronate ; achenia 

 smooth. — Chiefly in old fields, Florida to North Carolina, and westward. 

 Sept. and Oct — Stem 3°- 8° high. Flowers white. 



22. E. eoronopifolium, Willd. Pubescent ; stem paniculately branched ; 

 divisions of the leaves linear ; heads crowded, 5-flowered ; scales of the invo- 

 lucre mucronate, pubescent, margined ; achenia smooth. — Diy sandy soil, 

 Florida to North Carolina. Sept. and Oct. — Stem 2° - 4° high. Flowers 

 white. — Probably a broader-leaved form of the preceding. 



