196 co.MPOsiT^. (composite family.) 



15. 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 10-flowered; scales of the involucre linear-lanceolate, acute. 

 — Low ground, Florida and northward. Si^'pt. — Stem stout, 2° - .3° high. 

 Leaves 6' -8' long. 



+-f ++ Leaves petiolcd. 



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

 leaves long-jjetioled, ovate-lanceolate, acuminate, siiarply serrate, 3-ribbed ; 

 heads 12-15-flowercd ; scales of tlie involucre linear-oblong, obtuse; achenia 

 smooth. — Rich soil, Florida to North Carolina, and wcsr^vard. Sept. — Stem 

 .3° - 6° high. Leaves 4'- 9' long. 



17. E. villosum, Swartz. Stem tomentose, branching ; leaves short- 

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

 ribbed ; corj-mb dense; heads 10 - 15-flowercd ; scales of the involucre about 

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

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

 rigid, I'-l^' long. 



* * * * Scales of the involucre (green) equal, in a single row: heads 8-SO-Jloiv- 

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



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

 acuminate, coarsely and siiarply serrate, 3-ribbed ; heads 10-20-flowercd ; 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. aromaticum, L. Pubescent; leaves thickish, ovate, or the low- 

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

 15-flowercd; scales of the involucre linear; achenia smooth. (E. ceanothi- 

 folium, ir/Wc/.)— Dry open woods, common. Sept.— Stem 2° high. Leaves 

 l'-2' long. Flowers white. 



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

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

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

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

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

 long. Flowers pale purple. 



(j 2. Heads in panicled racemes: leaves pinnately divided. 



21. E. fCEniculaceum, WiUd. 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. coronopifolium, Willd. Pubescent ; stem paniculately branched ; 

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

 lucre mucronate, pubescent, margined ; achenia smooth. ~ Dry sandy soil, 

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

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



