196 COMPOSITA. (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. Sept.— Stem stout, 29 - 39 high. | 
Leaves 6! - 8' long. ; 
: ++ ++ Leaves petioled. 
16. E. serotinum, Michx.  Pubescent; stem tall, mostly branching; ' 
leaves long-petioled, ovate-lanceolate, acuminate, sharply serrate, 3-ribbed ; 
heads 12—15-flowered ; scales of the involucre linear-oblong, obtuse; achenia 
smooth. — Rich soil, Florida to North Carolina, and westward. Sept. — Stem 
39-6? 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 ; corymb dense; heads 10-15-flowered ; 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, 1 - 14! long. | 
* * * * Scales of the involucre (green) equal, in a single row: heads 8 — 30-flow- 
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 — 90-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. aromaticum, L. Pubescent; leaves thickish, ovate, or the low- 
est cordate, crenate-serrate, roughish, on short petioles, barely acute; heads 8- 
15-flowered ; scales of the involucre linear; achenia smooth. (E. ceanothi- 
folium, Willd.) — Dry open woods, common. Sept.— Stem 2° high. Leaves 
1'-2'long. Flowers white. 
20. E. incarnatum, Walt. Pubescent; stem slender, reclining, diffusely 
branched ; leaves on long petioles, deltoid, acuminate, truncate or cordate at the — 
base, coarsely serrate ; 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 20-40 long. Leaves xs 
long. Flowers pale purple. Ho 
x E BEP: $2. Heads in panicled racemes : leaves pinnately divided. 
. 8L E. feeniculaceum, 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. 
