lOG COMroSIT/E. (COMPOSITK I'AMILV.) 



15. E. perfoliatum, L. l'ul)os(rnt or liiiiry ; leaves lanccohite, acumi- 

 nate, creiiate-scinite, iii<j;ost>, sessile and clasping at the iiase, or eonnat(>i)erfoIi- 

 atc ; heads al)Out lO-tlowered ; scales of the involucre linear-lanccolato, acme. 

 — Low ^Mouiid, Florida and northward. Sept. — Stem stout, 2° -3° hijjh. 

 Leaves C'-S' long. 



*-* *+ Leaves pfitiolcd. 



IC. E. sei'Dtinum, Miehx. Pubescent; stem tall, mostly hranchinj,' ; 

 leaves long-petioled, ovatc-lanecolate, acuminate, siiari)ly serrate, 3-rihhed ; 

 heads 12- 15-flowered ; scales, of the involucre lincar-oblonfr, obtuse; achenia 

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

 3° - 6° high. Leaves 4'- 9' long. 



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

 petioled, ovate, obtuse or mucronatc, 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 sliglitly cxscrted ; 

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

 rigid, I'-l^'long. 



* * * * Scales of the involucre {(jreen) rfjuul, in a sinrjle row: heads 8-30-floiv- 

 ered : leaves, uchaiia, ^x. not resinous<loUed : 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. — Ricli 

 shaded soil, Florida to Mississij)pi, and northward. Sept. — Stem commonly 

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



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

 est cordate, crcnatc-serratc, roughisli, on short petioles, barely acute ; heads 8 - 

 15-flowered; scales of the involucre linear; achenia smooth. (E. ccanothi- 

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

 1'- 2' long. Flowers white. 



20. E. incarnatum, Walt. Pubescent; stem .slender, reclining, diffu.sely 

 branched ; leaves on long petioles, deltoid, acuminate, truncate or coulate at tlie 

 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 2°-A° long. Leaves l'-2' 

 long. Flowers pale purple. 



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



21. E. fOBniculaceum, Willd. Stem tall, pubescent, paniculatcly much 

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

 of the involucre smooth, Tnargined, 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. ooronopifolium, Willd. Pubescent; stem panieulately branched; 

 divisions of the leaves linear ; heads crowded, 5-flowercd ; 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. 



