196 coMrusiT.i:. (co.mi'Ositk iamily.) 



15. E. perfoliatum, L. Pulu'scent or hairy; Iciivos luiuvohitc, atumi- 

 uate, crcnate-serrate, rugose, sessile and clasping at the base, or connatc-pcrfoli- 

 ate ; heads about 10-flowered; scales of the involucre linear-lanceolate, acute. 

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

 Leaves C'-S' long. 



*+ -w- Leaves pcliolcd. 



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

 leaves lonL;-])ciioUil, ovate-lanceolate, acuminate, sharjjly serrate, 3-ribbed ; 

 heads 12 - 15-(lowercd ; scales of the involucre linear-oblong, obtuse; achenia 

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

 3° - 0° high. Leaves 4'- 9' long. 



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

 pctiolcd, ovate, olttuso or mucrouatc, rusty-pubescent, denticulate or entire, 3- 

 ribbcd ; corymb dense; heads 10 - 15-flowered ; scales of the involucre about 

 10, equal, linear, obtuse, shorter than the flowers; anthers slightly e.xscrtcd ; 

 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 - 30-Jiow- 

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



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

 acuminate, coarsely and sharplj' 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-scrratc, roughish, on short petioles, barely acute ; heads 8 - 

 1.5-flowercd ; scales of the involucre linear ; achenia smooth. (E. ccanothi- 

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

 1'- 2' long. Flowers white. 



20. E. incarnatum, Walt. Pubescent ; stem slender, reclining, difi'uscly 

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

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

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

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

 Ibiig. Flowers pale jiurplc. 



§ 2. Heads in panicled racemes : leaves pinnalcltj dividid. 



21. E. foeniculaceum, Willd. Stem tall, pubescent, ])ani(ulately much 

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

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

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

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



22. E. COronopifolium, Willd. Pnln'sccnt ; stem paniculatcly liranched ; 

 divisions of the V-.iw. linear; heads crowded, .Vflowered ; scales of the invo- 

 lucre mucronate, puliesccnt, margine<l ; achenin smooth. — Dry sandy soil, 

 Floriila tw North Carolina. Sept. and Oct. — Stem 2<»-4°high. Flowcri 

 white. — Probably a broader-leaved form of the pri'ddiiig. 



