COMPOSITE. (COMPOSITE FAMILY.) 241 



involucre leaf v, imbricated in several rows; the innermost smallest, chaff like. 

 Receptacle small, with linear acutish chaff. Acheuia round or obovate, flat, 

 broadly winged, 2-toothed or emarginate at the apex. Pappus none, or repre- 

 sented by the two teeth of the acheuia. Tall resiuous herbs, with alternate 

 opposite or whorled leaves, and large heads of yellow flowers. 



* Stems terete, nearly naked : leaves alternate ; the lowest large, serrate or vari- 

 ously lobed, long-petioled ; the others small and scattered. 



1 . S. laciniatum, L. Stem hispid or smooth ; leaves very rough or his- 

 piil, with clasping petioles, piuuately parted; the divisions oblong or lanceo- 

 late, acute, lobed or toothed ; heads large, spicate or racemose ; scales of the 

 involucre ovate, tapering into a long and spreading point, ciliate ; acheuia 

 round-obovate, emarginate. Varies with the more numerous sessile and 

 clasping leaves less deeply parted. (S. gummiferum, Ell.) Prairies of Ala- 

 bama, and westward. July - August. Stem 6 -8 high. Lowest leaves 

 1- 2 long. Heads 14-'- 2' in diameter. 



2. S. terebinthinaceum, L. Stem smooth, naked above ; leaves 

 rough-hairy, undivided, cordate-oval or oblong, coarsely serrate, on slender 

 petioles; heads loosely panicled ; scales of the involucre oval or obovate, 

 obtuse, smooth; achenia obovate, emarginate or 2-toothed. (S. piimatiti 

 dnm, ZJ//., leaves pinnatiiid.) Open woods in the upper districts of Georgia, 

 and westward. July -Sept. Stem 4-8 high. Radical leaves 2 long 

 Heads 1' wide. 



3. S. compositum, Michx. Smooth; leaves cordate-ovate or reniform, 

 angularly toothed or variously lobed, long-petioled ; heads small, orymbosely 

 panicled ; scales of the involucre obovate or oblong, obtuse ; acheuia roundish, 

 deeply emarginate; rays - 10. Sandy open woods, Florida to North Caro- 

 lina. July - Sept. Stem 3-6 high. Leaves 6'- 12' long. Heads \' in 

 diameter. 



* * Stems leafy : leaves undivided, alternate, opposite, or whorleJ. 



- Stems terete. 



4. S. trifoliatum, L. Stem smooth ; leaves rough, lanceolate, slightly 

 serrate, on short bristly petioles ; the upper alternate or opposite ; the lower 

 3-4 in a whorl; heads small, loosely panicled; scales of the involucre ovate 

 or oval, fringed on the margins; achenia oblong-obovate, 2-toothed. Open 

 woods along the mountains of Georgia, and northward. July -Sept. Stem 

 4 6 high. Leaves 4' - 6' long. 



5. S. Asteriscus, L. Stem smooth or hirsute ; leaves rough, opposite or 

 alternate, or the lower sometimes 3 in a whorl, lanceolate or oblong, toothed, 

 on short hirsute petioles; the upper sessile and commonly entire; heads 

 somewhat corymbose, rather large; exterior scales of the involucre ovate, 

 acute, short-ciliate ; the interior oblong, obtuse; achenia broadly obovate, 2- 

 toothed. Var. DENTATU.M. Lower leaves on rather long petioles, sometimes 

 incisely toothed ; achenia slightly emarginate at the apex. (S. deutatum, 

 Ell.} Dry open wnods, Florida to North Carolina. July -Sept. Stem 

 2-4 c high. Leaves 3' - 5' long. Rays sh"wv. 



