212 COMPOSITE. (COMPOSITE FAMILY.) 



Var. strietula, Torr. & Gray. Stem simple, or with few elongated rough- 

 pubescent branches ; leaves smaller ; racemes short, forming a long and slender 

 compound raceme. (S. salicina, Ell.) Swamps, Florida, and northward. 

 Sept. and Oct. Stem 4 - 6 high. 



24. S. arguta, Ait. Smooth ; leaves sharply serrate, acute or acuminate 

 at each end, the lowest elliptical or lanceolate-oblong, somewhat 3-ribbed, on 

 winged and ciliate petioles ; the upper sessile ; panicle dense, somewhat corym- 

 bose ; heads small, crowded, 1 8 - 20-flowered ; rays 8-12, small; scales of the 

 involucre obtuse ; achenia nearly smooth. (S. juncea, Ait., a form with narrower 

 and less strongly serrate leaves, the upper ones entire.) Rich soil in the upper 

 districts. Sept. Stem 2 - 4 high. 



25. S. Boottii, Hook. Stem smooth, or pubescent above ; leaves lanceo- 

 late or oblong, acute or acuminate at each end, appressed-serrate, smooth or 

 more or less pubescent; panicle open, oblong or pyramidal; heads about 12- 

 flowered ; rays 5 ; scales of the involucre obtuse ; achenia nearly smooth. Va- 

 ries, with longer, narrower, and more sharply serrate leaves, and slender racemose 

 panicles towards the summits of the spreading branches. ( S. juncea ? Ell. ) 

 Sandy soil, Florida to North Carolina. Sept. Stem" 2 -3 high, often pur- 

 plish. Heads larger and leaves more rigid than in the last. 



26. S. gracillima, Torr. & Gray. Smooth ; stem slender ; lowest leaves 

 spatulate-lanceolate, obtuse, serrate near the apex ; the others linear and entire ; 

 heads rather large, 9- 12-flowered, forming a narrow compound raceme at the 

 summit of the stem and branches ; rays mostly wanting ; scales of the involucre 

 oblong, obtuse ; achenia pubescent. Dry pine barrens, Middle Florida. Oct. 

 Stem 2 high. 



*- -i *- Leaves very numerous, gradually diminishing in size upward, veim/, sessile, 

 or the lowest narrowed into a short petiole : heads small. 



27. S. altissima, L. Stem hirsute ; leaves ovate or oblong, acute, serrate, 

 rough above, pubescent, especially on the veins beneath, often rugose, promi- 

 nently veined ; panicle leafy, often narrow and elongated ; the racemes slender 

 and recurved ; scales of the 10- 15-flowcred involucre linear; rays 6-9, small; 

 achenia pubescent. (S. rugosa, S. ulmifolia, and S. aspera, Ell.) Low thick- 

 ets, Florida, and northward. Sept. and Oct. Stem 2 -6 high, commorilv 

 branching. Leaves variable in texture and pubescence, being thin and smoother 

 in shady places, and more rigid, rougher, and often rugose in places more ex- 

 posed. 



28. S. Ulmifolia, Muhl. Stem smooth, or softly pubescent above ; leaves 

 ovate-lanceolate, acuminate, serrate, smooth on the upper surface, paler and pu- 

 bescent on the veins beneath ; panicle loose, spreading ; heads about 10-flowcred ; 

 rays 4-5; scales of the involucre acutish ; achenia nearly smooth. Low 

 ground in the upper districts of Alabama, and northward. Sept. Stem 2 - 3 

 high. Leaves thin, 2' 3' long. 



29. S. Elliottii, TOIT. & Gray. Smooth ; stem mostly simple ; leaves 

 oblong-lanceolate or elliptical, sessile, acute, finely serrate, the upper often 

 entire; racemes crowded, forming a pyramidal panicle; scales of the 13-20- 



