COMPOSITE FAMILY. 233 



S. Iatif61ia, Linn. Stem angled and zigzag; leaves broadly ovate, 

 strongly si-rrate, pointed both ends ; rays 3-4. N. and S. 



S. Curtisii, Torr. & (iray. Stem angled ; leaves oblong or long- 

 lanceolate, with narrow, entire ba.se, toothed above ; clusters loose ; rays 



4-7. Va., S. o 7 ., 



= = Akenes glabrous. 



S. bfcolor, Linn. Gray-hairy, strict ; leaves oblong or elliptic, some- 

 what serrate ; upper clusters spicate or nearly panicled ; involucral scales 

 very obtuse ; rays 5-14, cream-color. N. and S. 



S. monticola, 'I'orr. & Gray. Nearly glabrous ; leaves oblong-ovate 

 or narrower, the lower sparingly serrate ; scales acutish ; rays yellow, 

 5-0. Md., S. 



■M- ++ Heads ill a compuund terminal corymb, not at all axillary or 



racemose. 



= Leaves folded and n curved. 



S. Ridd^Uii, Frank. Smooth, 2°-4°, very leafy ; leaves long linear- 

 lanceolate, those on the stem mostly clasping ; heads 20-30-llowered, very 

 numerous. Grassy lands, Ohio, W. and S. 



= = Leaves flat. 



S. rigida, Linn. Rough, somewhat hoary, 2°-5°, very leafy ; leaves 

 oval or oblony, thick ; heads large, 30- or more-flowered ; rays 7-10. N. 

 Eng., S. and W. 



S. Ohioensis, Riddell. A^'ery smooth, 2°-3°, leafy ; stem leaves 

 oblong-lanceolate, the radical ones elongated and with margined petioles ; 

 head l()-20-flowered ; rays 6-7. W. N. Y., W. 



++■*-*++ Heads in a terminal panicle, or sometimes in a thyrse, small or 

 middle-sized. 



= Leaves painly ?j-ribbed ; heads in \-sided sprays. 



II Both stem and leaves smooth and glabrous {or stem roughish only 



above). 



o Leaves firm, thickish; outer involucral scales short and ovate, the inner 

 oblong-linear, all obtuse. 



S. Missouriensis, Nutt. Smooth, l°-3° ; leaves linear-lanceolate or 

 the lower broader ; clusters of heads racemose in a short and broad, 

 rather open panicle ; akenes nearly glabrous. Wis., S. and W. 



S. Sh6rtii, 'i'orr. & Gray, lioughish above ; leaves oblong-lance- 

 olate ; panicle short and crowded ; akenes pubescent. S. O. and 8. W. 



o o Leaves thinnish ; scales linear, obtuse. 



S. Leaven-wrdrthii, -Torr. & Gray. Strict and rigid, 2°-4°, scabrous 

 or i)ul)fruient above ; teaves mostly linear, sharply and finely serrate ; 

 panicle luuLr and open ; rays 10-12, small. S. C, S. 



S. ser6tina. Ait. Stout, 2'^-7^, smooth and sometimes glaucous; 

 leaves lauccDJate and taper-pointed, serrate and ciliate, smooth; rays 

 7-14, rather long. N. and S. 



\'ar. gigantfea, Gray. Leaves pubescent, the lateral ribs more promi- 

 nent. Same range. 



II II Stem and generally the leaves prominently pubescent or scabrous (S. 

 scrotina, var. gigantea, above, may be sought here). 



o riant green. 



S. Canadensis, Linn. Hough-hairy, stout, 2P-C)° ; leaves lanceolate 

 and pointed, serrate or sometimes almost entire, pubescent beneath and 



