234 COMPOSITE FAMILY. 



rough above ; heads small and rays very short. Common and variable. 

 ST. and S. 



S. radula, Nutt. Stem and leaves very rough; leaves oblong or 

 obovate-spatulate. 111., W. and S. 



o o Plant ashy-canescent. 



S. nemoralis, Ait. Pubescence close ; stem nearly simple, less than 

 3° ; leaves oblanceolate or spatulate-oblong, the lower obscurely crenate ; 

 panicle becoming secund or one-sided; rays 6-9, light-colored. Sterile 

 soil, N. and S. 



= = Leaves either not at all Z-ribbed, or very obscurely triplinerved. 



II Leaves all perfectly entire. 



S. sempe'rvirens, Linn. Smooth and stout, l°-8° ; leaves lanceolate 

 and slightly clasping, very smooth, the lowest ones obscurely 3-nerved ; 

 heads rather large and showy, the 7-10 rays golden. Seashore, N. B. to 

 Fla. Flowers early. 



S. oddra, Ait. Smooth or nearly so, 2°-3°, the stem slender and 

 sometimes reclined ; leaves not 3-nerved, linear-lanceolate, shining and 

 pellucid-dotted ; heads very small ; rays 3-4, rather large. Canada to Fla. 



II || Some of the leaves more or less crenulate or serrate (except sometimes 



thefirsf). 



o Panicle thyrsoid, pyramidal or long-virgate. 



x Scales thin, acute. 



S. stricta. Ait. Very smooth, with small, appressed, entire, lance- 

 oblong, thickish leaves, the upper ones mere bracts ; heads in a narrow 

 spicate raceme ; rays 5-7. Pine barrens, N. J., S. 



S. pube'rula, Nutt. Minutely hoary ; leaves lanceolate-acute ; heads 

 very numerous in short racemes which form a long dense panicle ; rays 

 about 10. Me., S. *« Scales firm, obtuse. 



S. uligin6aa, Nutt. Smooth, 2°-3° ; leaves lanceolate, tapering into 

 a winged petiole ; racemes much crowded into a dense wand-like panicle ; 

 rays 5-6, small. Bogs, N. 



S. apecidsa, Nutt. Smooth, 3°-6° ; leaves rather thick, rough-mar- 

 gined, oval or ovate, or the uppermost oblong-lanceolate ; heads in 

 numerous erect racemes, which form a pyramidal panicle ; rays about 5, 

 large. Can. to N. C. and W. 



o o Panicle short and broad or racemose. 



x Leaves linear or lanceolate, sessile (on the stem), obscurely veiny; 

 heads in a short and broad panicle of secund clusters. 



S. tortildlia, Ell. Stem 2°-3°, scabrous-pubescent; leaves linear, 

 generally twisted ; rays very short. Va., S. 



S. pil6sa, Walt. Stout, 3°-7°, with spreading hairs ; leaves oblong- 

 lanceolate or ovate-lanceolate, hairy beneath ; rays 7-10, very short. 

 Pine barrens, N. J., S. 



x x Leaves broad or ample, veiny ; heads racemosely paniculate. 



+ Foliage rugose-veiny, pubescent or scabrous above or below. 



S. patula, Muhl. Stem strongly angled, smooth, 2°-4° ; leaves ovate, 

 very rough above, smooth and veiny beneath ; racemes rather short and 

 numerous. Can. to Ga. and Tex. 



S. amplexicaulia, Torr. & Gray. Slender, l°-3°, more or less pubes- 

 cent; leaves ovate, acute, scabrous above and soft-pubescent beneath, 

 clasping ; rays about 3 (sometimes 0). Fla., W. 



