COMPOSITAE (COMPOSITE FAMILY) 795 



blunt; rays 6-13. small; achenes nearly glahroiis. — Dry prairies and open 

 woods, Tenn. to Man., and westw. July-Sept. 



86. S. Gattingeri Chapm. Slender and strict, 4-10 dm. high ; stems smooth 

 throughout; leaves ciliolate, smooth beneath, harsh above, the lowe.st 0.7-1.5 

 dm. long, lance-spatulate, appressed-serrulate or subf^ntire, the upper reduced 

 rapidly to minute entire bracts xcith naked axils; branches of the naked subco- 

 rymhiforrn panicle elongate and ascending^ hardly recurved; involucre 3-4 mm. 

 long, its oblong bracts obtuse ; rays 6-10 ; achenes ajpressed-piiberulent, or 

 glabrate below. — Limestone hills and barrens, Tenn. and Mo. July-Sept. 



— = Branches of the panicle pubescent. 



a. Leaves firm and often rigid, the loicer usually elongated and many times ex- 

 ceeding the reduced upper ones (except in no. 39); involucral bracts thick 

 and rigid. 



1. Lower portion of the stem and the leaves essentially glabrous. 



37. S. Sh6rtii T. & G. Stem slender, simple. 0.5-1.2 m. high, minutely 

 roughish-pubescent above ; leaves (the larger 0.5-1 dm. long) oblong-lanceolate. 

 acute, the lower mostly serrate with a few fine teeth ; racemes recurved, usually 

 in a crowded panicle ; involucre slender^ 4-6 mm. long ; achenes silky-pubescent. 

 — Rocks at the Falls of the O. 



2. Stem and leaves pubescent. 



o Stems and leaves ashy or whitish icith close puberidence. 



38. S. nemoralis Ait. Clothed with minute grayish-hoary soft or roughish 

 pubescence ; stem simple or corymbed above. 1.5-7.5 dm. high; leaves oblan- 

 ceolate or spatulate-oblong, mostly subtending axillary fascicles ; the lower long- 

 petioled, usually crenate-toothed, 5-15 cm. long; the uppermost greatly reduced, 

 1-3 cm. long ; racemes numerous, dense, at length recurved, and ordinarily form- 

 ing a ci'oicded compound raceme or panicle which is turned to one side; invo- 

 lucre 3.5-6 mm. long, its firm yellowish bracts linear-oblong, appressed ; rays 

 5-9, bright yellow. — Dry open soil (rarely in woods), P. E. I. to the Saskatche- 

 wan, and southw. July-Nov. (rarely Dec). 



39. S. mollis Bartl. Stout, rigid, canescent ; the stems 1.5-5 dm. high, soli- 

 tary or clustered from r freely stoloniferous snbligneous base ; leaves rigid, oval 

 or oblong, obtuse or rarely acutish, gradually reduced upward, the uppermost 

 1-3 cm. long, the lower 3-8 cm. long ; racemes ascending in a dense thyrse ; 

 involucre 4-6 mm. long, greenish-yellow. (*S'. nemoralis., var. incana Gray.) — 

 Dry hills and plains, Man. and Minn., westw. and southw. July-Sept. (Mex.) 



o o Stems and leaves green. 



40. S. radula Xutt. Stem and oblong or obovate-spatulate leaves rigid and 

 very rough, not hoary., the upper leaves sessile ; bracts oblong, rigid ; rays 3-6 ; 

 otherwise nearly as in no. 39. — Limestone bluffs and dry open soil, s. w. 111. to 

 w. La. and Tex. Aug. -Oct. 



h. Leaves thinner., essentially uniform from base to summit of the stem; invO' 



lucral bracts thin. 



1. Leaves elongate, linear to lance-oblong. 



o Involucre 2-2.8 mm. long. 



41. S. canadensis L. Stem rather slender, 0.3-1.5 m. high, glabrous at least 

 below, often minutely pubescent above ; leaves narrowly lanceolate, thin, gla- 

 brous above, minutely pubescent on the nerves beneath, mostly sharp-serrate, the 

 middle ones 6-13 cm. long, 5-18 mm. wide ; heads tiny, crowded in recurved 

 racemes and forming dense broadly pyramidal panicles ; pedicels strongly pilose ; 

 involucral bracts linear, mostly attenuate, greeni.sh-straw-color. (Var, glabrata 

 Porter.) — 7'hickets and rich open soil, Nfd. to N. Dak., s. to W. Va. and Ky. 

 July-Sept. 



Var. gilvocanescens Rydb. Stems and leaves cinereous or canescent with 

 minute puberulence; leaves broadly lanceolate to lance-oblong, the middle ones 



