COMPOSITAB (composite FAMILY) 853 



(i. Stems mostly leafy below, nearly naked above ; leaves variable ; 

 the lower ovate, obovate, or oblanceolate ; tbe upper much 

 reduced, often bract-like «. 

 «. rubescenco when present floccose-lanate and confined chiefly 

 to the base of the stem and to the leaf-axils f. 



/. Heads discoid ' . . . 1. S. disooideua. 



f. Heads radiate (except in 3, obovatus^ var. elonffattts) g. 

 g. Lower leaves obovate, occasionally subrotund or oblong; 



stolons when well developed slender and creeping . 8. S. obovatus. 

 g. Lower leaves subrotund to lanceolate ; the earliest leaves 

 cordate or subcordate, usually long-petioled ; stolons 

 short and stout, assurgent. 

 Basal leaves all broad-ovato, deeply cordate and relatively 



large 9. 5. awrms. 



Basal leaves mostly lanceolate ; only the earliest ones 



subrotund, cordate, and relatively small . . .10. S. Robbin&ii, 

 g. Lower leaves obiong-oblanceolate to fipatuiate, usually 

 narrowed gradually at the base ; the earliest i-arely 

 subrotund or oblong. 

 Stem but slightly woolly at the base, comparatively few- 

 headed 11. /S. BaUamiiat. 



Stem rather densely and permanently woolly at the base ; 



heads usually numerous 12. *5. SmaUii, 



«. Pubescence white-lanate and more or less persistent over stem 

 and leaves (rarely in no. 13 completely absent). 

 Basal leaves subrotund-ovate to oblong-lanceolate. 

 Stem-leaves deeply and irregularly divided . . .13. *S'. plattensia. 

 Stem-leaves usually dentate, not deeply divided, only a 



few at most lyrate 14. 5. tomentoaus. 



Basal leaves oblong-obovate, oblanceolate, or spatulate. 



Eastern species 15. xS. antenjnariifolius. 



Western species 16. ;S. canus. 



e. Pubescence of crisp-hirsute or subvillous hairs, not floccose 



or lanate, rarely quite glabrous ... . . 17. 5. integerrimua. 



u. Heads larger, 1.5-2 cm. high during anthesis . 18. ;S'. Paeudo-Arnica. 



\y 1. S. vulgXkis L. (Common Groundsel.) Low annual, 1-5 dm. high, 

 corymbosely branched, gldbrate, leafy to the inflorescence ; leaves pinnatifid 

 and toothed, 1-8 cm. long, 0.5-3 cm. broad ; calyeulate bracts (braoteoles) of 

 the involucre distinctly black-tipped ; rays none ; aohenes hirteUous. ■ — Waste 

 grounds, common. July-Sept. (Nat. from Eu.) 



2. S. Tiscdsos L. Coarser, 1.5-4 dm. high, viscid-pubescent and heavy- 

 scented ; leaves pinnatifid with toothed segments or 2-pinnatifid, 2-10 cm. long, 

 0.6-5 cm. broad ; calyeulate bracts (braoteoles) of the involucre not black-tipped ; 

 rays minute, bright yellow. — Waste grounds, coast of e. Que. to N. E.; also on 

 ballast near Philadelphia. Julj-Sept. (Nat. from Eu.) 



3. S. sylvAticus L. Stem erect, 1-7 dm. high, simple or branched, some- 

 what pubescent ; lower leaves petioled and more or less lyrate, the upper pin- 

 natifid with unequal lobes, sessile and sagittate at the clasping base, 2-15 cm. 

 long, 1-8 cm. broad ; inflorescence corymbose, naked or nearly so ; heads cylin- 

 drical ; involucre barely calyeulate ; ligules but slightly surpassing the disk- 

 flowers. — Clearings and waste places, Nfd. and e. Que. to Me., chiefly near the 

 coast ; also near Painesville, 0. July-Sept. (Nat. from Eu.) 



4. S. paliistris (L.) Hook. Annual or biennial, loosely villous to nearly gla- 

 brous ; stem stout, 2-7 dm. high ; leaves oblong-lanceolate, irregularly toothed 

 or Idc'iniate, the upper with a heart-shaped clasping base ; rays 20 or more, 

 short, pale yellow ; pappus copious and becoming very long. — Wet grounds, la. 

 top. Wise, N. Dak., and northw. June-Sept. (Eu.) 



5. S. glab^Uus Poir. (Buttek-weed.) Rather tall, 2-5 dm. or more high ; 

 leaves somewhat fleshy, lyrate or pinnately divided; divisions crenate or out- 

 lobed, variable ; heads less than 1 cm. high, in a naked corymbose inflorescence ; 

 rays 6-12, conspicuous. (S. lobatus Pers.) — Wet grounds, N. C. to oentr. 111., 

 Mo., and south w. March-June. 



6. S. JACOBAiiA L. (Stinking Willie.) Arachnoid-tomentulose to nearly 

 glabrous ; stem erect, 2-6 dm. or more high ; basal leaves somewhat lyrate ; 

 those of'the stem 2-3-pinnatisect, sessile, 2-:^ cm. long, 1-7 cm. broad; inflo- 

 rescence a many-headed corymbose cyme ; heads radiate. — Roadsides, pastures, 

 and ballast, Nfd. and e. Que. to Me., and locally to Ont. and N. J. July-Aug. 

 (Nat. from Eu.) 



