COMPOSITAE (COMPOSITE FAMILY) 835 



■*--•-•»- Leaves narrow^ the uppermost alternate, not S-nerved, scabrous both 

 sides; heads rather small ; bracts loose, attenuate. 



++ Stem smooth and glaucous. 



12. H. Kellermani Britton, Slender, leafy, paniculately branched above ; 

 leaves narrowly lance-linear to linear^ attenuate to the apex and subsessile base, 

 chiefly alternate, green both sides, somewhat scabrous, finely and sparingly 

 serrate ; heads numerous, 3-4.5 cm. wide ; involucral bracts lance-linear, sub- 

 equal, about 1 cm. long; rays golden-yellow, 1-2 cm. long. — Near Columbus, 

 O. (Keller man). 



IS. H. grosseserratus Martens. Stem 2S m. high ; leaves elongated-lanceo- 

 late or ovate-lanceolate, taper-pointed, sharply serrate or denticulate, acute or 

 attenuate at base, petioled, often whiter and finely pubescent beneath ; bracts 

 lance-awl-shaped, slightly ciliate. — Dry plains, w. Me. to N. J., westw. to Ont. , 

 Dak., and Tex. — Probably runs into the next. 



++ ++ Stem hairy or scabrous. 



14. H. giganteus L. Stem 0.5-3 m. high, branched above ; leaves lanceolate, 

 pointed, minutely serrate or nearly entire, green both sides, narrowed and ciliate 

 at base, but nearly sessile; bracts long, linear-lanceolate, pointed, hairy or 

 strongly ciliate. {H. Da.lyi Britton'?) — Low thickets and swamps, w. N. E. 

 to Ont., westw. and soutliw. — Heads somewhat corymbed; the pale yellow rays 

 15-20; roots often becoming tuber-like, especially in var. subtuber^sus (Bour- 

 geau) Britton which has mostly opposite leaves, and occurs from n. Mich. 

 north westw, 



15. H. Maximiliani Schrad. Resembling the preceding ; stout, often simple, 

 0.5-3 m. high ; leaves becoming rigid and very scabrous, entire or sparhigly den- 

 ticulate ; heads rather large, usually short-peduncled, teiTninal and in the upper 

 axils ; bracts longer-attenuate, more rigid. — Prairies, Minn, and the Saskatche- 

 w'an to Tex. ; occasionally adventive eastw. 



■*- -t- -*- -I- Leaves all or most of them opposite, o-nerved (faintly in no. 17). 



++ Heads very small (about 8 mm. broad); rays 5-8; bracts few, short, irregii- 

 larly imbricated, the outer with spreading foliaceous pointed tips; stems 

 smooth. 



16. H. microcephalus T. & G. Stem 1-2 m. high, with numerous slender 

 branches above ; leaves thin, ovate-lanceolate, taper-pointed, somewhat serrate, 

 petioled, rough above, pale and puberulent beneath ; peduncles slender, rough ; 

 bracts ovate and ovate-lanceolate, ciliate. (H. parvijlorus Bernh., not HBK.) 

 — Thickets, etc.. Pa. and "s. Mich." to Mo., and southw. 



17. H. laevigatus T. & G. Stem slender. 0.5-2 m. high, simple or sparingly 

 branched, glaucous, glabrous throughout, as well as the slightly serrate lanceo- 

 late leaves which are usually narrow and attenuate to the base. — Dry soil, 

 Allegheny Mts., Va., and southw. 



++ ++ Heads larger ; rays usually over 10 ; spreading by creeping rootstocks. 

 = Leaves sessile or subsessile to short-petiolate, serrulate or entire. 



18. H. doronicoides Lam. Finely pubescent and roughish, 1-3 m. high ; 

 leaves sessile, ovate-oblong, acute, triply-nerved above the broadly cuneate base, 

 serndate; bracts loose, attenuate, mostly 1-1.5 cm. long, hairy. — Dry ground, 

 O. to Mo. 



19. H. divaricatus L. Stem simple or forked and corymbed at the top, 0.5- 

 2 m. high, smooth below ; leaves all opposite and divaricate, ovate-lanceolate, 

 S-nerved from the rounded or truncate sessile base, tapering gradually to a sharp 

 point, 0.5-2 dm. long, serrate, thickish, rough both sides; bracts nan-owly 

 lanceolate, attenuate, ciliate, equaling the disk (1 cm. wide); rays 8-12, 2.5 cm. 

 long. — Thickets and barrens, s. Me. to L. Winnipeg, Neb., and southw. 



20. H. hirsutus Raf. Stem simple or forked above, stout, 0.5-1 m. high, 

 bristly-hairy ; leaves all short-petioled, ovate-lanceolate, gradually pointed^ 

 slightly serrate, rounded or obtuse at the base, vei'y rough above, usually rough- 



