COMPOSITAK (COMPOSITE FAMILY) 835 



4- - * Leaves narrow, the np^fnnnst alternate, not ^-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 l>ase. 

 chiefly alternate, yrei'ii both sides, somewhat scabrous, finely and sparingly 

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

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

 O. {Keller man). 



13. H. grosseserratus Martens. Stem 2-3 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. Dalyi Britton?) Low thickets and swamps, w. N. K. 

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

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

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

 north westw. 



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

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

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

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

 wan to Tex. ; occasionally adventive eastw. 



---->-(- Leaves all or most of them opposite, 3-nerved (faintly in no. 17). 



++ Heads very small (about 8 mm. broad} ; rays 6-8 ; bracts few, short, irregu- 

 I iii-lii imbricated, the outer with spreading foliaceous pointed tips; stems 

 smooth. 



16. H. microcSphalus 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. parviflorus 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. 



-M- ++ 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, 

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

 O. to Mo. 



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

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

 3-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 narrowly 

 lanceolate, attenuate, ciliate, equaling the disk (I 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, very rough above, usually rough 



