COMPOSITAE 331 



I. F. / 388^. ) In dry or stony soil, N. J. and eastern Pa. to N. C. — Penn- 

 sylvania : Db;i,aware ; Chester ; I,ancaster ; IvEbanon. 



5. Rudbeckia speolosa Wenderoth. Showy CoNE-Fi<owER. (Man. 

 p. 987 ; I. F. / 388g.) In moist soil, N. J. to Mich., south to Ala. and 

 Ark. — Pennsylvania : Phii<adEI<phia, on the Wissahickon ; CHESTER. 



6. Rudbeckia laciniata L. Tale CoNE-ELOWER. (Man. p. 988; I. 

 F. /. sSgo.) In moist thickets, Quebec to Man. and Mont., south to 

 Fla., Kans. and N. Mex. — Pennsylvania: Northampton; Bucks; 

 Chester ; Lancaster ; York ; Frankein ; Erie ; Aeeegheny. 



31. HELIANTHUS L. 



Disk purple, purplish or brown. 

 Perennial plants : disk convex. i. H. angusiifolius. 



Annual plants : disk flat or nearly so. 

 Bracts of the involucre ovate, hispid and ciliate : leaf -blades toothed. 



2. H. annuus. 

 Bracts of the involucre lanceolate, canescent : leaf-blades entire or nearly 

 so. 3. H. petiolaris. 



Disk yellow or yellowish. 

 Leaf-blades prevailingly of a lanceolate type, sometimes elongated. 

 Involucre less than 10 mm. thick : leaf-blades thin. 4. H. microcephalus . 

 Involucre over 10 mm. thick : leaf-blades relatively thick. 

 Stem scabrous to hispid. 

 Leaf -blades scabrous above, hirsute beneath. 5. H. giganleus. 

 Leaf-blades scabrous on both sides. 6. H. Maximilianii. 



Stem smooth and glabrous. 

 Leaf-blades narrowly lanceolate, narrowed into petiole-like bases. 



7. H. grosse-serralus. 

 Leaf-blades broadly lanceolate, sessile or nearly so by the truncate or 

 subcordate base. 8. H. divaricalus. 



Leaf-blades prevailingly of an ovate or ovate-lanceolate type. 

 Leaf -blades sessile or nearly so. 

 Stem glabrous : leaves spreading. 8. H. divaricatus. 



Stem densely pubescent : leaves ascending. 9. H. mollis. 



Leaf-blades petioled or narrowed into petiole-like bases. 

 Stem glabrous or merely puberulent. 

 Leaf-blades membranous, markedly toothed, slender-petioled. 



10. H. decapetalus. 

 Leaf-blades firmer; shallowly toothed or entire, short-petioled. 



Bracts of the involucre much longer than the disk. 



11. H.tracheliifolius. 

 Bracts of the involucre about as long as the disk. 



12. H. slrumosus. 

 Stem hirsute, hispid or scabrous-pubescent. 



Leaf-blades rounded or truncate at the base, short-petioled. 



13. H. hirsutus. 

 Leaf-blades, at least those of the upper leaves, narrowed at the base, 



relatively long-petioled. 14. H. iuberosus. 



1. Helianthus angustifoliua L. Narrow-eeavED SunFEOWER. 

 (Man. p. 991 ; I. V.f. 38^8.) In swamps, southeastern N. Y. to Fla., Ky. 

 and Tex., but mainly near the coast. — Pennsylvania: Bucks, Tullytown. 



