CAKDUACEAE 1269 



late to oblong-lanceolate, attenuate, ciliate, the tips more or less spreading, the inner ones 

 scarcely dilated, rather abruptly contracted below the middle : ray-flowers 11-15 ; ligules 

 bright yellow, 2.5-4 cm. long : disk 1.5-2 cm. wide. 



In dry woods and on shaded banks, Maine to Ontario and Minnesota, Georgia and Arkansas. 



33. Helianthus Schweinitzii T. & G. Perennial, deep green. Stems 4-18 dm. 

 tall, branched, scabrous and hispidulous : leaves opposite below, alternate on the upper 

 part of the stem ; blades firm, lanceolate or linear-lanceolate, attenuate, serrulate or nearly 

 entire, shagreen above, canescent beneath : heads relatively small : involucral bracts linear- 

 lanceolate to lanceolate, acuminate, hispid : ray-flowers 9-13 ; ligules yellow, 2-2.5 cm. 

 long : disk becoming about 1.5 cm. broad. 



In dry soil, North Carolina to Georgia and Alabama. 



34. Helianthus cinereus T. & G. Perennial, minutely dull cinereous-pubescent. 

 Stems 3-6 dm. tall, mostly simple : leaves opposite, mostly near the middle of the stem ; 

 blades leathery, elliptic to elliptic-lanceolate, 2-8 cm. long, acute, serrulate, narrowed at 

 the base, but sessile : heads showy : involucral bracts lanceolate or oblong-lanceolate, 8-12 

 mm. long, attenuate : ray-flowers 11-16 ; ligules yellow, 2-2.5 cm. long : disk yellow, 1.5- 

 1.8 cm. broad. 



In dry soil, Texas. Summer. 



35. Helianthus tomentosus Michx. Perennial, pubescent. Stems 9-30 dm. tall, 

 scabrous to hispid, branching above : leaves mostly alternate ; blades ovate to lanceolate, 

 1-3 dm. long, acute or acuminate, undulate or shallowly toothed, narrowed into winged 

 petioles: heads showy: involucral bracts linear-lanceolate, 1.5-2 cm. long, acuminate, 

 bristly, the outer ones spreading or recurved : ray-flowers numerous ; ligules bright yellow, 

 2.5-3 cm. long : disk yellow, 2-2.5 cm. broad. 



On hillsides, Virginia to Georgia and Alabama. 



36. Helianthus tuberosus L. Perennial, pubescent. Stems 6-30 dm. tall, sca- 

 brous to hirsute, often branching above : leaves mostly alternate ; blades thickish, ovate to 

 lanceolate, 8-20 cm. long, acuminate, more or less serrate, cuneate to subcordate at the 

 base, commonly pubescent beneath, scabous above, terminating petiole-like bases : heads 

 showy : involucral bracts rather foliaceous, linear to linear-lanceolate, 1.5-2.5 cm. long, 

 ciliate, long-attenuate, often pubescent on the back : ray-flowers numerous ; ligules bright 

 yellow, 2.5-4 cm. long : disk yellow, 1.5-2 cm. broad. 



In alluvial soil, New Brunswick and Ontario to the Northwest Territory, Georgia and Arkansas. 



37. Helianthus doroconoides Lam. Perennial, pubescent all over. Stems 1-2 m. 

 tall, sparingly branched above, softly pubescent : leaves opposite on the lower part of the 

 stem, alternate above ; blades leathery, ovate to ovate-lanceolate, 1-3 dm. long, about 

 equally scabrous-pubescent on both sides, acute or slightly acuminate, shallowly serrate, 

 sessile : heads showy : involucral bracts linear-lanceolate to lanceolate, attenuate his- 

 pidulous and ciliate, the inner about 1 cm. long: ray-flowers 11-19; ligules 2.5-4 cm. 

 long : disk yellow, about 1.5 cm. broad. 



In dry soil, Michigan to Ohio, Missouri and Arkansas. 



38. Helianthus Maximilian!! Schrad. Perennial, scabrous-hispidulous. Stems 6- 

 36 dm. tall, usually branched above : leaves mostly alternate ; blades firm, lanceolate, 

 varying to linear or oblong-lanceolate, 8-15 cm. long, acute or acuminate at both ends, en- 

 tire or denticulate, the lower ones narrowed into petiole-like bases : heads showy : involu- 

 cral bracts gray-pubescent, linear-lanceolate to lanceolate, 1.5-2.5 cm. long, each attenuate 

 into a slender tip: ray-flowers 15-30; ligules golden yellow, 2.5-3.5 cm. long: disk 

 1.5-2 cm. broad. 



On plains and prairies, Manitoba and the Northwest Territory to Minnesota and Texas. 



39. Helianthus giganteus L. Perennial, scabrous or hispidulous. Stems 9-30 dm. 

 tall, sometimes smooth and glabrous below, branched above : leaves alternate, opposite or 

 whorled ; blades lanceolate to oblong- or linear-lanceolate, 5-15 cm. long, acuminate, ser- 

 rate or dentate, or nearly entire : heads showy : involucral bracts lanceolate or elliptic- 

 lanceolate, 8-13 mm. long, acuminate, ciliolate : ray-flowers 9-20 ; ligules yellow, 1.5-2 cm. 

 long: disk yellow, 1-1.5 cm. broad. 



In low grounds, Maine to Ontario and the Northwest Territory, Florida and Louisiana. 



40. Helianthus resinosus Small. Perennial, dull green. Stems 8-15 dm. tall, 

 branching above, rigidly hispidulous : leaves mainly opposite ; blades lanceolate to oblong- 

 lanceolate, 5-12 cm. long, acute or somewhat acuminate, entire or undulate, very scabrous 

 above, rough pubescent beneath and with numerous minute resinous glands : heads showy : 

 involucral bracts lanceolate or oblong-lanceolate, acute or slightly acuminate, scabrous- 

 pubescent and glandular like the lower surfaces of the leaves, hispid-ciliate : ray-flowers 9- 

 15 ; ligules bright yellow, about 2.5 cm. long : disk becoming 2 cm. broad. 



In swamps and meadows, near River Junction, Florida. Summer. 



