1268 CARDUACEAE 



below the junction of the 3 ribs, entire : involucres less than 1 cm. broad ; bracts nearly 

 subulate to linear-lanceolate, ecilate, lax : disk fully 1 cm. broad : ray-flowers 9-15 ; 

 ligules bright yellow, 1.5-2.5 cm. long : disk about 1 cm. broad. 

 In rocky glades, Alabama. 



25. Helianthus ixiicroc6phalus T. & G. Perennial, bright green. Stems 4-18 dm. 

 tall, smooth and glabrous : leaves opposite ; blades membranous, lanceolate to oblong- 

 lanceolate, 8-18 cm. long, acuminate, remotely serrate or nearly entire, slender-petioled : 

 involucres campanulate, 6-7 mm. high ; bracts linear-lanceolate, lanceolate to oblong, 

 ciliate, the inner acute : ray-flowers 5-10 ; ligules yellow, 1-1.5 cm. long : disk 7-9 cm. 

 broad : achenes cuneate or oblong-cuneate, 4 mm. long, with 2 lanceolate teeth. 



On hillsides or river banks, Pennsylvania to Missouri, Georgia and Louisiana. 



26. Helianthus glaucus Small. Perennial, deep green. Stems 9-18 dm. tall, widely 

 branched, smooth, glabrous, glaucous : leaves opposite ; blades thick, or somewhat leathery, 

 lanceolate, acuminate, sharply serrate, very scabrous above, tomentulose beneath, short- 

 petioled : involucres campanulate, 8-10 mm. high ; bracts few, lanceolate to oblong-lanceo- 

 late, the inner acuminate, white-ciliate, more or less spreading : ray-flowers 5-7 ; ligules 

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



In dry sandy soil, North Carolina to Florida and Alabama. 



27. Helianthus verticillatus Small. Perennial, deep green. Stems 9-18 dm. tall, 

 branching above, smooth and glabrous almost to the heads : leaves in whorls of 3 ; blades 

 Arm, broadly linear or linear-lanceolate, 8-12 cm. long, somewhat acuminate, entire, revo- 

 lute, shagreen-like above, sparsely pubescent beneath, nearly sessile: peduncles strigillose- 

 hispidulous under the heads : involucres turbinate-campanulate, about 10 mm. high ; bracts 

 linear-lanceolate, ciliolate, somewhat spreading : ray-flowers several ; ligules deep yellow, 

 about 2 cm. long : disk about 1.5 cm. broad : achenes about 5 mm. long. 



In wet sandy soil, western Tennessee. Summer. , 



28. Helianthus grosse-serr^tus Martens. Perennial, bright green. Stems 9-30 dm. 

 tall, smooth and glabrous below the inflorescence and often glaucous, branching above : 

 leaves alternate or sometimes opposite ; blades leathery, lanceolate or oblong-lanceolate, 

 1-3 dm. long, acuminate, serrate, sometimes saliently so, short-petioled above the base of 

 the stem : involucre-body about 1.5 cm. broad ; bracts linear-lanceolate to lanceolate, or 

 oblong to cuneate with a lanceolate tip, 1-2 cm. long : ray-flowers numerous ; ligules 2.5-4 

 cm. long : disk 1.5-2 cm. wide. 



On dry plains and prairies, Long Island and Pennsylvania to South Dakota and Texas. 



29. Helianthus decap6talus L. Perennial, deep green. Stems5-16 dm. tall, smooth 

 and glabrous below the inflorescence : leaves opposite ; blades membranous, ovate to ob- 

 long-lanceolate, 8-20 cm. long, acuminate, coarsely serrate, cuneate or truncate at the 

 base, somewhat scabrous on the upper surface : heads conspicuous : involucral bracts linear 

 to linear-lanceolate, 1.5-2 cm. long, ciliate: disk becoming about 1.5 cm. broad: ray- 

 flowers several ; ligules bright yellow, oblong to linear-oblong, 2.5-3 cm. long. 



In thickets and on banks, Quebec to Michigan, Georgia and Kentucky. Summer. 



30. Helianthus saxlcola Small. Perennial, glabrous or nearly so to the inflores- 

 cence. Stems sometimes tufted, 8-15 dm. tall, simple or rarely sparingly branched near 

 the top : leaves opposite below, alternate above ; blades ovate-lanceolate to lanceolate, 

 acuminate, shallowly serrate, deep green and quite smooth above, whitish green and 

 essentially glabrous beneath : heads solitary or few, showy : peduncles sparingly pubes- 

 cent : involucral bracts linear-lanceolate, attenuate, ciliate, more or less recurved : disk 

 yellowish, about 1.5 cm. broad : ray-flowers often 8-10 ; ligules light yellow, 2-3 cm. long. 



On exposed mountain summits. North Carolina and Georgia. Summer. 



31. Helianthus austr^lis Small. Perennial, deep green. Stems 6-15 dm. tall, 

 smooth and glabrous to the inflorescence or near it, branched above : leaves mainly alter- 

 nate ; blades lanceolate, often narrowly so, 10-15 cm. long, or shorter on the upper part 

 of the stem, acuminate, shallowly toothed, very scabrous above, paler beneath and pubes- 

 cent at least along the nerves, short-petioled : peduncles scabrous-pubescent : involucral 

 bracts lanceolate to broadly lanceolate, acuminate, ciliate, otherwise glabrous or nearly so, 

 the inner dilated alwut the middle : disk yellowish, about 1.5 cm. broad : ray-flowers 

 10-15; ligules bright yellow, 1.5-2 cm. long. 



In stony or sandy soil, Georgia to Florida and Louisiana. 



32. Helianthus strumosus L. Perennial, bright green. Stems 6-18 dm. tall, smooth 

 and glabrous, or nearly so, to the inflorescence, often glaucous : leaves opposite ; blades 

 thinnish, ovate to lanceolate or oblong-lanceolate, 8-20 cm. long, acuminate, entire or ser- 

 rate, whitish beneath and sometimes tomentulose : heads showy : involucral bracts lanceo- 



