1266 CAKDUACEAE 



each sessile by a slightly dilated base: bracts of the involucre filiform-subulate, 1.5-2 cm. 

 long, loosely spreading, "scarcely ciliolate and somewhat granular, attenuate into very slen- 

 der tips which greatly surpass the disk in length : disk about 1 cm. broad ; ligules of the 

 ray-flowers 1-2 cm. long. 



On limestone bluffs and in limestone soil, Texas. Fall. 



9. Helianthus orgyalis DC. Perennial, smooth and glabrous. Stems 1-3 m. tall, 

 glaucous, branching above : leaves numerous, alternate ; blades narrowly linear, 10-40 cm. 

 long, attenuate, entire or serrulate, short-petioled or nearly sessile : bracts of the involucre 

 1-1.5 cm. long, linear or linear-lanceolate, ciliate, attenuate into filiform tips, which 

 slightly surpass the disks in length ; ligules of the ray-flower 2-2.5 cm. long : disk 1-1.5 

 cm. broad. 



On plains, Nebraska to Colorado, Arkansas and Texas. 



10. Helianthus polyphyllus Small. Perennial, deep green. Stems 9-20 dm. tall, 

 branching above, densely hirsute near the base, glabrous and often smooth above : leaves 

 numerous ; blades narrowly linear, 5-16 cm. long, entire, strongly re volute and apparently 

 thick, filiform, curved : bracts of the involucres linear-subulate, attenuate into subulate 

 tips, about 1 cm. long, some drooping or recurving : ray -flowers few ; ligules 1.5-2 cm. 

 readily shrivelling : disks 1-1.5 cm. broad, depressed. 



In thickets, Georgia and Arkansas. Fall. 



11. Helianthus angustifolius L,. Perennial, scabrous or hispidulous. Stems 6-18 

 dm. tall, more or less branched : leaves few, alternate ; blades linear or narrowly linear on the 

 lower part of the stem, entire, somewhat revolute, 8-20 cm. long, sessile, or the lower one 

 on winged petiole : bracts of the involucre linear-lanceolate to linear-subulate, attenuate 

 into slender tips, 8-12 mm. long, minutely pubescent or hispidulous : ray -flowers several ; 

 ligules about 2 cm. long, not readily shrivelling : disks 1-1.5 cm. broad. 



In moist soil or swamps, New York and Missouri to Florida and Texas. Late summer and fall. 



12. Helianthus elongatus Small. Perennial, tufted. Stems 6-12 dm. tall, simple, 

 or branched above : leaves opposite ; blades elliptic-oblong to linear, 5-20 cm. long, en- 

 tire, very scabrous on both sides, the lower ones petioled, the upper sessile : heads showy, 

 solitary or few, long-ped uncled : involucres about 2 cm. broad ; bracts lanceolate, attenuate 

 into slender tips, ciliate, and more or less hispid : ray-flowers 15-25 ; ligules 2-4 cm. long : 

 disks brown-purple. 



In pine lands, Florida to Louisiana. 



13. Helianthus ciliaris DC. Perennial, smooth. Stems 3-7 dm. tall, more or 

 less branched : leaves mostly opposite ; blades linear or linear-lanceolate, acute, undu- 

 late, repand or bristly on the margins : heads not showy : involucres 1.5-2 cm. broad ; bracts 

 Dvate to lanceolate, 5-7 mm. long, obtuse, acute or mucronate, pectinately hispid -ciliate : 

 ray-flowers 14-19 ; ligules 1-1.5 cm. long or smaller, or obsolete : disk brownish, 1-2 cm. 

 broad. 



In low or brackish soil, Texas to Arizona and adjacent Mexico. 



14. Helianthus undulatus Chapm. Perennial, scabrous. Stems 6-18 dm. tall, simple 

 or branching above : leaves numerous, opposite on the lower part of the stem, alternate 

 above ; blades lanceolate, oblong or linear-lanceolate, 3-10 dm. long, usually abruptly acute, 

 entire or nearly so, slightly revolute, paler beneath and less scabrous than above, short- 

 petioled or nearly sessile : heads showy : involucres 1.5-2 cm. broad ; bracts oblong to lan- 

 ceolate, the inner acuminate, 5-8 mm. long : ligules of the ray-flowers 2-3.5 cm. long : 

 disk becoming brown, 1-1.5 cm. broad. 



In sandy soil, Florida and Alabama. Fall. 



15. Helianthus scabrrimus Ell. Perennial, scabrous. Stems rigid, 5-25 dm. 

 tall, simple or sparingly branched : leaves few, opposite ; blades leathery, those of the 

 lower cauline leaves elliptic to ovate-elliptic, 1-2 dm. long, those of the upper lanceolate 

 or elliptic-lanceolate, all exceedingly scabrous, 3-ribbed, shallowly serrate or serrulate : 

 heads usually few, but conspicuous : involucres 2-2.5 cm. broad ; bracts ovate to lan- 

 ceolate and linear-oblong, the inner acute, over 10 mm. long ; ligules of the ray-flowers 

 2.5-4 cm. long : disk brown-purple, 2-3 cm. broad. 



On prairies, Minnesota to Illinois, Georgia and Texas. 



16. Helianthus carnpsus Small. Perennial, smooth and glabrous, somewhat fleshy. 

 Stems 3-10 dm. tall, sometimes tufted, simple : leaves few, opposite below, alternate above ; 

 blades linear-oblong to linear, acutish, entire, sometimes undulate, the lower ones on 

 stout petioles, the upper sessile : heads long-peduncled, showy, solitary : involucres about 

 2 cm. broad ; bracts fleshy, oblong-lanceolate, slightly acuminate, glabrous : disk yellowish, 

 1.5-2 cm. broad : ray-flowers 12-18 ; ligules 1.5-2 cm. long ; achenes 3-3.5 mm. long. 



On sandy beaches, northeastern Florida. Summer. 



