Genus 66. 



THISTLE FAMILY. 



483 



15. Helianthus grosse-serratus Martens. 

 Saw-tooth Sunflower. Fig. 4475. 



Helianthus grosse-serratus Martens, Sel. Sem. Hort. 

 Loven. 1839. 



Perennial by fleshy roots and slender rootstocks; 

 stems glabrous, glaucous, branched above, 6-io 

 high, the branches usually strigose-pubescent. Leaves 

 long-lanceolate, slender-petioled, the upper alternate, 

 the lower opposite, long-acuminate, narrowed at the 

 base, sharply serrate, or merely denticulate, the up- 

 permost entire, rough above, densely puberulent or 

 canescent beneath, 4'S' long, i'-i' wide; heads sev- 

 eral or numerous, 1F-3' broad; involucre hemi- 

 spheric, its bracts squarrose, narrowly lanceolate, 

 acuminate, hirsute; chaff linear-oblong, pubescent at 

 the summit, acute, often 3-toothed ; disk yellowish ; 

 rays 10-20, deep yellow ; achenes nearly glabrous ; 

 pappus of 2 lanceolate awns. 



In dry soil, Maine to Long Island, Pennsylvania, On- 

 tario, Soutli Dakota, Missouri, Kansas and Texas. Aug.- 

 Oct. 



16. Helianthus Kellermani Britton 

 Kellerman's Sunflower. Fig. 4476. 



Helianthus Kellermani Britton, Manual 994. 1901. 



Stem 6-io high, very smooth, much branch- 

 ed above, the branches slender. Leaves nar- 

 rowly elongated-lanceolate to linear-lanceolate, 

 drooping, rather thin, distantly serrate with 

 very small teeth, long-acuminate at the apex, 

 attenuate at the base into short petioles or the 

 upper sessile, scabrate and sparingly pubes- 

 cent on both surfaces, pinnately veined, the 

 lower about 8' long and 7" wide; branches of 

 the inflorescence pubescent; bracts of the in- 

 volucre linear-lanceolate, about 7" long, and 1" 

 wide or less at the base, ciliate, long-acumi- 

 nate; rays golden-yellow, I -if long; chaff of 

 the receptacle linear. 



Dry soil, 

 Sept. 



licinity of Columbus, Ohio. Aug 



17. Helianthus divaricatus L. Rough or 

 Woodland Sunflower. Fig. 4477. 



Helianthus divaricatus L. Sp. PI. 906. 1753. 



Perennial by slender rootstocks ; stem glabrous 

 throughout, or pubescent at the summit, slender, 

 2-7 high. Leaves usually all opposite, divaricate, 

 lanceolate or ovate-lanceolate, firm, dentate or den- 

 ticulate, 3-nerved, rough above, pubescent beneath, 

 sessile or nearly so by a truncate base, tapering 

 gradually to the long-acuminate apex, 3'S' long, 

 i'-ij' wide; heads few or solitary, about 2' broad, 

 borne on strigose-pubescent peduncles ; involucre 

 hemispheric, its bracts lanceolate or ovate-lanceo- 

 late, strigose or hirsute, the outer ones spreading; 

 disk yellow; rays 8-15; chaff of the receptacle 

 apiculate; achenes glabrous; pappus of 2 short 

 subulate awns. 



In dry woodlands, Maine and Ontario to Manitoba, 

 Nebraska, Florida and Louisiana. July-Sept. 



