COMPOSITE. 189 



or somewhat quadrangular achenia. Pappus mostly of 2 un- 

 equal chaffy scales or awns, (sometimes additional smaller ones,) 

 deciduous. 



* Disk flowers dark purple. 



1. H. atrorubens Linn.: stem erect, branched above, hispid with long 

 scattered hairs ; leaves mostly opposite, oblong-spatulate or ovate, some- 

 what serrate, 3-nerved, scabrous ; scales of the involucre lanceolate, acu- 

 minate, smooth, as long as the disk. 



Gravelly soils. Perm, to Car. W. to Miss. Aug., Sept. ^.Stem 34 feet 

 high, somewhat branched. Lower leaves very large and often slightly cordate. 

 Heads in a loose terminal panicle ; rays about 16, yellow ; disk dark purple. 



Dark-red Sunflower. 



2. H. angustifolius Linn. : stem scabrous or hairy ; leaves narrow-lan- 

 ceolate, sessile, entire, 1-nerved, rough above, pale beneath, the margins 

 revolute ; lower opposite, upper alternate ; scales of the involucre linear- 

 lanceolate, as long as the disk ; chaff 3-toothed. Rudbeckia angustifolia 

 Linn. 



Swamps in pine barrens. N. J. to Flor. W. to Texas. Aug. Oct. Tj.. 

 Stem 2 -6 feet high, slender, sparingly branched. Heads small, somewhat co- 

 rymbose, on slender peduncles ; rays 12 20, yellow ; disk dark purple. 



Narrow-leaved Sunflower. 



** Disk flowers yellow. 

 \ Leaves opposite, or the upper sometimes alternate. 



3. H. mollis Lam. : stem villous ; leaves ovate or lanceolate, acuminate, 

 somewhat clasping at base, entire or serrulate, scabrous above, tomentose 

 canescent beneath ; scales of the involucre lanceolate, villous -canescent. 

 //. canescens Mick. 



Low grounds. Penn. ? and Ohio to Geor. W. to Texas. July Sept. Tj.. 

 Stem 24 feet high, simple or sparingly branched. Heads few, rather large ; 

 rays 15 25, about an inch long. Woolly Sunflower. 



4. H. strumosus Linn. : stem rough above, smooth below ; leaves ovate- 

 lanceolate, with a long tapering point, serrate, 3-nerved, rough above, 

 whitish and pubescent beneath, abruptly tapering into a short winged pe- 

 tiole ; scales of the involucre lanceolate, acuminate, equalling the disk. 

 H. macrophyttus Willd. 



Dry woods. Can. to Geor. W. to Ark. Aug., Sept. ^.Steni 2 4 feet 

 high, slender, simple or sparingly branched. Heads few, on roughly pubescent 

 peduncles ; rays about 10, bright yellow. Sharp-leaved Sunflower. 



5. H. divaricatus Linn. : stem smooth, simple or dichotomously branched 

 above; leaves sessile, ovate-lanceolate, rounded at base, tapering to the 

 point, serrate, 3-nerved, scabrous above, rough-pubescent beneath ; scales 

 of the involucre lanceolate, acuminate, ciliate, spreading. 



Woods. Can. to Flor. Aug. Oct. 'Zj.. Stem I 5 feet high, sometimes 

 purple and glaucous. Heads small, few, in a terminal panicle ; rays 8 12, bright 

 yellow ; disk yellow. Rough-leaved Sunflower. 



6. H. decapetalus Linn. : stem erect, smooth below, rough above ; leaves 

 ovate or oblong-ovate, on short winged petioles, acuminate, coarsely serrate, 

 3-nerved, thin and slightly scabrous ; scales of the involucre linear-lanceo- 



