CARDUACEAE 



1253 



linear-lanceolate, 3-15 cm. long, acute, entire : heads showy : involucres flattish in age ; 

 bracts narrowly linear-lanceolate to lanceolate-subulate, 6-10 mm. long, serrulate with 

 spine-like teeth : receptacle conic, becoming columnar : ray-flowers 5-8 ; ligules golden 

 yellow to light orange, 1-2 cm. long : achenes obovoid, turgid, 3 mm. long, striate. 

 On granite rocks, Stone Mountain and vicinity, Georgia. Summer and fall. 



2. Gymnolomia tenuifolia (A. Gray) B. & H. Perennial, shrubby. Stems 5-10 

 dm. tall, scabrous-puberulent, much branched : leaves numerous, the lower alternate, the 

 upper opposite ; blades 3-10 cm. long, pinnately or pedately 3-7-parted, the segments nar- 

 rowly linear : peduncles 5-15 cm. long : heads rather showy : involucres nearly hemis- 

 pheric, 4-5 mm. high ; bracts various, the outer with a cuneate or obovate body and a 

 lanceolate tip, the inner oblong to linear : receptacle low-convex : ray-flowers 9-15 ; 

 ligules yellow, 5-7 mm. long, recurving : achenes 3 mm. long. 



In dry soil, Texas and adjacent Mexico. 



88. RUDBECKIA L.i 



Perennial, or rarely annual or biennial, caulescent herbs. Leaves alternate : blades 

 entire, toothed or pinnatifid, either petioled, sessile or clasping. Heads (in our species) 

 radiate, showy, many-flowered. Involucres hemispheric : bracts imbricated in 2 or more 

 series, rarely foliaceous. Eeceptacle convex or conic, chaffy. Eay-flowers neutral : ligules 

 yellow, rarely discolored (in one species crimson). Disk-flowers perfect, fruit-produc- 

 ing with 5-lobed corollas. Stigmas with blunt or subulate pubescent tips. Achenes 

 4-angled, obtuse or truncate. Pappus of 2-4 short teeth, a low coroniform border, or 

 wanting. Cone-flower.. 



A. Stigmas with short, obtuse tips : pappus present, except in No. 7. 

 Chaff of the receptacle acute, mucronate or obtuse. 

 Chaff canescent or pubescent at the apex. 



Leaf-blades, at least those of the lower leaves, deeply lobed or divided. 

 Plants glabrous or glabrate. 

 Plants cinereous-pubescent. 

 Disk greenish yellow. 

 Disk brown-piirple, anise-scented. 

 Leaf-blades entire or merely toothed. 



Disk globose-ovoid, ovoid-conic or hemispheric: plants pubescent: 

 corolla-lobes reflexed after anthesis. Heliopsides. 

 Cauline leaves petioled. 



Heads small, the disks 1 cm. in diameter or less. 

 Heads large, the disks 1-2 cm. in diameter. 

 Stems glabrous or glabrate. 

 Stems hispid or scabrous. 

 Cauline leaves closely sessile or partly clasping. 

 Disk cylindric or conic-eylindric at maturity: plants glabrous: co 

 roila-lobes erect afteranthesis. Laevigatae. 

 Leaves glaucous, the blades oval, broadly ovate or oblong. 

 Leaves lustrous, the blades narrower. 



Leaf-blades ovate-spatulate to lauceoate-oblong. 

 Leaf-blades elongated-lanceolate, attenuate at both ends. 

 Chaff ciliate, denticulate or entire at the apex. 

 Chaff ciliate or fimbriate at the tip. Fulgidae. 

 Basal and lower stem-leaves cordate or truncate. 

 Chaff 1..5-2.5 mm. broad, densely ciliate at the tip. 

 Chaff narrower, sparsely ciliate at the tip. 

 Basal and lower stem-leaves not cordate or truncate. 



Involucral bracts ciliate, glabrous above : leaves large, long-acu- 

 minate. 

 Stems glabrate or glabrous. 

 : Stems strigose. 



Involucral bracts ciliate, pubescent above : leaves small to medium 

 size, acute or short-acuminate. 

 Uppermost leaves cuneiform or oblong-lanceolate. 



Well developed disks over 1 cm. in diameter : ligules rela- 

 tively short. 

 Well developed disks smaller : ligules relatively large. 

 Uppermost leaves conspicuously dilated. 

 Chaff with entire, hyaline or erose-denticulate tips. 



a. Leaf-blades various, but not elongated-linear Speciosae. 



Ligules large and showy, much exceeding the diameter of the disk. 

 Leaf-blades laciniate. or very coarsely dentate. 

 Prevailing leaves of an ovate type". 

 Prevailing leaves narrower. 

 Leaf-blades remotely or shallowly dentate or entire. 

 Plants glabrous or nearly so. 

 Plants densely hirsute. 



Laciniatae. 



1. a. laciniata. 



2. R. heterophylla. 



3. jK. subtomentosa. 



4. R. Heliopsidis. 



5. R. alismaefoUa. 



6. R. grandiflora. 



7. R. mollis. 



8. R. maxiina. 



9. R. nitida. 

 10. R. glabra. 



11. R. umbrosa. 



12. R. Chapmanii. 



13. R. palusfris. 



14. R. acuminata. 



15. R.fulgida. 



16. R.foliosa. 



17. R. spathulata. 



18. R. Sullivantii. 



19. R. speciosa. 



20. R. truncata. 



21. R. Missoiirifnsie. 



1 Contributed by Mr. C. L. Boynton & Mr. C. D. Beadle. 



