1312 CICHORIACEAE 



drooping, rather few in each cluster : invohicres glabrous, purplish or pale green ; larger 

 bracts of the outer involucre ovate or triangular-ovate ; inner bracts glabrous, about as long 

 as the pappus : corollas pale yellow or whitish : achenes 4-6 mm. long : pappus light brown. 

 In woods and thickets, Maine to Pennsylvania and North Carolina. Summer and fall. 



7. Nabalus cylindricus Small. Perennial, deep green. Stems 3-9 dm. tall, nearly 



simple, glabrous, finely ridged, each topped with a narrowly cylindric panicle : leaf- 

 blades triangular or ovate-triangular in outline, 5-10 cm. long, acute or acuminate, 3-lobed 

 or 3-cleft and sinuate or angularly toothed, truncate or cordate at the base, lower ones on 

 long slender petioles, the upper shorter-petioled : heads in axillary clusters, thus form- 

 ing a narrowly cylindric panicle : involucres narrow, about 10-11 cm. high ; inner bracts 

 linear or linear-lanceolate, with few scattered hairs, slightly shorter than the pappus : 

 achenes 5-6 mm. long, glabrous. 



On mountain slopes, Kentucky to North Carolina and Tennessee. Fall. 



8. Nabalus virgatus (Michx. ) DC. Perennial, glabrous, glaucescent. Stems 6-12 

 dm. tall, wand-like : leaf-blades various, those of the basal and lower stem-leaves 1-3 dm. 

 long, sinuate-pinnatifid or pinnately parted ; segments entire or toothed ; blades of the 

 upper leaves gradually smaller and narrower, entire, sessile : panicle narrow and raceme- 

 like, 2-5 dm. long, sometimes much reduced : involucres about 10 mm. high ; inner bracts 

 linear, glabrous : ligules white or pink : achenes about 4 mm. long, brown : pappus straw- 

 colored. \_Prenanthes virgata Michx.] 



In pine lands, New Jersey to Florida. Fall. 



9. Nabalus ^Bper (Michx.) T. & G. Perennial, sometimes scabro-pubescent. Stems 

 erect, 1-2 dm. tall, narrowly branched above : leaf-blades oblong to lanceolate or elliptic, 

 4-20 cm. long, irregularly often sharply toothed, sessile, sometimes slightly clasping : in- 

 volucres 12-14 mm. high : bracts linear or small, outer ones linear-subulate, all more or 

 less distinctly hirsute : ligules cream-colored, often fully 1 cm. long : achenes 5-6 mm. long : 

 pappus sordid brown or pale straw-colored. [Prenanlhes aspera Michx.] 



On dry prairies, Minnesota, south to Kentucky, Kansas and Louisiana. Summer and fall. 



10. Nabalus crepidineus (Michx. ) DC. Perennial, minutely pubescent or gla- 

 brate. Stems 1-2 m. tall, branching above : leaf-blades varying from hastate at the base 

 of stem to ovate-hastate or oblong above, 1-3 dm. long, gradually or abruptly narrowed 

 into winged petioles, coarsely and irregularly dentate: involucres about 12 mm. long; 

 bracts linear, copiously strigose-hirsute on the back, the outer triangular lanceolate to 

 linear-lanceolate : ligules ochroleucous : achenes 4-5 mm. long, 12-15-ribbed, 4 or 5 ribs 

 stronger than the rest : pappus dirty brown. [Prenavthes crepidineus Michx.] 



In rich soil and thickets, Minnesota to Pennsylvania, Tennessee and Kansas. Summer and fall. 



2. HIERACIUM L. 



Perennial, caulescent or scapose herbs, with pubescent, often glandular, or rarely gla- 

 brous foliage. Leaves sometimes all basal : blades simple, entire or toothed. Heads soli- 

 tary, or in corymbs, racemes or panicles, yellow, or orange or red. Involucres various, often 

 double ; inner of narrow bracts in 1-3 series, outer abruptly or gradually smaller. Recep- 

 tacle flat, naked or slightly fimbrillate. Ligules truncate and toothed at the apex. 

 Anthers sagittate at the base. Stigmas slender. Achenes oblong, fusiform or columnar, 

 10-15-ribbed, truncate or narrowed into a neck. Pappus of 1-2 rows of brown or rarely 

 white bristles. Havi'kweed. 



Stems regularly leafy to the broad, more or less effuse panicle : leaf-blades not of a spatulate type. 

 Bladei of tlie lower leaves narrowed at the base : involucres 4-5,5 mm. high : achenes columnar, 2 

 mm. long. 1. H. paniculatum. 



Blades of the lower leaves subcoidate at the base : involucres 7-9 mm. high : 



achenes fusiform, 3 mm. long. 2. H. Floridanum. 



Stems more or less scape-like, corymbose or narrowly cylindric-campanulate 

 above: leaves mainly basal, or on the lower part of the stem, some of the 

 lower blades of a spatulate type. 

 A. Achenes columnar. 



Longer involucral bracts glabrous or nearly so. 



Pappus shorter than the involucre. 3. H. Scribneri. 



Pappus surpassing the involucre. 



Stems nearly naked, glabrous : peduncles glabrous or sparingly glan- 

 dular-pubescent. 4. H. venosum. 

 Stems leafy and pubescent at least below : peduncles densely glan- 

 dular pubescent. 5. H. Marianum. 

 Longer involucral bracts copiously pubescent. 



Pappus shorter than the involucre. 3. H. Scribneri. 



Pappus longer than the involucre. 



a. Stems scape-like, glabrous to the inflorescence. 6. H. Greenii. 



