1'72 (OMroSIT.K. ((X»MroSlTK ka.milv.) 



Howi'IvmI ; iiiviplucro siiiootli ; aclicnia sliort, nul iiarruwcd upward. — <(|icii 

 wooils alniii^ tlio inimiilaiiis, < Jc(ir;;ia, ami iinrlliwanl. Augti.sl -Sejit. — Stem 

 2° -3° liij^li. reilumlfs lilifunn. 



:>. H. Marianum, \Vill«l. stem k-aiy , 2^ - :i° lii^li ; leaves oblong, hir- 

 sule liciieatli, tlic luwe.st layering iiito llie densely iiirsute petiole, llie njiper 

 distant, sessile ; heads small, ((irvmbuse ; involucre j^landiilar-liispid ; aclieuia 

 slender, cylindrical. — Mountains of tieor^ia, and nortliward. .July. 



92. PRENANTHES, ^'aill. 



Heads .'3- 2()-Howerc(l. Involucre cylindrical. comi)(jsed of 5-14 linear 

 scales, and several sliort exterior ones, lieceptacle naked. Aclieiiia linear- 

 oljliWij^ or cylindrical, furroweil, glabrous, not narrowed ui)ward. Tapjius of 

 uunieroua straw-colored or brownish bristly hairs. — I'erennial herbs, with 

 bitter tuberous roots, entire or variously Inbed lea\es, and nio.stly nodding 

 heads of yellowish wliile or ])urplisli Howers, in slior( racemes or clusters. 



1. P. crepidinea, .Michx. Smootiiish ; .stem tall, corynibo.sely panided; 

 leaves (jblon^-o\ate or somewhat hastate, acute, une(iually toothed, the lowest 

 ou winged petioles ; involucre Itrown, hairy, of 12-14 scales, 20-35-flowered ; 

 pappus liglit brown. — Mountains of North Carolina and 'J'euue.ssee. Sept. 

 — 8teui 5° - 8^ high. Lower leaves 8' - 12' long. Tlowers yellowish white. 



2. P. alba, L. Smooth ; stem paniculate, purplish ; leaves acutish, anj^led, 

 toothed, or variously 3 - 5-lobed or parted; the lowest petioled ; the upper- 

 most nearly sessile; racemes short, spreading; involucre purplish, of about 8 

 scales, 8- 12-Howered ; pappus light brown; flowers wliite or cream-color. — 

 Open woods in the upper districts of Georgia, and northward. Sept. — Stem 

 30 - 4° high. 



3. P. altissima, L. Smooth ; stem simple or sparingly branched above ; 

 leaves thin, ovate or cordate, petioled, acuminate, denticulate, or the lower 

 ones palmately 3-.5-cleft or parted; heads in .small axillary and terminal 

 clusters, forming a long panicle ; involucre sleniler, greenish, of about .5 scales, 

 5 - 6-flowered ; pappus dirty white or straw-colored. — Varies with the wavy- 

 toothed leaves, deltoid; the lowe.st hastate -3-angled or parted. — Woods 

 along the mountains, Georgia, and northward. Sept. — Stem 3° - 5° high. 

 Flowers yellowish, or greenish white. 



4. P. serpentaria, Pursh. Smooth or sliglitly pubescent; stem corym- 

 bosely panicled above; leaves deltoid, mucronate, pinnately 3-7-lo])ed. on 

 winged petioles ; the upper lanceolate, often entire ; clusters small, terminal ; 

 involucre greenish, smooth or hairy, of about 8 scales, 8 - 12flowered ; pappus 

 straw-color. — Varies Avith the lanceolate or oblong leaves mostly sessile, or 

 the uppermost clasping; the 12-1.5-flowered involucre hirsute with long 

 purplish hairs. — Dry .sterile soil, Florida, and northward. Sept. — Stem 1° - 

 4° high. 



5. P. virgata, Michx. Smooth ; stem simple, virgate ; leaves lanceolate, 

 acute, sessile or partly clasping ; the uppermost small, entire ; the lowest 

 deeply pinnatifid, on margined petioles; clusters of heads small, racemose; 

 involucre smooth, purplish, of about 8 scales, 8-12-flowered; pappus straw- 



