CICHORIACEAE. 



VOL. III. 



In fields and thickets, Massachusetts to southern New York, Florida, Alabama, Kentucky and 

 Mississippi. Canker-weed. Rattlesnake-root. White lettuce. Snake-gentian. July-Oct. 



Nabalus cylindricus Small, of the southern mountains, ranging north to Kentucky, differs by 

 an elongated narrow panicle. 



4. Nabalus trifoliolatus Cass. Tall Rattle- 

 snake-root. Fig. 4113. 



Nabalus trifolilatus Cass. Diet. Sci. Nat. 34: 95. 1825. 

 Prenanthes trifoliata Fernald ; Brainerd, Jones & Eggles- 

 ton, Fl. Verm. 89. 1900. 



Glabrous throughout ; stem usually stout, 3-9 

 high. Leaves thinnish, the lower long-petioled, usu- 

 ally 3-divided with the divisions stalked or sessile, 

 the upper short-petioled or sessile, all commonly 

 lobed or dentate, but the upper sometimes lanceo- 

 late, acuminate and entire ; inflorescence paniculate, 

 the panicle-branches ascending, or nearly erect ; 

 heads few in the clusters, drooping, 7-12-flowered ; 

 involucre pale green or purplish, glabrous, about li" 

 thick and 6" long, its principal bracts 6-8, equalling 

 the pappus, the short outer ones ovate to lanceolate; 

 flowers whitish or pale yellow; achenes 2" -3" long; 

 pappus light brown. 



In woods and thickets, Newfoundland to Pennsylva- 

 nia, Indiana, Delaware and Tennessee. Aug.-Oct. 



5. Nabalus nanus (Bigel.) DC. Low Rattlesnake-root, or Lion's-foot. Fig. 41 14. 



Prenanthes alba var. nana Bigel. Fl. Bost. Ed. 2, 286. 



1824. 



Nabalus nanus DC. Prodr. 7: 241. 1838. 

 Prenanthes nana Torr. ; Robinson & Fernald in A. 



Gray, Man. Ed. 7, 871. 1908. 

 Prenanthes serpentaria var. nana A. Gray, Syn. Fl. 



i : Part 2, 434. 1884. 



Glabrous throughout ; stem simple, erect, 4'-i6' 

 high. Basal and lower leaves slender-petioled, 

 3-divided, or sometimes broadly hastate, the divi- 

 sions variously lobed, toothed, or entire, usually 

 sessile, occasionally stalked ; upper leaves much 

 smaller, entire, toothed, or lobed, sessile, or short- 

 petioled ; inflorescence thyrsoid, glomerate-spicate 

 or racemose, rarely with i or 2 short ascending 

 branches; involucre dark purple-brown or nearly 

 black, glabrous, 4"-6" long, its inner bracts 6-8, 

 slightly ciliate at the apex, about as long as the 

 usually bright brownish pappus; outer bracts lan- 

 ceolate to ovate-lanceolate. 



Alpine summits of the Adirondacks and the moun- 

 tains of New England ; Nova Scotia to Labrador and 

 Newfoundland. Aug.-Sept. 



6. Nabalus virgatus (Michx.) DC. Slender 

 Rattlesnake-root. Fig. 4115. 



Prenanthes virgata Michx. Fl. Bor. Am. 2 : 84. 1803. 

 Nabalus virgatus DC. Prodr. 7: 242. 1838. 



Glabrous, somewhat glaucous ; stem strict, mostly 

 simple, 2-4 high. Leaves lanceolate or oblong- 

 lanceolate, the basal and lower ones sinuate-pin- 

 natifid or pinnately parted, petioled, often 10' long, 

 the lobes entire or dentate, distant ; upper leaves all 

 sessile, pinnately lobed, or the uppermost entire, 

 very small and bract-like ; heads very numerous, 

 pendulous, about 2" broad, in a narrow, simple or 

 branched, terminal thyrsus, often unilateral ; invo- 

 lucre purplish, about i$" thick and 5" long, its 

 principal bracts about 8, with several minute outer 

 ones; flowers white or pinkish; pappus straw-color. 



In moist sandy soil, New Jersey to Florida, near the 

 coast. Called also De Witt's-snakeroot. Sept.-Oct. 



