CICHO RIA CEA E. 907 



2. Nabalus albus (L.) Hook. RATTLESNAKE-ROOT. WHITE LETTUCE. 

 (I. F. f. 3577.) Glabrous and glaucous; stem commonly purple, 6-15 dm. high. 

 Leaves hastate, ovate, cordate, denticulate, dentate, lobed, or palmately divided, 

 or the upper lanceolate, entire; heads numerous, pendulous, about 6 mm. broad, 

 paniculate, or thyrsoid. and often in axillary clusters; involucre glabrous, or with 

 a few scattered hairs, glaucous, 10-14 mm. high, its principal bracts about 8, 

 purplish; flowers greenish or yellowish white, fragrant. In woods, Me. and Out. 

 to Manitoba, south to Ga. and Ky. Aug. -Sept. [Prenanthes alba L.] 



~. Nabalus serpentarius (Pursh) Hook. LION'S-FOOT. GALL-OF-THE-EARTH, 

 (I. F. f. 3578.) Glabrous or sparingly pubescent, green; stem stout or slender, 

 not glaucous, 3-12 dm. high. Leaves rather firm, similar to those of the preced- 

 ing species, equally variable in outline, often pinnatifid or pinnately lobed, or 

 p.\lmately divided; inflorescence paniculate, the branches divaricate, upcurved; 

 heads numerous, about 6 mm. broad, pendulous; involucre more or lebs bristly- 

 hispid, rarely glabrous, 10-14 mm. long, its principal bracts about 8, shorter than 

 die pappus; flowers whitish or cream-color, rarely yellow. In fields and thickets, 

 Ont. to southern N. Y., Fla., Ala. and Ky. July- Oct. 



Nabalus serpent&rius integrifblius (Cass.) Britton. Leaves oblong to oval, irregu- 

 larly dentate, denticulate or entire. L. I. to N. Car. 



4. Nabalus trifoliolatus Cass. TALL RATTLESNAKE- ROOT. (I. F. f. 3579.) 

 Glabrous throughout; stem usually stout, 10-27 dm. high. Leaves thinnish, the 

 lower long-petioled, usually 3-divided with the divisions stalked or sessile, the 

 upper short petioled or sessile, all commonly lobed or dentate, but the upper some- 

 times lanceolate, acuminate and entire; panicle-branches ascending, or nearly 

 erect; heads few in the clusters, drooping; involucre glabrous, 12 mm. long, its 

 principal bracts 6-8, equalling the pappus; flowers whitish or pale yellow. In 

 woods and thickets, Me. to Vt., Penn., Tenn. and Mo. Aug. -Oct. 



5. Nabalus nanus (Bigel.) DC. Low RATTLESNAKE-ROOT, or LION'S-FOOT. 

 (I. F. f. 3580.) Glabrous throughout; stem simple, erect, 1-4 dm. high. Basal 

 and lower leaves slender petioled, 3-divided, or sometimes broadly hastate, the 

 divisions variously lobed, toothed, or entire; upper leaves much smaller, entire, 

 toothed, or lobed, sessile, or short-petioled; inflorescence rarely with I or 2 short 

 ascending branches; involucre dark purple-brown or nearly black, glabrous, 

 8-12 mm. long, its inner bracts 6-8, slightly ciliate at the apex, about as long as 

 the pappus. Alpine summits of the Adirondacks and the mountains of N. Eng. ; 

 N. S. to Lab. and Newf. Aug. -Sept. 



6. Nabalus virgatus (Michx.) DC. SLENDER RATTLESNAKE-ROOT. DE 

 WITT'S SNAKEROOT. (I. F. f. 3581.) Glabrous, somewhat glaucous; stem strict, 

 mostly simple, 6-12 dm. high. Leaves lanceolate or oblong-lanceolate, the basal 

 and lower ones sinuate-pinnatifid or pinnately parted, petioled, often 25 cm. 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 4 mm. broad, in a narrow, simple or branched, terminal thyrsus, often uni- 

 lateral; involucre 10 mm. long, its principal bracts about 8; flowers white, or pink- 

 ish. In moist sandy soil, N. J. to Fla., near the coast. Sept-Oct. 



7. Nabalus Boottii DC. BOOTT'S RATTLESNAKE-ROOT. (I. F. f. 3582.) 

 Glabrous below, commonly pubescent above; stem simple, 1-3.5 dm. high. 

 Leaves thickish, the basal and lower ones ovate, hastate, or deltoid, petioled, 

 mostly obtuse, entire, or denticulate, 3-5 cm. long, the upper ovate or oblong, 

 usually entire, short-petioled or sessile, much smaller; heads erect, spreading, or 

 some of them pendulous, racemose or somewhat thyrsoid, 8-10 mm. broad; invo- 

 lucre campanulate-oblong, 8-14 mm. long, dark purplish green, its principal bracts 

 8-10, obtuse or obtusish; flowers whitish, odorous. Alpine summits of the moun- 

 tains of northern N. Eng. and N. Y. July-Aug. 



8. Nabalus asper (Michx.) T. & G. ROUGH WHITE-LETTUCE. (I. F. f. 3583. ) 

 Stem virgate, 6-12 dm. high. Leaves firm, oval, oblong, or oblanceolate, those of 

 the stem all closely sessile, acute or acutish, dentate, denticulate, or the upper- 

 most entire, the lower sometimes clasping, 5-7 cm. long, 1-2.5 cm - wide, the basal 

 tapering into winged petioles, commonly obtuse; heads numerous, erect, spread- 

 ing, or slightly drooping, 6-8 mm. broad, i2-i6-flowered, in a long narrow thyrsus; 



