208 COMPOSITE. 



whitish tomentose below ; leaves lanceolate, oblong, few-toothed, sessile, 

 membranaceous, smooth ; peduncles slender, divaricate ; bracts setaceous. 



Woods. Can. to Geor. W. to Miss. July— Sept. %.—Stem slender, 1—3 

 feet high. Heads small, on long slender peduncles, forming a large panicle. 

 Flowers yellow. Panicled Hawk-weed. 



5. H. Scouleri Hook. : clothed with long brownish rigid and spreading 

 hairs ; stem paniculate, branched ; leaves broad-lanceolate, somewhat co- 

 riaceous, rigid, acute, slightly toothed ; radical attenuated into a short peti- 

 ole ; cauline very remote, sessile ; involucre rusty-pubescent, with long 

 scattered hairs. 



On the Columbia river ; and also gathered in Penn. by Schweinitz. Hooker. 

 Stem a foot high. Heads small. Flowers yellow. Scouler^s Hawk-weed. 



** Stem naked or nearly so. 



6. H. venosum Limi. : stem scape-like, naked or with a single leaf, smooth 

 and branching above ; leaves obovate-oblong and lanceolate, entire or ob- 

 scurely denticulate, hairy on the margin and midrib beneath ; veins pur- 

 ple ; involucre mostly smooth. 



Dry and sandy woods. Can. to Geor. W. to Ken. June — Aug. %. — Stem 

 1 — 2 feet high, naked or with 1 — 2 leaves, branched at the summit. Radical 

 leaves spreading on the ground, colored with dark veins. Heads small, on slen 

 der peduncles, forming a loose panicle. Flowers yellow. This is one of the 

 plants in common repute as an antidote or remedy for the poison of the rattle- 

 snake ; but we are still in want of proof in regard to its medicinal power. 



Veiny Hawk-ioeed. 



. 66. NABALUS. Cass.— Nabalus.> 

 (Origin unknown.) 

 Heads 5 — 30-flowered. Involucre cylindric, of 10 — 14 lin- 

 ear scales, calyculate at base. Receptacle naked. Achenia ob- 

 long, subcylindraceous, sulcate, smooth,' truncate at the apex. 

 Pappus in many series of yellow or brownish rough rigid hairs. 



1. N. Serpentarius Hook. : leaves toothed, rough ; radical palmate ; cau- 

 Une on long petioles, sinuate-pinnatifid, somewhat 3-lobed, the middle seg- 

 ment 3-parted ; upper leaves lanceolate ; racemes terminal, paniculate, 

 short, nodding ; involucre 8-leaved, 12-flowered. N. albus,\a.r. Serpentaria 

 Torr. <f« Gr. Harpalyce Serpentaria Don. Prenanthes Serpentaria Pursh. 



Woods on hill sides. Hudson's Bay to Car. Aug., Sept. %.. — Stem 2 — 5 

 feet high, simple or much branched. Heads in loose terminal panicles. Invo- 

 lucre purplish. Flowers white or yellowish. A very variable species, which 

 may perhaps be more properly united with the next, as has been done by Torrey 

 and Gray, and Dr. Darlington. It has gained some notoriety as a cure for the 

 bite of the rattlesnake, but I apprehend that the statements on this point are en- 

 titled to very little credence. Rattlesnake Root. Lion's Foot. 



2. N. alhus Hook. : smooth and somewhat glaucous ; stem paniculate at 

 the summit ; leaves angular-hastate, irregularly toothed, sinuate-incised or 

 pinnately 3 — 5-parted; the lower petioled, upper sessile; racemes short, 

 paniculate; involucre about 8-leaved, 8 — lO-flowered. Harpalyce alba Don. 

 Prenanthes alba Linn. 



Woods. Can. to Car. Aug. 11-. — Stem 3 — 5 feet high. Heads numerous, 

 in a loose panicle which is composed of small terminal clusters. Flowers white. 

 Achenia yellow. Pappus deep cinnamon-color. White Lettuce. 



