238 coMPOsiTiE. (composite family.) 



* Involucre smooth or neariy so, 5 - \2-flowered. 



1. IV. Slbus, Hook. (White Lettuce. Rattlesnake-koot.) 

 Smooth and glaucous (2° -4° high) ; stem corymbose-panicled at the summit: 

 leaves angulate or triangular-halberd-form, sinuate-toothed, or 3-5-cleft; the 

 uppermost oblong and undivided; involucre (purplish) of about 8 scales, 8-12- 

 Jiowcred: pappus deep cinnmnon-color. — Var. SEKPENTiEiA is a form with deep- 

 ly divided leaves, their margins often rough-eiliate. — Borders of woods, in rich 

 soil ; common, especially northward. Aug. — Stouter and more corymbed than 

 the next, with thickish leaves and often purplish branches. Heads ^' long. 



2. N. altissimus, Hook. (Tall White Lettuce.) Smooth; stem 

 tall and slender (3° - 6° high) ; the heads in small axillary and terminal loose 

 clusters forming a long and wand-like leafy panicle ; leaves membranaceous, all 

 petioled, ovate, heart-shaped or triangular, and merely toothed or cleft, with 

 naked or winged petioles, or frequently 3 - 5-parted, with the divisions entire or 

 again cleft; involucre slender (greenish), of 5 scales, 5 -(> flowered; pappus dirty 

 white, or pale straw-color. — Kich moist woods ; common, especially northward. 

 Aug., Sept. 



3. ]V. Fraseri, DC. (Lion's-foot. 6all-of-tiie-eakth.) Nearly 

 smooth ; stem corymbose-panicled at the summit (1° -4° high) ; leaves mostly del- 

 toid, roughish ; the lower variously 3 - 7-lobed, on margined petioles ; the upper 

 oblong-lanceolate, mostly undivided, nearly sessile ; involticre (greenish or pur- 

 plish, sometimes slightly bristly) of about 8 scales, &-\2-flowered ; pappus dull 

 slraw-color. — Varies greatly in foliage : the var. iNTEGKirbLius has the thick- 

 ish leaves all undivided and merely toothed. — Dry sandy or sterile soil, S. New 

 England to Virginia and southwai-d. Sept. 



4. N. lisinus, DC. Smooth; stem low and simple (5' -10' high); the 

 heads in axillary clusters forming a naiTOw raceraed panicle ; leaves triangular- 

 halberd-shaped and very variously lobed or cleft, on slender petioles ; involucre 

 (livid) 10 - 13-Jioiaeredj of about 8 proper scales and several very short brad-like ones, 

 which are triangular-ovate and appressed ; pappus dark straw-color. — Alpine 

 summits of the White Mountains of New Hampshire, and Mount Marcy, New 

 York. Aug. - Oct. 



5. N. Bodttij, DC. Stem simple, dwarf {b'-d' high), pubescent at the 

 summit ; the heads in an almost simple raceme ; lowest leaves halberd-shaped 

 or heart-shaped, the middle oblong, the upper lanceolate, nearly entire, tapering 

 into a margined petiole; involucre (livid) 10- 18^!«e7-ed, o/' 10 - 15 very oUust 

 proper scales, and several linear and loose exteiior ones nearly half the length of the 

 former ; pappus straw-color. — Higher alpine summits of the mountains of 

 Maine, New Hampshire, and N. New York. Aug. 



6. Bf. virg^atus, DC. (Slender Rattlesnake-eoot.) Smooth, 

 slightly glaucous ; stem very simple (2° -4° high); produced above into a naJced 

 and slender spiked raceme (lj° -2° long), the heads clustered and mostly unilat- 

 eral; leaves lanceolate, acute, closely sessile, the upper reduced to bracts, the 

 lower toothed or pinnatifid ; involucre (purplish) of about 8 scales, 8 - 12-fowered ; 

 pappus straw-color. — Sandy pine barrens, New Jersey to Virginia, and south- 

 ward. Sept. 



