238 COMPOSITE. (COMPOSITE FAMILY.) 



* Involucre smooth or nearly so, 5 - \Z-flowered. 



1. N. &lbus, Hook. (WuiTE LETTUCE. RATTLESNAKE-ROOT.) 



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

 leaves angulate or triangular-halberd-form, sinuate-toothed, 01 3-5-cleft; the 

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

 jhicered; pappus deep cinnamon-color. Var. SERPENTARIA is a form with deep- 

 ly divided leaves, their margins often rough-ciliate. 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. IV. 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 kafy panicle ; leaves mem branaceous, 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. Rich moist woods ; common, especially northward. 

 Aug., Sept. 



3. N. Fraseri, DC. (LION'S-FOOT. GALL-OF-THE-EARTH.) Nearly 

 smooth ; stem corymbose-panic/ed at the summit (l-4 high) ; leaves mostly del- 

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

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

 plish, sometimes slightly bristly) of about 8 scales, 8 - 12-Jiowcred ; pappus dull 

 straw-color. Varies greatly in foliage: the var. rNTEGRir6Lius has the thick- 

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

 England to Virginia and southward. Sept. 



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

 heads in axillary clusters forming a narrow racemed panicle ; leaves triangular- 

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

 (livid) \Q-l3-jlowercd, of about 8 proper scales and several very short bract-like ones, 

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

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

 York. Aug. - Oct. 



5. N. Boottii, DC. Stem simple, dwarf (5' -6' 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- \8-Jlowered, of 10- 15 very obtuse 

 proper scales, and several linear and loose exterior 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. N. virgiitus, DC. (SLENDER RATTLESNAKE-ROOT.) Smootn, 

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

 and slender spiked raceme (H-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- \2-flowered; 

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

 ward Sept. 



