GENUS 23. CHICORY FAMILY. 337 
7. Nabalus Bodttii DC. Boott’s Rattle- \ 
snake-root. Fig. 4116. 
Nabalus Boottii DC. Prodr. 7: 241. 1838. 
meep antes Boottii A. Gray, Syn, Fl. 1: Part 2, 435. 
1884. 
Glabrous below, commonly pubescent above; 
stem simple, 4-12’ high. Leaves thickish, the 
basal and lower ones ovate, hastate, or deltoid, 
petioled, mostly obtuse, entire, or denticulate, 1’-2’ 
long, the upper ovate or oblong, usually entire, 
short-petioled or sessile, much smaller; heads 
several or numerous, 10-18-flowered, erect, spread- 
ing, or some of them pendulous, racemose or 
somewhat thyrsoid, 4”-5” broad; involucre cam- 
panulate-oblong, 23-3” thick, 4”-7” long, dark 
purplish-green, its principal bracts 8-10, obtuse or 
obtusish, with several shorter outer ones; flowers 
whitish, odorous; pappus brownish. 
Alpine summits of the mountains of northern New 
England and New York. July—Aug. 
8. Nabalus asper (Michx.) T. & G. Rough 
White-lettuce. Fig. 4117. 
Prenanthes aspera Michx. Fl. Bor. Am. 2: 83. 1803. 
Nabalus asper T. & G. Fl. N. A. 2: 483. 1843. 
Scabrous or rough-puberulent; stem virgate, simple, 
2°-4° high. Leaves firm, oval, oblong, or oblanceolate, 
those of the stem all closely sessile, acute or acutish, 
dentate, denticulate, or the uppermost entire, the lower 
sometimes clasping, 2’-3’ long, 3’-1’ wide, the basal 
tapering into winged petioles, commonly obtuse; heads 
very numerous, erect, spreading, or slightly drooping, 
3-4” broad, 12-16-flowered, in a long narrow thyrsus; 
involucre oblong, 2”-23” thick, 5-7” high, very hirsute, 
its principal bracts 8-10, with several short outer ones; 
flowers light yellow; pappus straw-color. 
On dry prairies, Ohio to South Dakota, Nebraska, Ken- 
tucky, Louisiana and Kansas. Rattlesnake-root. Aug.—Sept. 
9. Nabalus racemésus (Michx.) DC. Glaucous White-lettuce. Fig. 4118. 
Prenanthes racemosa Michx. Fl. Bor. Am. 2: 83. 1803. 
Nabalus racemosus DC. Prodr. 7: 242. 1838. 
Nabalus racemosus pinnatifidus Britton; Britt. & Brown, 
Ill. Fl. 3: 291. 1898. 3 
Prenanthes racemosus var. pinnatifida A. Gray, Syn. Fl. 
1: Part 2, 433. 1884. 
Stem virgate, rather stout, glabrous and somewhat 
glaucous; stem striate, 2°-6° high. Leaves thickish, 
glabrous and glaucous, the lower and basal ones oval, 
oblong, oblanceolate, or obovate, dentate, denticulate, 
pinnatifid or pinnately lobed, 4’-8’ long, mostly ob- 
tuse, tapering into long margined petioles; upper 
leaves sessile, smaller and partly clasping, lanceo- 
late to ovate-lanceolate, denticulate, entire, or pin- 
natifid, mostly acute; heads very numerous, erect, 
spreading, or slightly drooping, 12-16-flowered, 2”°-3” 
broad, in a long narrow thyrsus; involucre oblong- 
cylindric, hirsute, 5’-6” long, 14°-23” thick, longer 
than the hirsute peduncle, its principal bracts 8-10, 
with several small outer ones; flowers purplish; 
Pappus straw-color. 
In moist open places, New Brunswick and Quebec to 
Maine, Manitoba, Alberta, southern New York, New 
Jersey, Iowa, Missouri and Colorado. Aug.—Sept. c 
Prenanthes mainénsis A. Gray, from northern Maine and New Brunswick, is probably a hybrid 
between N. racemosus and N. trifoliolatus. 
22 
