COMPOSITE. (COMPOSITE FAMILY.) 237 



* * Heads small : involucre cylindrical, scarcely imbricated. 



2. II. SCfalM'UBSll, Michx. (IlouGH HAWKWEED.) Stem rather stout 

 (l-3high), leafy, ronnh-hairy ; tlic stiff flexuous panicle at iirst racemose, 

 at length rather corymbose; the thickish pednnclts and the hoary 40- 50-llow- 

 ereil involucre densely clothed with dark glandular bristles; achenia columnar, not 

 tapering at. the summit; leaves obovate or oval, nearly entire, hairy. Dry open 

 woods ; common, especially northward. Aug. 



3. II. foiagipiluni, Torr. (LOXG-BEARDED HAWKWEED.) Stem wand- 

 like, simple, stout (2 -3 high), very leafy towards the base, naked above, and 

 bearing a small racemed panicle ; the lower portion and both sides of the ob- 

 long-lanceolate or spatulate entire leaves tliickly clothed with very long and upright 

 britflis ; peduncles with the 20 - 30-flowered involucre glandular-bristly; achenia 

 tpindie-shaped, narrowed at the apex. Prairies, Michigan to Illinois, and west- 

 ward. Aug. Heads intermediate between the last and the next. Bristles 

 straight and even, as if combed, often 1' long ! 



4. II. Gl'Ollovii, L. (HAIRY HAWKWEED.) Stem wand-like, mostly 

 simple, leafy and very hairy below, naked above and forming a long and narrow 

 panicle; leaves oblong or obovate, nearly entire, hairy ; the slender peduncles 

 and the 20 - 30-fiowercd involucre sparingly glandular-bristly; achenia spindle- 

 shaj)ed, with a very taper summit. Dry sterile soil ; common, especially south- 

 ward. Aug. Varies from 1- 4 high; with small heads and almost beaked 

 fruit, which well distinguishes the largest forms from No. 2, and the smallest 

 naked-stemmed states from the next. 



5. II. veilOSUin, L. (RATTLESNAKE-WEED.) Stem or scape naked or 

 with a single leaf, smooth and slender, forking above into a spreading loose corymb ; 

 root-leaves obovate or oblong, nearly entire, scarcely petioled, thin and pale, 

 purplish and glaucous underneath (often hairy along the midrib), marked with 

 purple veins ; peduncles very slender ; involucre 20-flowered ; achenia linear, not 

 tapering above. Var. SUBCAULESCENS has the .stem nioi-e or less leafy next 

 the base. Dry plains and pine woods ; common. Plant 1 - 2 high. 



6. II. pan EC IB la turn, L. (PANICLED HAWKWEED.) Stem slender, 

 leafy, diffusely branched, hairy below (2 -3 high); leaves lanceolate, acute at 

 both ends, slightly toothed, smooth ; heads (very small) in a loose panicle, on slen- 

 der diverging peduncles, 12 - 2Q-floicered / achenia short, not tapering at the sum- 

 mit. Open woods ; rather common. 



7*7. NABAILTJS, Cass. KATTLESNAKE-ROOT. 



Heads few -many-flowered. Involucre cylindrical, of 5 to 14 linear scales in 

 a single row, and a few small bractlets at the base. Achenia linear-oblong, stri- 

 ate or grooved, not contracted at the apex. Pappus of copious stra \v-color or 

 brownish roughish capillary bristles. Perennial herbs, with upright leafy steins 

 arising from spindle-shaped (extremely bitter) tubers, very variable leaves, and 

 raccmosc-panicled mostly nodding heads. Flowers greenish-white or cream- 

 color, often tinged with purple. (Name probably from i/o/3Aa, a liarp, in allu- 

 sion to the lyrate leaves which these plants sometimes present.) Species of 

 Prenanthes, L. See Addend. 



