ORDER LXYIII. COMPOSITE. 405 



bristly. Florets of the ray pistillate, funnel-shaped, irregular ; 

 those of the disk staminate. Pappus consisting of three series, 

 the exterior a toothed margin, the middle one composed of 10 

 or 12 awns, the interior one short, hairy. 



1. C. America'na, (Nutt.) Stem erect, striate, somewhat branched. 

 Leaves glabrous, sessile, oblong-ovate, repand toothed, the upper lance- 

 olate ; scales of the involucre with pectinate appendages. Heads large, 

 ehowy. — Pale purple. Cultivated. Louisiana, Texas. 2 — 3 feet. 



Genus LXXX.— CNI'CUS. VaiU. 

 (From knizo, to prick.) 



Heads many-flowered ; florets of the disk and ray similar. 

 Scales of the involucre coriaceous, produced into long, hard, 

 spiny, pinnate appendages. Mecej^tacle flat, covered with capil- 

 lary bristles. Achenia longitudinally striate. Pappus triple. 



1. C. benedic'tus. Stem villous, branching. Leaves subpinnatifid, 

 clasping, decurrent. Flowers yellow. — 0. Louisiana. 



Genus LXXXL— CIR'SIUM. Tourn. {Cnicus.) 

 (From kirsos, a swelled vein, for which the thistle was supposed to be a remedy.) 



Involucre ventricose, imbricate, with spinose scales. Florets 

 perfect. Receptacle hairy. Pappus plumose, or pilose. 



L C. disco'lor, (Spren.) Stem erect, hairj'. Leaves sessile, pinnati- 

 fid ; segments 2-lobed, spinous, hairy on the upper surface, touientose 

 beneath. Flowers solitary, terminal, on leafy branches; scales of the 

 involucre ovate, terminated by a long spine. Seed smooth ; pappus 

 plumose. — Purple. If. June-— July. Upper dist. Car. and Geo. 



2. C. ALTis'siMUM, (Spren.) Stem erect, branching. Leaves sessile, 

 oblong-lanceolate, scabrous, tomontose beneath, dtnlate, ciliate, radical 

 ones pinnatifid. Floicers tcrminixl ; involucre cylindrical, ovate ; scales 

 ovate, spinous, appressed, pale ; receptacle villous. — Purple. U- July 

 — Sept. Upper dist. Car. and Geo. 2— 3 feet. 



3. C. Virginia'num, (Mich.) Stem simple, angled, tomentosc toward 

 the summit. Leaves sessile, narrow-lanceolate, with spiny teeth, acute, 

 slightly hairy on the upper surface, touientose beneath. Floicers foV\- 

 tary, terminal ; involucre ventricose ; scales nppre.-sed, carinate, ovate. 

 Seeds slightly angled, oblong; pajipus plumose; receptacle bristly. — 

 Purple. If. June — Sept. Pine-barrens. Common. 2 — 3 feet. 



4. C. mu'ticum, (Mich.) Ston erect, slender, branching. L^ravrs pin- 

 natitid, woolly, tomentose beneath; segments with spines, somewhat 

 bracteolate, occasionall}' 3-lobed, pale, acute; branches naked, 1 Adw- 

 ered ; involucre globose; scales without spines, laiuiginous. — Purple. 

 It July — Sept. Mountains. 2 — 6 feet. Ciiicus 7nuticus, Pur.-h. 



5. C. gla'ber. {C. muiicum, Mich.) >S^'m erect, furrowed, .'sprinkled 

 with hair.<, branching. Leaver, sessile, pinnatitid,very long, hairy along the 

 veins, spiny along the margins and angles ; segments 3 — 5-lobed. Flow- 

 ers in panicles. Peduncles slender, elightlv hairy ; seulos of the involu 



