Order TO.— COMPOSITE. 46? 



hairy; pappus in 3 series, the outer 10-toothed, the 2 inner each 



1 O-bristled. — Oriental herbs. 



C. beuedictus L. Lvs. somewhat decurrent; dentate and spiny; invol. doubly 

 spinous, woolly, bracteate. — (D Native of Persia, Tauria and Greece. About 2f 

 high, with yellow flowers. Sparingly naturalized. June. — It was formerly in 

 great estimation in medicine, but is now considered worthless. % § 



95, ONOPOR'DON, Yaill. Cotton Thistle. Heads discoid, homo- 

 gamous ; involucre ventricous, imbricate with spreading, spinous scales ; 

 receptacle deeply alveolate ; pappus copious, capillary, scabrous ; acho- 

 nia 4-angled. — Large, branching herbs, with decurrent leaves. 

 O. acanthium L. Invol. scales spreading, subulate ; lvs. ovate-oblong, decurrent. 

 sinuate, spinous, woolly on both sides. — ;2j This fine looking thistle occurs natur- 

 alized in waste grounds, and is about 3f in height. The whole plant has a white, 

 cottony appearance. Stem winged by the decurrent leaves, which are unusually 

 large. Involucre round, cottony, spinous. Flowers purple. July, Aug. § Eur. 



86. CIR'SIUM, Tourn. (Cnicus L. Muhl.) Thistle. (Gr. Ktpoog, 

 a swelling of a vein, which this plant was supposed to heal.) Heads 

 discoid, horn ogam ous ; involucre subglobous, of many rows of spi- 

 nous-pointed, imbricated scales ; receptacle bristly ; style scarcely 

 divided; pappus copious, plumous ; achenia compressed, smooth. — 

 Herbs with alternate lvs., generally armed with spinous pricMes. Fls. 

 cyanic. 



* Leaves recurrent on the stem more or less. Scales tipped with spines Nos. 1, '2 



* Leaves not decurrent. — Heads involucrate with a whorl of 12 to 20 spiny bracts No. S 



— Heads naked. — Flowers oehroleucous. Scales prickly No. 4 



— Lis. purple. — Lvs. white-tomentous beneath. .Nos. 5 — 7 

 — Lvs. green. — Stem low. simple. .Nos. 8, 'J 

 — Stem tall, branched. .No. 10 

 « 



1 C. lanceolatum Scop. Common' Thistle. Lvs. decurrent, pinnatifid, hispid, 

 the segments divaricate and spinous; hds. several, ovoid, villous ; scales lanceolate, 



' tipped with a spine, spreading. — !§p Common in borders of fields, roadsides, N. 

 Eng. and Mid. States, always distinguished by the decurrent leaves. St. 3 to 4f 

 high, winged by the decurrent leaves which are white and woolly beneath, 

 armed with formidable spines at all points. Fls. numerous, large, purple. InvoL 

 scales, webbed, each ending in a spine. Jl. — Sept. 



2 C. Lecontii Torr. & Gr. Slender, simple, with one head; lvs. linear-lanceolate, 

 more or less decurrent, with a few spinous teeth,' glabrous above, w hite-floccous 

 beneath, invol. ovoid, arachnoid when young; scales r.ot spinous, merely mucro- 

 nate or acuminate-pointed. — Ga. to La. St. about 2f high. Hd. large, (1' or 

 more diam.) terminal. 



3 C. horridulum Mi. Lvs. sessile, pinnatifid, acutely cut, spinous; hds. invested 

 tcith an external invol. of about 12 to 20 very spinous bracts; scales sharp-pointed, 

 but unarmed. — (5) Found in meadows and hills, N. Eng. to Fla. St. 1 to 3f high, 

 invested with wool. Lvs. somewhat clasping, woolly and hairy, armed with stiff 

 spines. Hds. large (1' diam.), with yellowish white corollas, the scales webbed. 

 Aug. 



/3. Elliotttl Corollas purple, 2' long. Bracts about 12. — South (Elliott). Fla., 

 near Qaincy. 



4 C. Pitcheri, Torr. & Gr. White-tomcntous ; lvs. rigid, pinnately parted, mar- 

 gins revolute, segra. long, linear, toothed or entire, spinous ; lids, axillary ; scales 

 arachnoid, acuminate, tipped with a weak, spreading prickle. — Sandy lake shores. 

 Mich, and Can. West. Cor. ochroleucous. Jn., Jl. 



5 C. discolor Spreng. Lvs, sessile, pinnatifid, rough-haired, downy beneath, 

 eagm. 2-lobed, divaricate, spinous; invol. globous, the scales ovate, appressed, 

 with spreading spines at the lip. — (2) A slender thistle 3 to 5f high, much branch- 

 ed and leafy at the summit, found in thickets, N. Eng. to 111. lids, termini.tir.2 

 the branches, 1 ' diarn., with reddish purple corollas. Jl. Aug. 



