ORDBa 10.— COMPOSITE. 467 



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

 10-bristled. — Oriental herbs. 



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

 spinous, woolly, bracteate. — (2 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. X § 



95. ONOPOR'DON, Vaill. 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. aoanthium L. Invol. scales spreading, subulate ; lvs. ovate-oblong, decurrent, 

 , sinuate, spinous, woolly on both sides. — @ 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. § Ear. 



96. CIR'SIUffl, Tourn. (Cnicus L. Muhl.) Thistle. (Gr. icipaog. 

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

 discoid, homogamous ; involucre subglobous, of many rows of .spi- 

 nous-pointcd, imbricated scales ; receptacle bristly ; stylo scarcely 

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

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

 cyanic. 



* Leaves decurrent on the stem more or less. Scales tipped M-itli spines No8. 1, 2 



• Leaves not decurrent. — Heads involucr.ato with a wliorl of 12 to 20 spiny bracts No. 8 



— Heads Halted. — l^'iowers ocljroleucons. Scales priclily No. 4 



— Fls. purple. — Lvs. wliitc-tomentous beneatli..Nos. 5 — 7 



— Lvs. green. — Stem low, simple. .Nos. 8, 9 



— Stem tall, branched, .No. 10 



1 C. lanoeolEitiim Scop. Common TmsTLB. Lvs. decurrent, pinnatifid, hispid, 

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

 tipped with a spine, spreading, — @ 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. Pis. numerous, large, purple. InvoL 

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



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

 more or less decurrent, with a few spinous teeth, glabrous above, white-floooous 

 beneath, invol. ovoid, arachnoid when young; scales not spinous, merely mucro- 

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

 more diam.) terminal. 



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

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

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

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

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

 Aug. 



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

 near Quincy. 



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

 gins revolute, segm. long, linear, toothed or entire, spinous ; hds. 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. Ims. sessile, pinnatifid, rough-haired, downy beneath, 

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

 with spreading spines at the tip. — @ A slender thistle 3 to 5f high, much branch- 

 ed and leafy at the summit, found in thickets, N. Eng. to III Hds. terminating 

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



