Cr* A «*] SYNGENESIA 437 



Root biennial. Stem 2 to 4 feet high, stout, erect, branching, striate-sulcate, 

 hairy, winged by the decurrent leaves. Leaves 4 to 8 or 12 inches long, and I to 2 

 or 3 inches wide (the radical ones much larger than the cauline), prickly-hispid on 

 the upper surface, lanuginous beneath. Heads terminal, erect, ovoid, about an 

 inch in diameter; leaflets of the involucre lanceolate, sharply spinose at apex, 

 connected by a cobweb-like villus. Florets purple, with yellowish anther*. 

 Akenes small, compressed, obovate-oblong, smooth ; pappus about an inch long, 

 silky, plumose. 

 Hab. Pastures ; along fence-rows, &c. common. Fl. June— July. Fr. July— Aug. 



Obs. An introduced and troublesome weed,— delighting in a rich soil, and re- 

 quiring some attention to keep it in subjection. 



2. C. dtscolor, Nuit. Leaves sessile, linear-lanceolate, more or less 

 deeply pinnatifid, snioothish and green above, densely hoary-tomentose 

 beneath, the segments ciliate and spinose ; leaflets of the involucre 

 lance-ovate, appressed. Beck, Bot. p. 173. 



Cnicus discolor. JVilld. JWuhl. Florid, Cestr. &c. 



TWO-COLOHKI) CaKDUUS. 



Root biennial. Stem 2 to 5 feet high, with rather slender spreading branches, 

 gtriate-sulcate, somewhat pubescent with crisped membranous hairs. Leaves 3 

 or 4 to 12 or 15 inches long, deeply pinnatifid, the segments linear-lanceolate, and 

 lance-oblong, cuspidate and spinose-ciliate,— the under surface bluish-white with 

 a soft dense tomentum. Heads terminal, erect, ovoid-oblong, 1 to 2 inches long, 

 and an inch or more in diameter ; lower leaflets of the involucre lance-ovatc, upper 

 or inner ones linear-lanceolate, all appressed, somewhat arachnoid-villose, and 

 terminating in slender spreading spines. florets reddish purple, with whitish 

 anthers. 



Hab. Old fields ; borders of thickets, &c. frequent. Fl. Aug-Sept. FY. Sept-Octo. 



3. C. pumtlus, Nutt. Stem low and retrorsely pilose, few-flowered ; 

 leaves semi-amplexicaul, lance-oblong, pinnatifid, green on both sides, 

 the segments irregularly lobed, spinose-ciliate and pointed with sharp 

 spines ; involucre large, the leaflets ovate-lanceolate, acuminate, appres- 

 sed, terminating in a short spine. Beck, Bot, p. 173. 



Cnicus pumilus. Torr. Comp. p. 282. 



C. odoratus. Muhl. Catal. p. 70. Bart. Phil. 2. p. 95. Floral. 



Cestr. p. 85. Eat. Man. p. 100. 



Dwarf Oarduus. 



Plant pale greyish-green. Root biennial (perennial, Muhl). Stem 1 to 2 feet 

 high, stout, erect, or subdecumbent, sparingly branched, striate, hairy. Leaves 

 4 to 12 or 15 inches long, and 1 to 2 or 3 inches wide (the radical ones large), more 

 or less hairy, densely pilose on the midrib beneath. Heads 1 to 3, terminal, round- 

 ish-ovoid, very large (1 to 2 inches in diameter), often with pinnatifid spinose bract- 

 like leaves at base ; leaflets of the involucre nearly naked, appressed,— the lower 

 ones ovate lanceolate, acuminate, with rather short subulate spines,— the upper 

 ones long, lance-linear, acuminate, not spinose, serrulate near the apex. Floret* 

 often 2 inches in length, of a rather pale reddish purple, with whitish anther*. 

 Pappus an inch to an inch and half long. 



Hab. Old fields; Mica-slate hills : frequent. FL July. Fr. August. 



Obs. The flowers of this species are quite fragrant ; and the heads rather hand- 

 som«,— being the largest of any of our native thistles. 



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