COMPOSITE FAMILY. 



195 



spinescent at apex. Receptacle flat, fimbrillate or bristly-cLaffy. Corolla 

 5-cleft — the limb thick at base, half as long as the tube, the lobes very 

 unequal. Akeivs obovate compressed or 4-sided, smooth. Pappus in 

 several series, long, plumose — the bristles free at base, but attached to 

 a deciduous ring. Perennial spinose herbs. Leaves alternate, pinnati 

 fidly lobed, not decurrent. Heads large, with a thick flesliy receptacle. 



1. C. Scoltm'us, L. Stem branching; leaves subspiuose, bipinnatifid 

 and sometimes undivided, tomentose beneath ; scales of the involucre 

 ovate, thick and fleshy at base, obtuse at apex and somewhat eniargi- 

 nate — rarely subspinescent, straight or slightly divergent. 

 Artichoke. 



Ft. Artichaud. Germ. Die Artischoke. Span. Alcachofa. 



Root perennial. Stem 3-5 feet high, stout, striate and tomentose. leaves large, entire 

 or lobed and spinose. Heads ovoid, 2-3 inches in diameter ; florets blue or violet-purple. 

 Gardens : cultivated. Native country uncertain. Fl. Aug. Fr. Sept. 



Ohs. The thick receptacle, together with the fleshy bases of the scales 

 of the involucre, affords a favorite vegetable dish, — for which this plant is 

 cultivated. Another species, called Cardoon (C. Cardunculus, L.), with 

 the leaves all bipinnately lobed, and more spinose, to which the foregoing 

 is nearly allied (if, indeed, it be not, as Prof. De Candolle suggests, a 

 mere variety produced by long culture) , is also cultivated for the thick 

 fleshy petioles and ribs of the leaves, which are rendered delicate and 

 white by etiolation, or blanching, after the manner practiced with 

 Celery. 



25. CIR'SIUM, Tournef. Thistle. 



[Greek, Kirsos, a varix, or enlarged vein ; for ^vhich the plant was a supposed remedy.] 



Heads many-flowered ; florets all similar and perfect, or rarely imperfectly 

 dicEcious. Involucre subglobose ; scales imbricated in numerous series, 

 mostly cuspidate or tipped with a spine. Receptacle fimbrillate. Akenes 

 oblong, compressed, not ribbed, glabrous. Pappus of many series, the 

 hairs united into a deciduous ring at base, plumose, merely denticulate 

 (the stouter ones slightly clavellate) at apex. Biennial or perennial herbs. 

 Leaves alternate, sessile or decurrent, often pinnatifid with the margins 



j and segments spinose, — the radical ones much larger than the cauline, as 



t is usual with biennials. 



^ Involucral scales all tipped with spreading prickles. 



1. C. lanceolo'tum, Scop. Leaves decurrent on the stem and forming 

 a spinose lobed wing, pinnatifid, prickly hispid on the upper surface, 

 cobwebby beneath — the segments lanceolate, bifid, divaricate, spinose ; 

 involucre ovoid, nearly bractless ; scales linear-lanceolate, tipped with a 



j spine, the outer ones spreading. 



I Lanceolate Cirsium. Common Thistle. 



k 



Fr. Chardon lanceole. Germ. Die Kratzdistel. Span. Cardo. 



