384 COMPOSIT A CARDUUS | 
innocuous with more scarious and sometimes obviously dilated and erose- 
fimbriate tips: corollas white to rose-purple, with lobes usually shorter 
than the throat. From the Arctic sea-shore to California and the Rocky 
Mountains. 
C. foliosus Hook. Fl. i, 303. Stems-.erect, robust, striate, somewhat 
woolly, leafy to the cluster of a few sessile heads, 12-18 inches high: 
leaves commonly elongated, linear-lanceolate, laciniately dentate, with 
rather rigid prickles, arachnoid-tomentose beneath: heads broad, inch and 
a half high leafy-bracteose: involucral bracts thin-coriaceous: corollas pale 
or white, with lobes equalling or longer than the throat. Idaho to the 
Rocky Mountains. 
+ + + Heads large or comparatively small: involucral bracts 
closely appressed, coriaceous or thickish, commonly with a glandular 
or viscid ridge, short line, or broad spot on the back near the summit. 
C. undulatus Nutt. Gen. ii, 130. Persistently white-tomentose, 1-4 
feet high: leaves lanceolate or oblong-lanceolate, sessile or decurrent, or 
the lowest petioled, undulate, lobed or pinnatifid the lobes dentate, trian- 
gular, often very prickly: heads about 2 inches broad, nearly as high, soli- 
tary at the ends of the branches: principal bracts of the involucre mostly 
thickened on the back by the broad glandular-viscid ridge, comparatively 
narrow, tipped with short spreading. prickles: corollas rose color or pale 
purple to white, with lobes equalling or longer than their throats. Dry 
prairies, Brit. Columbia to Oregon, New Mexico and Lake Huron. 
Var. megacephalus Greene |. c. Stouter, usually broader-leaved ; 
with broad heads 2 inches or more high. Idaho to Minnesota and Texas. 
C. Brewcri Greene 1. c. 363. Usually white-tomentose, 4-10 feet high : 
leayes mostly elongated-lanceolate, conspicuously prickly : heads panicu- 
late, sometimes very numerous, subsessile, an inch or more high: bracts 
of the globular inyolucre much appressed, firm coriaceous, with an oblong 
or oval greenish viscid-glandular spot near the tip; outer ones ovate to 
oblong, abruptly tipped with a rather slender spreading prickle: corollas 
pale purple or whitish, the lobes shorter than the throat. Moist places, 
southern and eastern Oregon to California and Nevada. ' 
90 SILYBUM Geertn. Fr. ii, 308. (Mick Taistie) 
Annual or biennial herbs with large alternate clasping sinuate- 
lobed or pinnatifid white-blotched leaves, and large discoid heads 
of purple tubular flowers, solitary at the ends of the branches. 
involucre broad, subglobose ; its bracts rigid, imbricated in many 
series, the lower ones fimbriate-spinulose at the broad triangular 
summit, the middle ones similar but armed with stout spreading 
or recurved spines; the inner ones lanceolate. Receptacle flat, 
densely bristly. Corollas with slender tube and deeply 5-c'eft 
limb. Filaments united below, glabrous. Anthers sagittat2 at 
base. Style nearly entire. Achenes obovate-oblong, compressed, 
glabrous, surmounted by a papillose ring. Pappus-bristles in 
several series, flattish, barbellate or scabrous. 
S. Marranum Gertn. |. c. 378. Stout, 2-4 feet high, little branched, 
glabrate or glabrous: leaves oblong-lanceolate, prickly, sinuate or pinnati- 
tid, the lower often a foot long, green blotched with white along the veins: 
heads about 244 inches broad: corollas rose-purple, deeply cleft: pappus- 
bristles white, barbellate. Waste places and road-sides, Brit. Columbia to 
California. Naturalized from Europe. 
