HUXFLOWEK FAMILY. 509 



most bracts erect; flowers bright crimson; corolla-segments longer 

 than the throat; pappus-bristles barbellate above, the tips scarcely 

 dilated. — (Carduus venustus Greene.) 



Higher hills and mountains of the Coast Eanges from Ukiah and 

 the Vaca Jfountains to Berkeley, Mt. Diablo and southward to 

 Forest Grove and Skyland in the Santa Cruz ilountains. June- 

 July. A strikingly handsome species passing by numerous gradations 

 into C. occidentale. The spreading bracts are frequently developed 

 into grappling-hook-like appendages nearly 1 in. long. 



13. C. occidentale (Nutt). Stout, 1^ to 3 ft. high, very white 

 "with thick coating of cottony wool; leaves from sinuate-dentate t<> 

 pinnatifid, not very prickly, glabrate above, canescent beneath; heads 

 subglobose, IJ to 1| in. high on nearly naked peduncles; involucral 

 bracts straight and subulate-lanceolate, with short spines, not widely 

 spreading, densely festooned with cobwebby hairs; flowers red or 

 purple; corolla-segments longer than the throat; anther-tips narrow 

 and acuminate; pappus rather scanty. — (Carduus oceidentalis Nutt.) 



Common on sandy hills near the coast, from San Prancisco south- 

 ward. The bracts, excepting their spiny tips, are quite concealed by 

 the dense wool. Even at a short distance from the sea the characters 

 are, however, less pronounced, the involucres being less arachnoid- 

 woolly and the bracts somewhat curved or diverging from the 

 appressed base; proceeding inland to the middle Coast Eanges, one 

 comes to typical C. Coulteri, with nearly or quite glabrous involucres 

 and characteristic bracts. This form is repeated about ilt. Shasta 

 and in the northern Sierra Nevada but the heads and whole plant are 

 almost snow-white woolly, when it is Carduus candidissimus Greene. 



22. SILYBUM Giertn. 



Annual or biennial herb with very ample sinuate-pinnatifid prickly 

 clasping leaves, smooth and shining above and very conspicuously 

 blotched with white along the veins. Heads very large, solitary at 

 the ends of the branches. Flowers purple. Corollas with filiform 

 tube conspicuously dilated below the narrowly linear lobes. Bracts 

 of the involucre broad, appressed, bearing an abruptly speading spine 

 which is broadly lanceolate or ovate and ciliate-prickly toward the 

 base. Pappus-bristles in several series, flattish, minutely barbellate. 

 (Old Greek name applied to thistle-like plants.) 



1. S. Marianum Gasrtn. Milk Thistle. Branching, 3 to 6 ft. 

 high; leaves IJ to 2J ft. long, 6 to 12 in. wide, strongly undulate at 

 the sinuses; heads about 2 to '2i in. broad; spines of the middle in- 

 volucral bracts 1 to IJ in. long. 



Common in abandoned fields and by roadsides throughout Califor- 

 nia. Naturalized from the Mediterranean Kegion. May-Aug. 



Tribe 3. Senecioneae. Groundsel Tribe. 



23. PETASITES Gajrtn. Sweet Coltsfoot. 

 Perennial herbs with creeping rootstoeks from which arise in early 



