Cnicus. COMPOSITE. 417 



where Bentham has placed these genera, although the bristles of the pappus are somewhat too 

 stout and tlattish. 



1. R. scaposa, I rray. Somewhat hirsute as well as glandular : scape a span to 

 a foot high, sometimes with a leaf or two towards the base : involucre 20 — 30-flow- 

 ered (an inch or less long). 



Sierra Nevada, in the Yosemite and Mono districts, at the elevation of S,000 to 10,000 feet, 



/.v. >r. ,; Bohiiid. /-, fjruy. 



2. R. ai'gentea, Gray. Leaves shorter, only one or two inches long, silvery- 

 silky : scape "lie to four inches high: involucre narrower, 7 — 15-flowered (half an 

 inch or more long). 



Higher Sierra Nevada, at 8,000 to 11,000 feet : Mount Dana to Sonora Pass (Brewer, Bolandcr), 

 above Uonner Lake (£. L. Greene), and on Lassen's Peak, Lemmon, 



Tribe IX. CYXAROIDE.E. 



The only Californian representatives of the tribe are Thistles, of well-known 

 appearance, and a Centaurea or two, of the Mediterranean region, sparingly natural- 

 ized in fields and around harbors. Even Burdocks are unknown. 



Cynara Si olymus, Linn., the Artichoke of the Old World, — remarkable for the thick fleshi- 

 ness of the receptacle and scales of the involucre, which are edible, — is occasionally spontaneous, 

 probably escaped from cultivation. 



104. CNICUS, Linn. ' Thistle. 



Head many-flowered; the flowers all perfect and fertile, with tubular corollas 

 deeply (often more <t less unequally) 5-cleft into narrow lobes. Involucre globular, 

 ovoid, or at maturity sometimes campanulate ; the mostly narrow scales imbricated 

 in many series, more commonly tipped with a spine or cuspidate point. Recep- 

 tacle flat, fleshy, densely clothed with bristles. Filaments commonly papillose- 

 hairy, distinct : anthers sagittate at base, the auricles frequently extended into tails. 

 Style filiform, sometimes thickened or with a pubescent ring or node at the base i>f 

 the minutely puberulent stigmatic portion : which in our species is almost always 

 slender, consisting of two filiform branches which are more or less firmly united by 

 their inner faces up nearly or quite to the tip. Akenes glabrous and smooth, thick- 

 walled, obovate or oblong, more or less compressed, attached by their very base. 

 Pappus of copious and rather rigid long and plumose bristles in a single series, con- 

 nected at the very base into a ring, so that tiny remain united after detaching. 

 Not rarely the bristles of some of the outermost flowers are slightly or nol at all 



plumose. — Stoul herbs, mon mmonly biennials, with alternate and usually 



prickly leaves, and large or middle-sized heads; the flowers purple, red, pale yellow, 

 or white. — Benth. & Hook Gen. PL ii. 468 j Gray, Proa Am. Acad. \. 39. 

 Cirrium, Tourn., I X '. Prodr., &c. 



A largo genus, widely dispersed over the northern hemisphere, most numerous in the "M 

 World. It seems necessary to follow Bentham in restoring the Liunrean name of Cnicus, includ- 

 ing, however, a good deal more than the Oirsium of Cassini, De Candollo, \r. Two European 

 species, which ire common and ti lublesomc in the Atlantic States, seeni not i" have > 



i .iIiImi in i, viz. — 



C. lani eoi sirs, the common Field Thistle, which is well runrked by the leaves being decur- 

 rent "ii the stem, and their upper surface very harsh or almost prickly. 



C. m:\t\sis, the Canada Thistle (but not indigenous I , with numerous small heads 



which incline to bo die i 



