24G COMTOSITVE. (compositk family.) 



75. RUGELIA, Shutfl. 



Heads many-flowered, the flowers all tubular and perfect Scales of the cam- 

 panulate involacre lanceolate, equal, in a single row. Receptacle convex, naked. 

 Corolla 5-clcft. Style bulbous at the base, the long branches truncated at the 

 apex, and besel with rigid reflexed hairs. Achenia terete, striate. Pappus of 

 numerous rather rigid rough bristly hairs. — A perennial herb, with alternate 

 undivided haves, and large heads in a simple corymbose raceme. 



1. R. nudicaulis, Shuttl. Minutely pubescent; rhizoma creeping ; stem 

 simple, erect ; leaves ovate, acute at each end, denticulate ; the lowest ones large 

 (2' -4'), crowded, on long margined petioles, the others small, scattered, and 

 nearly sessile ; heads on long bracted peduncles. — Smoky Mountains, Tennes- 

 see, Rugel, Buckley. — Stem 1° high. 



76. ARNICA, L. 



Heads many-flowered, radiate; the rays pistillate. Scales of the campanulate 

 involucre lanceolate, equal, in about two rows. Receptacle flat, hairy. Achenia 

 terete, narrowed downward, somewhat ribbed. Pappus a single row of rough 

 bristly hairs. — Perennial herbs. Leaves opposite, undivided. Heads single or 

 corymbose. 



1 • A. nudicaulis, Ell. Hirsute ; radical leaves spreading, oval or oVm 

 ovate, obtuse, 3 - 5-ribbed, serrate or entire; the others (2-3 pairs) distant, 

 oblong, sessile ; heads corymbose, showy; achenia snioothish. — Wet pine bar- 

 rens, Florida, and northward. April and May. — Stem l°-2° high, simple, or 

 with few opposite branches. 



Trihe V. CYNARE-35. Heads discoid; the flowers all tubular; the txterior 

 ones sometimes enlarged and ray-like : style thickened at the summit ; the stigmatic 

 lines extending to the summit of the branches, without apjiendages. 



77. CENTAUREA, L. Star-Thistle. 



Heads many-flowered ; the marginal flowers mostly large and sterile. Scales 



of the involucre imbricated. Receptacle bristly. Achenia compressed. Pappus 



of rough bristles in one or more rows, sometimes wanting. — Herbs. Leaves 

 alternate. Heads solitary. 



l. C. Calcitrapa, L. Stem diffusely branched, hairy; leaves pinnately 

 lobcd ; the lobes linear, toothed ; heads sessile ; involacre spiny ; pappns none. 

 — North Carolina. Naturalized. — Flowers purple. 



78. CIRSIUM, Tonni. THISTLE. 



Heads many-flowered, discoid ; the flowers all similar and perfect. Scales of 

 the involucre imbricated in many rows, all but the innermost one- usually Bpine- 

 pointed. Receptacle bristly, Achenia oblong, compressed, smooth. Pappns of 



numerous plumose hairs. — Herbs, with alternate sessile or decurreiit mostly 

 pinnatifld and spiny leaves. Heads large, Bubglobose. Flowers purple or 

 whitish. 



