298 COM POSI yM pyrrocoma 



erous, pistillate, sometimes infertile or inconspicuous : disk-flow- 

 ers cylindrical, slightly dilated upward, with short erect teeth. 

 Style-branches of the ray-flowers often unequal, or one of them 

 abortive, glabrous: those of the disk-flowers subulate-linear, 

 elongated, the hispid appendages much longer than the stigmatic 

 portion, Achenes linear, elongated, somewhat 3-angled and 

 striate glabrous or rarely hairy. Pappus reddish-brown or ful- 

 vous, of copious and uniform slender rigid bristles 



* Heads large and discoid the sterile rays being hardly apparent 

 or very small for the size of the head ; achenes glabrous and suiooth, 

 slender but flattish, 4-costrtte or nerved often finely striate 



P. ciirthamoides. Hook- Fl. i, -iOe. t. 107. s^ten s rigid several from 

 the same root, ti-12 inches high, leafy, -cabro puberulert when young, be- 

 coming smooth, bearing a solitary terminal large head and sometimes one 

 or two in axils: leaves from spatiilate to oblong or lanceolate: coriaceous, 

 sparingly spinulose-.serrnlate the lowest :(-+ inches long, tapennginto slen- 

 der petioles: involucre hemispherical, o-li' lines high, often leafy- 

 subtended at base, its proper bracts coriaceous rigid, from oblong to 

 br.jadly lanceolate or the innermost linear, more or less scarious-margm- 

 ed. most of them tipped with an abrupt mucro or cusp, the outer com- 

 monlv loose and becoming leaf-like either entire or spinulofe-denticulate : 

 rays almost alwavs present and rather uumerons. but their ligules incon- 

 S]iiciinus, being short involute and concealed in the pappus On plains and 

 roeky hillsides; British Columbia to O egon an<l Idaho. 



P. radiata N'utt Trans. \m. I'jiil. Soc n. ser, vii .3S3. Whole plant 

 glalnMis: stem stout, 1'2-18 inches high: leaves thick, the radical and lower 

 oanliiie obovate-oblong.ihe lowest 3-(-i inches lona by -' inches broad, petio- 

 led the upper cauline ovate-lanceolate or obUmg ; heads nsuaily several ■ 

 and somewhat corymbose, an inch high and broad, bracts of the invo- 

 lucre n.inierous. broad or hroadish : rays very narrow, exserted but incon- 

 spicuous: achenes 4 lines long, about the lengih of the rigid expanding 

 papiUis, the bristles of which are barbellate-scabrous I iry plains near 

 "Walla Walla, AVashington 



P. '"usickii ("xreene Eryth. ii, n^ Aplop'tppas en Hh "inoides Var. Ciis- 

 ichii Gray Stems 6-18 inches high ascending few-leaved : leaves mostly 

 spatulate-lanceolate : heads comparatively small and few-flowered, termi- ' 

 nal and sublerminal : bracts of the involucre rather few, lanceolate, most- 

 ly aiute or acuminate. Union County, Oregon Cusick. 



•i * Heads middle-rsized to small, evidently radiate; the exserted 

 rays often infertile Vmt styliferous 



P. raceiuosa i . & G. Fl ii, -.'44, Stems glabrous, 12-18 inches high, 

 bearing S-7 racemose heads at the summit ; leaves glabrous, lanceolate, 

 slightly spinulose-serrate, the upper acute, Dblong-lanceolate, partly clasp- 

 ing, the lower tapering to the base, somewhat petioled : heads hemispher- 

 ical, less than an , inch in diameter: involucre Imbricated, in 3 series its 

 ovate oblong scales pubescent; ray-flowers conspicuous and fertile; disk 

 corollas shorter than the pappus : achenes sparsely hirsute. I'laiiis of 

 the I'olumbia. 



* * Heads obovoid, sessile and often clustered : involucre as long 

 as the disk, the scales linear-oblong, with short distinct herbaceous 

 tips imbricated in se-^eral series: achenes glabrous. 



P. pauiculata T & (i 1 c. Glabrous. >tems a foot high, branched at 

 the summit: leaves oblong-lanceolaie. mucronate, obscurely and remotely 



