370 COMPOSITAE. 



508. OREOSTEMMA. 



Acaulescent perennial herbs with solitary heads on scapi- 

 form stems and entire leaves; heads broadly hemispheric; tegules 

 herbaceous, narrow, subequal, rather loose, in about 2 series; 

 receptacle flat; ray-flowers numerous, violet to purple; style 

 branches slender, acute, hirsutulose; akenes prismatic, villous; 

 pappus a single series of denticulate capillary bristles. 



Oreostemma alpigena (T. & G.) Greene. Caudex and root stout; 

 stems spreading or ascending, 5-10 cm. high, scape-like, the leaves much re- 

 duced; basal leaves spatulate to linear, obtuse, entire, glabrous, 3-8 cm. long; 

 involucre hemispheric, 12 mm. high; tegules linear, acute, somewhat pubes- 

 cent; ray-flowers violet, 12-15 mm. long; akenes hirsute at the summit. 



At high altitudes in the Cascade Mountains. First collected on Mount 

 Rainier by Tolmie in 1833. 



509. BUCEPHALUS. 



Perennial herbs; leaves alternate, all cauline, the lowermost 

 much reduced; heads panicled, rarely solitary, radiate; involucre 

 well imbricated, campanulate; tegules chartaceous, closely 

 appressed, arranged in 3 or 4 series, the outer successively 

 shorter; receptacle lacerate-alveolate ; ray-flowers in a single 

 series, violet or white; disk-flowers yellow; style branches lan- 

 ceolate; akenes compressed; pappus copious, of numerous 

 unequal bristles. 



Ray-flowers white, becoming pink-tinged. E. paucicapitatus. 

 Ray-flowers purple or violet. 



Leaves tomentose beneath. E. ledophyllus. 



Leaves glabrous on both sides. E. engelmanni. 



Bucephalus paucicapitatus (Robinson) Greene. Stems tufted, erect, leafy, 

 30-50 cm. high, somewhat pubescent; leaves elliptic-oblong, puberulent, 2-3 

 cm. long, erect or ascending; heads mostly solitary, sometimes 3 or 4, short- 

 peduncled, 3-3.5 cm. broad; tegules lance-linear, pubescent, ciliolate, acute, 

 purple at tip, loosely imbricated in 2-3 series, 8 mm. long; ray-flowers 12-18, 

 white becoming pink. 



Common in alpine meadows of the Olympic Mountains, but not known to 

 occur elsewhere. 



Bucephalus ledophyllus (Gray) Greene. Stems usually tufted, erect, 

 30-80 cm. high; leaves numerous, lanceolate, entire or sparsely denticulate, 

 glabrous above, tomentose beneath, 2-5 cm. long, the lower obtuse, the upper 

 cuspidate; heads solitary or several in a loose cyme; tegules lance-linear, acute 

 or acuminate; ray-flowers violet; akenes sparsely hirsute. 



Alpine meadows in the Cascade Mountains, southern British Columbia to 

 Oregon. 



Bucephalus engelmanni (Gray) Greene. Nearly glabrous; stems 60-90 

 cm. tall, erect; leaves oblong-lanceolate to ovate-lanceolate, thin, entire or 

 more or less serrulate, 5-10 cm. long, the upper ones cuspidate; heads race- 

 mosely or paniculately cymose; involucre hemispheric; tegules ovate-lanceo- 

 late, acute or acuminate, the outer loose and partly foliaceous, the inner 

 purplish; ray-flowers purple, 10-12 mm. long; akenes oblong-obovoid. 



Alpine meadows in the Cascade Mountains, mostly on the eastern slopes. 



