258 University of California Publications in Botany. [VOL. 3 



specimens, near Caliente, Kern Co., the pappus-bristles are dis- 

 tinct to the base. 



5. S. myrioclada Eat., Bot. King Exped. 198, t. 20, figs. 1 to 

 4 (1871). 



Branches ascending, very slender: rameal leaves all reduced 

 to scales 1 cm. or less long : heads sometimes only 3 or 4-flowered 

 and involucral bracts reduced to 3 or 4: otherwise as in 8. run- 

 cinata, of which it is probably only a form. 



Piute Creek, eastern San Bernardino Co. or western Nevada. 

 Jun. 5, 1893, N. C. Wilson; Yosemite Valley, 1893, /. B. Lem- 

 bert; first collected in Nevada by Watson, ace. to Eaton. 



6. S. virgata Benth., Bot. Sulph. 32 (1844). Ptiloria virgata 

 Greene, Pitt. ii. 130 (1890). 



Stems rigid, virgate or with usually virgate branches, some- 

 times widely and paniculately branched, 3 to 20 or even 40 dm. 

 high: herbage usually glabrous: lower leaves oblong or spatu- 

 kte, often sinuate or pinnatifid; upper leaves linear, small and 

 entire : heads subsessile along the naked branches, mostly 4 to 

 16-flowered : involucre 7 mm. high : ligules reddish-purple on the 

 back, lighter on the upper surface, sometimes clear white : achenes 

 svibclavate or oblong, longitudinally ribbed, the intervening spaces 

 more or less rugose and traversed by a deep narrow groove : 

 pappus clear white, plumose almost throughout, fragile but the 

 base commonly persistent. 



On the plains and in the foothills, very common throughout 

 the Upper Sonoran Zone in Southern California, including the 

 islands; north to Oregon, east to Utah. Jul.-Sept. This species 

 attains its greatest development at San Diego, where there is also 

 a puberulent form. Here the flowers are commonly 14 to 16, not 

 rarely 20 to 22 in a head. 



Var. pleurocarpa (Greene) Hall, comb. nov. Ptiloria pleuro- 

 carpa Greene, Pitt. ii. 131 (1890). Achenes light-colored, the 

 spaces between the ribs either plane or rugose but not grooved: 

 pappus deciduous. With the species on Mt. San Jacinto, at 

 Riverside, Pomona, Cucamonga, Santa Monica, and north. In 

 some plants, otherwise typical S. virgata, the pappus is decid- 

 uous ; on others both light and dark-colored achenes may be found. 



