402 ASTERACEAE. 



Rays when present pistillate. Disk-flowers perfect, 

 5-toothed. Achenes terete or those of the marginal 

 flowers somewhat compressed, 5-10-ribbed, papillose or 

 canescent and usually emitting a pair of spiral threads 

 after wetting. Pappus copious, of white scabrous or 

 smooth capillary bristles. 



Annuals, glabrous or nearly so. 



Rays none. 1. S. vulgaris. 



Rays present. 2. 5. californicus. 



Perennial herbs or sufFrutescent, more or less 

 floccose-woolly. 

 Rays none; leaves dentate. 3. S. astephanus. 



Rays present; leaves at least the lower pin- 



nately parted into narrow lobes. 4. 5. douglasii. 



1. S. vulgaris L. Annual, puberulent or glabrate; stems slightly 

 fleshy, 1-3 dm. high, more or less branched; leaves clasping at the 

 base, pinnatifid, the lobes and sinuses sharply toothed; heads 7-9 

 mm. high; bracts black-tipped; rays none; achenes slightly canescent. 



Common in neglected gardens and yards. Flowering throughout 

 the year. Native of Europe. 



2. S. californicus DC. Annual, glabrous or becoming so, slender 

 1.5-4 dm. high; leaves lanceolate in outline, varying from denticu- 

 late to pinnatifid, the lobes short and obtuse, all but the lowest 

 sessile and auriculate-clasping, 2.5-5 cm. long; involucre 6-8 mm. 

 high, its bracts narrow; rays oblong, 6-8 mm. long, light yellow; 

 achenes canescent. 



Common in sandy soil in dry places in our interior valleys and 

 foothills, and on the sand-dunes along the seashore. February- 

 May. 



3. S. astephanus Greene. Stems erect, from a biennial or 

 perennial root, 5-10 dm. high, very floccose-woolly, at length glabrate 

 above; basal leaves thin, 2-3 dm. high, elliptic-oblong, acute at 

 both ends, coarsely dentate, the teeth spreading, triangular, callous, 

 tipped, the sinuses rounded and the larger denticulate, lower leaves 

 resembling the basal, the uppermost narrow, lanceolate, entire or 

 irregularly dentate; heads 1-2 cm. broad, less than 1 cm. high; 

 6-10 in a close cluster at the ends of the peduncles; rays none- 

 flowers all fertile. ( S. ilicetorum Davidson.) 



Wilson's trail at 2500 feet altitude, Davidson. 



4. S. douglasii DC. Suff'rutescent, usually about 1 m. high, 

 branching from the base, whitish-tomentose or becoming glabrate; 

 lower leaves pinnately divided into about 5 narrowly linear lobes, 

 the uppermost entire, all with revolute margins; heads rather few, 

 corymbose, 10-15 mm. high; rays light yellow, 10 mm. long; achenes 

 hoary with a short pubescence. 



Common on dry plains and foothills, mostly below 3000 feet 

 altitude. July-November. 



