COMPOSITAE. 247 



bud ; involuci e campanulate ; bracts herbaceous, in several series ; 

 receptacle flat or convex; akenes linear, 8-10-ribbed or striate; 

 pappus of white soft bristles. 



Ptilocalais nutans (Geyer) Greene. Perennial, from one or more fusiform 

 tubers, simple or branched, puberulent or glabrous, 10-40 cm. high; leaves 

 10-20 cm. long, lanceolate or linear-lanceolate, rarely oval, sometimes entire, 

 usually laciniate-pinnatifid into numerous linear lobes; peduncles stout and 

 elongated; heads 8-20-flowered; involucre oblong or turbinate-campanulate, 

 2 cm. long, the larger 8-10 bracts lanceolate, attenuate-acuminate; pappus 

 of lS-20 soft white plumose bristles, broadened at base, as long as the columnar 

 akenes. Common on hillsides. 



366. NOTHOCALAIS. 



Perennials with linear-attenuate wavy radical leaves with 

 white-tomentulose margins; heads solitary on scape-like pe- 

 duncles; involucre campanulate; bracts in 2 rows, narrowly 

 lanceolate, nearly equal; receptacle flat; akenes fusiform, con- 

 tracted or beaked at the summit, 10-ribbed; pappus white and 

 soft, of scabrous-margined unequal scales. 



Nothocalais troximoides (Gray) Greene. Nearly acaulescent from a stout 

 vertical root; leaves tufted, linear-lanceolate, long-attenuate, thickish, pale 

 or somewhat glaucous, glabrous or nearly so, 10-15 cm. long; scapes 15-30 

 cm. high; involucre 2 cm. high, the bracts lanceolate, subequal, glabrous; 

 akenes fusiform, not beaked, 8-10 mm. long; pappus bright white, longer than 

 the akene. Locally abundant, especially in adobe soils. 



367. UROPAPPUS. 



Stemless or short-stemmed herbs, with milky juice; leaves 

 mostly radical, often pinnatifid; flowers yellow, the heads ter- 

 minal, on scapes or long peduncles, mostly nodding before 

 flowering; receptacles without chaff or bristles; pappus chaffy 

 or plumose; corollas in all the flowers of the head ligulate; 

 akenes 8-12 ribbed. 



TJropappus linearifolia (DC.) Nutt. Annual, branched at the base, 15-40 

 cm. high; leaves lanceolate, 10-15 cm. long, mostly pinnatifid into linear lobes, 

 loosely pubescent when young, becoming glabrous; peduncles stout, glabrous, 

 striate-grooved ; involucre cylindric, 2.5-3 cm. high, glabrous, the bracts of 

 two lengths, lanceolate, acuminate; akenes fusiform, attenuate upwards, 

 10-12 mm. long; pappus silvery, as long as the akenes, consisting of five 

 linear scales, abruptly terminating in shorter awns. In loose rocks, banks of 

 Snake River. 



368. TARAXACUM. 



Acaulescent biennials or perennials, with milky juice; leaves 

 radical, pinnatifid; heads large, on scapes; flowers yellow; re- 

 ceptacle flat, naked; involucre of 2 rows of bracts; pappus of 

 copious and white-capillary bristles which are not plumose; 

 corollas all ligulate; akenes oblong or fusiform, angled, about 

 10-ribbed, attenuate at base, with a long filiform beak at the apex. 



