416 COMPOSITAE. 



Bracts of involucre linear to subulate, narrowly or not obviously scarious-margined, little 

 imbricated. 

 Branching, mostly glabrous; heads 3 to A lines bigh. 



Flowers white or pinkish; pappus not persistent 1. M. obtusa. 



Flowers yellow; one pappus-bristle persistent 2. M. clevelandii. 



Acaulescent, long-woolly when young; heads 6 to 8 lines high 3. M. calif or nica. 



Bracts of involucre scarious, with green midrib, distinctly imbricated, the outer orbicular; 

 branching and glabrous plant 4. M . coulteri. 



1. M. obtusa Benth. Stem paniculately branching above the base, 4 to 16 

 in. high, nearly naked; radical leaves dentate or pinnatifid, the margin often 

 bearing scattered tufts of wool; heads small, numerous; involucre about 3 

 lines high, its main bracts linear, acuminate and nearly equal, with a few 

 short ones at base, the tips usually purplish (as also in the next) ; achenes 

 obovate-oblong, the summit entire, none of the pappus-bristles persistent. 



Higher mountain slopes of the Coast Ranges and south to Santa Barbara 

 Co. ; also in the Sierra Nevada. May-July. 



2. M. clevelandii (hay. Slender, */> to 1% ft. high, glabrous throughout; 

 radical leaves pinnatifid, the cauline scattered and more nearly entire; panicle 

 ii;ii row; heads 3 lines high, few-flowered; achenes oblong-linear, minutely 

 si riate-costate; outer pappus of one persistent bristle and a circle of white 

 setulose teeth. — (M. parviflora Greene, not Benth.) 



Antioch and plains bordering the eastern base of the Mt. Diablo range, 

 south to Southern California. Apr.-May. 



3. M. calif ornica DC. Acaulescent; scapes 4 to 6 in. high, each bearing 

 one rather large head; herbage conspicuously woolly when young with very 

 long and soft hairs; leaves laciniately pinnatifid into narrowly linear or almost 

 filiform lobes; involucre 4 to 6 lines high, its bracts narrowly linear or subulate, 

 in about 3 ranks; bristles of the receptacle delicate, usually present; achenes 

 narrow, lightly striate; outer pappus of 2 persistent bristles and some inter- 

 vening minute teeth. 



Sandy soil: Antioch to Monterey Co. and southward to Southern California. 

 Apr.-May. 



4. M. coulteri Gray. Snake 's Head. Simple or branching from the base, 

 5 to 10 in. high, the herbage glabrous and glaucescent ; cauline leaves sinuately 

 pinnatifid, broad or somewhat auriculate at the sessile base and with an 

 elongated terminal lobe; heads subglobose, % to 1 in. broad; bracts of in- 

 volucre silvery-scarious with a linear central portion green, regularly imbricated 

 in several ranks, the short outer ones orbicular, the inner oval to lanceolate or 

 linear; achenes 15-ribbed and 4 or 5-angled, the summit obscurely denticulate 

 by projection of the ribs; 1 or 2 stouter pappus-bristles persistent. 



Frequent in the lower San Joaquin Valley; southward to Southern Cali- 

 fornia. Apr. 



12. HIERACIUM L. Hawkweed. 



Ours rough-hairy perennial herbs with entire or nearly entire leaves and 

 the heads in a panicle. Involucre cylindric or campanulate, its main bracts 

 in 1 to 3 ranks with shorter ones at base. Achenes linear, striately ribbed, 

 not beaked. Pappus a single row of tawny or dull white fragile capillary 

 bristles. (Creek hierax, a hawk.) 



1. H. albiflorum Hook. Stem nearly naked above, ending In a panicle of 

 white-flowered heads, l'_. to •"> ft. high; leaves and lower portion of stem 

 thickly beset with tawny bristly hairs; leaves mostly radical, oblong, narrowed 

 at base to a winged petiole, or the upper cauline sessile and often lanceolate 



and Linear; involucre 3 or I lines high, its bracts linear-subulate; achenes 

 reddish brown, !'■_■ lines long; pappus dull white. 



