198 COMPOSITE. 



the heads subulate, but obtuse, commonly ending in a large saucer- 

 shaped gland. Receptacle small, flat, the chaff herbaceous and only 

 encircling the disk flowers. Bays 15, white or yellow, vespertine, 

 palmately 3-lobed or -parted; the head as a whole narrow and small. 

 Ray-achenes obovoid-triangular, the terminal areola nearly central. 

 Disk-achenes turbinate-quadrangular, the outer fertile, all bearing a 

 conspicuous chaffy pappus. 



1. C. truncata, DO. Slender, 12 ft. high, glabrous, or some of the 

 lower leaves sparsely hispid; herbage keenly benzine-scented, though 

 rigid and dry: heads sessile and scattered along the virgate branches: 

 short uppermost leaves and bracts truncate by a large sessile flattish 

 gland: fl. yellow; rays 5 (rarely more); disk-fl. 10 24; receptacle-chaff 

 distinct, or nearly so, truncate: pappus of disk-achenes of 7 10 oblong 

 fimbriate-toothed pointless palese. Dry hills of Marin, Sonoma and 

 Napa counties. July Oct. 



2. C. cephalotes, DO. Stem simple, or with few ascending branches, 

 % l/^ ft- high: herbage sweet-scented: few-flowered heads densely glom- 

 erate and sessile at the summit and in all the upper axils: small floral leaves 

 densely hispid-ciliate : involucral bracts 13, only a third the length of 

 the cup of the receptacle : fl. white, with a reddish tinge, ray-achenes 

 with prominent turgid angles and faintly rugose sides: disk-achenes 

 appressed-villous, their pappus as long as the achene and of about 8 

 chaffy scales which are alternately acuminate-pointed and pointless. 

 Marin to Napa Co., and northward. June Aug. 



42. BLEPHARIZOtfIA, Greene. Stout and rather coarse glandular- 

 viscid and hirsute heavy-scented annuals, with linear entire lower, and 

 oblong upper leaves. Ray-flowers 7 10, with 3-lobed white ligules. 

 Disk-flowers 10 30, the outer ones subtended by linear chaff. Achenes 

 silky-hirsute, 10-striate, those of the ray partly embraced by the involu- 

 cral bracts and without pappus; those of the disk surmounted by many 

 densely plumose awns. 



1. B. plnmosa (Kell.), Greene. Somewhat paniculately branching 

 from the base, the branches bearing, racemosely, many heads, these 

 15 20-flowered: ray achenes with a minute crown of short scales, those 

 of the disk 20 or more erect plumose bristles half as long as the achene. 

 Plains near Antioch. Aug. Oct. 



2. B. laxa, Greene. Larger, 36 ft. high, loosely paniculate above, 

 the large heads borne singly at the ends of the branches, 20 25-flowered : 

 pappus of ray- and disk-achenes alike, short and spreading, less plumose 

 than in the preceding, only a fifth as long as the achene. Habitat of 

 the other species. 



43. ACHYRACHISNA, Schauer. Soft-pubescent sparingly branching 

 annual, with narrow leaves, and rather large oblong-campanulate seem- 



