332 U(.)M rOSlT Ji Conyza. 



hirsute, thickly beset witli linear entire leaves, or those at the base broader and cut- 

 lobed : leaiy panicle generally long and narrow : pappus simple. 



Wiuitc and culliviUfil LNouiKis, everywhere having tlio aspect of na introduced weed, common 

 uhuobt nil over tlio worUl. 



24. CONYZA, Linn. 



Heads many -flowered, heterogamous, but not radiate ; the pistillate flowers in 

 many series and more numerous than the fertile ones, with only a filiform truncate 

 corolla shorter than the style ; the few central flowers tubular and perfect, or some 

 of them infertile. Involucre of narrow numerous scales, lieceptacle flat or convex, 

 naked. 8tyle-api>endages siiort. Akenes small, flattened, visually nerved only on 

 the margins. l'ai)[)us as in Erujtroii, in ours of simple scanty caj)illary bristles. — 

 Mostly tropical or subtropical weeds, with alternate toothed or lobed leaves, and 

 small corymbose or i)anicled heads of whitish or yellowish flowers. 



1. C. Coulteri, Gray. Annual (]), somewhat viscidly pubescent, one or two feet 

 high, very leaiy to the top : leaves closely sessile, linear-oblong or the lower spatu- 

 late, coarsely toothed or incisely pinnatitid, a])out an inch long : panicle narrow, 

 virgate : heads very numerous, small, barely 2 lines long : involucre hairy : central 

 perfect flowers 5 to 7. — Troc. Am. A(^ad. vii. iifif). C. suhdeairrem, (Jray, I'l. 

 Fendl. itc., not of DC. JCrigenm discoidta, KeUogg in Proc. Calif. Acad. v. .OS. 



S. E. borders of the State {Coulter, Cooper) ; on tlie Saii Joaquin {Kellogcj) ; and through Ari- 

 zona to Colorado and Texas. A homely weed. 



25. BACCHARIS, Liniu 



Heads many-flowereil, homogamons, diuicious ; in the sterile plant the flowers 

 seemingly perfect as to style &c., but with abortive ovary ; in the fertile pistillate 

 only. Involucre of dry imbricated scales, destitute of herbaceous tips, the exterior 

 successively shorter. Ifeceptacle commonly flat and naked. Corolla of the fertile 

 flowers small and filiform, truncate, wholly destitute of ligule, shorter than the 

 style : in the sterile flowers tubular with a somewhat expanded 5-cleft limb : the 

 style usually 2-cleft at summit, sometimes undivided. Akenes small, several-ribbed. 

 Pappus in the fertile flowers of copious mostly soft and fine capillary bristles ; in 

 the sterile commonly less coi)ious or less elongated, often tortuous and move den- 

 ticulate. — Shrubby or sometimes herbaceous plants, ours all glabrous, often gluti- 

 nous, with alternate leaves and small mostly clustered heads of white or yellowish 

 inconspicuous flowers. 



A very large genus in South America, a few reaching tlie United States throughout its southern 

 borders, and extending noithward along either coast. 



« Leaves broad, short and obtuse, commonly few-toothed : heads panicidate-glumerate 

 on the very numerous branches : paj>j)us in the fertile flowers at lenyth much exceeding 

 the involucre. 



1. B. pilularis, DC. Shrub | to 4 feet high, glutinous : leaves sessile, obovato 

 or cuneiform, about an inch long, coarsely or sinuately few-toothed, or occasionally 

 entire : heads 2 or 3 or more in a cluster from the axils of the upper leaves, globu- 

 lar, 2 or 3 lines long, the fertile pappus becoming 4 or 5 lines long. — B. pilularis 

 & £. consanguinea, DC. 



Common in sandy soil along the whole length of tlie coast, and reacliing Oregon ; flowering in 

 autumn. De Candolle's speeilic name may relate to the sixe nntl form of the lloweiing heads, or to 

 small globular excrescences, probably galls, which often occur on some branchlets. 



