ANTENNABIA. COMPOSITE 327 



29 ANTENNARIA Gartn. Fruct. & Sem. ii, 410, t. 167. 



Dioecious or polygamo-diuecious perennial herbs with alternate 

 leaves and many-flowered heads of inconspicuous flowers. Heads 

 discoid ; the pistillate flowers with filiform truncate corolla shor- 

 ter than the 2-cleft style; staminate with tubular 5-lobed corolla 

 and style with undivided truncate apex. Involucre of imbrica- 

 ted, scarious, persistent bracts, at least their tips white or colored'. 

 Receptacle flat or convex, naked. Achenes small, nearly terete 

 or flattish, mostly glabrous. Pappus a single series of capillary 

 bristles, those of the fertile flowers very slender, connate at base, 

 and so falling from the achene in a body; those of the sterile of- 

 ten crisp, mostly thickened at -the apex. 



1 Bristles of the pappus of the staminate floweas hardly at 

 all thickened, but minutely barbellate near the apex : achenes 

 obscurely 2-3-nerved, pubescent, the short hairs with 2-lobed 

 and at length biuncinate tips. Bracts of the campanulate or 

 somewhat turbinate involucre brownish. 



A. dimorpha T. &G. Fl. ii, 431. Depressed, cespitose, forming dense 

 matted tufts from a few inches to a foot or more in diameter and only an> 

 inch or two high : the thickish rootstocks creeping : stems 1-2 inches high,, 

 very leafy : leaves spatulate, attenuate below to a petiole, 6-12 lines long 

 whitish-tomentose both sides : heads solitary, 3-4 lines high : bracts of the 

 involucre well imbricated, the outer successively shorter and obtuse, the- 

 inner acute or acuminate ; of the fertile heads narrow with hyaline acum- 

 inate tips: achenes oblong, pubescent: pappus of the fertile flowers copi- 

 ous, of soft and very slender bristles that are not at ail thickened upward. 

 Common on dry plains east of the Cascade mountains, Brit. Columbia to 

 California and the Rocky Mountains. 



A. flagellaris Gray Proc. Am. Acad. xvii, 212 Silky-lanate : stem sol- 

 itary, 6-20 lines high, from a slender rootstock : lower leaves subulate- 

 frorn a very broad and somewhat clasping base, producing from their axils 

 slender wiry stolons 2-6 inches long, with a tuft of leaves and a bud at 

 their apices which root and form new plants : cauline leaves linear, 10-14 

 lines long, not at all narrowed at base: heads solitary, 3-4 lines high : 

 bracts of the involucre in few ranks, but little unequal, acute or the inner 

 ones shortly acuminate. On barren rocky ridges in the mountains of eas- 

 tern Oregon and Washington. 



A. stenophylla Gray 1. c. "Stems erect from a subten anean caudex, 

 slender, 4-6 inches high, without stolons, leafy, terminated by a capituli- 

 form glomerule of 2-4 heads : leaves very narrowly linear or almost filiform, 

 attenuate to both ends (the larger 3 inches long), silvery- woolly : heads 

 barely 3 lines long : involucral bracts in both sexes broadish and obtuse, 

 dark brown, or in the male the inner ones with white tips : achenes (two 

 thirds of a line long), minutely hirtellous-scabrous : female pappus scanty, 

 only a line long: * *. High hills Union Co. eastern Oregon Cusick. " 



2 Bristles of the staminate pappus stout, with clavate or 

 scarious-dilated tips. 



* Not surculose by stolons, 6-12 inches high : pistillate heads nar- 

 row, cylindraceous or clavate : achenes glandular. 



A. Geyeri Gray PI. Fendl. 107. Pubescence appressed silk y-canescent: 

 stems numerous from a lignescent branched base, 3-8 inches high : leavea 



