CORETHROGYNE. COMPOSITiE. 99 



first woolly-canescent, at length nearly glabrous ; achenia cuneiform-oblong, 

 compressed; silky-pubescenl. — Nutt. ! I.e. Aster? filaginifolius, Hook.Sf 

 Am.! bat. Beechey, p. 146. Diplopappus leucophyllus, Lindl. in DC. 

 prodr. 5. p. 278? 



iMonterey, California, Capt. Beechey! St. Barbara, Nuttall! — Plant more 

 slender and branched than the preceding, a]jparenily slightly suffruticose at 

 the base ; the pubescence similar, but looser and more deciduous. Heads 

 smaller; the scales of the involucre fewer, and not glandular or viscid. Pap- 

 pus of the ray almost none. Young achenia turbinate and silky-canescent ; 

 when mature coinpressed and minutely silky-pubescent. The style resem- 

 bles that of the preceding species. 



4. C. tomentella: stein shrubby at the base; the branches slender, woolly, 

 leafy to the summit; leaves (of the branches) appressed, linear or linear- 

 oblong, closely sessile ; those of the short branchlets or peduncles crowded, 

 very small and bract-hke. passing info the ohlong obtuse tomentose scales of 

 the somewhat turbinate involucre; achenia silky-canescent. — Aster? tomeu- 

 telliis. Hook. ^' Am. ! hot. Beechey, p. 146. 



Monterey, California, Capt. Beechey! (v. sp. in herb. Hook.) — We have 

 seen but a single and imperfect specimen, vvhich has still smaller heads 

 than C. filaginifolia : the oblong or slightly spatulate scales of the involucre 

 are pretty closely imbricated in 4 or 5 series, and gradually pass into the 

 very short bract-like leaves of the branchlets; they are somewhat mem- 

 branaceous, obtuse, but often slightly mucronulate ; the tips somewhat 

 spreading. The leaves of the branches are small, densely v.'ooUy ; the upper 

 oblong ; the lowest linear ; those of the proper stem unknown. 



24. DIETERIA. Nutt. in trans. Amer. phil. sac. 7. p. 300. (excl. spec<) 



Heads many-flowered ; the ray-flowers numerous (10-30), in a single se- 

 ries, pistillate ; those of the disk tubular, perfect. Scales of the obovoid or 

 turbinate involucre closely imbricated for the most part in several series, 

 linear, rigid, somewhat carinate, unequal, with herbaceous squarrose-spread- 

 ing or recurved tips. Receptacle flat, somewhat alveolate ; the alveoli 

 toothed or lacerate. Rays linear; the corolla of the disk cylindraceous, often 

 narrow, 5-toothed. Appendages of the style filiform-subulate or linear-lan- 

 ceolate, minutely hirstUe. Achenia turbinate or cuneiform, often compressed, 

 pubescent or silky. Pappus of numerous scabrous and rather rigid capillary 

 bristles, very unequal (in 2 or 3 series) ; that of the ray similar but frequently 

 shorter and less copious. — Annual, biennial, or triennial herbs (natives of 

 arid or naked plains between the Mississippi and the Pacific), divaricately 

 branched, canescent or pulverulent-pubescent, or sometimes viscid. Leaves 

 rarely entire, usually jiinnalely toothed or pinnatifid, narrow; the cauline 

 sessile. Heads (often large) solitary or several on the corj^mbose or race- 

 mose branches. Rays purple or violet, rarely ochroleucous ; the disk-flow- 

 ers yellow. Pappus tawny or brownish. 



§ 1. Scales of the involucre imbricated in several series, with short herbaceous 

 tips : leaves usually rigid, spinulose-loothed or jnnnatijid, sometimes entire ; 

 the cauline Linear, the radical lanceolate or spatulate {rays pistillate, but 

 sometimes infertile ?). — Dietkria proper. 



