320 COMPOSITE. Sericocarpvs. 



short and more or less spreading green tips, imbricated ; the outer successively 



shorter. Eeceptacle small, alveolate-toothed. Style-appendages lanceolate-subulate. 



Akenes narrow, little if at all compressed, silky-pubescent or villous (whence the 



generic name). Pappus simple, of copious capillary bristles. — Perennial Aster-like 



herbs, with corymbed and rather small heads ; the disk- flowers pale yellow, and 



the rather small rays white. 



A genus of three species of the Atlantic United States, and of the following on the Pacific 

 side of the continent. 



1 . S. rigidus, Lindl. A foot or two high, scabrous with some very short and 

 rigid pubescence, or almost glabrous, leafy to the top : leaves oblong-lanceolate, 

 acute or obtuse, entire, an inch or two in length : heads half an inch or less in 

 length : rays narrowly oblong, sometimes not exceeding the white pappus : akenes 

 slender, clothed with fine short pubescence. — S. Oregonensis, Nutt., the state with 

 rays conspicuous. 



In woods, base of Mt. Shasta (Brewer), Yosemite Valley (Bolander), and near Donner Lake 

 (Torrey) ; extending to Washington Territory. 



20. CORETHROGYNE, DC. 



Head many-flowered, heterogamous ; the rays numerous in a single series, neutral ! 

 Involucre hemispherical or turbinate ; the scales narrow, mostly with green or green- 

 ish and more or less spreading tips, imbricated in several series, the exterior mostly 

 shorter. Eeceptacle flat, naked or somewhat alveolate, rarely with some chaff simi- 

 lar to the innermost involucral scales interposed among the outer flowers. Anthers 

 tipped with a slender cuspidate appendage, as in Lessingia. Style-appendages short, 

 triangular-lanceolate or subulate, densely beset with long hispid bristles, forming 

 a brush-like tuft (whence the generic name). Akenes and pappus of the ray abor- 

 tive or rudimentary, of the disk compressed like those of Aster, silky-villous or 

 pubescent : the pappus simple, of rather copious but rigid and unequal capillary 

 bristles. — Eather low Aster-like herbs, apparently always perennial, branched 

 from a somewhat woody base or rootstock, more or less white-woolly at least when 

 young ; the alternate leaves serrate with some sharp or coarse teeth towards the 

 apex, or entire ; heads middle-sized, solitary terminating the branches or somewhat 

 corymbose-panicled : rays violet, purple or blue : disk yellow, sometimes changing 

 to purple : pappus becoming tawny or reddish. — Torr. & Gray, Fl. ii. 97 ; Gray in 

 Bot. Mex. Bound. 76, & Proc. Am. Acad. vii. 251. 



De Candolle's character of chaff on the receptacle applies only to Douglas's specimens of the 

 original 0. Calif ornica; and in those it is not constant ; so that the species must include C. incana, 

 Nutt. Then all those with smaller and (when well developed) corymbose-panicled heads appear 

 to belong to one species which blossoms through the season and under different exposures : some 

 of the forms gathered and described were winter states. The genus is a particularly well-marked 

 one, most related on the one hand to Lessingia, on the other to Aster. 



* Bristles on the style-tips forming a rather scanty and small tvft : involucre cam- 



panulate or turbinate. 

 1. C. filaginifolia, Nutt. Stems erect or ascending, about a foot high, com- 

 monly branching corymbosely or paniculately at the summit and bearing several or 

 numerous rather small heads : leaves oblanceolate or narrowly spatulate, the upper 

 gradually reduced to subulate bracts : involucre (4 lines long) between turbinate 

 and campanulate ; the numerous scales appressed, or with only the short greenish 

 tips scpuarrose-spreading, the outer regularly shorter, all glabrous or at first more or 



