522 COMPOSITAE (COMPOSITE FAMILY) 



less, 3-7 cm. long: heads fully 12 mm. high and broad; bracts of the involucre 

 not very unequal, usually pubescent, linear, acute: rays purple, 12-16 mm. 

 long: style-appendages linear-subulate: achenes linear, striate, glabrate below, 

 hirsute near the top. (Aster pulchellus Eaton, Bot. King's Exp. 143. 1871.) 

 In the higher mountains; Wyoming and Montana to Washington. 



25. IONACTIS Greene 



Low tufted perennials, often lignescent at base, never stoloniferous or with 

 radical leaves. Stems clothed equably with narrow, entire, rigid, 1-nerved 

 and veinless leaves and terminating in 1 or more showy heads with violet 

 rays. Involucre of well imbricated bracts of coriaceous texture, without 

 herbaceous tips, appressed even to the tips. Achenes narrow, villous. Pap- 

 pus double, the more copious inner series bristly, the outer short and setulose. 



1. lonactis alpina (Nutt.) Greene, Pitt. 3: 245. 1897. Puberulent and 

 somewhat cinereous; stems tufted, rigid, only 9-15 cm. high, terminated by 

 a solitary pedunculate head: leaves short, 6-12 mm. long, rigid, oblong 

 to linear or the lowest spatulate, the broader obtuse with an abrupt mucro, 

 callous-margined: involucre broadly campanulate; the bracts imbricated in 

 about 3 series, scabro-puberulent, lanceolate: rays 10-12 mm. long, light 

 violet: outer pappus sometimes distinctly chaffy. Aster scopulorum. In the 

 mountains of Montana and Wyoming and thence far westward. 



26. LEUCELENE* Greene 



Low perennials with diffusely branching leafy stems from a slender lig- 

 neous base. Leaves numerous, subulate and appressed, or more spreading 

 and nearly linear. Heads small, solitary, and terminal upon the nearly fili- 

 form ultimate branchlets. Involucres turbinate, imbricated; the bracts 

 narrow, nearly plane, herbaceous but with narrow, scarious margins. Rays 

 and disk both white or the former reddish or at least often turning red in 

 drying. Disk-corollas tubular-funnelform, 5-toothed but not deeply so; style- 

 tips ovate, acutish. Achenes long and slender, manifestly compressed, hir- 

 sutulous. Pappus a single series of long and slender, scabrous, bright- white 

 bristles. 



1. Leucelene ericoides (Torr.) Greene, Pitt. 3: 148. 1896. Usually only 

 8-14 cm. high, canescent and glandular-scabrous, much branched; branches 

 erect or diffuse, terminated by somewhat pedunculate heads: leaves commonly 

 hispid-ciliate, erect or little spreading, 6-12 mm. long; the lowest spatulate and 

 tapering into a petiole; the upper linear to nearly filiform: bracts of the in- 

 volucre in about 3 series, lanceolate, acute or apiculate, thinnish, scarious- 

 margined: rays white or sometimes rose-color. Aster ericaefolius. Dry hills; 

 Wyoming and Utah to Kansas and Texas. 



27. ERIGERON L. FLEABANE. ERIGERON 



Branching or scapose herbs, with alternate or basal leaves, and corymbose, 

 paniculate, or solitary pedunculate heads of both tubular and radiate (rarely 

 all tubular) flowers. Involucre hemispheric or campanulate; the bracts nar- 

 row, nearly equal, imbricated in but 1 or 2 series in our species. Receptacle 

 nearly flat, usually naked. Ray-flowers, in our species, white, violet, or purple, 

 or rarely yellow, pistillate; disk-flowers yellow, tubular, perfect, the corollas 

 mostly 5-lobed. Anthers obtuse and entire at the base. Style-branches more 

 or less flattened, the appendage^ short, mostly rounded or obtuse. Achenes 

 flattened, usually nerved. Pappus-bristles fragile, slender, scabrous or den- 

 ticulate, in 1 series, or often an additional outer shorter series. 



* This genus is essentially monotypic. Several species have been proposed but they rest 

 on characters shading imperceptibly into each other. These species are L. arenosa Heller, 

 Cat. N. A. Plants S. 1900 (.-later ericaefolius tennis Gray); L. alsinoides Greene, Pitt. 

 4: 99. 1899; L. hirtcllu Rydb. ( Diplopappus ericaefolius hirtella Gray); and L. serotina 

 Rydb. (L. ericoides serotina Greene), Bull. Torr. Bot. Club 33: 153. 1906. 



