Aster. COMPOSITE. 323 



* 



2. Perennials (?) ivith leaves spinulosely pinnatiftd-toothed or incised (or sometimes 

 entire) : scales of the involucre with long-acuminate but not green tips : pappus 

 of comparatively few (20 to 35) and very rigid bristles. (Transition to Town- 

 sendia.) MEGALASTRUM, Gray. 



5. A. tortifolius, Gray (not Michx.). At first loosely white-woolly, when old 

 somewhat roughish-hirsute or glabrate, a foot or so high : branches naked and 

 peduncle-like at summit, bearing a solitary very large head : leaves coriaceous, 

 rigid, often twisted, oblong or lanceolate, veiny, strongly dentate or incisely pinnat- 

 itid with divaricate spinulose teeth : involucre hemispherical ; its very numerous 

 scales lanceolate-subulate and setaceous-acuminate, the outer a little shorter : rays 

 violet-purple, very numerous, an inch long : pappus becoming reddish. Proc. Am. 

 Acad. vii. 353. Aplopappus tortifolius, Torr. & Gray, in Bost. Jour. Nat. Hist. 



Mountains near the southeastern borders of California (Dr. Cooper) ; thence to S. Utah, Fre- 

 mont, Newberry, Mrs. Thompson. This and A. (Megalastrum) Wriyhtii, Gray, form a remarkable 

 section of the genus, which might almost as well be referred to Townsendia. Style-appendages 

 short, obtuse. Akenes (young) linear-oblong, silky- villous. Bristles of the pappus about 

 20 in a single series, strong, flattish, serrulate-scabrous, nearly equalling the disk-corolla, and a 

 few slender and shorter ones intermixed. 



3. Perennials, with leaves merely serrate or entire. ASTER proper. 



* Pappus rather rigid, some of the longer bristles thickened towards the summit : in- 

 volucre campanulate or turbinate ; its scales very regularly imbricated in many 

 ranks, rigid, with short green or greenish tips, the outer successively shorter. 



6. A. radulinus, Gray. Roughish-pubescent throughout : stem rather stout, 

 one or two feet high, branching above and bearing an open corymb of middle-sized 

 heads : leaves rigid and coriaceous, oblong, or the lower obovate-spatulate, sharply 

 serrate above, tapering below into a narrowed entire base, prominently reticulate- 

 veiny, scabrous both sides, the midrib very prominent beneath : peduncles short : 

 involucre obconical, 4 or 5 lines long ; its scales rigid, appressed, lanceolate or ob- 

 long, obtuse or abruptly pointed or mucronate, more or less glandular-pubescent, 

 the tips mostly green : rays 15 to 18, white (perhaps not always so) : akenes mi- 

 nutely pubescent. Proc. Am. Acad. viii. 388. A. Radula, Less, in Linnaea, vi. 

 125 ; Durand & Hilgard PL Pratten., not of Ait. 



Dry open ground, Monterey to Mendocino Co. (thence to Oregon, E. Hall) : also in the Sierra 

 from Nevada Co. northward, Torrey, Lemmon. This is nearly related to A. conspicuus, Lindl., 

 of the region much farther north, a plant with larger heads and leaves, while the smaller 

 forms are more like A. nwntanus, equally a northern species. 



* * Pappus softer and equable. 

 -*- Low and diffuse : branches leafy to the top and bearing small mostly single heads. 



7. A. Bloomeri, Gray, 1. c. Cespitose, a span or less in height, minutely cine- 

 reous-hirsute, and near the heads somewhat glandular : branches ascending : leaves 

 oblong-linear or the lower spatulate, 3 to 10 lines long, obtuse, entire, very rough 

 both sides with the short minutely hispid pubescence, the uppermost passing into 

 scales of the involucre ; these 25 to 30, linear, acute, glandular and greenish : rays 

 12 to 15, apparently purple, about 4 lines long : akenes minutely pubescent. 



Moist flats near Mount Davidson, Nevada (probably also within the State boundary), Bloomer, 

 Lemmon. Heads 4 lines long. 



+- -t- Stems erect and branching, leafy, bearing several or numerous commonly panicu- 

 late or racemose heads : involucre imbricated, 



*+ Its scales many-ranked, close, and with short green tips. 



8. A. Menziesii, Lindl. Minutely hoary with a fine (either soft or scabrous) 

 pubescence, or glabrate below, a foot or two high : stem and branches virgate, rigid : 



