PYRROCOMA. C0MP'»SIT/E 299 



serrulate, the cauline partly clasping: heads numerous, 6-8 lines high, 

 sessile and somewhat clustered along the branches: bracts of the involu- 

 cre oblong, obtuse, mucronate: rays 10-12, slender: achenes slightly hairy 

 toward the summit. Plains of the Columbia near Walla Walla. Washing- 

 ton 



P. arguta T &G 1 c Glabrous. Stems 10-12 inches high: leaves 

 spatulate-lanceolate, somewhat acuminate, sharply serrate, the cauline 

 partly clasping : heads axillary and terminal, clustered, sessile, bracts of 

 the involucre lanceolate, acute : rays 10-12, usually infertile. Plains of 

 the Columbia near v> alia Walla. Washington. 



• P glomerata T & G 1. c. Glabrous, ^tem simple or branched: 

 leaves obi ng lanceolate or the lower spatulate-lanceolate; very acute, 

 mostly entire, the cauline partly clasping : heads 6 lines long, nearly as 

 broad, clustered and disposed in an interrupted spike: rays 8-10, usually 

 fertile. Plains of the Columbia near Walla Walla, Washington. 



P. congesta Greene Pitt, iii; 2 : Glabrous throughout except a 

 scanty pubescence about the inflorescence: stems rather slender, 1 »— 80 in- 

 ches high, several from the thick ligneous root, ascending, simple, leafy 

 below, floriferous from belovs the miodle : radical leaves lanceolate, acute 

 at both ends, entire, the blade 3-4 inches long, on a slender petiole as long; 

 cauline smaller, tapering to a small winged petiole Heads clustered in 

 the axils of all the re luced cauline leaves: involucre campanulate, 4-n lines 

 high, its bracts rigid oblong, .{-nerved, with acute green tip- : pappus 

 tawny, of coarse very unequal bristles: only the outer disk flowers fertile, 

 the achenes of these oblong, appressed pilose : abortive achenes of ray and 

 inner disk densely silky-pubescent. • n dry hillsides, western base of the 

 Coast mountains near Waldo, Oregon 



P. hirta Greene Eryth, ii, 69 Aplopappus hirtu* Gray. Hirsutely pu- 

 bescent and villous, even to the involucre, or at base lanuginose: stems 8- 

 12 inches high, rather simple ascending, bearing few or scattered pedun- 

 culate heads : leaves membranaceous, pectinately serrate with long and 

 salient slender-subulate teeth: cauline an inch or two long: radical some- 

 times 4 inches long and with margined petioles: involucre hemispherical, 

 half inch or more high, its b acts rather loose, linear, acuminate or acute, 

 all about equalling the disk, the outer mainly foliaceous: rays 2«i or more 

 conspicuous: achenes rather short, sericeous-pubescent: pappus o , 

 whitish. < astern regon and Washington 



P. Howellii Greene 1. c. 70 Aplopappus Howellii Gray. ericeous- 

 tomentose : stems 6-1 inches long ascending branching from the base: 

 leaves all narrowly lanceolate, acute, entire or rarely denticulate : heads 

 solitary, terminating the stem an branches, rather few-flowered involu- 

 cre 6-10 lines high, its bracts linear, rather obtuse, all of equal length: 

 rays conspicuous ; style appendages long and slender: achenes oblong-lin- 

 ear, nearly as long as the rigid pappus, pubescent. On dry ridges, Grain 

 (reek, Eastern Oregon. 



P. laneeolata Aplopappus lanceolatus 1*. & G. stems 0-24 inches high 

 at first lanuginose, at length nearly glabrous: leaves coriaceous the radical 

 and lowest cauline lanceolate, acute irregularly spinulose-toothed, peti 

 oled : the upper small and bract like, linear-lanceolate, partly clasping: 

 heads 2-5 : involucre hemispherical, its bracts lanceolate-oblong, charta- 

 eous v unequal, imbricated: rays 2- '-25 pistillate : style appendages lanceo- 

 late acute a out the length of the stigmatic portion : achenes silky. Idaho 

 to British Columbia and the plains of the Saskatchewan. 



P. Hallii Aplopappus HaUii Gray. Glabrous throughout: stems 12- 

 20 inches high, paniculately branched from a suffrutescent or even more 

 woody base, very leafy : leaves lanceolate or linear, 8-12 lines long by 2-3 

 lines broad rather rigid, mostly scabrous on the margins, midrib promi- 



