314 COMPOSITE MACH^RANTHRA 



BRACHYACTIS 



pinnatifid or rarely entire leaves and solitary or corymbosely or 

 racemosely disposed heads of purple-rayed flowers. Heads many 

 flowered, the rays numerous, in a single series, pistillate; those 

 of the disk tubular and perfect, with 5 short erect teeth. Bracts 

 or the obovoid or turbinate involucre closely imbricated for the 

 most part in several series, linear rigid, somewhat carinate, un- 

 equal, with herbaceous squarrose-spreading or recurved tips : re- 

 ceptacle flat, somewhat alveolate ; the alveoli toothed or lacerate. 

 Style-appendages filiform subulate or linear-lanceolate, minutely 

 hirsute. Achenes turbinate or cuneiform, often compressed, 

 pubescent or silky. Pappus of numerous scabrous and rather 

 rigid very unequal bristles. 



M. Shastensis Gray Proc. Am. Acad, vi, 539. Aster' Shastensis Gray. 

 Canesont with a close scurfy tomentum : stems slender, 4-8 inches high 

 from a perennial root, paniculately branched : leaves linear-spatulate to 

 linear, 1-2 inches long with a few teeth near the middle : heads rather nu- 

 merous, scattered, 5-6 lines high: bracts of the involucre linear, acute: the 

 outer ones shorter and often with spreading tips : rays 12-20, violet 3-6 

 lines long: style appendages elender-subulate: pappus simple and soft: 

 achenes narrow, hardly at all compressed, silky-pubescent. Southeastern 

 Oregon (Camp Polk) to Northeastern California. 



M. eradiata Aster Shastensis var. eradiatus Gray. Whole plant some- 

 what glaucous and canescently puberulent : stems stoutish, 6-10 inches 

 high from a stout perennial root : leaves oblanceolate 1-2 inches long, 2-6 

 lines broad, attenuate below to a margined petiole, obtuse or acutish min- 

 utely apiculate, entire or sparsely serrate : heads? rather numerous, 4-5 

 lines high : bracts of the involucre linear, acute, in 3-4 ranks, the outer 

 successively shorter and more subulate: rays wanting: achenes sparsely 

 pubescent. On high rocky ridge of the Siskiyou and Scott's mountains. 



M. attenuata. Whole plant cinereous : stems stoutish, 1-2 feet high 

 from a large perennial root : cauline leaves linear, reduced above to sub- 

 ulate bracts, all acute and apiculate : heads numerous terminating in the 

 branchlets : involucre hemispherical, its linear bracts well imbricated in 

 several series, the outer successively shorter and passing into the ordinary 

 bracts of the branchlets, the inner ones attenuate above to a slender bris- 

 tle: rays dark purple, numerous 5-6 lines long: style appendages slender- 

 subulate : pappus simple, of soft capillary bristles : young achenes silky- 

 canescent. On sandy plains and banks near The Dalles, Oregon. 



20 d BRACHYACTIS Ledeb. Fl. Ross, ii, 495. 



Annual or perennial low herbs with mostly* entire leaves and 

 solitary or racemose-paniculate heads of inconspicuous flowers. 

 Heads many-flowered heterogamous ; the rays very numerous 

 and occupying more than one series, fertile. Involucre loosely 

 imbricated, in few series of herbaceous bracts or the innermost 

 somewhat scabrous.. Receptacle .flat, naked. Style appendages 

 lanceolate. Achenes more or less compressed. Pappus simple of 

 copious fine and soft capillary bristles. 



B. frondosa Gray Proc. Am. Acad, viii, 647. Aster frontlo$u& G. & T. 



Glabrous or nearly so: stems 1-1 2 inches high or more from an annual 

 r"ox)t branching from the base : "eaves spatulate linear, 1-2 inches long, the 

 uppermost passing into the invoiueral bracts, the lower attenuate below 



