COMPOSITvE 



15. TOWNSENDIA. 



145 



Flowers radiate; rays long, in a single series, usually fertile; disk- 

 flowers perfect, the tubes 5-tootlied; branches of the style hairy 

 towards the end; scales of the involucre rather large, dry, and some- 

 what fringed on the margins, often tinted; pappus of many stout 

 bristles ; achenes flattened. Stemless tufted herbs with large heads 

 and pink, purplish, or white rays. 



1. T. ezscSpa, (Richards) Porter. 



Stemless or almost so, 1-3 in. high from a strong perennial root; leaves 

 all clustered at the base, linear or narrowly spatulate ; heads solitary, 

 sessile, large, exceeded by the leaves; rays white or purplish; pappus a 

 single row of rigid bristles, that of the ray-flowers shorter. (7*. sericea, 

 Hobk.) Dry soil, W. Sask. to Rocky Mts. 



16. Aster, astbr. 



Heads radiate, many-flowered; ray-flowers pistillate, variously 

 colored; disk-flowers tubular, perfect, usually yellow, turning dark; 

 pappus usually of a single row of sleiider bristles. Mostly perennial 

 branching herbs with alternate leaves and showy heads of flowers 

 (generally white or some shade of purple) ; usually flowering late in 

 the season. A very large and difficult genus. 



1. A. Lindleyanus, T. and G. 



Glabrous or nearly so, 1-2 ft. high; lower leaves broadly ovate, more 

 or less cordate at the base; the upper sessile, pointed at both ends; ray- 

 flowers blue. Thickets, Man.-Alta. 



2. A. umbelUtus, Mill. 



Stout, 2-S ft. high, smooth or nearly so, leafy up to the flowers; leaves 

 lanceolate to oblong, tapering at both ends; ray-flowers white; pappus of 

 two rows of bristles, the inner long and hair-like, the buter short and rigid; 

 heads numerous, arranged in a flat corymb. Moist thickets or poorly 

 cultivated ground, Man. and Sask. 



3. A. commut&tus, (T. and G.) Gray. 



Somewhat hoary-pubescent, low and bushy; leaves small, linear, entire 

 crowded, the upper passing gradually into bracts; rays 20-30; heads small, 

 crowded on the branches; flowers white. Dry sandy soil, Man.-Alta. 



4. A. multifldrus. Ait. 



Rays 10-20; same as the preceding except that the heads are smaller, 

 Dry soil, local, Man.-AIta. 



