142 SELECTED WESTERN FLORA 



10. APLOPAPPUS. 



Heads radiate, many-flowered, rays pistillate, disk flowers perfect; 

 involucre hemispherical, of several layers of linear bracts; leayes 

 alternate, rigid, dentate or lobed; pappus of 1-3 rows of more or 

 less unequal bristles. Rather low branching perennial herbs with 

 heads in which both ray and disk flowers are yellow. 



1. A. spinuldsus, Pursh. 



Slightly pubescent ; ' leaves pinnately , or sometimes bi-pinnately parted, 

 the lobes bristle-pointed; bracts of the involucre bristle-pointed; achene, 

 pubescent. Dry prairie, Man.-Alta. 



2. A. lanceolatus, T. and G. 



Stem, 4-8 in. high, erect or ascending, usually somewhat leafy, the upper 

 leaves bract-like; leaves lanceolate to oblong, the basal petioled; heads 

 3-15 in a raceme or panicle; bracts of the involucre of 3 or 4 rows, sharp, 

 dry, and white at the base with green tips. (Pyrrocoma lanceolata, (Hook.) 

 Greene.) Moist alkaline prairie, Man.-Alta. 



3. A. Huttallii, T. and G. 



Stem, simple, erect, 4-12 in. high, usually in clumps from a strong perennial 

 root; leaves lanceolate to spatulate, the lower usually petioled, the upper 

 sessile, rather stiff, sharply dentate, the teeth sometimes ending in soft 

 spines; heads solitary on the ends of stems or branches; bracts narrow and 

 spreading, the outer shorter ; aohene soft-hairy. (Sideranthus grinddioides, 

 (Nutt.) Brit.) Dry soil, S. Sask. 



4. A. aciulis, Gray. 



Dwarf, tufted, from a much divided woody erect rootstock; leaves 

 spatulate to linear, stiff and persistent, mostly tufted at the base, but a few 

 along the scape-like flowering stems, which are' not more than 5 in. high; 

 heads usually solitary, many-flowered ; bracts sharp, not green on the tips. 

 Dry clay or gravel ridges, S. Sask. 



11. CHRYSOPSIS. Golden Aster. 



Heads many-flowered, radiate; rays numerous; all flowers per- 

 fect; involucre of several rows of linear overlapping bracts ; pappus 

 a double row of bristles, the outer somewhat chaffy, the inner 

 longer and hair-like; flowers yellow. Low, branching, perennial 

 herbs with alternate, entire, sessile flowers. 



