New plants from Colorado 



George E. Osterhout 



r 



*^Allionia sessilifolia sp. nov. 



^ 



Perennial from the root, the stem rather stout, i;-io dm. hi<^h. 

 erect and branched above, angled, glabrous, but the branches 

 glandular-pubescent above; leaves thickish, all sessile, the lower 

 ovate, 6-8 cm. long, 4 cm. wide, rounded at base, the upper nar- 

 rower becoming smaller and bract-like ; inflorescence spreading, 

 the flowers numerous; involucre hirsute, 3-flowcred, the flowers 

 longer than the involucre; stamens about four, exserted ; fruit 

 4-5 mm. long, 5-ribbed, having short ridges between the ribs and 

 at right; angles to them. 



Allionia sessilifolia seems nearest related to A, pilosa (Nutt.) 



Rydb., but is readjly^istinguished by the glabrous stem and the 



ile Jeave^* Collected at Livermore, Larimer County, 



J 



^ Aster fluvialis sp, nov. 



Perennial from creeping rootstocks, the stem rather slender, 

 6-10 cm. high, leafy and branched from near the base, or in shade 

 or crowded vegetation more strict, slightly pubescent in lines ; 

 leaves lanceolate, tapering to both ends, sessile, the larger ones I 

 dm. long. I cm. w^ide, thin, entire, ciliate on the margins, some of 

 them usually with rare denticulations, becoming much smaller on 

 the leafy panicle ; inflorescence much branched and paniculate, the 

 the flowers numerous on the leafy branches; heads 7-10 mm. 

 long, or including the rays 1 5 mm. long ; bracts imbricated in 

 successive lengths of four series, close and erect, narrowly spatu- 

 late and green-tipped, scarious-margined ; rays varjnng from light- 



to dark-purple but never white. 



longifoliu 



latiis and seems to be nearer the latter, but is manifestly neither of 

 them. The flowers are larger than those of A, pamculaius, the 

 rays are never white, the leaves are entire and thinner, and the 

 stem is more branched. It is plentiful along the streams and 

 ditches of the plains bordering the foothills on the eastern side oi 

 the mountains, flowering in September. 



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