HITCHCOCK AND CHASE — NORTH AMERICAN PANICUM. 229 



DESCRIPTION. 



Vernal form tufted, yellowish green; culms slender, 15 to 40 cm. high, rarely- 

 higher, spreading, the lower internodes usually short, as in P. subvillosum, producing 

 a leafy base as in that species, sparsely papillose-pubescent, the upper more or less 

 elongated, glabrate, the nodes pubescent; sheaths rather sparsely papillose-pubescent, 



rarely almost glabrous; ligules 3 to 4 mm. long; blades 

 firm, erect or ascending, 4 to 8 cm. long, 5 to 7 mm. 

 wide, acuminate, rounded at, the base, the upper 

 surface with a few long hairs toward the base and 

 margin, otherwise glabrous, the under surface ap- 

 pressed-pubescent; panicles long-exserted, 4 to 7 

 cm. long, about two-thirds as wide, rather loosely 

 flowered, the flexuous branches ascending or spread- 

 ing; spikelets 1.8 mm. long, 1 mm. wide, elliptic- 

 obovate, subacute, pubescent; firstglume one-fourth 

 the length of the spikelet or less, obtuse or pointed; second glume and sterile 

 lemma as long as the fruit at maturity; fruit 1.6 mm. long, 0.9 mm. wide, elliptic, 

 subacute. 



Autumnal form branching from the lower nodes, forming a spreading bunch or 

 tussock 10 to 15 cm. high; leaves and panicles reduced; winter rosette appearing 

 late, the blades narrowly lanceolate, glabrous or pilose at base. 

 This species is less pubescent than any other in this group. 



Fig. 239.— P. occidentale. From type 

 specimen at Prague. • 



DISTRIBUTION. 



Peat bogs and moist sandy ground, British Columbia and Idaho to southern California. 



Idaho : Lake Coeur d' Alene, Sand- 

 berg, Heller & MacDougal in 

 1892; Priest Lake, Piper 3778. 



Washington: Montesano, Heller 

 3978; Chelan County, Whited 

 in 1901; Lake Chelan, Elmer 

 489, Lake & Hull 118; Bingen, 

 Suhsdorf 5162, 5174; Granville, 

 Conard 378, Yakima County, 

 Cotton 736, 792. 



British Columbia : Lake Osoyoos, 

 Macoun 77229; Vancouver Is- 

 land, Canby 352 (Gray Herb.). 



Oregon: Mount Scott, Sheldon in 1902; Columbia River, Sheldon 8706. 



California: Crescent City, Davy 5971; Mendocino, Davy 6092, McMurphy, 425; 

 New York Falls, Hansen 1723; Yosemite Valley, Brewer 1646; Merced River, 

 Torrey 587; San Diego, Orcutt 540; without locality, Bridges 366, Hartiveg 2024. 



Fig. 240.— Distribution of P. occidentale. 



134. Panicum pacificum sp. no v. 



DESCRIPTION. 



Vernal form light green; culms tufted, 25 to 50 cm. high, ascending or spreading, 

 leafy (culm leaves 5 or 6), papillose-pilose with spreading hairs, the nodes shortly 

 spreading-pilose; sheaths papillose-pilose, the papillae prominent; ligules 3 to 4 mm. 

 long; blades erect or ascending 5 to 10 cm. long, 5 to 8 mm. wide, acuminate, nar- 

 rowed toward the rounded base, the upper surface papillose-pilose, typically with 

 short hairs intermixed, but these often wanting and the long hairs sometimes sparse, 



