534 Rydberg : Rocky Mountain flora 



Poa scaberrima sp. nov. 



A tufted perennial, with numerous intravaginal innovations ; 

 stem 3-5 dm. high, 2- or 3-leaved, glabrous ; ligules lanceolate, 

 acuminate ; leaf-blades filiform, involute, very scabrous, pale green ; 

 blades of the basal leaves 8-15 cm. long, less than 1 mm. wide; 

 those of the stem-leaves 1—5 cm. long, erect ; panicle elliptic, 

 dense, 4—7 cm. long ; branches short, strongly ascending ; spike- 

 lets about 1 cm. long ; empty glumes ovate, nearly equal, 4-5 

 mm. long, glabrous ; floral glumes ovate, acuminate, pale, slightly 

 tinged with purple, 5-6 mm. long, strongly 5-nerved, and con- 

 spicuously scabrous. 



The type was named by Professor Scribner Poa Cusickii, from 

 which it differs, however, in the larger, paler, very scabrous, acumi- 

 nate floral glumes and the pale scabrous filiform leaves. In habit 

 it more resembles P. idahoensis and P. subaristata. From the 

 former it differs in the dense inflorescence and broader glumes ; 

 from the latter in the broader glumes and the lanceolate ligules. 



Idaho : Beaver Canon, June 27, 1895, Rydberg 2033 (type, in 

 herb. N. Y. Bot. Gard.). 



Poa Helleri sp. nov. 



A tufted perennial ; stem slender, 4-6 dm. high, often purple- 

 tinged below ; ligules lanceolate, acuminate ; leaf-blades very slen- 

 der, flaccid, 5—15 cm. long, 1 mm. wide, more or less involute, 

 scabrous; panicle rather loose, 8—10 cm. long; branches ascending; 

 spikelets about 1 cm. long, 4- or 5-flowered ; empty glumes linear- 

 lanceolate, 3 -nerved, glabrous, unequal, 4-5 mm. long ; floral 

 glumes linear-lanceolate, about 5 mm. long, strigulose below, sca- 

 brous on the upper part. 



The type was named Poa Sandbergii y but it can scarcely be 

 referred to that species. It differs in the pale inflorescence, larger 

 and much narrower, conspicuously strigose floral glumes. In 

 habit it resembles P. idahoensis, but evidently belongs to the same 

 group as P. nevadensis, from which it differs in the slender habit 

 and the narrower glumes with a different pubescence. 



Idaho : Lake Waha, A. A. & E. Gertrude Heller 3 2 J 4. (type, 

 in herb. Columbia Univ.). 



Poa curta sp. nov. 



Perennial, with a horizontal rootstock ; stem glabrous, 4-5 dm. 

 high ; sheaths short, glabrous ; ligules about I mm. long, truncate ; 



