POACEAE. 43 



Internerves of the ovate flowering glumes pubescent ; innovation several, both 

 extra- and intra-vaginal. 28. P. pseudopratensis. 



XII. Epiles. 



Flowering glumes about 5 mm. long, strongly purple-tinged, but slightly scabrous; 



stem-leaves broad. 29. P. subpurpurea. 



Flowering glumes about 4 mm. long or less, uisually greenish or slightly purple ; 



stem-leaves narrow. 30- P. epilis. 



XIII. FiLIFOLIAE. 



One species. Z^- P- nematophylla. 



XIV. Fendlerianae. 



Ligules 5-7 mm. long, acute or acuminate. 22. P. longiligula. 



Ligules short, rounded or truncate at the apex ; those of the innovations obso- 

 lete. 

 Panicle very narrow and long-peduncled, contracted. 33. P. longipedunculata. 

 Panicle more open at least in anthcsis. 



Flowering glumes narrowly oblong ; leaves very slender and rough. 



34. P. scabriuscula. 

 Flowering glumes ovate. 



Panicle very short ; plant low ; leaves smooth below, scabrous above. 



35. P. brevipatjiculata. 

 Panicle longer : plant 3-6 dm. high ; leaves scabrous below, hispid-puberu- 



lent above. 36- P. Fendleriana. 



XV. BUCKLEYANAE. 



Internerves of the flowering glumes glabrous ; nerves silky. 



Plant low ; leaves stiff, involute and often arcuate. 40- P- juncifolia. 



Plant tall ; leaves broad and flat. 37- P- glaticifolia. 



Internerves of flowering glumes more or less scabrous or strigose. 

 Flowering glumes merely scabrous throughout. 



Empty glumes strongly nerved, elongated lanceolate, almost equalling the 



oblong, very scabrous flowering glumes : leaves usually broad (2-3 mm.) 



and flat ; ligules lanceolate, acute. 38. P- nevadensis. 



Empty glumes not strongly nerved, ovate-lanceolate, usually much shorter 



than the flowering glumes, which are broader and less scabrous. 



Ligules narrowly lanceolate. 3-4 mm. long, acuminate ; stem-leaves very 



narrow and involute. 39- P- laevigata. 



Ligules short, 1-2 mm. long, triangular or broadly ovate and acutish or 

 truncate. 

 Plant 2-4 dm. high ; leaves mostly basal and stiff, short, seldom 8 cm. 



long; ligules rounded. 40. P- juncifolia. 



Plant 4-10 dm. high, leafy throughout; leaves longer. 

 Ligules ovate or rounded, acute or obtuse ; leaves soft. 



41. P. confusa. 

 Ligules very short, truncate ; leaves rather firm. 42. P. truncata. 

 Flowering glumes more or less strigose on the lower portion, scabrous above. 

 Flowering glumes not longer than the empty glumes, ovate ; pubescence much 

 longer on the nerves. 43- P- pratericola. 



Flowering glumes oblong, longer than the empty glumes ; pubescence on the 

 nerves scarcely stronger than that on the internerves. 

 Ligules ovate or rounded, obtuse or acutish. 41. P. confusa. 



Ligules lanceolate, acuminate. 



Plant yellowish green ; leaves all filiform, soft and usually involute. 



44. P. lucida. 

 Plant dark green, leaves broader, flat or condupHcate ; at least those of 

 the stem firm. 

 Creeping rootstock none ; . panicle dense ; flowering glumes greenish 

 at the base and purple above ; leaves usually narrow and con- 

 duplicate. 45- P- Bucklcyana. 



