224 POACE.E. 



with a very short blunt callus. Enipty glumes 2, persistent, equal 

 or the outer a little shorter, convex on the back, floral glume broad, 

 shorter or longer than the other glumes, membranous, becoming 

 hard, obtuse, truncate, usually producing a caducous awn, which is 

 more or less bent near the base; palea 2-keeled. Stamens 3. Lodi- 

 cules 3, conspicuous. Styles short or long, distinct. Grain oblong 

 or ovate, enclosed by the hardened floral glume and palea, but not 

 adherent. 



Tufted perennial grasses ; leaf-blades broad and flat or narrow 

 and involute. Panicle terminal, lax. 



There are about "Zi species, mostly found in the temperate and 

 subtropical regions of the northern hemisphere. The genus diil'ers 

 from Sfipa in having a shorter awn, but little twisted or tortuose, 

 a broader floret, the callus siiorter and broader and obtuse. It is. 

 certainly very convenient, so far as our species are concerned, to 

 leave Eriocoma as a genus; then Oryzoi^sis can be more clearly 

 defined and separated from Stipa. 



IJentham observes that it is nearly allied to Milimn. Tlie 

 genus divides readily into three sections, regarded by some as dis- 

 tinct genera, but Triuius and Beutham and others agree in uniting 

 them. 



1. Piptatherum (Beauv., as a genus), often included in NiJnini, 

 with awned glumes. The obliquity of the fruiting glume is much 

 less marked tlian in the typical species of Ori/zopsin: 



2. Enort/zopsis includes CarijorhJoa Spreng., Pipfnchclinm 

 Presl and Nusmlla Desv., iXvd rachilla bearing a ring of hairs under 

 tlie floral glume. 



:5. Eriocoma Nutt., Eendleria (Stcud.), difi'ers from Eiioryzopsis 

 in the long silky hairs clothing the fruiting glumes. 



A. Leaf- blades broad, flat, no rudimentary blades, ligule cil- 

 iate I 



B. Leaf-blades long, involute, petiolate, evergreen, upper 



blades midimentary 2, 3 



0. Leaf-blades very narrow, involute (a) 



a. Floret clothed with dense white conspicuous hairs, 

 panicle open, rays diverging, awn 2 cm. long. ... 4 



