716 GRAMINE^E 



23 Aristida Awn triple, continuous or articulated with the glume. 



24 Phleum Panicle dense and spike-like: glumes distinct: awn simple # 



25 Alopecurns Panicle spike-like : glumes more or less united at base : 

 awn simple. 



Tribe vi Avenace^e Spikelets panicled 2-several-flowered, 

 rachis often bearded, prolonged into an imperfect rudiment. 

 Glumes mostly equalling or exceeding the flower. Flowering 

 glumes usually bearing an awn on its back or between its teeth. 



* Spikelets with 2 or more lower flowers perfect. 



i6 Danthonia Spikelets several-flowered, awned from the 3 united 

 middle nerves. 



27 Avena Spikelets 2-flowered, awned from the midnerve only. 



28 Trisetum Spikelets 2-several-flowered: flowering glume 2-toothed 

 at the summit, awned from the midnerve only. 



29 Aira Spikelets 2-flowered, both perfect, the rachella not prolonged 

 beyond the upper one. 



80 Deschampsia Spikelets with 2 perfect flowers, the rachella prolonged 

 beyond the second flower. 



* * Spikelets 2-flowered with one flower staminate 



31 Arrhenatherum Lower flower staminate, upper perfect and usually 

 awnless. 



32 Holcus Lower flower perfect, awnless, upper staminate and awned. 



Tribe vii Festuce^: Spikelets panicled, 2-many-flowered, 

 the rachis usually prolonged and bearing an imperfect flower or 

 bristle. 



* Lower one or two flowers staminate or neutral. 



38 Munroa Spikelets in clusters in the axils of the upper leaves, with 

 the two lower glumes empty. 



34 Phragmites Spikelets in an ample panicle, with one staminate flow- 

 er below 2-4 perfect ones : rachis bearded with long hairs. 



* * Lowest flowers all perfect : grain not adherent to the palet. 



+■ Flowering glumes pointed, awned or acute, the nerves, when 

 present, running into the point. 



36 Dactylis Spikelets in dense one-sided clusters in a one-sided panicle : 

 glumes herbaceous, compressed, awn-pointed. 



86 Kceleria Spikelets in a dense spike-like panicle : glumes membranous, 

 keeled, pointed or mucronate. 



4- ■*- Flowering glumes pointless and, except in Melica, awnless, 

 obtuse ; the nerves parallel. , 



++ Flowering glume 1-nerved ; the palet 3-nerved. 



37 Eatonia Glumes very unlike; the upper one much broader than the 

 linear lower one and wrapped around the flower. 



** -M- One or two of the glumes 5-nerved or more. 



88 Melica Flowering glumes flattish on the back, 7-nerved or more, 

 membranaceous at tip : fertile flowers 1-3, the upper enwrapping the 



