9. GRAMINEAE. 37. 



52. Glumes subequal longer than floret. 34 AGROSTIS. 

 At least one of the glumes shorter than the floret. 



38 SPOROBOLUS. 



53. Reed grasses. 30 PHRAGMITES. 

 Not reed grasses. 54. 



54. Blades transversely veined. 67 ARUNDINARIA. 

 Blades not transversely veined. 55. 



55. Upper 2 or 3 valves empty, enclosing each other forming a 



club or spindle-shaped body. 56 MELICA. 



No club or spindle-shaped body. 56. 



56. Valves 3 nerved. 57. 

 Valves 5 — 11 nerved. 64. 



57. Whole panicle dense, cylindrical and usually dark purple. 

 Glumes, valves and pales equally hairy all over. 



58 STIBURUS. 

 Glumes, valves and pales not all equally hairy. 58. 



58. Valves awned or mucronate. 59. 

 Valves awnless and not mucronate. 62. 



59. Side nerves of valve excurrent into bristles. 



51 TRIRAPHIS. 

 Side nerves of valve not excurrent into bristles. 60. 



60. Spikelets distant by more than their own length. 



50 CROSSOTROPIS. 

 Spikelets not distant by more than their ov^m length. 61. 



61. Valves 2-toothed. Awn from the back. 40 DIPLACHNE. 

 Valves minutely 4-toothed. Awn terminal. 



49 LEPTOCARYDIUM. 



62. Side nerves of ^alve delicate and not submarginal. Florets 2 



or 3 with uppermost reduced. Shorter than or not much 

 longer than the glumes. 26 KOELERIA. 



Side nerves of the valve submarginal. Florets usually numer- 

 ous and far exserted from the glumes. 63. 



63. Valve entire. 41 ERAGROSTIS. 



Valve minutely notched or with 2 lateral teeth. 



40 DIPLACHNE. 



64. Spikelets deciduous as a whole. Both glumes 1 nerved. 



57 FINGERHUTHIA. 

 Spikelets breaking up, leaving glumes persistent. 65. 



65. Valves awned from the back near the middle. 



27 AVENASTRUM. 



Valves awnless or, if awned, awn terminal or subterminal. 66. 



00. Styles distinctly lateral on a hairy 2—3 lobed appendage of the 



ovary. Spikelets rather larger. 63 BROMUS. 



No hairy 2—3 lobed appendage on top of the ovary. 67. 



67. Valves 2 cleft or 2 lobed. 68. 



Valves entire or minutely bitid. 69. 



