576 GRAMINE.E. (GRASS FAMILY.) 



53. LEPTOCHLOA. Spikes racemose, filiform. Flowering glume a wnless. 



54. DIPLACHNE. Spikes racemose. Flowering glume mucronate or awned. 



TRIBE IX. FESTUCE.33. Spikelets panicled, few - many-flowered, the flowers all per 

 feet, or the uppermost, and rarely the lowest imperfect or abortive. Glumes mem- 

 branaceous or rarely indurated, awnless, or short-awued at or near the tip. 



* Flowers perfect, or the uppermost abortive. 

 <- Flowering glumes 2-cleft and awned at the apex. 



55. TRIODIA. Spikelets few-flowered. Nerves of the glumes hairy, excurrent. 



50. TRIPLASIS. Spikelets 3-flowered. Flowering glume and palea fringed, the mid-nerve 

 of the glume extended into a bearded awn. 



57. BROMUS. Spikelets large, few - many-flowered. Flowering glume rounded on the 



back, and awned below the 2-cleft apex. 



H- H- Flowering glumes entire, awnless (except in No. 58). 

 M- Glumes obtuse or rounded on the back. 



58. FESTUCA. Spikelets mostly terete. Flowering glumes rigid, often awned at the tip. 



59. MELICA. Spikelets short and thick, few-flowered, the upper flowers imperfect, con- 



volute. Glumes 5-uerved, obtuse, scarious-margined. 



GO. GLYCERIA. Spikelets terete or flattish. Flowering glume 7-nerved, scarious at the 

 tip. 



61. DIARRHENA. Spikelets few, several-flowered. Flowering glume coriaceous, 3-nerved, 



acute. Culms nearly leafless. 



++ -H- Glumes keeled on the back. 



62. DACTYLIS. Spikelets in dense 1-sided clusters. Glumes awn-pointed, ciliate on the 



keel. 



63. EATONIA. Spikelets 1 - 3-flowered. Lower glume narrow, the upper 3-nerved, obo- 



vate, enclosing the florets. 



64. POA. Spikelets few-flowered. Flowering glume thin, 5-nerved, scarious on the mar- 



gins, commonly woody below. 



65. ERAGROSTIS. Spikelets few - many-flowered, compressed. Flowering glume 3- 



uerved, acute. Paleae persistent. 



* * Lower flowers imperfect. 



66. UNIOLA. Spikelets broad and flat. Glumes rigid, compressed, the 3-6 lower ones 



empty. 



67. PHRAGMITES. Spikelets villous, 3 - 6-flowered. Lowest flower triandrous. 



* * * Flowers dioecious. 



68. DISTICHLIS. Spikelets large, flat, many-flowered. Glumes rigid, rounded on the 



back. 



69. MONANTHOCHLOE. Spikelets single, terminal, 3 - 5-flowered. Leaves very short and 



rigid. 



TRIBE X. HORDEJE. Spikelets 1 - several-flowered, sessile on opposite sides of the 

 jointed rachis of the terminal spike. Empty glumes 1-2, rigid, rarely wanting. Up- 

 permost flowers imperfect or abortive. 



* Spikelets solitary at each joint of the rachis. 



70. LOLIUM. Spikelets placed edgewise on the rachis. Empty glume one. 



71. AGROPYRUM. Spikelets placed flatwise on the rachis. Empty glumes two. 



* * Spikelets 2 - 4 at each joint of the rachis. 



72. HORDEUM. Spikelets 3 at each joint, 1-flowered, the lateral ones sterile. 



73. ELYMUS. Spikelets 2 - 4 at each joint, 1 - several-flowered. Empty glumes 2, 



collateral. 



74. ASPRELLA. Spikelets 1 -3 at each joint. Empty glumes none. 



