GRAMINEJE. (GRASS FAMILY.) 547 



■I- •»- Lower palea entire, awnless or (in No 33) awn-pointed. 

 H-i- Glumes unlike, the lower one linear, the upper ohovate. 



26. EATONIA. Spikelets 1-5-flowered. Culms slender, tufted. 



■H- ++ Glumes alike. Lower palea rounded on the back, not keeled. 



27. MELICA. Spikelets 3 - 5-flowered. Lower palea many-nerved. 



28. GLYCEllTA. Spikelets 5 - many-flowered. Lower palea strongly V-nerved. 



29. ARTJNDINAIIIA. Spikelets loosely many-flowered. Culms woody. 



30. iiitiZOPYliUM. Spikelets dioecious. Lower palea rigid. 



++ -H- ++ Glumes alike. Lower palea keeled. 

 81. POA. Paleae falling away together, the lower one 6-nerved, and with cobwebby hairs at 

 the base. Spikelets 3 - 6-flowered. 



32. ERAGROSTIS. Lower palea fallicig before the upper one, 3-nerved, not hairy. 



33. DACTYLIS. Lower palea awn-pointed. Panicle contracted, composed of 1-sided clusters. 



* * Grain adherent to the upperpalea, downy at the apex. 



34. FESTUCA, Lower palea entire, acute or awn-pointed. 



35. BROMUS. Lower palea 2cleft, awned between the teeth. 



* * * Grain free, smooth. Lowest flowers of the apikelet imperfect. 



36. UNIOLA. Spikelets broad and flat, many-flowered. Palesfe coriaceous. 



37. PHRAGMITES. Spikelets 3 - 6-flowered, silky bearded on the rachis. Palese thin. 



Teibe "V. HORDEACE^, — Spikelets 2 -several-flowered, sessile, on opposite sides of 

 the jointed rachis, spiked. Glumes 1-2, rarely wanting. Palese 2. 



38. ELYMUS. Spikelets 2 - 4 at each joint of the rachis. Glumes 2, placed side by side before 



the spikelets. 



39. GYMNOSTICIIUM. Spikelets 2 -3 at each joint of the rachis. Glumes none, 



40. LOLIUM, Spikelet solitary at each joint of the rachis. Glume 1. 



Tribe VI. AVEIX ACEJE. — Spikelets panicled, 2 - several-flowered, the terminal flow- 

 ers mostly imperfect. Kachis or base of the flowers often bearded. Lower palea with a 

 twisted, bent, or straight awn on the back, or below the apex 



41. AIRA. Spikelets 2-flowered. Lower palea thin, r iunded on the back, awned below the 



middle. 



42. TlilSETCM. Spikelets 2 - several-flowered. Lower .palea thin, compressed-keeled, bear- 



ing a bent awn below the 2-cleft apex. 



43. DANTIIONIA. Spikelets 2 -several-flowered. Lower palea rigid, many -nerved, bearing 



a flattened and twisted awn at the 2-cleft apex. 



44. ARIIHENATHERUM. Spikelets 2-flowered, the lower flower staminate, and bearing a 



long bent awn below the middle. 



Tribe VII. PIIALARIDE.^. — Spikelets in spike-like panicles 3-flowered, the upper 

 or middle flower perfect, the two lateral ones imperfect or mere rudiments. Glumes 2. 

 Palese 2, indurated in fruit. 



45. ANTHOXANTHUM. Lateral flowers neutral, each of one awned palea. Perfect flower 



diandrous. 

 46- PHALAIllS. Lateral flowers rudimentary. Perfect flower triandrous. 



Tribe VIII. PAWICE.^. — Spikelets 2-flowered. Glumes 2, or the lower wanting. 

 Lower flower imperfect, either staminate or neutral, with the lower palea membrana- 

 ceous and similar to the upper glume, the upper one mostly wanting. Paleae of the 

 perfect flower coriaceous. Grain mostly grooved or flattened on the outside. Flowers 

 in spikes or panicles. 

 * Lower glume and upper palea of the sterile flower wanting (tlie spikelet appearing like a 



single flower, with 2 glumes and 2 paleae)- 

 47. PASPAfiUM. Spikelets alike, plano-convex, in l-sided spikes; 



