90 



Kansas Academy of Science. 



Flowering glumes broadly ovate, rigidly coriaceous, the 3 nerves prominent 



and uniting to form a pointed tip, stamens 2 44 Biarrhena. 



Flowering glumes not as above, either cuspidate, or 3-toothed or erose; 



«tamens 3 37 Triodia. 



Spikelets narrow, sessile or nearly so, more or less distant on the long 



branches of the panicle, usually in 2 rows 39 Diplachne. 



Spikelets 3-5-flowered, numerous in a dense spike-like cylindrical or inter- 

 rupted panicle 42 Koeleria. 



Spikelets pedicillate or sessile, but not as above (51). 



Spikelets usually many-flowered, palet shorter than the glume, often per- 

 sisting after the grain and glume have fallen away 40 Eragrostis. 



Spikelets ovate, 3-5-flowered; palet longer than its glume, of nearly the 

 same texture, bidentate, folded lengthwise in the middle and with the 

 two keels folded in the opposite direction 38 Redfieldia. 



Culm with a single, uniform, cylindrical (or oval) spike or spike-like pan- 

 icle (53). 

 Not as above (58). 



Bristles below the spikelets (54). 

 No bristles present (55). 



One or sometimes 2 small scales or bristles below the flower, spike ovoid 10 Phalaris. 



Conspicuous bristles below the spikelets, spike cylindrical 6 Setaria. 



Flowering glume terminating in a trifid awn, or apparently 3-awned .12 Aristida. 



Awns absent or not trifid (56). 



Outer glumes long-awned from the apex 20 Polypogon. 



Outer glumes acute (57). 



Glumes 4, none of them awned 10 Phalaris. 



Glumes 6, second pair awned on the back 11 Anthoxanthum. 



Outer glumes hairy, a peculiar cup-like or annular swelling of the pedicel 



just below the spikelet 4 Eriochloa. 



Not as above (59). 



Swamp grasses, 7 to 12 feet tall, leaves very broad and long, panicle large 



terminal 36 Phragmites. 



Not as above (60). 



Awns trifid, or apparently 3 awns 12 Aristida. 



Awns absent or not trifid (61). 



Glumes (including palet) only 2; flowers monoecious 8 Zizania. 



Glumes (including palet) 6, second pair awned on the back 11 Anthoxanthum, 



Glumes (including palet), the normal number (62). 



Flowering glume coriaceous, rigid, involute with a simple twisted awn from 



the apex 13 Stipa. 



Flowering glume not as above (63). 



Spikelets solitary at each joint of the slender triangular rachis of the pan- 

 iculate spikes, and partly immersed in an excavation 30 Schedonnardus. 



Spikelets not as above (64). 



Flowering glume hardened, often with a sharp-pointed and bearded pedicel 



at the base, awn twisted 13 Stipa. 



Flowering glume awned, but not as above (65). 

 Flowering glume not awned (73). 



Spikelets sessile and remotely alternate, on long and filiform branches of 

 the panicle, each with one, or rarely 2 perfect flowers, and with a bristle- 

 like rudiment or an awn-like pedicel 29 Gymnopogon. 



Not as above (66). 



Palet ciliate on the apex and keels, lateral nerves of the outer glumes van- 

 ishing within the scarious margin 43 Melica. 



Palet rigid, broad, stamens 2, grain very large, larger than the flower; 



flowering glume pointed, but not really awned 44 Diaurhena. 



Palet only one-nerved, stamen one, flowering glume awned near the apex. ..21 Cinna. 



Palet not as above (67). 



