58(57). Lemmas as broad as long, the margins outspread; florets closely imbri- 

 cate, horizontally spreading 7. Briza 



58. Lemmas longer than broad, the margins clasping the palea; florets not hori- 



zontally spreading (59) 



59(58). Lemmas keeled on the back (60) 



59. Lemmas rounded on the back (slightly keeled toward the summit in Festuca 



and Bromus) (62) 



60(59). Spikelets strongly compressed, crowded in 1 -sided clusters at the ends 

 of the stifif naked panicle branches 12. Diictylis 



60. Spikelets not strongly compressed, not crowded in 1 -sided clusters (61) 



61(60). Lemmas awned from a minutely bifid apex; spikelets large 2. Bromus 



61. Lemmas awnless; spikelets small 6. Poa 



62(59). Nerves of lemma parallel, not converging at summit or but slightly so 

 (63) 



62. Nerves of lemma converging toward the summit, the lemmas narrowed at 



apex (64) 



63(62). Nerves prominent; plants usually rather tall, growing in fresh-water 

 marshes or wet woodlands 5. Glyceria 



63. Nerves faint; plants low, usually growing in saline soils 4. Puccinellia 



64(62). Lemmas awned or awn-tipped from a minutely bifid apex; palea ad- 

 hering to the caryopsis 2. Bromus 



64. Lemmas entire, pointed, awnless or awned from the tip (65) 



65(64). Spikelets awned (awnless in a few perennial species); lemmas pointed.... 

 3. Festuca 



65. Spikelets awnless 6. Poa 



1. Anindinaria Michx. 



About 150 species in warmer parts of the world; one species in our area. 



1. Anindinaria gigantea (Walt.) Muhl. Giant cane. Fig. 77. 



Mostly glabrous robust rhizomatous cane-grass forming dense brakes; primary 

 aerial culms perennial (not usually freezing back), 2-8 m. tall, 2-20 mm. thick, 

 erect, with some ascending or appressed branches along the length; sheath margins 

 ciliate; small sheath auricles usually with a few spreading bristles; blades very 

 shortly petiolate, of two size-classes, larger ones on the primary aerial culms 

 12-20 cm. long and 10-25 mm. broad, smaller ones on the branches; inflores- 

 cences narrowly paniculate, the lower pedicels mostly included in the sheath and 

 the upper ones free (most of them nearly as long as their spikelets); spikelets 

 few, 5-8 cm. long, about 8 mm. broad, 9- to 1 3-flowered, lax enough so that the 

 internodes of rachis are often visible; zone of abscission at lower part of each 

 lemma node; lower lemmas 22-25 mm. long, cymbiform, finely pubescent, 

 obscurely 1 1 -nerved, with fine awnlike tips. 



Locally forming brakes in low areas near sloughs, bayous and rivers, in s.e. 

 Okla. {Waterfall) and in e. and s.e. Tex., s.w. to Wharton Co., spring; s.e. U. S,, 

 n. to N. C, O. and Ind. 



Giant cane formerly covered many square miles in east and southeast Texas 

 but with the introduction of domestic stock it has almost disappeared and is 

 now relatively rare. 



2. Bromus L. Chess. Brome 



Plant diverse in habit; inflorescense an open or dense panicle; spikelets diverse, 

 large, either strongly compressed or turgid, several-flowered with all the flowers 



175 



