GRAMINACEAE (GRASS FAMILY) 37 



CC. Glumes none; spikelets much laterally flattened, i -flowered. 



ORYZEAE (p. 38) 

 BB. Spikelets i- to many-flowered, more or less laterally flattish; imperfect flower 



uppermost (except HieroMoe) in spikelets of 2 or more flowers. 

 E. Spikelets not in rows. 



F. Spikelets i -flowered, in racemes or spikes or panicles. 

 G. Spikelets with 2 sterile lemmas just above the glumes. 



PHALAREAE (p. 38) 

 GG. Spikelets without sterile lemmas just above the glumes. 



AGROSTEAE (p. 38) 



FF. Spikelets 2- to many-flowered, in racemes or panicles. 

 H. Glumes usually longer than the first flower; i or more of the lemmas 

 awned on the back or between the teeth of the bifid apex. AVENEAE (p. 41) 

 HH. Glumes shorter than the first flower; lemma either awnless, or with i to 

 several terminal straight or merely divergent awns. FESTUCEAE (p. 43) 

 EE. Spikelets in 2 rows. 



I. Spikelet-rows on same side of rachis, forming i-sided spikes. 



CHLORIDEAE (p. 46) 



II. Spikelet-rows on opposite sides of rachis, forming balanced spikes. 



HORDEAE (p. 47) 



MAYDEAE (Corn Tribe). Stem solid. Spikelets unisexual. Stami- 

 nate and pistillate flowers separate on the same plant. Lemma and palet 

 thinner than the glumes. W. E. (L. zea = spelt.) We have only 

 the following. Zea mays (COMMON FIELD-CORN) 



ANDROPOGONEAE (Sugar-cane Tribe). Spikelets 1-3 at each joint 

 of the rachis, sessile or short-pedicelled, usually 3-flowered. Glumes 2, 

 thicker than the lemmas. Lemma often hyaline, often awned, the lower 

 often empty and glumelike. Palet usually shorter than its lemma, some- 

 times none. Stamens 1-3. Stigma plumose. Grain unfurrowed, free. 

 Here belongs also Saccharum officinarum (Sugar Cane). 



A. Spikelets in a spikelike panicle, in 2 's, all fertile; lemma awnless; stamens 1-2. E. 



Imperata hookeri (WESTERN BLADE GRASS) 



AA. Spikelets in a loose, somewhat spreading panicle, in 3's, lateral 2 sterile, central i 

 fertile; lemma awned; stamens 3. SORGHUM (p. 37) 



SORGHUM 



Plant 0-30 dm. high. Leaves long, wide, flat. Spikelets in a large 



terminal panicle, in pairs at its nodes or in 3's at the ends of its branches, 

 i sessile and perfect at each node. Glumes shining. Lemma hyaline, 



awned. Palet hyaline or none. Stamens 3. W. (Sorghi = the name 

 in India.) 



A. Cornlike, annual. E. Cultivated for molasses. S. vulgare (SORGHUM) 



AA. Grasslike, perennial. W. A hay grass. S. halapense (JOHNSON GRASS) 



