10 MISC. PUBLICATION 243, U.S. DEPT. OF AGRICULTURE 
TRIBE 10. ZIZANIEAE 
Spikelets unisexual, the pistillate terete or nearly so; glumes 
shorter than the lemma, usually one or both obsolete, the pedicel 
disarticulating below the spikelet. Glumes well developed in 
Pharus, placed in this tribe provisionally. 
Pistillate spikelet subglobose; glumes wanting; blades narrowly linear. 
62. Luztoua (p. 149). 
Pistillate spikelet cylindric, beaked; glumes present; blades broad, elliptie or 
oblanceolate-oblonig 24-1322) Shi Wh ern rebar o 63. PuHarvus (p. 151). 
TRIBE 11. MELINIDEAE 
Spikelets disarticulating below the glumes, these very unequal, 
the first minute, the second and the sterile lemma equal, mem- 
branaceous, strongly nerved, the latter bearing a slender awn from 
the notched summit; fertile lemma and palea thinner in texture, 
awnless. 
Awn (of lemma) bentior twisted =. _ Satie Dae es 64. ARUNDINELLA (p. 155). 
Awns straight. 
Glumes awned; lemma awnless. 
Spikelets with a long pointed callus below__----_-- 65. ACHLAENA (p. 157). 
Spikelets without a callus below_______--_------ 66. REYNAUDIA (p. 159). 
Glumes awnless; sterile lemma awned_______.__------ 67. Me tiInis (p. 160). 
TRIBE 12. PANICEAE 
Spikelets with one perfect terminal floret, and below this a sterile 
floret and two glumes; fertile lemma and palea indurate or at least 
firmer than the glumes and sterile lemma, a lunate line of thinner 
texture at the back just above the base, the rootlet protruding 
through this at germination; articulation below the spikelet. 
Spikelets unisexual; plants monoecious. 
Inflorescence of 2 digitate spikelike racemes, one pistillate, the other stami- 
nate. 
KRertilestioretyobuulse 2e= 228 255 ake een eee 99. MNiIocHLoa (p. 374). 
Fertile floret narrowed into a slender awn___-100. EKMANOCHLOA (p. 374). 
Inflorescence paniculate, the panicle often much reduced. 
Panicles large, terminal on the culms or leafy branches, the pistillate spike- 
lets above, the staminate below in the same panicle. 
96. OxyRa (p. 366). 
Panicles all axillary or axillary and termina], the terminal when present 
wholly staminate. 
Fruit laterally compressed, conspicuously gibbous on the upper dorsum. 
LITHACHNE (p. 368). 
Fruit dorsally compressed, lanceolate__----------- 98. Rappta (p. 372). 
Spikelets perfect. 
Axis thickened and corky, the spikelets sunken in cavities in its joints, these 
disarticulating at maturiby= = —- 2s ee 72. STENOTAPHRUM (p. 177). 
Axis not thickened, the spikelets not sunken in it. 
Spikelets subtended (only the terminal one in some species of Setaria) or 
surrounded by 1 to many bristles or spines (sterile branchlets), these 
distinct or more or less connate at base, forming a false involucre. 
Bristles persistent. 
Sterile palea at maturity becoming cartilaginous and winged, much 
exceeding the spikelet in width; spikelets secund along the branches 
of a simple panicle, each subtended by a single viscid bristle. 
92. IxopuHorRus (p. 352). 
Sterile palea not enlarged at maturity__________ 91. SErarta (p. 332). 
Bristles falling with the spikelets at maturity. 
Bristles solitary, much exceeding the appressed spikelet. 
9 PARATHERIA (p. 352). 
