12 MISC. PUBLICATION 243, U.S. DEPT. OF AGRICULTURE 
Glumes and lemmas awnless (fruit pointed in Scutachne). 
Lower floret of the spikelet perfect, usually fruitful; spike- 
lets small, turgid, obtuse_______ 86. ISACHNE (p. 315). 
Lower floret staminate or neuter. 
Second glume and sterile lemma leathery-indurate; fruit 
maUerona tev sire pekinese 85. ScUTACHNE (p. 313). 
Second glume and sterile lemma membranaceous; fruit 
° not mucronate. 
Inflorescence a cylindric or interrupted spikelike pani- 
cle; fruit either scarcely indurate, the palea not 
enclosed at the summit, or stipitate and the spike- 
lets with a saccate second glume; aquatics or sub- 
aquatics. 
Second glume inflated-saccate; fruit stipitate. 
83. SAccIOLEPIS (p.310 ). 
Second glume not inflated-saccate; fruit scarcely 
indurate, open at the summit, not stipitate. 
84. HyYMENACHNE (p. 312). 
Inflorescence an open or contracted panicle or, if 
somewhat spikelike, the fruit not stipitate nor the 
second glume saccate; fertile lemma chartaceous- 
indurate. 
Culms woody, bamboolike; spikelets globose, large; 
fertile lemma and palea bony-indurate, a downy 
tuft at the apexe 84: 255 82. lLastacts (p. 302). 
Culms not woody nor bamboolike. 
Fertile lemma with either lateral appendages or 
excavations at the base, the margins usually 
not inrolled_______ 81. IcHNANTHUS (p. 296). 
Fertile lemma with neither lateral appendages 
nor excavations at base, the inrolled margins 
clasping the palea____80. Panicum (p. 242). 
TRIBE 13. ANDROPOGONEAE 
Spikelets in pairs along a rachis, the usual arrangement being one 
of the pair sessile and fertile, the other pedicellate and staminate or 
neuter, rarely wanting, only the pedicel present; fertile spikelet con- 
sisting of one perfect terminal floret and, below this, a staminate or 
neuter floret, the lemmas thin or hyaline, and two awnless glumes, 
one or usually both firm or indurate. 
Spikelets all perfect. 
Inflorescence of 2 to several digitate racemes_...___116. IscHAEMuUM (p. 416). 
Inflorescence a densely flowered hairy panicle. 
Splkeletsrawmed!) pe ies shee seen eee icicoee eee ee 104. ErRIaAntuHus (p. 380). 
Spikelets awnless. 
Rachis con timuOuss <= 5 eee ee 101. ImpERata (p. 376). 
RAchis: Gis] ola Giin gee oe eee shes gee 102. SaccHarvum (p. 379). 
Spikelets not all perfect, the sessile usually perfect, the pedicellate usually stami- 
nate or rudimentary (pistillate in Eriochrysis). 
Fertile spikelet with hairy-pointed callus formed of the attached supporting 
rachis joint or pedicel or of the upper part of the peduncle; awns usually 
long. 
Racemes reduced to a single joint, long-peduncled in a simple open panicle 
113. RuHapuis (p. 410). 
Racemes of few or many joints, not in an open panicle. 
Rachis continuous; perfect spikelets pedicellate, disarticulating at the 
base of the pedicel; awns plumose_115. TRAcHYPOGON). (p. 415). 
Rachis disarticulating, the joints attached to perfect spikelets next above, 
forming a callus to them. 
Racemes solitary, not subtended by leaflike spathes; perfect spikelets 
several to many above; staminate spikelets several to many 
below SW 2422 ee eae 114. HETEROPOGON (p. 412). 
Racemes several in a flabellate cluster, subtended by leaflike spathes; 
perfect spikelet 1 in each raceme--__-_-_- 120. THEMEDA (p. 420). 
