ANDROPOGONE/E I39 



Margins of the first glume of the sessile spikelet infiexed. 

 Spikes rarely solitary ; spikelets binate, 

 2-flowered and awned ... ... ... 20. Ischaemum. 



Spikes solitary ; spikelets l-flowered ; first 



glume of the sessile spikelet pectinate ... 21. Eremochloa. 

 Margins of the first glume of the sessile spikelet not infiexed. 

 Spikes solitary or binate ; spikelets 1- to 

 2-flowered, diandrous; first glume broad 



and truncate ... ... 22. Apocopis. 



Spikes 2 or more ; spikelets binate, upper 



alone awned ... 23. Lophopogon. 



Sub. Tribe 4. Apludeae. 



Spikelets three on an inarticulate rachis ... 24. Apluda. 



Sub. Tribe 5. Rottboellieas. 



Spikelets similar or dissimilar, I- to 2-flowered, solitary, 2- 

 or rarely 3-nate on the internodes of an articulated spike or 

 raceme, not awned ; the first glume is not keeled, sunk in a cavity 

 of joints of the rachis ; sessile spikelets 4-glumed. 



Sessile spikelets single ; first glume flat ••• 25. Rottboellia. 

 Sessile spikelets geminate in all except 



the uppermost joints 26. Mnesithea. 



Sessile spikelets binate ; first glume glo- 

 bose, pitted 27. Manisuris. 



Sub. Tribe 6. Eu-Andropogonea2. 



Spikelets are dissimilar, l-flowered, 2- (rarely) 3-nate on the 

 whorted articulate branches of simple or compound racemes or 

 panicles ; glumes four, first glume not keeled, fourth glume usually 

 awned. 



Spikelets binate below and 3-nate at 

 the top on a spicate or panicled inflores- 

 cence ... ... ... 28. Andropogon. 



Spikelets in two superposed series. Upper series ofoneormore 

 sessile bisexual or female spikelets with one terminal pedicelled 

 male spikelet. 



Rachis jointed above the involucral spike- 

 lets ... ... ... ... 29. Anthistiria. 



Rachis jointed below the involucral spike- 

 lets ... ... ... 30. Iseilema. 



