GRAMINE^E. 47 



Spikes rarely solitary ; spikelets 2-nate, 2-fld., 

 awned. 33. Ischce.mum. 



Spikes solitary, spikelets 1-fld., gl. I pectinate. 



34. Eremochloa. 



** Margins of gl. I of sessile spikelets not inflexed. 

 Spikes solitary ; spikelets 2-nate, 1-2-fld., 2-awned. 



35. Pogonatherum. 

 Spikes digitate ; spikelets 1-fld., 



36. Arthraxon. 



Subtrlbe V. Apludece. Spikelets 3 on an inarticulate 

 rachis. 37. Apluda. 



Subtribe VI. Itottboelliece. Spikelets homo- or hetero-gamous, 

 1-2-fld., solitary, or 2- rarely 3-nate on the internodes 

 of an articulate spike or raceme, not awned., gl. I 

 not keeled, adnate to or sunk in a depression formed 

 by the internode and pedicel of the upper spikelets ; 

 gls. of sessile spikelet 4. 



Spikelets 2-nate, gl. I flat. 38. Eoitboellla. 



Spikelets 2-nate, gl. I globose. 39. Manisuris. 



Spikelets solitary, gl. I convex. 40. Ophiurus. 



Subtribe VII. Euandropogonece. Spikelets heterogamous 



1-fld., 2- rarely 3-nate on the whorled articulate 



branches of simple or compound racemes or panicles, 



gls 4, I not keeled, IV usually awned. 



Sessile spikelets of all the pairs alike in sex and 

 form throughout the spikes. 



Joints of rhachis and pedicels of upper spikelets 

 linear, compressed, with usually a central trans- 

 lucent channel and thickened margins. 



41. Andropogon. 



Joints of rachis very few, filiform, opaque ; 

 lodiceles ciliate ; grain dorsally compressed. 



42. Sorghum. 



