POACEAE. 



Spikelets 1-flowered. 

 Spikelets 2-many-llo\vere(J. 

 Spikelets in two rows. 



Tribe IV. 



Tribe VI. 



Tribe V. 



thickened ring-like 



Tribe I. MAYDEAE. 



Fertile spikelets imbedded in the internodes of the thick 

 rachis. 



Tribe II. ANDROPOGONEAE. 



Internodes of the rachis not thickened nor excavated for 

 the reception of the spikelets. 

 Spikelets alike, perfect. . 



Axis of the racemes continuous, not articulated. 

 Axis of the racemes articulated. 

 Spikelets not alike. . ^ 



Sessile spikelets alike throughout the inflorescence. 

 Racemes singly disposed : apex of the rachis-inter- 

 nodes a translucent cup-shaped, entire or irreg- 

 ularly toothed, appendage. 

 Racemes disposed in pairs or more : apex of the 

 rachis-internodes not appendaged. 

 Some or all of the racemes sessile. 

 All of the racemes more or less pedunculate. 

 Lower spikelets differing from the others. 

 Internodes of the rachis much thickened, and excavated 

 to receive the spikelets. 

 First scale of the spikelet flat or convex. 

 First scale of the spikelet globose. 



Tribe III. PAXICEAE. 



Spikelets not sunken in the rachis. 

 Spikelets naked, not involucrate. 

 Empty scales 2. 



Lower empty scale with 



callus. 

 Lower empty scale unappendaged. 



Spikelets ovate to orbicular, usually obtuse, 



rarely acute. 

 Spikelets lanceolate, acute or acuminate. 

 Empty scales 3. . 



Empty scales awned or awn-pointed. 



Stems erect: leaf-blades long and narrow: 



racemes usually of many spikelets. 

 Stems creeping : leaf-blades short and broad : 

 racemes or clusters usually of few spikelets. 

 Empty scales not awned. 



Second scale not saccate at the base. 



Stems and branches not woody nor bamboo- 

 like. 

 Fruiting scale rigid, the margins 

 inrolled. 

 Palet of the third scale not enlarged. 

 Palet of the third scale enlarged, 

 forcing the spikelet open. 

 Fruiting scale not rigid, the hyaline 

 margins not inrolled. 

 Spikelets long-silky: fruiting-scale 



lanceolate-acuminate. 

 Spikelets glabrous or short-pubes- 

 cent : fruiting scale elliptic. 

 Stems and branches woody, bamboo-like, 

 outer scales papery, woolly-tipped. 

 Second scale saccate at the base. 

 Spikelets involucrate. 



Involucre of numerous bristles. 



Bristles persistent : spikelets deciduous. 

 Bristles deciduous with the spikelets. 

 Involucre of 2 spine-l)earing valves. 

 Spikelets sunken in one side of the flat rachis. 



Tribe IV. AGROSTIDEAE. 



r'lowering scale indurated when mature and very closely 



embracing the grain, or at least hrmer than the 

 empty scales. 

 Flowering scale Pawned. 



AGROSTIDEAE 



FESTl'CEAE. 



CHLORIDEAE. 



t. Tripsacum. 



2. Imperata. 

 :}. erianthus. 



4. SCHIZACHTEIUM. 



5. Andropogon. 

 (5. Cheysopogon. 

 7. Heteropogon. 



8. Coelorachis. 



9. Hackelochloa. 



11. Eriochloa. 



10. Paspalum. 

 12. Syntherisma. 



13. Echixochloa. 



14. Oplisjienus. 



1,5. Panicum. 

 16. Steinchism.^. 



11a. Valota. 

 12. Syntherisma. 



17. Lasiacis. 



18. Sacciolepis. 



19. ClIAETOCHLOA. 



20. Cenchropsis. 



21. Cenciieds. 



22. Ste.notaphelm. 



