POACEAE. 



Spikelets in panicles or panicled ra- 

 cemes, the latter not whorled, com- 

 monly distant. 

 Stems and branclies woody, bamboo-like, outer 

 scales papery, woolly-tipped. 

 Spikelets involucrate. 



Involucre of numerous bristles. 



Bristles persistent : spikelets deciduous. 

 Bristles deciduous with the spikelets. 

 Involucre of 2 spine-bearing valves. 

 Spikelets sunken in one side of the flat rachis. 



Tribe IV. ORYZEAE. 



Spikelets perfect : empty scales wanting or present as 

 rudiments. 



Tribe V. AGROSTIDEAB. 



Flowering scale indurate when mature and very closely 

 embracing the grain, or at least firmer than the empty 

 scales. 

 Flowering scale 3-awned. 

 Flowering scale 1-awned. 

 Flowering scale usually hyaline or membranous at ma- 

 turity, at least more delicate than the empty ones : grain 

 loosely enclosed. 



Tribe VI. AVENEAE. 



Flowers perfect : spikelets drooping : grain furrowed, adher- 

 ing to the scale. 



8. Valota. 

 12. Lasiacis. 



13. Chaetochloa. 



14. Cenchropsis. 



15. .Cbnchrus. 



16. Stenotaphrum. 



17. HOMALOCENCHRCS. 



18. Aristida. 



19. muhlenbergia. 



20. Sporobolus. 



21. A^-EXA. 



Tribe VII. CHLORIDEAE. 



Spikelets deciduous as a whole. 

 Spikelets with at least the empty scales persistent. 

 Spikelets with one perfect flower. 



No scales above the flowering scale. 

 One-several scales above the flower. 



Second empty scale acute : awn of flowering scales 



usually long. 

 Second empty scale truncate or 2-toothed : flow- 

 ering scales awnless or awn-pointed. 

 • Spikelets with 2 or 3 perfect flowers. 



Spikes commonly digitate : spikelets crowded. 

 Spikes with terminal spikelets. 

 Spikes with the rachis extending beyond the 

 spikelets in a manifest point. 

 Spikes distant : spikelets alternate. 



22. Spartina. 



23. Capriola. 



24. Chloris. 



25. eustachys. 



26. Eleusine. 



27. Dactyloctenium. 



28. Leptochloa. 



Tribe VIII. FESTUCEAE. 



Hairs on the rachilla or flowering scale very long, and en- 

 closing the latter : tall reed-like grasses. 

 Hairs on the rachilla or flowering scales shorter than the 

 scale : lower grasses not reed-like. 

 Flowering scales 1-3-nerved. 



Stigmas barbellate : styles elongate. 

 Stigmas plumose : styles short or wanting. 



Lateral nerves of the flowering scale pilose. 



Inflorescence simple or compound, contracted 

 or open, the spikelets on pedicels of vary- 

 ing length. 

 Inflorescence composed of long branches along 

 which the appressed spikelets are arranged 

 on short pedicels, or sometimes only a 

 1-sided raceme. 

 Lateral nerves of the flowering scale glabrous. 

 Flowering scales 5-nerved. 

 Empty basal scales 3-6. 

 Empty basal scales 2. 



29. Phragmites. 



30. MONANTHOCHLOE. 



31. Tridexs. 



32. 

 33. 



34. 

 35. 



DiPLACHNE. 



Eracrostis. 

 Uniola. 



DiSTICHLIS. 



1. TMPSACUM L. Erect monoecious plants with stout rootstocks. 

 Spikes articulate, elongate. Staminate spikelets 2-flowered, in pairs. Pistillate 

 spikelets l-flowered, in excavations in the rachis, the scales thick and shining. 



