THE FLORA OF THE NOETHEBN TEEBITORY. 23 



Spikes of few spikelets enclosed at the base in sheathing bracts. — 22. 

 Xerochloa. 



Series II. Spikelets unisexual. Stems prostrate or divaricate. 



Spikelets monoecious in a simple spike, the upper ones male, the lower 

 female. — 24. Thuarea. 



Spikelets dioecious, in dense heads. — 25. Spinifex. 



Tribe II. — Andropogoneae. — ^Fertile spikelets with one terminal her- 

 maphrodite or female flower, with or without a male one below it. Glumes 4 

 or rarely fewer, one of the outer ones (the largest) enclosing the fruit, the third 

 smaller, thin and hyaline, sometimes wanting, the upper or flowering one very 

 thin and hyaUne, often bearing a twisted and bent awn. A palea to each flower, 

 sometimes very small or deficient in the fertile flower. Stamens 3, rarely 

 fewer. 



Sub-tribe I. — Zoysieae. Spikelets soUtary or rarely in clusters of 2 or 3, 

 inserted all round the inarticulate rachis of a simple spike or raceme. Awns 

 none on the flowering glume, none or straight on the outer ones. 



Spikelets 2, rarely 3 or 4 together on very short pedicels. Glumes usually 

 3, the larger one echinate, a minute outer one sometimes wanting, and a small 

 hyaline flowering one. — 11. Tragus. 



Spikelets in a loose spike or raceme, very narrow. Glumes 3, the 2 outer 

 ones with straight awns. — 12. Perotis. 



Spikelets single in a notched spike, with an awn at the base of the pedicel. 

 13. Setosa. 



Sub-tribe II. — ^Rottboelliese. Spikelets awnless, in pairs or rarely sohtary, 

 in alternate notches of the articulate rachis of a simple spike, one sessUe fertile 

 and more or less embedded in the rachis, the other pedicellate. Spike 

 1 -sided. 



Outer glume of the sessile spikelet hard and globular. Pedicellate 

 spikelet barren. — 7. Manisuris. 



Spike nearly cylindrical. No pedicellate spikelet. — 6. Ophiurus. 

 Spike nearly cyHndrical. Pedicellate spikelet barren or fertile. — ^5. RottboeUia. 



Sub-tribe III. — Maydese. Spikelets unisexual, the male usually pani- 

 culate, the females spicate at the base of the males or in a separate inflorescence. 

 Female spikelets below the males, the fruiting glume very hard, smooth and 

 shining. — 1. Chionachne. 



Sub-tribe IV. — ^Euandropogonese. Spikelets in pairs or threes, rarely 

 sohtary, one sessile and fertile and one or two pedicellate and male, neuter or 

 rudimentary, rarely fertile or deficient. Flowering glume of the fertile spikelet 

 usually awned or reduced to an awn. 



Spikelets in pairs along one side of a simple spike or of the spike-hke 

 branches of a simple panicle. 



Spikes single or digitate. Sessile spikelet with a male flower below 



the fertile one. — 8. Ischsemum. 

 Spikes digitate. Spikelets 1-flowered, solitary in the notches. — 2. 



Dimeria. 

 Spikes digitate. Spikelets in pairs, both 1-flowered and usually fer- 

 tile. — 4. PoUinia. 

 Spikes sohtary, digitate, or several nearly sessile on a simple rachis. 

 Sessile spikelet 1-flowered and fertile, pedicellate one male or 

 neuter. — 9. Andropogon. 

 Spikelets in pairs crowded on a short simple axis and enclosed by a large 

 bract. 4a. Spathia. 



