GRASS FAMILY 549 



Sub-order I. Panicdcecs. — Spikelets jointed upon the pedicel; 

 rachilla persistent; glumes 1 — 4, only the uppermost enclosing 

 a perfect flower. 



Tribe i. Panicece. — Flowering glume 3- or more-nerved, 

 not awned 



I. Digit Aria. — Glumes 4 ; pedicels of spikelets naked or hairy; 

 flowering glume 3-veined, not awned. 



*2. Echinochloa. — Glumes 4 ; flowering glume 5-veined, mu- 

 cronate or awned. 



♦3. Setaria.— Glumes 4 ; pedicels of spikelets bristly. 



4. Spartina. — Glumes 3 ; spikes upright, in a raceme. 



Tribe 2. Oryzece. — Spikelets laterally compressed ; flowering glume 

 and pale i-nerved 



5. Leersia. — Spikelets in a loose panicle ; empty glumes 

 absent. 



Sub-order II. Poacea. — Spikelets rarely jointed upon the pedicel; 

 rachilla deciduous ; glumes 3 or more, the two lowest empty 



Tribe 3. Phalaridea;. — Spikelets distinctly stalked, laterally com- 

 pressed; rachilla not produced beyond the uppermost glume; glumes 

 3 — 6, uppermost only with a perfect flower; pale absent or 1- 

 nerved. 



6. Phalaris. — Glumes 6, awnless ; stamens 3. 



7. Anthoxanthum. — Glumes 6, 2-awned ; stamens 2. 



8. Hierochloe. — Glumes 6, 2-awned, with 3 stamens each ; 

 uppermost perfect flower with 2. 



9. Alopectjrus. — Spikelets jointed on the pedicel in a spike- 

 like panicle ; glumes 3 or 4; flowering glume with dorsal awn ; 

 stamens 3. 



Tribe 4. Agrostidece. — Spikelet 1 -flowered ; glumes 3 ; flower 



perfect; pale 2-nerved 



* Rachilla not produced beyond flowering glume 



10. Milium. — Panicle loose ; flowering glume hardening round 

 fruit ; no awn. 



II. Phleum. — Panicle dense, cylindric, spike-like; flowering^ 

 glume enclosing the fruit. 



12. Mip.6ra. — Spikelets in a i-sided raceme, dorsally com- 

 pressed, awnless. 



13. Agrostis. — Panicle loose; spikelets very small; flowering 

 glume transparent. 



