570 ORDER CXLIT. GRAMINACE^. 



Order CXLIL— GP.AMINA'CE.E. {Grass Family) 



Flowers usually perfect, sometimes monoecious oi- polyga- 

 mous ; the exterior floral envelopes called glumes, the interior 

 ones palece^ and the innermost at the base of the ovary, scales. 

 Glumes usually 2, sometimes single, usually unequal. Palece 

 2 ; the exterior one simple, the interior or uppermost usually 

 keeled. Scales 2 or 3, sometimes wanting. Stamens hypogy- 

 nous, 1 — 6. Anthers versatile. Ovary simple. Styles 2, 

 rarely 1 or 3. Stigmas hairy or plumose. Albumen farina- 

 ceous. Emhryo on one side of the albumen. Culms cylindri- 

 cal, fistular, jointed. Leaves with a split sheath. 



ANALYSIS. 



1. Spikelets 1 -flowered 2 



Spikelets more than 1-flowered 17 



2. Flowers in panicles 3 



Flowers in spikes 18 



3. Glumes not presant 4 



Glumes present 5 



4. Stamens 6, monoecious Zizania, 3 



Stamens 1 — 3 Leersia, 1 



5. Glumes minute 6 



Glumes not minute 7 



6. Stamens 6 Orysa, 2 



Stamens 3 Muhlenbergia, 17 



7. PaleiE awned 8 



Paleai not awned Agrosti.% 18 



8. Lower palese with 3 awns Aristida, 16 



Lower paieaj witli only 1 awn 9 



9. Paleas herbaceous .^ 10 



Paiete membranaceous or cartilaginous 11 



10. Stamen 1 CiJina, IS 



Stamens 3 Calamagrostis, 20 



11. Paleas membranaceous Agrostis, 18 



Paleae cartilaginous 12 



12. Fruit black Stipa, 15 



Fruit white Otyzopsis, 14 



13. Flowers in unilateral spikes 14 



Flowers in cylindrical spikes 16 



14. Paleae unequal Sparti?ia, 23 



Palea? equal 15 



15. Glumes unlik':^ 3f(nnsu)'u-% 40 



Glumes oibicular Pai^pnlum, 9 



Glumes lanceolate Cyjrodon, 19 



16. Paleie 2. shorter than the glumes, without awns Phlfium, 6 



Paleie 1, equal to the glumes, awned at the base Alojiecurus. 5 



Paleaj 2, the lower one awned Uordeum, 38 



17. Spikelets 2-floweved, flowers unlike IS 



Si^ikelets 2-flowered and alike, o; many-flowered 24 



18. Inflorescence paniculate 19 



Inflorescence in unilateral spikes 22 



Infloresconce not in unilateral spikes 23 



