570 



ORDER CXLII. GRAMINACE.E. 



Order CXLIL— GRAMINA'CEJE. (Grass Family.) 



Flowers usually perfect, sometimes monoecious or 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. Stiymas hairy or plumose. Albumen farina- 

 ceous. Embryo 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-llowered IT 



2. Flowers in panicles 8 



Flowers in spikes IS 



3. Glumes not present 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 Oryza, 2 



Stamens 3 MuhUnbergia, 17 



7. Paleae awned 8 



Paleae not awned Agrostls, IS 



8. Lower paleae with 3 awns Aristida, 16 



Lower paleaj with only 1 awn 9 



9. Palete herbaceous 10 



Paleae membranaceous or cartilaginous 11 



10. Stamen 1 Cinna, IS 



Stamens 3 Cala?nagrostis, 20 



11. Paleae membranaceous A grostis, 18 



Paleae cartilaginous 12 



12. Fruit black Stipa, 15 



Fruit white OtyzopsU, 14 



13. Flowers in unilateral spikes 14 



Flowen in cylindrical spikes 16 



14 Palea- unequal Spartina, 23 



Paleae equal 15 



15. Glumes unlike Afoniauru*, 40 



Glumes orbicular Peupalutn, 9 



Glumes lanceolate Cynodon, 19 



16. Paleae 2, shorter than the chimes, without awns Phlettm, 6 



Pales 1. equal to the glumes, awned at the base AlopecurtU, 5 



Palea- 2. the lower one awned IJordeum, 3S 



17. Spikelets 2-flowcred, flowers unlike 18 



Bpikeleta 2-flower*i and alike, or many-flowered 24 



IS. Inflorescence paniculate 19 



Inflorescence in unilateral spikes 22 



Inflorescence not in unilateral spikes 23 



