10 Class III. Order 11. 



valve dorsal and very minute ; corolla permanent, 

 investing the seed. 



21. ALOPECURUS. Calyx two valved, one flow- 

 ered; corolla one valved; flowers spiked. 



22. TRICHODIUM. Calyx two valved, one flow- 

 ered ; corolla one valved, awuless ; flowers pani- 

 cle d. 



B. Flowers scattered, several in each calyx. 



23. PHLEUM. Calyx two valved, one flowered, 

 sessile, linear, truncate, ending in a point, inclosing, 

 and longer than the corolla. 



A 24. AGROSTIS. Calyx two valved, one flower- 



ed ; the valves acute ; corolla two valved, unequal, 

 larger than the calyx. 



25. LEERSIA. Calyx none ; corolla two valv- 

 ed, closed. 



26. UNIOLA. Calyx many valved ; spikelet 

 ovate, carinate. 



27. DACTYLIS. Calyx of two valves, many 

 flowered, one of the valves larger, longer, compres- 

 sed, cariuate. 



28. POA. Calyx two valved ; spikelet round- 

 ed at the base ; corolla two valved, the valves ovate, 

 somewhat acute, awnless. 



29. BRIZA. Calyx two valved ; corolla inflat- 

 ed, its valves heart-shaped, mostly obtuse. 



30. FESTUCA. Calyx two valved ; spikelet ob. 

 long, roundish, with pointed glumes. 



31. BROMUS. Calyx two valved ; spikelet ob- 



. A. 



.. 



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