90 SPIKELETS AND [CH. 



Lepturas, Spartina, Gynodon, Gastridium, Lagurus, Poly- 

 pogoHy Leersia. 



Spikelets with one perfect flower and one or more male or 

 rudimentary ones. 



Digr aphis. Holcus. 



AntJwxanthum. Arrhenatherum. 



And the rare genera Hierochloe and Panicum. 



Spikelets with at least two perfect flowers. 



Molinia. Triodia. 



Arundo. Sesleria. 



A vena. Kceleria. 



Aira (some species). Melica (one species). 



Brom us. Briza. 



Cynosurus. Poa tHvialis. 



Dactylis. Catahrosa. 



Spikelets with at least three perfect flowers and usually more. 



Elymus. Festuca. 



Agropyrum. Poa. 



Brad ly podium. Glyceria. 

 Loliuni. 



Inflorescence, a spike of single spikelets. 



Agropyrum. Lolium. 



Brachypodium. Nardiis. 



And varieties of Festuca Myuriis and F. loliacea, &c. 



Inflorescence, a spike of pairs or tufts of three or 

 more spikelets. 



Elymus (pairs). Cynosurus (clusters). 



Hordeum (threes). 



Inflorescence, a cylindrical closely tufted spike-like panicle. 



Phleum. Psamma. 



A lopecurus. Anthoxanthum. 



