50 Mr. Woods on the Genera of European Grasses. 



That the calyx is wanting in Leersia, Lygeum, Coleanthus, and Nardus. 

 That it is setigerous in Sesleria, Phleum, Polypogon, Lappago, Lagurus, Hor- 



deum, JEgilops, and sometimes in Triticum and Elymus. 

 That Psilurus, and sometimes Erianthus, and according to some authors, 



Festuca myurus, F. bromoides, and F. uniglumis are monandrotts. 

 That Imperata, Erianthus sometimes, Anthoxanthum, Crypsis aculeata, Bro- 



mus diandnts, Coleanthus, and the perfect flower of Hierochloe, are dian- 



drous. 

 That Nardus, Lygeum, and Echinaria have only one stigma. 

 That the styles are united in Sesleria, Spartina, and some species of Alope- 



curus. 

 That Oryza has 6 stamens. 

 That Andropogon, Sorghum, Lappago, and Hordeum have some of their spi- 



culae barren, and therefore belong to the Linnean class Moncecia, or 



rather, perhaps, to Polygamia. 

 That Zea alone of all Grasses found or commonly cultivated in Europe has 



fertile flowers without anthers, and that these and the barren flowers are 



in different parts of the plant. 



A. Barren and fertile inflorescence separate ! 



17. Zea. Barren spiculse 2-flowered, in a terminal panicle. Fertile, in a 



dense spike, 1 -flowered, with an exterior rudiment. 



B. Perianthium hardening into a 2- or 3-seeded nut. 



1 8. Lygeum. Glume 0. Spiculae enveloped in silky hairs. Outer palea thick 



and firm ; inner scariose. 



C. Spiculae in opposite rows on an alternately channelled rachis. 

 1. Spiculae 2 or more flowered, all perfect. 



68. Brachypodium. Glumes unequal, ribbed, much smaller than the outer 



palea. Spiculse on short stalks. 

 67. Lolium. Spiculse placed edgewise on the rachis ! Lower glume very 

 obscure, or wanting. 



69. Triticum. Glumes nearly equal, opposite, broad, embracing the solitary 



