Mr. Woops on the Genera of European Grasses. 9 
in the characters of some of the included genera. An arrangement of this 
sort, where reasons are not given, will almost necessarily depend in some 
degree upon the idiosyneracy of the person who makes it, and will, therefore, 
at times appear arbitrary and fanciful to others; for peculiar characters, ana- 
logies, and affinities will strike different minds with very different degrees of 
force. His tribes are: 
, 1. Oryzec, comprising 13 genera and 61 species, of which, among European 
plants, we find only 2, Leersia oryzoides and Oryza sativa, 
2. Phalaridew, 18 genera, among which are Lygeum, Zea, Crypsis, Knappia, 
Alopecurus, Beckmannia, Phleum, Phalaris, Holcus, Hierochloa, and 
-~ Anthoxanthum. 
3. Paniceæ, 32 genera, comprising Milium (effusum), Panicum, Oplismenus, 
Setaria, Pennisetum, and Lappago. Digitaria is included in Panicum. 
This is the largest tribe in respect to the number of species, which is 
859. Of these, Panicum alone has 421. 
4. Stipaceæ, 8 genera. Those I have to notice are Piptatherum (separated 
from Milium), Achnatherum of P. de Beauvois (called by Kunth by the 
compound name of Lasiagrostris), and Stipa. 
5. Agrostideæ, 16 genera. The European ones are Coleanthus, Sporobolus, 
Agrostis, Gastridium, and Polypogon. 
6. Arundinaceæ, 9 genera, including Calamagrostis, Deyeuxia, Ammophila, 
Arundo, Ampelodesmus, and Phragmites. 
7. Pappophoræ, 7 genera. Only 1 Speniens Echinaria capitata (Cenchrus ca- 
pitatus) is found in Europe. 
8. Chlorideæ, 22 genera. I have of these, Gadon, Dactyloctenium, Lepto- 
chloa, and Spartina. 
9. Avenaceæ, 19 genera, among which we find Corynephorus, Deschampsia, 
Aira, Airopsis, Lagurus, Trisetum, Avena, Arrhenatherum, and Danthonia. 
10. Festucaceæ, 38 genera. The European ones are, Sesleria, Poa, Glyceria, 
Catabrosa, Briza, Melica, Molinia, Keleria, Schismus, Dactylis, Cyno- 
surus, Lamarckia, Festuca, and Bromus. 
11. Hordeaceæ, 8 genera, comprising Lolium, Triticum, Secale, limo, Hoe 
deum, and Ægilops. : 
VOL. XVIII. c 
