42 Mr. Woods on the Genera of European Grasses. 



12. Briza. Glumes nearly equal, broad, boat-shaped. Outer palea navicular, 



heart-shaped, ventricose, keelless, obtuse, unarmed. Glumes and palese 

 membranous with a scariose margin. Seed obovate, free. 



13. Cynosurus. Spiculse attached to a neutral spike or spicula of many 

 glumes ! Fei'tile spicula 1- or more-flowered. Glumes scariose, with 

 a strong membranous keel. Outer palea membranous, with a terminal 

 seta. Panicle or spike one-sided. 



14. Dactylis. Glumes many-flowered; outer keeled, herbaceo-membranous, 



taper-pointed ; inner smaller, scariose. Outer palea keeled, with a ter- 

 minal seta. Spicule crowded. Panicle one-sided. 



15. Festuca. Glumes thinner than outer palea, which is very acute, or fur- 



nished with a point or seta, at, or very close to, the extremity. Spiculfc 

 subcylindrical, scattered. Panicle one-sided. 



1 6. Bromus. Outer palea like the glumes, herbaceous, with a scariose mar- 



gin, subcylindrical, ribbed, with a seta founded on 3 nerves from below 

 the tip. Panicle equal all round. Seed linear, convex, crested, attached 

 to the inner palea. 



It is very difiicult to establish good generic characters among the Festuca- 

 cece. KcELERiA appears to me to form a natural group, of which some of the 

 species are armed and some are not, and there does not want a slight differ- 

 ence of habit between these two divisions. The first form the genus Airochloa 

 of Link, of which K. cristata may be taken as the type. The second trenches 

 very closely upon Trisetum. The species of this genus have been ranked with 

 Aira, Festuca, Phalaris, Alopecurus, Holcus, Trisetum, Bromus, Dactylis, and 

 Cynosurus. Koeleria macilenta, with its very unequal glumes, is perhaps nearly 

 allied to Festuca Myurus, and I endeavour in vain to trace in the characters 

 given by Kunth, any diff'erence between these genera, unless, indeed, it be in 

 the seed, which, according to him, is free in this genus, and attached in Fes- 

 tuca to the inner palea. Sir J. E. Smith will not allow this character in 

 Festuca, and it certainly does not exist in all the species. The crowded and 

 shortened spicultc of Koeleria are the circumstances which first strike the eye, 

 and on these and on the compressed and keeled florets we must rely for the 

 distinction. From Trisetum. it differs in the arm, which is an awn in that 



