36 ]\Ir. Woods on the Genera of European Grasses. 



and as long, or nearly as long as the spicula, and this contains, except in 

 Lagitrus and in .Irrlienatlierum, two or more perfect florets. With the exce|>- 

 tion of the latter genus, llie tendency of this tribe is to perfect its lower florets, 

 while the upper ones are frequently imperfect and tabescent. The paleœ are 

 unequal in substance, the outer being much the firmest, frequently strongly 

 ribbed, and generally with a scariose margin or extremity. The inner is alto- 

 gether scariose, except on the two keeled nerves, permanent, and embracing 

 the seed. A jointed and tv\/isted awn rises from the back of the outer palea, 

 but this is sometimes wanting. Tlie inflorescence is in a panicle, spreading 

 all round, except in Gaadinia, where it is in a spike, the spicula.^ being in 

 opposite rows on a fragile, alternately channelled rachis. The inequality of 

 substance in the palete, and the greater firmness of the outer, as compared to 

 the glumes, may be added to the marks already pointed out, which distinguish 

 these plants from the Arundniaceœ. They are separateil from the Festucaceœ 

 chiefly by the nature of the awn, by the stiff hairs at the base of the floret, 

 and by the greater comparative length of the glumes. Unfortunately, the stiff 

 hairs at the base of the floret do not always exist ; nor is the dorsal, genicu- 

 late awn always ])resent. The awn or seta among the Festucacece is never 

 geniculate, although it is somewhat curved and twisted in some species of 

 Bromus ; but the awn in the ^Ivenacew arises from the substance of the paleœ, 

 and never from the union of several nerves as in that genus, while in tiie other 

 srenera of Festucaceœ it is evidently a mere continuation of the midrib. 

 The genera are : 



1. .-lira. Glumes 2-flowered, without any rudimenr. Outer palea nerveless, 



included. Awn, if any, dorsal, geniculate. 



2. Deschampsia. Glumes keeled, containing (but not including) 2 perfect 



florets, and the rudiment of a tliird more or less developed. Awn dorsal, 

 straight. 



3. Lagurus. Glumes 1 -flowered, scariose, ending in a long fringed seta! 



Outer palea nerved, ending in two long setœ and an intermediate genicu- 

 late and twisted dorsal awn. 



4. Trlsetum. Glumes 2 — G-floM'cred, membranous, not exceeding the florets. 



Outer palea scariose, without nerves or any distinct keel, ending in two 



