238 GRASSES OF BRITAIN. 



AiRA FLEXUOSA. 



Wavy Mountain Hair- Grass. 

 Plate evil. 



Specific Characters. — Awn arising from a little above the base of 

 the outer palea, and extending about one-fourth of its length beyond 

 the summit of the palea. 



Description. — Root perennial, fibrous, woolly in sandy ground. 

 Stem hollow, erect, flattish, smooth, striated, and frequently of a pur- 

 ple tinge, from twelve to eighteen inches high, bearing three or four 

 leaves with roughish, striated sheaths (the roughness is distinctly felt 

 by passing the finger down the sheath) ; upper sheath about twice 

 the length of the leaf. Ligule of upper sheath prominent, about as 

 long as broad, almost always cloven and rounded at the summit. 

 Joints three, smooth. Leaves very narrow, fleshy, subterete, the 

 upper leaf rough the whole length, those from the root smooth, 

 except towards their points ; in dry exposed situations the radi- 

 cal leaves are short and curved; while in woods or shady places 

 they are long and of a dark green, the base surrounded with brown, 

 thin, withered sheaths of former years. Panicle erect, spreading, the 

 branches slender, rough, slightly wavy, mostly triple-forked ; rachis 

 wavy, smooth below, rough above. Spikelets of a brownish glossy 

 copper colour, composed of two glumes and two awned florets with 

 the rudiment of a third. Glumes rather unequal, membranous, with- 

 out lateral ribs, slightly roughish on their keels. Florets concealed 

 within the glumes ; outer palea of lowermost floret notched or jagged 

 at the summit, hairy at the base, very faintly five-ribbed, furnished 

 with a slender rough awn arising from a little above the base and 

 extending about one-fourth of its length beyond the summit. Inner 

 palea about the length of the outer, very thin, acute, often bifid, mi- 

 nutely fringed at the margins. Second floret rather the smaller, on a 

 short hairy footstalk about one-fifth the length of the floret ; in other 

 respects the two florets are similar. Styles short. Stigmas promi- 

 nent and feathery. Filaments slender. Anthers notched at each 

 end. Scales pointed. 



Obs. — Airajlexuosa is distinguished from Aii'a ccBspitosa in the li- 

 fjnle being obtuse, and about as long as broad ; awn extending about 



