68 ARIA C^SPITOSA. 



rough, and supporting four or five narrow, rough, coarsely-ribbed, 

 acute leaves with rough striated sheaths, the uppermost one ex- 

 tending considerably beyond its leaf, and having a lengthy, mem- 

 branous, acute ligule at its apex. Joints smooth and very strong. 

 Inflorescence compound panicled, and exceedingly handsome. 

 Panicle when first expanded drooping, afterwards becoming 

 upright, with the branches spreading in all directions. Branches 

 and rachis rough. The spikelets are small and numerous, con- 

 sisting of two or three horned florets. The calyx consisting 

 of two equal-sized acute glumes, the upper one three-ribbed 

 and the lower one destitute of lateral ribs. Of the two paleee' 

 the exterior one of the lowest floret not equal in length to 

 the glumes, membranous, base hirsute, destitute of lateral ribs, 

 jagged on the summit; a slender awn starts from a little above 

 the base as far as the apex of the palea. The inner palea rather 

 shorter, linear, margin entire, and also membranous. Length 

 from two to five feet. 



Aira alpina differs, on account of the awn commencing in 

 that species slightly above the centre of the outer palea; whilst 

 on the other hand, Aira flexuosa has the awn of the lower 

 floret protruding above one-third its length beyond the glumes. 

 There is a viviparous variety of Aira ccespitosa, known under 

 the name of variety Vivipera, which has been found on the 

 Clova mountains. It is an interesting ornamental variety, worthy 

 of extensive cultivation as a border flower in gardens. Dr. 

 Parnell describes two varieties, namely, " Longiaristata" and 

 "Bremfolia." The variety Longiaristata diff"ers in having the 

 awn of the outer palea extending one quarter of its length 

 beyond the apex of the palea, and in having the spikelets of 

 a rich chocolate colour. Found on the mountains in Perthshire, 

 between three and four thousand feet above the sea level. The 

 variety Brevifolia is distinguished by the very short radical leaves. 

 It is found growing near the summit of several of our highest 

 Scotch mountains. 



This species usually flowers in the beginning of July, and 

 ripens its seed early in September. 



Door-mats and basses are made of the hay of Aira cesspitosa, 

 and for this the Grass is much in repute by rural cottagers. 



The illustration is from a plant growing on the edge of the 

 lake at Highfield House. 



