133 



_ Eather local in its distribution, and chiefly, though far from exclu- 

 sively, confined to dry upland heaths and pastures, especially over 

 chalk or limestone. Although occurring occasionally in moist meadows, 

 it is only where the soil contains a considerable portion of calcareous 

 matter. Stems smooth, from eighteen inches to two feet high. Leaves 

 usually involute, unless in moist ground, linear, roughish to the touch ; 

 the sheaths smooth. Ligule long, pointed. Inflorescence, mostly a 

 simple and rather compact panicle, with erect rigid branches. Spike- 

 lets comparatively large, ovate, or oblong, usually four- or five-flowered. 

 Glumes unequal, acute, often coloured atthe lower part. Palesevery 

 unequal, the awn of the outer one usually about twice the length of 

 the flower. 



Perennial. Flowers in June and July. 



This grass is found in most parts of Europe, but is of no agricultural 

 value, as its foliage is too short and thin to add much to the general 

 crop ; and though cattle and sheep eat it in the early part of the year,' 

 it soon becomes too rigid to be palatable to them. 



A longer-leaved variety is described and figured by Dr. Parnell in 

 his ' Grasses of Scotland,' plate 52, under the title of Trisetum pra- 

 tense, longifoUum, as found in moist shady woods near the sea in the 

 neighbourhood of Edinburgh. The only differences being referable to 

 the effect of moisture and shelter, which favour the growth and expan- 

 sion of the foliage, as well as the exaggeration of some features of 

 minor importance and consequent alteration of the general aspect ; its 

 claim to be considered a permanent form is at present very doubtful. 

 Similar equivocality attaches to the two following, of which, however, 

 we give figures and descriptions as of distinct species. It may be 

 farther questioned, indeed, whether Avena pubescens, plate CXVI, is 

 not another form of the protean A. pratensis, an admission that would 

 tend far towards rendering the differential features on which our three 

 sections of the genus Avena are founded, definitive characters of so 

 many solitary species, instead of marking the limits of a series of 

 groups. 



Avena alpina. Alpine Oat Grass. Plate CXIV. 



Panicle erect, more or less simple and compact. Spikelets erect, 

 oblong, compressed, four- or five-flowered. Flowers about the length 

 of the glumes, hairy at the base. Leaves flat ; sheaths rough. Ligule 

 acute. 



Avena alpina. Smith. E. B. ed. 2. 165. Lindley, synopsis. Hooker, 

 Brit. Flora. A. planiculmis, E. B. 2141. A. pratensis, var., 

 modern botanists generally. 



The English Botany figure was drawn from specimens of this grass, 

 gathered by the late Mr. G. Don, who found it growing about the 

 summits of the Highland mountains of Scotland. It was at first con- 

 sidered to be the Avena planiculmis of Schi-ader, but the error was 



