^564 Mr Macgillivray''s Description of a Species of Aira 



granite of the Loch-na-gar groupof mountains 'm August last, I 

 have found it to be apparently A. montana of Linnaeus, although 

 from the slender means which a person thrown entirely upon his 

 own resources can possess, I shall not be surprised to be inform- 

 ed that it is something else. It is, at all events, different from 

 any species or variety hitherto admitted as British. 



A montana? Linn. Leaves involute ; panicle close, with flexuous branches ; 

 florets longer than the calyx, somewhat abrupt and lacerated ; awn from be- 

 low the middle of the outer valve, shorter than the floret. 



Root of numerous long, branched fibres. Stem about a foot high, oblique 

 at the base, afterwards erect, two-jointed, striated, smooth, pale green, brown 

 on the exposed knot. Leaves forming a tuft at the base, linear involute, 

 acute, sheathing, the sheath of the uppermost, which is extremely short, reach- 

 ing to near the panicle, smooth on the back, scabrous on the edges and the 

 nine prominent ribs of the upper surface. Liguhe obtuse, lacerated, white. 

 Panicle close, four inches long, with angular roughish shaft, semiverticillate, 

 quaternate, smoothish branches, which with the shaft are flexuous, and shin- 

 ing dark reddish-puT pie flowers, whitish at the tips. Florets longer than the 

 calyx. "Valves of the calyx unequal, ovate, keeled, the outer serrato-dentate 

 towards the slighth' cleft tip, the inner larger, lacerated toward the end and 

 cleft. There are always three florets : the lower on a very short stalk, its 

 outer valve ovato-lanceolate, with a tuft of erect hairs at the base, and denti- 

 culate on the keel, rather abrupt, with five tapering acute terminal segments, 

 the inner elliptical, deeply cleft, sparsely ciliated, the awn denticulate, nearly 

 straight, from below the middle of the outer valve, and almost as long as it. 

 The second floret on a longish hairy stalk, w^hich is suddenly bent at the top, 

 where it bears a tuft of hairs, smaller than the first, sparsely denticulate on 

 the keel, terminated by three tapering segments, and awned like the first, 

 the awn shorter. The third floret on a similar stalk, rudimentary, denticu- 

 late on the keel, with a very minute awn not reaching beyond the middle of 

 the outer valve, which is simply cleft, the inner valve acute. The two lower 

 florets are perfect, the third abortive, sometimes antheriferous. The outer 

 valve of all is pale-green at the base, reddish-brown in the middle, whitish at 

 the tip, the inner valve white. Filaments short; anthers linear, bifid, yellow. 

 Gennen roundish ; stigmas very short, feathery, recurved. Scales in the two 

 lower florets only, lanceolate, very minute, scarcely longer than the gennen. 



With A. coEspHosa this species has little affinity in its general 

 appearance, although the flowers, which are about 60, resemble 

 those of that species, which has commonly more upon a single 

 branch of its panicle. In A. ccBspitosa, the calycine valves are 

 nearly equal, and both rough on the keel ; the outer valve of 

 the corolla is quite abrupt, with several segments, each of which 

 is abrupt and lacerated ; the awns come o£F close to the base ; 

 and the scales are much longer than the germen. From A. 



