968 



THE GRASS FAMILY. 



Panicle dense and narrow. Stems 3 to 6 inches. 



Spikelets about 2 lines long. Awns thickened at the top, 



shorter than the outer glumes 3. Grey A. 



Spikelets rather more than 1 line. Awn hair-like, shortly 



protruding 4. Early A. 



1. Tufted Aira. Aira csespitosa, Linn. (Fig. 1174.) 



(Eng. Bot. t. 1453.) 



A tall perennial, forming large, dense 

 tufts, with rather stiff', flat leaves, very 

 rough on the upper surface. Stems 2 

 to 4 feet, bearing an elegant panicle 6 

 inches to near a foot long, with spread- 

 ing, slender, almost capillary branches. 

 Spikelets silvery-grey or purplish, about 

 \\ lines long. Outer glumes rather un- 

 equal, lanceolate and pointed. Flower- 

 ing glumes scarcely projecting from the 

 outer ones, minutely toothed or jagged 

 at the top, with a fine hair-like awn in- 

 serted near their base, and not so long as 

 the glume itself. 



In moist, shady places, throughout 

 Europe and Russian Asia, from the Me- 

 diterranean to the Arctic regions, and 

 in North America. Abundant in Britain. 

 Fl. summer. The alpine A. (A. alpina, 

 Brit. EL, A. laevigata, Eng. Bot. t. 2102) 

 is a mere variety, which in its least 

 altered form only differs in its lower 

 stature, with shorter leaves, with the 

 glumes more or less enlarged, the awn adhering to it so much the 

 higher as the glume is more altered. In the commoner state the whole 

 panicle is viviparous, all the glumes being more or less elongated and 

 foliaceous, without awns, and containing only very imperfect flowers 

 or none at all. These varieties are frequent at considerable elevations, 

 or at high latitudes, and not uncommon in the higher mountains of 

 Scotland. 



Fig. 1174. 



2. Wavy Aira. Aira flexuosa, Linn. (Fig. 1175.) 



(Eng. Bot. t. 1519.) 



A much smaller and more slender plant than the ordinary form of 

 the tufted A., from 1 to 1J feet high, with very narrow leaves, rolled 



