70 THE GENERA AND THEIR SPECIES. 



Aira. Plates xii. and xiii. A VENEM. 



$6. Gcvspitosa 42 in. Tufted Hair Grass. Panicle spreading ; 

 ligule long and pointed ; leaves rough 

 downwards ; awn hardly longer than 

 palea. 



37.flexuosa 12. in Wavy Hair Grass. Panicle spreading 

 and wavy ; ligule short and truncate. 



38. canescens 10 in. Grey Hair Grass. Panicle close ; awn 



club-shaped. 



39. prcecox 6 in. Early Hair Grass. Panicle close ; ligule 



long, sheathing, and torn. 



40. caryophyllea 12 in. Hair Grass. Panicle spreading ; ligule 



ong and pointed ; sheaths rough upwards ; 

 awn twice as long as palea. 



36. A. ccespitosa. Pastures and shady wet places, ranging 

 through the Temperate and mountainous regions of the Northern 

 Hemisphere. July and August. Root perennial, fibrous, densely 

 tufted. Stem decumbent, then erect, leafy, rough. Leaves linear, 

 striped white and green when held to light, rigid, cartilaginous ; 

 ribs dark green, thick and prominent, each with a line of hairs 

 along its edge ; blades rough downwards, margins rough, apex 

 acute. Sheaths ribbed, uppermost longer than leaf ; ligule long, 

 acute, and torn. Panicle pyramidal, large, diffuse, glossy ; 

 branches rough and slender. Spikelets numerous, erect, small, 

 silvery ; two florets. Glumes nearly equal, upper glume ribbed, 

 lower not ribbed, keels rather rough. Outer palea shorter than 

 glumes, lanceolate, apex toothed, five ribs, base hairy, awned from 

 middle ; awn slightly longer than palea ; inner palea narrow, 

 shorter than outer palea. 



This tufted Hair Grass is found almost everywhere, but most 

 frequently in clayey moist places. It is recognisable by its 

 light, large, open panicle, rough, hard leaves and its habit of 

 growing in tussocks, which, however, is not indulged in by its 

 variety, A. lutescens. It is not an easy weed to get rid of, as 

 when the tussock is destroyed a plentiful growth of young shoots 



