Ill] VEGETATIVE CHARACTEKS 61 



Arena puhescens, Huds. (Downy Oat-grass). A variety 

 of A. pratensis (see p. 47), but less densely tufted, and 

 the leaves fiat and pubescent, and especially the sheaths 

 very pubescent. Ligule ovate-acute. Shoots flat. Dry 

 districts, and a weed. 



Avena Jlavescens is not easily confouuded with any other grass if 

 well grown. All the Poas otherwise like it are glabrous, and without 

 the ridges. The same applies to A. puhescens. 



Arrhenathenom is also glabrous, its leaves narrower, its ridges 

 much flatter and broader, and its ligule is hairy outside (see p. 56). 



Brachypodium sylvaticum, Beauv. (Wood False-brome). 

 Kather slender, perennial. Leaves flat and devoid of 

 ridges ; long, very thin and dry, limp, slightly tapering 

 below, hirsute. Sheath round, hairy. Ligule fairly long, 

 obtuse, toothed. Copses, &c. Useless. 



Brachypodium pinnatum, L. (Heath False-brome), is 

 a species growing in the open, with narrow, firm, rigid, 

 erect leaves, hardly hairy; with distinct ridges, and 

 tending to roll up. Ligule fringed with hair. Open 

 heaths. Useless. 



The only grasses likely to be confounded here are the Bromes, 

 and they have entire sheaths. 



