Ill] VEGETATIVE CHARACTERS 51 



Arundo Phrag mites, L. (Common Reed). A large 

 aquatic, reed-like creeping grass, with broad leaves (f to 

 1 in.), flat, rather rigid, acuminate, glaucous below, hispid 

 at edges. Sheath smooth, striate, bearded at mouth. 

 Ligule a mere fringe of hair. (Cf. Digraphis, p. 54.) 



Cynosurus is not very liable to confusion ; but it has resem- 

 blances to Lolium (see p. 49) and to species of Agrostis. The 

 leaves of Cynosurus are firmer, thicker, less dry, and with a shining 

 undersurface, and the sheath is only split above, and yellow below ; 

 whereas Agrostis has relatively thin and dry leaves, rough surfaces 

 and margin, distinct ridges, and converging margins as the blade 

 nears the sheath. 



Festuca elatior is easily confused with the glabrous Bromes. 

 For B. giganteus see p. 43. 



Bromus erectus is distinguished by the entire sheath, usually 

 hairy, the want of auricles, and the conduplicate — not convolute — 

 leaves. 



Agrostis has thinner, duller, and drier leaves, and no red sheath. 



AJopecurus pratensis has more depressed, flatter and broader 

 ridges than Festuca, and a longer ligule, and lacks the pointed 

 ears. 



** Ligule whitish, membranous, long, or at least well 

 developed. Sheaths not coloured or hroivn. Leaves 

 thin and rough, at least at the base. Ridges twt 

 'Very prominent, but numerous and distinct. 



Agrostis stolonifera, L. (Fiorin). Stolons, with numer- 

 ous short offsets bursting through the leaf-sheaths. Blade 

 flat, rough, tapering, with rounded ridges, and convolute in 

 bud : there are no auricles, but the blade may narrow, and 

 form ledges, as it runs into the sheath. Sheaths nearly 

 smooth. Ligule long and pointed, and often toothed at the 

 margins. The leaves vary in breadth. 



This and A. vulgaris, With, with shorter ligules, and, 

 possibly, A. canina, L. with finer leaves, are varieties of 



4—2 



