Ill] VEGETATIVE CHARACTERS 55 



flat, firm, long and broad (1 in.) below. Mid-rib and veins 

 numerous, and prominent below. Stoloniferous : branches 

 extra-vaginal, often with deep red basal scales. Sheaths 

 with much overlapping membranous margins, with a 

 collar-like ledge above. Ligule long and somewhat acute. 

 Wet ditches, &c., of no value (Figs. 7, 14). 



For distinction between Digraphis and Dactylis see p. 41. Poa 

 pratensis is at once distinguished by its flattened shoots, more 

 rounded leaf apex and shorter ligule. Arnndo Phragmites is easily 

 distinguished by the ligule (see p. 51), and the other aquatic grasses 

 are quite different (see p. 39). 



Phleuni pratense, L. (Timothy-grass). No stolons, 

 but bulbous on dry ground. Early, and a heavy cropping 

 hay grass : also excellent pasture ; branches intra-vaginal, 

 but burst the glabrous sheaths. Old sheaths fibrous. 

 Leaves short, convolute, with scabrid margins owing to 

 deflexed teeth : ridges obsolete above, no keel ; broader 

 and greyer green than Alopecurus. Ligule short on 

 radical leaves, thin. Pastures. Perennial. 



The smooth ligule, deflexed marginal teeth, and no keel 

 distinguish it from Arrhenatherum. 



Phleum arenarium, L. (Sand Phleum). Shoot annual, 

 with no bulbs. Leaves broad, flat and glabrous, but rough 

 at the edges, with descending teeth. Ridges low and flat. 

 Sheaths smooth : leaves conduplicate. Ligule long. Sandy 

 coasts, &c. A weed. 



Phleum asperum, Jacq. and P. Bcehmeri, Schrad. are rare ruderal 

 plants, and P. alpinum, L. is confined to the Scotch Highlands. P. 

 arejiariuni is sharply distinct by its conduphoate leaves and habitat. 



Alopecurus pratensis has narrower and less grey-green leaves 

 than Phleum pratense, its ligule is shorter and blunter, its sheath 



