IIT] 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. Arundo Phragmites is easily 
distinguished by the ligule (see p. 51), and the other aquatic grasses 
are quite different (see p. 39). 
Phleum 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. Behmeri, Schrad. are rare ruderal 
plants, and P. alpinum, L. is confined to the Scotch Highlands. P. 
arenarium is sharply distinct by its conduplicate leaves and habitat. 
Alopecurus pratensis has narrower and less grey-green leaves 
than Phleum pratense, its ligule is shorter and blunter, its sheath 
