Ix] “ SEEDS” 139 
Digraphis differs in the stout caryopsis, smaller size, double hair- 
tuft. Arundo has a long pointed palea and long silky basal hairs 
and is larger. 
Psamma arenaria, Beauv. 
Palea 11:5 mm. ovate-lanceolate, papery, 4—5 nerved, 
as rolled round the fruit about 1:3 mm. diameter, yellow, 
and with a small tuft of stiff fine hairs at the base. Mere 
trace of awn, sub-terminal. Fruit 4—5 mm. long, obovate, 
pale-brown. 
A shore-grass, not often seen as “seed”: more valuable as a 
sand-binder than as fodder, though the young shoots are grazed. 
++ Palea acuminate, and only about 4mm. long: 
caryopsis 1°4 mm. 
Digraphis arundinacea. 
A Fen-grass, but coarse and not in use except the young growth, 
and for thatching. 
Digraphis arundinacea, Trin. 
Paleze ovate-lanceolate, nerveless and awnless, but silky 
with double basal hair-tuft, and polished at the base; 
smooth, hard and shining, and closely investing the 
caryopsis which has no groove. Dark grey in colour. The 
glumes are without awns or wings, and are left behind. 
The allied Phalaris canariensis has wing-like keels to the glumes. 
Triodia also comes into this group, with short basal hairs ; but 
its broad ciliate palea, 6 mm. long, has a short mucronate point 
between two teeth (Fig. 40). 
(2) Hairs at the base forming a fluffy “web.” 
Palew thin, 2—3 mm. long. 
Poa pratensis. 
P. trivialis. 
P. compressa. 
P. nemoralis. 
