1] SHOOTS AND NODES 15 
often found at the base of the sheaths themselves over 
these: the latter are often 
former are inconspicuous—e.g. 
most species of Agrostis, Avena, 
Festuca, &c. 
The nodes are of importance 
in the description of a few species 
only—e.g. they are usually dark 
coloured in certain Poas such as 
P. compressa and P. nemoralis ; 
they are sharply bent in Alope- 
curus geniculatus, and may be so 
in other species if “layed” by 
wind, rank growth, We. 
A point of considerable classi- 
ficatory value is the shape of the 
transverse section of the shoot, 
which is correlated with the mode 
of folding up of the young leaf- 
blades. 
In most grasses the blades are 
convolute—i.e. rolled up lke the 
paper of a cigarette, one edge 
over the other—and the section 
of the shoot is round (Fig. 7). 
conspicuous when the 
4 
7 
Fig. 5. Cynodon Dactylon. 
Plant (reduced) showing 
creeping and stolonifer- 
ous habit, and peculiar 
inflorescence of digitate 
spikes. Parnell. 
In some cases, however, the leaves are conduplicate—te. 
each half of the lamina is folded flat on the other, the 
upper sides being turned face to face inwards, with the 
mid-rib as the hinge—and in this case the shoots are more 
or less compressed (Fig. 6). 
