Grasses 169 
Thus the whole mass of bloom may be loose and 
spreading, like that of the red-top, or it may be 
narrow and compressed. 
Sometimes the empty glumes end in a long, 
bristle-like point, called an awn. 
Often the flowering glume is provided with an 
awn, which may be straight, or curved, or twisted. 
The problem of providing some mode of con- 
veyance for the seed has been solved by Nature, 
for various grasses, in ways as various. 
The ‘‘hedge-hog” or ‘‘sand-bur”’ grass, com- 
mon in alluvial lands, has converted its outer 
glumes into thorny coverings for the fruit (Fig. 
43): 
These catch hold of everything and everybody, 
and succeed so well in spreading the species that 
it has become a most troublesome weed. 
Uncle Sam warns farmers against it, and even 
the text-book, forgetful of scholastic calm, dubs it 
vile. 
The squirrel-tail grass long ago bore three-flow- 
ered spikelets (Fig. 44). But now the side-blossoms 
of each trio have dwindled away, and the empty 
glumes below them have undergone a transformation 
to subserve the general good, and become long bris- 
tles, which enable the matured fruit to blow away. 
