146 THE HAUNTS OF LIFE 
roots, float freely. Now there are animals that 
browse on these plants, and other animals that 
thrive on the broken-down fragments of these 
plants, when they decay. But important as 
these big plants are, they are not so funda- 
mental as the immense number of simple 
plants that float in the surface-waters—the 
MUD AND 
MANURE | 4, 
IN 
BOX : 
FISHERMAN 
Fic. 13.—BLACKBOARD DRAWING OF CIRCULATION OF 
MatrTer. 
Bacteria break down the Mud and Manure; the results 
and the Bacteria are eaten by Infusorians; these are 
devoured by Water-fleas, and these by Fishes, and 
a higher incarnation is in Man. 
fresh-water Algez. These often make the water 
like green soup; and there are often far more 
of them in a pitcher than we can see of stars 
on a frosty night. It is on them that the econ- 
omy of the pond or lake mainly depends. 
