44 DREER’S VEGETABLES UNDER GLASS. 
ness and perfect plant health are very closely associated. 
Nature has assigned to the fungi the duty of watching perpet- 
ually for cases of disobedience of health rules, and every 
plant which suffers any loss of constitutional vigor is at once 
attacked and destroyed. The careless gardener is thus taught 
what practices to avoid in future operations. 
We believe that old wood and old soil are almost certain 
to produce ‘“damping off’’ of plants, even under what may 
be termed good management ; and a mushroom house where 
the boards are decayed is quite sure to produce unsound 
mushrooms. In the latter case we have an instance of a 
fungus preying upon a fungus. Perpetual motion seems to 
be nature’slaw. When a plant ceases to grow it is destroyed. 
Work the lazy garden. You pay rent for it all winter, 
do you not? Make it earn dividends every month of the 
year. 
