38 Finger and Toe, and Wart Disease [CH. 
[N.B. Do not confuse these spores with the starch 
grains of the cells. The latter are larger, irregular, 
and not so numerous. |] 
Some of these minute spores may be found floating 
freely in the water in which the section is mounted. 
Owing to their minute size their germination is difficult 
to watch, except under a very high power of the 
microscope. In a hanging drop the following changes 
take place. A hole is formed on one side of the spore 
through which the contents emerge as a minute body 
which begins to move very slowly and in so doing 
continually changes its shape. Each one is known as a 
Myxamoeba, from its resemblance to a small animal 
which moves very similarly, called Amoeba. It con- 
sists of a naked mass of living substance known as 
protoplasm. Attached to it is a hair-like process which 
resembles those we saw on the zoospores of the potato 
disease fungus. 
In nature the spores formed in the large cells escape 
into the soil by the rotting of the host plants. Here 
they germinate and millions of myxamoebae are set 
free. The interstices of the soil are very much larger 
than these and so there is plenty of room for them to 
move about. The amount of water they require to 
move in is also small and there is sufficient in an 
ordinary moist soil. In their wanderings through the 
soil water some of them may chance to reach a rootlet 
of a cabbage plant or a plant belonging to the order 
Cruciferae. Of the large number of myxamoebae set 
free only a very small percentage probably reach a 
plant which they are capable of infecting. The others 
of course die. We see now why such an enormous 
number of spores are formed. If only a small number 
