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Garden Work 
handled. Care should therefore be taken to see that fresh 
plants are free from this disease. 
In the early stages the roots are seen to be somewhat 
swollen, having in places a gradual swelling, This swelling 
must not be confused with that produced by the Cabbage 
Gall Weevil, which is abrupt, and contains in the centre 
of it a small white grub. That produced by the Club- 
root, however, is gradual, and in the young stage extends 
through the whole root. If such swellings are cut through 
with a knife they are found to be quite solid. 
If the ground is infected with the spores of this disease, 
and perfectly clean and healthy plants are injured by insects, 
or by tools when working in the garden, some of the spores 
may come into contact with these injuries, and, entering 
the tissue, will there develop. This disease does not form 
hyphae or mycelium, but when the spore germinates it 
simply produces a gelatinous - looking substance, called 
plasmodium, which, as it grows, absorbs the contents of 
the cells, and also causes them to grow much larger. 
This plasmodium also goes from cell to cell, absorbing 
their contents in its course. New cells are formed, and 
these in turn become affected by the disease, until the large 
clubroot-shaped mass is formed at the root of the Cab- 
bage, Cauliflower, &c., or the large swellings and nodules 
on the root of the Turnip. 
When the disease is full grown it commences to form 
spores. This is done in a rather curious way. The 
plasmodium which has filled the cells simply forms itself 
into little rounded bodies or spores. By the time these 
spores are formed the swollen portion has begun to decay 
and the spores are liberated in millions into the soil. 
