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THE FARMERS HANDBOOK. 



and spread with rapidity. Blue Mould especially attacks young plants 

 in the seed-bed ; and if its makes its appearance when the particular relation- 

 ship above referred to exists, it spreads so rapidly that the whole seed-bed 

 may be damaged in the course of a few days. 



fig. 3.— Adult leaf showing holes in places previously attacked by 

 Blue Mould. 



The fungus makes its appearance on the tinder surface of the leaves, which 

 appear to be covered with fluff of a faint violet tinge. This fluff consists of 

 fungus threads which come out from the leaf and branch freely, each branch 

 bearing at its extremity a small oval spore ; these spores are produced in 

 millions. Another kind of spore (known as an oospore) is produced within 

 the tissues of the host plant. It can remain dormant much longer than the 

 other form of spore, hence old diseased plants should be burnt. The fungus 



