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STRAWBERRY MILDEW {Sphcerotheca pannosa). 



A. Conidiophores. B. Perithecium. C. Section of Ascus showing the spores. 



Strawberry plants were seriously affected in many places 

 during the season of 1898 by the strawberry mildew, a fungoid 

 disorder which attacks first the leaves, causing them to curl 

 and shrivel up, and then the fruits as they are forming. This 

 disease makes its appearance in May, in the form of white 

 spots upon the leaves. These gradually spread and cover 

 the leaf-surfaces and extend to the fruit, covering it with 

 white filaments, which may easily be mistaken for common 

 mould. To casual observers the fungus appears to attack 

 the fruit only as it approaches ripeness, when it spreads 

 with astonishing rapidity ; but this is due to the fact that it 

 is not readily seen with the naked eye upon the fruit until 

 the latter has coloured, for with the aid of a pocket lens it 

 may be discovered upon the fruit in all stages. It is 



