FUNGUS DISEASES 97 



weather or in a stagnant atmosphere ; it will be less likely 

 to attack Violets in frames if careful attention is given to 

 ventilating the frames ; in severe cases the plants may be 

 syringed with potassium sulphide, at the rate of i oz. of 

 potassium sulphide (or liver of sulphur) to i\ gallons of 

 water. Dissolve the potassium sulphide in a quart of hot 

 water ; then make it up to 2 \ gallons with cold water. 



Ascochyta violae. This is another disease that Violets 

 have exhibited in this country when cultivated in frames. 

 An attack may be identified by the presence of scorched- 

 like patches on the leaves. From these patches numerous 

 minute spores are produced, and these, falling from the 

 leaves to the ground, are liable to perpetuate the disease. 

 Where a bad attack is experienced, the most satisfactory 

 plan is to burn the plants, sterilise the soil or remove it 

 to an out-of-the-way part of the garden, and thoroughly 

 disinfect the frame before planting fresh stock. When the 

 plants are well established, the plant and soil may be 

 sprayed at intervals of a fortnight with potassium sulphide, 

 at the strength of i oz. to 3 gallons of water. 



