ASCOMYCETES 



223 



contains relatively large spores. According to Salmon this species 

 is indistinguishable from the Sphaerotheca found in Europe upon 

 Euphorbia. The latter is, however, not very common in Europe. 

 During the summer of 1906 a serious outbreak of gooseberry 

 mildew was reported in Europe. The fungus has spread rapidly, 

 and the result of this outbreak will undoubtedly afford European 



FIG. 88. MILDEW OF PEACH ON NURSERY STOCK 



investigators an opportunity of testing the validity of the above 

 opinion. 



Control. The American gooseberry mildew is one of the most 

 difficult of the mildews to control. English varieties of goose- 

 berries in America have proved most susceptible, and the best 

 results have been obtained by the use of a spray of relatively 

 strong potassium sulfide, I ounce to 2 gallons of water. Spray- 

 ing should be given from the time that the buds break open, and 



