88 JOURNAL AND PROCEEDINGS. 



These are safely protected during the winter season by the hard 

 compact walls ot the perithecium, which in spring crack open and 

 allow the asci to escape, and bring about a new infection of the 

 vines. While this mildew is not nearly so destructive as that variety 

 called the Downy mildew, still it is capable of wholly ruining the 

 crop of certain varieties which are subject to it, as for instance, the 

 Salem. 



Fig. 14. — Perithecium of Uncinula Spiralis, with hooked 

 arms, which give rise to the nain6 uncinula. 



The usual remedy found to be quite effectual in most cases in 

 the Niagara district, is dusting flowers of sulphur on the vines, or, in 

 hot weather, underneath them ; but a more certain and effectual 

 method is spraying the vines with the Bordeaux mixture, or the car- 

 bonate of copper early in the season. 



The Powdery Mildew of the Gooseberry (^SphcErotheca 

 mors uvcB.) — Like the powdery mildew of the grape, this is a para- 

 sitic fungus, filamentous or thread-like in growth, and only attacks 

 the surface of the host, giving it a powdery appearance. Goose- 

 berries affected, as everyone knows, are rendered both unsightly and 

 undesirable for food, and it is owing chiefly to the prevalence of 



