THE CANADIAN ENTOMOLOGIST 187 



examination of the incrustations revealed nothing of a parasitic 

 nature. . 



The next year similar injured twigs were submitted for ex- 

 amination in even greater quantity. In particular, a number of 

 nursery firms complained of heavy loss to their Northern Spy 

 stock from being rendered so unsightly as to be quite unmarket- 

 able. One firm, situated in the Okanagan, was compelled to de- 

 stroy- a large quantity of Northern Spy stock, as a result of this 

 trouble. It appeared, on further examination of affected twigs, 

 that the year following the appearance of the trouble, the injured 

 areas frequently dropped out, thus rendering the injured tree 

 more unsightly than before. Further examination of the incrusta- 

 tions still revealed nothing, but so serious had the situation be- 

 come, that it was decided to follow the matter up carefully, in 

 order to determine definitely the cause of the trouble. 



The writer left British Columbia in the fall of that year and 

 was unable to prosecute this matter further. However, Mr. J. 

 S. Dash (5), then working under the direction of the Inspector 

 of PYiiit Pests, examined a number of injured twigs during the 

 month of October. He found them to contain hundreds of hiber- 

 nating mites, whose identity could not be ascertained with cer- 

 tainty at the time, since they were immature. At the request of 

 the writer, a number of affected nursery trees were sent to Truro, 

 kept over winter and planted out the following spring. In July 

 the silvery appearance, characteristic of the work of Phyllocoptes 

 schlectendali, became apparent on the leaves, which, on examina- 

 tion, were found to be coN'ered with mites belonging to this species. 



It would appear from our observations that the mites, which 

 feed on the foliage during the summer months, make their way to 

 the twigs in the autumn where they enter an old egg blister of 

 the Rose Leaf-hopper (Empoa rosce) , a common apple pest through- 

 out the province, or of the Apple Leaf-hopper (Empoasca mali) 

 or through a lenticel, and there they develop their hibernating 

 incrustations, which render the affected trees so unsightly. As 

 an enemy of nursery trees and particularly of Northern Spys, 

 this mite is, therefore, of considerable importance, since stock 

 so disfigured is unmarketable. The actual harm done to such 



