198 



top of the round box, above the division, are sprayed vyith cool emulsion, and those 

 in the bottom of the round box were not sprayed. The reason that I enclose the last 

 is that we have had some very cold weather, 30° below zero, and I hoped ijt had injured 

 the worms. The trees that were sprayed were done 19 days ago, but there was ice 

 on the trees and I could not very well collect them before." 



The cold had in no way, however, inconvenienced these hardy little enemies of 

 the orchard. Upon receipt of the sprayed twigs they were found to be covered with 

 the small case-bearers. The odour of the emulsion was quite strong, but most of 

 the larvae were still alive. My thanks are particularly due to Dr. Young for the 

 very careful manner in which he has tried every experiment I have suggested 

 and has at great trouble written the full accounts of the progress of the work. Upon 

 enquiring from him when these caterpillars first appeared, he says: " Wo did not 

 notice the case-bearers last spring till they had done great injury to the leaves. The. 

 apples on the Duchess trees were then about the size of pease, and the- trees heavily 

 loaded ; my brother then came and told me that the leaves were badly eaten. We 

 examined and found the case-bearers. My brother, whoso time is occupied in the 

 orchard, says that he has seen them for six or seven years, but not so many of them. 

 Speaking safely, I think they caused a loss of one-half of the crop, for this was the 

 best bearing year, and we had only 458 barrels, whereas we have had from 800 to over 

 1,000 barrels off the same trees. Besides this, the apples were not at all as good as 

 formerly." 



I received also specimens of this same insect in July from Eev. F. J. H. Axford, 

 of Port Williams, Nova Scotia, where it had occurred in small numbers. It has 

 however, as far as I can learn, nowhere else occurred in the devestating numbers 

 recorded by Dr. Young. 



From the above experience, spraying with Paris Green, 1 lb. to 200 gallons 

 of water, directly the leaves begin to unfold, and again after the flowers have fallen, 

 wouW probably be the best remedy. I bred a few chalcid parasites from the cases ; 

 but unfortunately they have been mislaid. 



THE PEAE-LEAF BLISTER. 

 {Phytoptus pyri.= Typhlodromus pyri, of Sheuten.^ 



Fig. 5. — Cluster of infested leaves : a, upper surface of leaf; b, lower surface; «, two galls enlarged. 

 (Figure kindly lent by Prof J. H. Comstock.) 



Attack. — Eeddish spots, irregular in shape, about ^ inch in diarfieter and 

 frequently confluent. These appear on young pear trees early in spring, and as the 



