1919 ENTOMOLOGICAL SOCIETY. ' 93 



still colder parts such as Ottawa and the St. Lawrence River valley aboi;t the second 

 week in July. 



The second application should be made when the first has begun to disappear 

 or usually in from two to three weeks. In wet seasons like the summer of 1915, 

 a third application about ten days after the second will be necessary. Two years 

 should almost completely destroy the insect in any orchard provided that infested 

 orchards are not situated close by. In such case every effort should be made to 

 have these treated also. 



In all orchards every tree whether bearing fruit or not should be sprayed, 

 because the adults often frequent such trees until egg laying begins. 



As to the mixture to use, in 1914, 1915. and 1916 we used molasses along with 

 arsenate of lead, but in 1917 and 1918 omitted the molasses and found that the 

 results Avere equally good. This is fortunate, for molasses tends to cause the spray 

 to wash off more quickly, sometimes burns the foliage, adds to the cost, and may 

 cause complaints from beekeepers, though these complaints are not justified. We 

 therefore recommend the use of from two to three pounds of the paste form or one 

 to one and a half pounds of the powder form of arsenate of lead to forty gallons 

 of water. We believe that heavy rather than light applications of the mixture 

 should be made, especially if only two are given, because adults continue to emerge 

 for a. period of six weeks or more, and so the poison must remain on the trees to 

 kill them before they can lay their eggs. Heavy applications remain on longer 

 than light. 



OUR GARDEN SLUGS. 

 Geo. Maheux, Quebec. 



It is only during about the past thirty years that the Mollusks of the Province 

 of Quebec have attracted the attention of naturalists and have been the object 

 of their studies. As long as they remained inoffensive, or nearly so, they were 

 objects of interest only to amateurs, on account of their strange forms, some pre- 

 senting the richest of garments, of admirable color and composition, while others are 

 of a viscous and almost repulsive nakedness. The day these Mollusca Gasteropoda 

 came to feed in our vegetable gardens their economical stature changed hastily 

 and the extent of their havoc soon necessitated the interference of zoologists. 

 Of course, the first thing was to acquaint oneself with the species composing 

 this branch of invertebrates ; specialists devoted themselves to this study and sys- 

 tematic treatises were soon published ; and from this departure, experimentalists 

 endeavored to discover an efficient remedy against these new ravagers. 



In 1890, very few text-books bearing on this subject were in existence, 

 except, perhaps, the Manual of Conchology of Tryon, then published by Mr. 

 Pilsbury, of Philadelphia, and a few other works of smaller importance. The 

 following year (1891) our great Canadian naturalist. Abbe Provancher, published 

 a new part of his Canadian Fauna, an illustrated book of over 150 pages, under 

 the title of : " Les Mollusques de la Province de Quebec," Part I ; Pteropoda, 

 Cephalopoda and Gasteropoda. Provancher had been, for a long time, collecting 

 specimens of these animals. From his book entitled : " Voyage aux Antilles," 

 we can see that he was taking a great interest in this study and that he then 

 made a lar^e 2:athering of remarkable shells. 



