1917 



ENTOMOLOGICAL SOCIETY. §5 



in other parts. During this past year you may say both the American and the 

 Forest Teni CaterpiUars Imve become extinct on Montreal Island, while at bt. 

 Hilaire, Que., only 22 miles east, on the 24th of May this year there were 

 thousands of caterpillars in a space as large as this room; 1 should think without 

 exa-oeration there were 500 umericana webs there. A fungus disease killed ott 

 botr insects apparently and not only killed off the Tent Caterpillar, but a very 

 lar-e number of other caterpillars as well. We don't know when they are 

 comincv back, and if any record could be kept of the number of years between 

 certain outbreaks we might know when the next infestation or migration or 

 whatever it may have been is likely to occur so that we could prepare for them 

 Fruitgrowers would no doubt like to know ahead of time so that they could 



head them off. i c -i. ^^,i 



Dr Hewitt- In reference to your enquiry as to whether any definite record 

 is being kept, this is work of which Mr. TothiU has charge primarily. He has 

 charo-e of the investigations on the natural control measures of three ot our 

 niost%ommon deciduous pests, viz.: Forest Tent Caterpillar, Fall Webworm and 

 Spruce Budworm. Our idea in carrying on these investigations-which have 

 already covered a period, of four years-is to study all those factors ^^dHch go 

 'to control these pests. For that purpose we have established m the Province 

 of New Brunswick nine different points at which observations have been made 

 every year at least for the last three years and in some cases for four years, so 

 that we have exact records of what has taken place in regard to abundance, 

 parasites and other means of natural control. In addition to that we are now 

 vndertaking investigations to cover the whole of Canada so far as we can. .\ext 

 year Mr Tothill will probably be in the West making observations on the 

 occurrence and, so far as he can, the natural means of control of some of these 

 insect, particularly the Fall Webworm and the Western Forest Tent Caterpillar 

 in the' Prairie Provinces and in British Columbia, our idea being to secure as 

 thorouoh a knowledge as we can of the factors which go to control these msects 

 under natural conditions. We have been rather prone to attribute everytlimg to 

 insect parasites; that has been in some cases an assumption not based on suftcient 

 evidence and already very interesting results have come out, but of course as i 

 have said, we are undertaking to carry ou these investigations for a number ot 



year 



I have not had time to discuss this paper with Mr. Baird yet but there is 

 one point which seems to me of interest and importance. You will notice from 

 his charts that there is a certain amount of regularity in regard to the outbreaks 

 in what I would call the historical period which goes back to about the middle 

 of last century but if we call the period before that the pre-historic period so 

 far as exact observations by entomologists are concerned I think we can explain 

 the nature of the evidence of that period. I feel rather inclined to attribute 

 the apparent local restriction of the ravages as Mr. Baird has termed them in his 

 charts of the Fall Wel)worm and the Forest Tent Caterpillar not so much to the 

 fact that they were actually local but to the fact that the observations did no 

 extend over a large area. Consequently the records of abundance were confined 



to certain localities. , j t n • i +i-,o 



Prof Lochiiead: These charts are very interesting to me and 1 think tne 

 study is very timely. The charts reveal a great deal, it seems to me. There 

 is one thing that stands out and which impresses me very .much, a point 

 which applies to the Forest Tent CaterpMlar as well a-^ the Fall Webworm. it 



