1918 ENTOMOLOGICAL SOCIETY. 80 



chewed holes in both sprayed and unsprayed portions. My dusted fruits were 

 90 per cent, scabby, and the check was 100 per cent, scabby. Did Prof. Caesar 

 ever try tobacco dust? 



Peof. Caesae : Not that we could call a fair test and draw conclusions from. 



Prof. Brittain : I was very disappointed. A man in New York State 

 assured me that it was a very efficient control for aphids. Green Apple Bugs 

 were present in large numbers and we tried it, with the result that the Green 

 Apple Bugs were chasing themselves around the tree just as lively as ever, and 

 we had only one casualty in the whole tree. 



Father Leopold: How many times did you apply the dust? 



Prof. Brittain: Four times. 



Prof. Caesar: Perhaps Prof. Bunting can tell us something about this. 



Prof. Buntixg: No. I may say, however, that I think it would be well for 

 fruit growers to go cautiously at the present time with dust spraying. There 

 seems to be a big difference of opinion amongst men who have been experimenting 

 with both. We know that, the liquid spray is very effective and a satisfactory 

 control for most of our orchard pests. Someone has described an ideal spray as 

 one that can be applied with the least inconvenience, in the shortest space of 

 time, will control the largest number of pests for the longest possible season. 

 No doubt dusting machines have done good service, but the fruit grower must 

 have a dust machine and also a liquid machine to spray an orchard at the present 

 time. I think it w^ould be wise for the average orchardist to go cautiously in 

 adopting the dusting machine. 



Prof. Caesar: Where the same man did the work in an orchard- at Whitby 

 the liquid spray gave much better results tlian dusting. T do not advocate the 

 purchase of a dust sprayer for the average fruit grower. 



A FEW NOTES ON THE ECOLOGY OF INSECTS. 



W. LOCHHEAD, MaCDONALD COLLEGE, P.Q. 



In its broad aspect the ecology of insects deals with these animals in relation 

 to their environment. It is evident, therefore, that a short paper such as this 

 cannot discuss adequately the whole field of relations between insects and their 

 environment, for this would require volumes. The object of this paper, however, 

 is to touch briefly upon a few aspects of the subject with the hope that more 

 attention may be given to the study of the problems involved to the end that 

 they may help in solving some of the problems relating to the control of injurious 

 insects. 



Inter-relations Between Insects and Plants. 



Long continued observations show that there are " all grades of association 

 between plants and insects from most casual contact to mutual dependence, and 

 that there are grades of fitness on both sides." (Needham, General Biology.) 

 The important part played by many insects in the fertilization of plants is 

 well known. To this end many beautiful adaptations occur among plants such 

 as in legumes, iris, milkweed, yucca, orchids, mints, figworts, honeysuckles, canna, 

 Smyrna fig, etc., but it should be borne in mind that there has been also much 

 adaptation on the part of the insects. 



