February, '17] HEWITT: INSECT BEHAVIOUR 81 



juries by the flea-beetle. Both pests, when abundant, may destroy 

 seedhngs as well as retard growth. Moreover, there exist in the 

 screened frames superior conditions for the growth of the plants. A 

 larger percentage of the radishes establish themselves since there is less 

 evaporation of moisture and no baking of the soil to check their devel- 

 opment. Incrustation of clay soil, accompanied with hot weather 

 and slight precipitation, affords conditions that are exceedingly un- 

 congenial to the radish and as fatal as the insect enemies to the pro- 

 duction of roots that are mild, succulent and tender. 

 Adjournment. 



Morning Session, Friday, December 29, 1,916, 9.4-5 a. m. 



Vice-President G. A. Dean: The first paper on the program will 

 be read by Mr. Marcovitch. 



THE STRAWBERRY WEEVIL IN MINNESOTA 



By Simon Marcovitch, SL Paid, Minn. 



(Withdrawn for publication elsewhere.) 



Vice-President G. A. Dean: As Doctor Hewitt has now arrived, 

 we will next listen to the annual address of the President. 



INSECT BEHAVIOUR AS A FACTOR IN APPLIED 

 ENTOMOLOGY 



By C. Gordon Hewitt, D.Sc, F.R.S.C, 

 Dominion Entomologist, Ottawa, Canada 



In determining the choice of a subject for my address I have been 

 guided by a feehng that, owing to the extraordinary progress that has 

 been made in the knowledge and methods of applied entomology dur- 

 ing recent -years, the time at my disposal could not be occupied to 

 better advantage than by an examination of what I believe to be 

 fundamental to an adequate appreciation of the problems with which 

 we have to deal and their successful solution. 



We have accumulated an enormous mass of facts relating to insect 

 life in all its manifold relations to the welfare of man, and many of 

 these facts have furnished us with the means of determining methods of 

 preventing or controlling the noxious effects of insect activity. But 

 it would appear to me that we have reached a stage where our accu- 

 mulated knowledge is rather like a city that has developed along the 



