31 



Nectarophora destructor. — This Pea louse, which is probably the 

 largest of Aphids, made its appearance on our Sweet Peas in 1902. After 

 an absence of about two weeks in July I found, upon my return, that a 

 row of sweet peas which had been left in the best possible condition, was 

 all dried up and rusted. Upon examining the lower parts of some plants 

 which still had a few green leaves remaining, large green lice were 

 observed which only too clearly indicated the fate of the other plants. 

 These proved, upon examination, to be nectorophora destructor. This was 

 the first and only time that I have seen it ; although the peas were carefully 

 watched the following summer no traces of them were found. 



Conclusion. — It is felt that some will undoubtedly remark that I have 

 given no proof that the climate of this eastern part of Quebec was respons- 

 ible for the disappearance or unhealthy development of the insects above 

 mentioned. These noxious insects are often preyed upon by many species 

 of parasites which follow in their wake and wage war upon them. How- 

 ever, I observe that usually these parasitic insects appear only after the 

 noxious forms have existed in a locality for a period of at least two or 

 three years. Now, in the case of the eight insects I have mentioned, it is 

 only the Potato Beetle that has been with us for any length of time. I 

 therefore believe that the reason for the sudden disappearance of these 

 insects was in some way connected with the severity of our climate and 

 will continue to do so until I find, or am shown, some more plausible cause. 



