PROCEEDINGS, 1918 



13 



we could find in three visits to each of our nine observation 

 points in the province were parasitized. 



la 1916 the insect was so rare that we failed to find a single 

 example at any of our points. In 1917 a few odd colonies were 

 found at widely scattered places in the Province; and this year 

 the insect was slightly more abundant. 



So much for a glance at the control of the Forest Tent 

 Caterpillar. The next table shows the history of the Fall 

 Web worm during a period of six years of steady numerical de- 

 cline. 



TABLE 3. 



The natural control of the Fall Webworm, Hyphantria sp., 

 at Fredericton, New Brunswick, from 1912 to 1917 inclusive. 

 Showing the history each year of an average egg mass. 



1912 1913 1914 1915 1916 1917 



30 



Infertility and non-hatch 

 Larvae taken by Apanteles 48 



30 



30 



30 



30 



Birds 



Pupae taken by Exochilum 

 Pupae left to issue 



30 



34.2 233.3 253.3 266.3 268.5 206 



.1 



















1.7 1.7 1.7 1.7 1.5 2.5 



300 300 300 300 300 300 



In 1912 when the insect was fairly plentiful a reduction in 

 numbers was brought about chiefly by parasites. In succeed- 

 ing years the parasites gradually died out as the insect became 

 rare and control was maintained almost exclusively by birds. 

 By 1916 it was clear that the insect was too scarce in numbers 

 to be able to maintain its existence,and that it was rapidly van- 

 ishing from the local fauna even as the buffalo, great auk and 

 passenger pigeon had done when similarly reduced in numbers. 

 However, this process of extinction was checked by a flight of 

 moths from Nova Scotia that in a single year resulted in an 



