THE CANKER-WORMS 7 



greatest distance to which they may be blown in this manner does not 

 seem to have been demonstrated, but they are doubtless blown at least 

 from tree to tree. (2) The larger larvse also suspend themselves by 

 threads and some of them are often caught on passing vehicles and 

 transported to new localities. (3) The &gg masses, particularly of 

 the fall species, which winters in this condition, are frequently car- 



Fig. 1. — Distribution of the fall cankerworm. 



ried to uninf ested territory on nursery stock. In 1911 egg masses of 

 the fall cankerworm were found in British Columbia on nursery 

 stock imported from the United States ($4). The clusters of eggs 

 are easily overlooked, and doubtless many of them have been trans- 

 ported to other localities where the cankerworm had been hitherto 

 unknown. 



