CANKER-WOKM. 103 



doubt that the Canker-worm had been theagent of the mischief, though 

 I had never happened to have an opportunity to observe the habits of 

 this insect where it prevailed to so large an extent. 



The winter of 1870-71 was equable and mild. There was an unusual 

 fall of snow for this section of the country, and the ground was not 

 deeply frozen. The first week of March was remarkably warm, and 

 the remnant of snow disappeared, except where it had been deeply 

 drifted. 



Calling the canker-worms to mind, I suspected tha-. under these cir- 

 cumstances the moths would be moving early in the season. 



March 7. — Upon visiting the infested orchard late in the afternoon, 

 I found many of the male moths flying about the trunks of the trees 

 and alighting upon them. Not a female was, as yet, to be seen. But 

 upon looking amongst the dead grass and leaves at the foot of the treep, 

 I found a considerable number of the wingless females, inactive and 

 apparently torpid. 



Kemaining in the orchard till it began to get dark, I noticed a 

 striking Increase in the activity of the moths of both sexes. The ft males 

 could now be seen emerging from their concealment, and crawling 

 eagerly up the trunks of the nearest trees attended by, and often paired 

 with, their fluttering mates. Visiting the orchard agam the same 

 evening after nine o'clock, with a lantern, I found the moths still tra- 

 veling up the trunks of the trees and out upun the larger branches, 

 but there did not seem to be that universal and restless activity which 

 prevailed earlier in the evening. From this and subsequent observa- 

 tions, I conclude that these insects are crepuscular in their habits, 

 rather than strictly nocturnal. 



March 8. — Yisited the orchard in the forenoon. Only here and 

 there a solitary moth could be seen. But upon looking under the dead 

 leaves and grass around the foot of the trees, and under the loose l)ark 

 on the trunk and larger branches, the insects of both sexes, but espe- 

 cially the wingless females, were found, often crowded together torpid 

 and motionless, and waiting for the return of night to resume their 

 activity. Fifteen or twenty insects could be sometimes counted under 

 one f»f the larger scales. 



March 9. — Yesterday afternoon there occurred a violent thunder- 

 storm with occasional heavy showers, which settled into a steady rain 

 in the evening, and continued till near midnight. It grew cold in the 

 night, and to-day there has been a sprinkling of snow. I was curious 

 to see how so sudden and severe a change of the weather had affected 



