116 THE SCOLYTID BEETLES. 



to deposit eggs. The work of excavating galleries and depositing 

 eggs is principally during June and July, but may be continued until 

 September, or later (as evidenced by the finding of young larvae in 

 October, and the same, after overwintering, the following May.) 



Fig. 71. — The eastern spruce beetle. Egg gallery and larval mines: a, Egg gallery; 6, boring dust 

 packed in gallery; c, entrance and subsequent or inner gallery; d, larval mines. (Author's Illus- 

 tration.) 



I 



The overwintered broods of larvas begin activity during the last 

 week in May and first week in June. The matured larvae begin to 

 transform to pupse and adults during the first week in June, and con- 

 tinue to do so, while the younger larvse are developing, until July or 

 later. All have evidently transformed and emerged by the middle 

 of August, or earlier. 



