. An annotated list of the important North American forest insects. Forest insects. conditions existing at Ithaca during the summer of 1915. This length of time would vary somewhat from season to season, since the length of the developmental period is influenced greatly by weather conditions. ACTIVITIES OF THE YOUNG ADULTS After the beetles transform, they remain in the pupal cells for a period of from two weeks to a month. Final!}- they gnaw their way to the outside. Emergence of the young adults continues from the middle of July through September and into October. After they emerge, the weev
. An annotated list of the important North American forest insects. Forest insects. conditions existing at Ithaca during the summer of 1915. This length of time would vary somewhat from season to season, since the length of the developmental period is influenced greatly by weather conditions. ACTIVITIES OF THE YOUNG ADULTS After the beetles transform, they remain in the pupal cells for a period of from two weeks to a month. Final!}- they gnaw their way to the outside. Emergence of the young adults continues from the middle of July through September and into October. After they emerge, the weevils feed for a short time on the newly formed buds or the young growth of pines. After this feeding period they seek a place in which to hibernate dur- ing the winter, although the weather at the time may still be warm. Mention has already been made of an instance in which mating probably took place in the fall before hibernation. In order to determine whether or not this is possible, more than a hundred newly emerged weevils were placed in a cage in the laboratory on August 3. They were fed on fresh pine tips, which they ate voraciously at first. After a few days they be- came restless and began wander- ing around as if looking for a place in which to hibernate, but, since there was no litter in the cage, they were forced to keep in sight. They were kept in cages under observation until the last one died, in November. During this period but one pair copu- lated, and they only once. This indicates that occasionally the weevils may mate during the fall in which they emerge, but that such mating is rare. Hopkins (1911) states that when the female weevils emerge their ovaries are undeveloped and they could not possibly produce eggs in less than a month after appearing as adults. If they laid eggs so late in the season as this would necessitate, the larvae would not be half grown by cold weather and could be found in the shoots during the winter. Never have living eggs, larvae, or
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Keywords: ., bookauthorhopkinsadandrewdelmar, bookcentury1900, bookdecade1900
