. An annotated list of the important North American forest insects. Forest insects. 12 Bulletin 449 found collected below the lower bands. Apparently they were attempting to crawl up the trunks in order to reach the terminals. Up to June 15, none of the banded trees were infested. By July 21, however, three weeviled shoots were found on the plot. It is possible that the weevils may have flown to the tips; but it is more likely that, during a cold rainy period in the latter part of June, the tanglefoot may have become glazed sufficiently to permit its being crossed by the weevils. Of the thirty
. An annotated list of the important North American forest insects. Forest insects. 12 Bulletin 449 found collected below the lower bands. Apparently they were attempting to crawl up the trunks in order to reach the terminals. Up to June 15, none of the banded trees were infested. By July 21, however, three weeviled shoots were found on the plot. It is possible that the weevils may have flown to the tips; but it is more likely that, during a cold rainy period in the latter part of June, the tanglefoot may have become glazed sufficiently to permit its being crossed by the weevils. Of the thirty unbanded trees on this plot, eleven were weeviled — an unusually large proportion for a single season. From this ex- periment it appears probable that, although the white-pine weevil is, under certain con- ditions, a good flier, it usually reaches the terminal shoot by creeping up the trvnik of the tree. In the spring, after having fed on the trees for a day or two, the beetles mate. During the entire oviposition period they are usually found in pairs, a male nearly always being found wherever a female is ovipositing. It appears, however, that they occasionally mate in the autumn previous to the period of ovi- position. The possibility of this was first indicated by an occurrence in one of the experimental cages placed over uninfested white-pine saplings near Ithaca. In the spring, before any weevils had been introduced, a female appeared, presumably from the litter at the base of the trees, and promptly began to oviposit. She laid 115 eggs in one shoot and did not move to any other during the entire period. The eggs proved fertile and nearly all of them hatched. No other weevil was in the cage during any part of the season; therefore, the only possible explanation is that either the weevils can reproduce parthe- nogenetically, or fertilization in this instance had taken place during the preceding year. The latter supposition seems, on the face of it, the more probable. Furt
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