Page:The white-pine weevil (IA whitepineweevil290hopk).pdf/8

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eggs in punctures in the bark of the shoot of the previous year's growth, placing one or two eggs in a pit or cavity in the inner bark made by the beak of the mother beetle.

Fig. 2.—White-pine weevil: Newly hatched larvæ at work in vigorous terminal shoot of white pine. (Author's illustration.)

In from six to ten days the eggs begin to hatch into small white grubs (larvæ), which at first are usually found in large numbers feeding upon the inner bark and cambium (see fig. 2). They usually work downward and sometimes extend their work into the bark of the 2-year-old stem and base of the branches. By the time the larvæ have completed their development (fig. 1, b) they are greatly reduced in numbers by natural enemies and other causes. The survivors burrow into the wood or pith of the terminal and excavate individual transformation cells, which they line and cover with excelsior-like borings. In these cells they transform to pupæ (see fig. 1, c) and adults, and during July and August of the same year, when the adults are fully matured, they bore their way out and seek suitable places in which to pass the winter.

LONG LIFE OF THE ADULT.

From recorded observations on some species of Pissodes or bark weevils by investigators in Europe, and on representatives of other allied forms in Europe and in this country, it appears that an individual adult may live two or three years and will deposit eggs each year.

SEASONAL HISTORY.

The beetles are active from about the 1st to the 15th of May or laters, depending on local conditions and weather. Eggs are evidently deposited during the principal activity of the adults, possibly during the greater part of the month of May. The