. Circular. Insects. The life history of our two chestnut weevils is so similar as to be practically the same for both species. There are, however, minor differences. These, as well as related nut and acorn weevils, hibernate exclusively in the larval condition and in the soil. Both make their first appearance at about the same time—with the first blooming of chestnuts—but this period may vary from late in June to July, according to locality and season, or, more properly speaking, the mean temperature. At this time the beetles are found rarely and scatteringly, and as oviposition has not been
. Circular. Insects. The life history of our two chestnut weevils is so similar as to be practically the same for both species. There are, however, minor differences. These, as well as related nut and acorn weevils, hibernate exclusively in the larval condition and in the soil. Both make their first appearance at about the same time—with the first blooming of chestnuts—but this period may vary from late in June to July, according to locality and season, or, more properly speaking, the mean temperature. At this time the beetles are found rarely and scatteringly, and as oviposition has not been observed then it is doubtful whether it begins until considerably later. What function these early arrivals fulfill is problematical. The beetles increase in number as the nuts approach maturity, or until about the middle of September or a little time before the nuts are first marketed. Then they may be seen in greater abundance, several pairs, frequently of both species, often occurring on a single bunch of burrs (fig. 8). As it requires about two weeks for the egg to develop, it is not prob- able that they are laid much earlier than when the nut begins to form. From exam- ination of many burrs gathered in the fall of 1904 by Mrf F. C. Pratt, of the Bureau of Entomology, who visited some of the principal chestnut groves of Pennsylvania and Virginia at the urgent request of groAv- ers in those States, it is deduced that the first eggs deposited are laid (seldom and very sparingly) in the soft, woolly material surrounding the forming- nut; but later they are inserted in the kernel just under the inner skins and occasionally they are deposited somewhat more deeply. In no case has the egg been found in the outer husk. Eggs are laid singly, but many are placed in a single nut, as high as 40 or more (of the smaller weevil) in imported nuts, and as many as 9 in native nuts. The larva? when hatched feed on the tissue of the growing kernels, enlarging with their own growth the cell
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