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tlie life cj^cles of certain species. For example, the larger chestnut 

 weevil and the smaller chestnut weevil look alike, but they are de- 

 cidedly unlike in their development. The grubs of the larger weevil 

 begin to leave the nuts at about the timei the nuts drop. They enter 

 the soil to a depth of several inches and fashion smooth-walled cells 

 in which they remain unchanged until the following summer. Dui'ing 

 June and July they transform to pupae, and soon afterward to 

 adults. In August they issue from the ground and seek the trees 

 where they collect around the burs and begin to deposit eggs soon 

 after the nut kernels start to form. This life cycle is continued year 

 after year. To forestall starvation of the race in case of entire failure 

 for a year of the chestnut crop, a few individuals cirry over tlie 

 second winter in the ground and then issue as beetles along with the 

 one-year-old specimens. It is probable that a small per cent of the 

 insects may remain in the soil over three winters. Thus does nature 

 by unique arrangements safeguard the lives of even the very small 

 creatures. 



The life cycle of the lesser weevil is quite different. The larvae 

 of this species leave the nuts somewhat later in the autumn than do 

 those of the larger weevil. Like them, they enter the ground and pass 

 the first winter unchanged. The grub stage is continued throughout 

 the summer, but late in autumn, after the beetles of the larger spe- 

 cies have been on the trees for some weeks and deposited most of their 

 eggs, the larvae of the smaller species transform to adults. Instead 

 of coming from the ground, however, they remain in their earthen 

 cells throughout the winter. The next spring, prior to the blooming 

 of the chestnut-trees, they emerge from the ground and soon there- 

 after collect in large numbers on the male catkins of the chestnuts. At 

 tliis time very little feeding is done and the sex instinct does not mani- 

 fest itself. As the time approaches for the nuts to mature, however, 

 the beetles begin to feed and pair and soon thereafter to lay their 

 eggs in the ripening nuts. Most of the eggs are deposited directly 

 into the nuts after the burs begin to open. In the case of the larger 

 weevils the beetles are present only about three months of the year. 

 Those of the lesser species, however, are perpetually present, those of 

 the younger generation reaching the adult stage in the groimd before 

 those of the previous generation have finished laying their eggs in the 

 ripening nuts. As with the larger species, a few of the smaller 

 weevils carrv as larvae for several years to tide over possible fail- 



