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1920] Herrick: Hibernation of Insects 107 



happen in the latitude of Washington, D. C. Folsom'^ says: "In 

 central IlHnois we have only one annual generation of this insect, 

 as seems to be the rule elsewhere," and later he also says: " In a 

 warmer latitude than this there might very well be a second gen- 

 eration of beetles, to hibernate and lay eggs the following spring." 

 It seems to me that our observations and breeding experi- 

 ments show fairly conclusively that the clover leaf-weevil may 

 survive favorable winters and become active enough in the 

 spring to deposit eggs thus producing exceptionally a second 

 generation in central New York. It will be recalled that Novem- 

 ber of 1918 "was warm and pleasant for the most part" and that 

 "December was unusually mild with an average excess of 

 warmth of about four and one-half degrees." These conditions 

 may well have given opportunity for many of the larvae to have 

 reached maturity in the fall and to have transformed to beetles 

 which found favorable weather conditions, during January, Feb- 

 ruary and March. Thus they were able to pass the winter with- 

 out impaired vitality and deposited eggs in the spring. Moreover, 

 these observations, it seems to me, indicate strongly that farther 

 south where the winter conditions are habitually more favorable, 

 there may be normally a second generation of the weevils. 



REFERENCEvS. 



1. Pierce. W. D. Proc. of the Class to Study Ent. of Dis., Hyg. and San. 7th 



Sec, 1918. 



2, 3, 5. Folsom, J. W. 111. Agr. Expt. Stat., Bull.. 134, pp. 155-164, 1909. 

 4. Riley, C. V. Rept. U. S. Dept. Agr., 1881-82, p. 176, 1883. 



