78 



HIBERNATION OF THE COTTON BOLL WEEVIL. 



Table XXXIX. — Maximum hibernation -period and percentage of survival by sections, 



1906— Continued. 



CALVERT. 



VICTORIA. 



a No estimate made. 



b Three bushels of bolls on surface and 3 bushels covered with earth. 



The longest period of hibernation occurred at Calvert among the 

 weevils placed in section 7 on October 25, the last weevil emerging 

 from tliis section being taken on July 1, 1907, During this period 

 of over eight months this weevil survived without a particle of food. 

 This may be considered as representing the maximum hibernation 

 period, and in the case of an insect producing numerous generations 

 during each season it is surprising that the hibernation period can 

 be so greatly prolonged. 



The largest average percentage of survival occurred at Victoria, 

 although the variation betw^een the three localities was not unex- 

 pectedly great. The nature of the shelter provided in each section 

 has been indicated upon page 57. A comparison of the records for 

 section 7 for Calvert and Dallas with those for the same section at 

 Victoria shows that at the last-named })lace the survival w^as four 

 times as great as in the average of Dallas and Calvert. The shelter 

 provided was as closely similar in the case of this section as in any 

 of the series, and the significant point of difference appears, there- 

 fore, to be the time when weevils were inclosed. At Dallas and Cal- 

 vert this occurred on October 24 and 25, respectively, W'hile at 

 Victoria weevils w^ere not placed in the cage until November 6. 

 Apparently, therefore, the much larger survival at Victoria was due 



