78 



HIBERNATION OF THE COTTON BOLL WEEVIL. 



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



1906— Continued. 



CALVERT. 



Section number. 



When 



installed. 



Weevils 

 started. 



Number 



basis of 

 percent- 



■ 



Date of 

 lasl 

 emer- 

 gence. 



Total 

 weevils 

 emerged. 



Percent- 

 age of 

 survival. 



1 



I'm,,. 

 Oct. L3 

 Nov. 26 



\o\ . 1 1 



Oct. 19 



Nov. 5 

 Nov. 25 

 Oct. 25 

 Oct. 31 

 Nov. L2 

 Dec. 3 



2,500 

 1. 130 

 2,500 

 2,500 



2,500 

 1,500 

 2,500 



2,500 

 Bolls. 



2, 375 



1 , 358 



2, 375 

 2,375 

 2, 375 



1. 125 



2, 375 

 2, 37.5 

 i. 375 



00 



L907. 



Juni- 12 

 ....do.... 

 May 31 

 May 30 

 Apr. 26 

 Mav 16 

 July l 



Mav 30 



June 12 



Mar. 24 



75 

 380 



116 



105 



438 



8 



3.15 



2 



27. 98 



3 



10.65 



4 



4. ^s 



5 



1.89 



ti 



25. 19 



7 



1. 42 



S 



2. 65 



9 



Is. 11 



10 











20, 430 



19, 408 





1,842 



9.49 











VICTORIA. 



1 



Oct 2.3 

 Oct. 28 

 Nov. 21 

 Oct. 25 



Nov. 14 

 Nov. 28 

 Nov. 6 

 Nov. 10 

 Nov. 21 

 Nov. 29 



2,500 



2.515 

 3.000 

 2.5IH) 

 3,000 

 1,145 

 3,000 

 3,000 

 2, 985 

 CO 



2,375 



Mav 11 



201 

 J 34 

 588 

 105 

 449 

 139 

 674 

 362 

 374 

 2 



8.46 



2 



2,389 ....do— . 

 2,850 Mav 23 



5.61 



3 



20.63 



4 



2, 375 

 2,850 



1,088 

 2,850 

 2,850 

 2, 836 



(») 



Mav 15 

 Apr. 2s 

 May 11 

 June 15 

 May 6 

 May 23 

 Mar. 4 



4.42 



5 



15.86 



(i 



12.7^ 



7 



_ ! 



8 



1". 7(1 



9 



13.19 



10 











23, 645 



22,463 





3,02S 



13.47 











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 this 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 between 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 se< tiou at 

 Victoria shows that at the last-named place the survival was Pour 

 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, while at 

 Victoria weevils were nol placed in the cage until November 6. 

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



