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EFFECT OF WET WINTER WEATHER ON HIBERNATING WEEVILS. 



Owing to the writers' absence from Victoria during the winter 

 months, observations could not be made directly or immediately upon 

 this point. It was found, however, that all weevils in hibernation 

 tests which passed the winter successfully had been kept dry. The 

 winter of 1902-3 was unusually wet at Victoria, and the number of 

 hibernated weevils which were to be found on early cotton plants was 

 noticeably less than during previous seasons which had been dry. It 

 seems probable, therefore, that as many weevils perish from frequent 

 wetting as from exposure to the cold. 



EFFECTS OF OVERFLOWS IN FIELDS. 



Unusually favorable conditions for these observations were obtained 

 at Victoria in the season of 1903. During the latter part of February 

 an overflow of the Guadalupe River covered niany of the cotton fields 

 along its course. The fields in which especial study was made were 

 wholly submerged from one to several days. Cotton was planted in 

 some of these fields between March 15 and 17. Owing to cold 

 weather the growth of the plants was delayed and squaring did not 

 begin until between May 10 and 17. Immediately after this date it 

 was found that weevils were present and at work, and fallen squares 

 were first found about May 23. From a study of this field it became 

 apparent that the overflow had caused a considerably less decrease 

 than had been anticipated in the number of hibernating weevils. 

 Possibly the fact that the winter of 1902-3 had been exceptionally 

 rainy may account for the lack of contrast in weevil abundance in 

 overflowed fields and those which did not suffer in this way since, as 

 has already been noted, hibernated weevils were unusually scarce, 

 even on uplands. 



Another period of high water occurred during the last of June and 

 the first of July and gave a convenient opportunity to note its effect 

 upon active weevils. Many fields were partially and some wholly 

 submerged. This condition lasted for several days. Examination 

 made after the recession of the water showed that many fallen 

 squares which had certainly been in the water for some time con- 

 tained uninjured larvae and pupa?. Naturally eggs and larvae 

 found in squares upon the plants, even though under water for some 

 time, escaped unharmed. Weevils were working normally upon the 

 plants. No diminution in their numbers could be seen and it was 

 apparent that the overflow caused no check either to the develop- 

 ment of the immature stages or to the activity of the adults. These 

 observations emphasize the fact that the weevil can not be drowned 

 out. 



