138 



does the development of the weevils themselves. In several sucn 

 ways rains contribute directly or indirectlj^ to the more rapid multi- 

 plication of weevils and cause the common impression among cotton 

 planters alluded to. 



EFFECT OF WET WINTER WEATHER ON HIBERNATING WEEVILS. 



Owing to the writer's 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 unusuall}^ 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 diy. It 

 seems probable, therefore, that as many weevils perished from fre- 

 quent wetting as from exposure to the cold. The winter of 1903-4 

 was generally dry and the number of weevils hibernating successfully 

 was larger than in the previous year. 



EFFECT 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 Kiver covered many of the cotton fields 

 along its coui^se. The fields in which especial study was made w^ere 

 wholly submerged from one to several da}- s. 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 IT. 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, in 

 the vicinity of Victoria, 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 contained unin- 

 jured larvse and pupae. Naturally eggs and larvae found in squares 

 upon the plants, even though under water for some time, escaped 



