DESTRUCTION OF COTTON FORMS. 71 



seems that the presence or absence of a weevil stage has little, if any- 

 thing, to do with the retention by the plant of a portion of its surplus 

 fruit, but that the abundance of weevils in proportion to then food 

 supply may be largely responsible for the variations which appear in 

 the percentage of these dried, hanging bolls which contain some 

 weevil stage. 



In Table XVI B, among the hanging dried squares, nearly 59 per 

 cent of these examined contained some weevil stage. In this case 

 there were found an average of but 1.01 stages per square. The per- 

 centage containing weevil stages varies somewhat, as it did in the case 

 of dried bolls, but the variations are not exactly parallel. One 

 reason for this apparent lack of agreement may be found in the fact 

 that weevils show considerable preference for squares, and therefore 

 attack them to a much larger extent than they do the small bolls. 

 Among the bolls an average of 24.6 per cent contained some stage of 

 the weevil, while among the dried squares there were 58.8 per cent. 



In Table XVI C, fallen bolls, it appears that an average of only 

 about 18 per cent contained some weevil stage. In this case there 

 were found 1.106 weevil stages for each boll found to contain any. 

 Examinations in three localities failed to reveal any weevil stage in a 

 total of 380 bolls. Two of these examinations were made at Victoria 

 in June before weevils had become sufficiently abundant to attack 

 bolls to any extent. The third case was at San Antonio, where, as is 

 indicated by observations in the other classes of forms, the infestation 

 was comparatively light. It is probable, however, that a more 

 extensive examination would have revealed some weevil stages in 

 fallen bolls at San Antonio. 



In Table XVI D, fallen squares, it is shown that slightly over 60 

 per cent contained some weevil stage. In this very large series of 

 examinations there were but 1.05 stages for each square containing 

 any. As would naturally be expected, there is not quite so wide a 

 range between the extremes in the percentage of total squares which 

 were found to contain a weevil stage as in other classes of forms. 

 The importance of fallen squares, as compared with other classes of 

 infested fruit, is shown by the fact that, in the 36,354 fallen squares 

 examined, were found 22,169 weevil stages; whereas, in the 40,166 

 forms in the other three classes for Texas, there were but 11,666 

 weevil stages. While 60.7 per cent of the fallen squares were found 

 to contain some stage of the weevil, an average of the three other 

 classes of forms showed stages in but 26 per cent. The special signif- 

 icance of these comparisons, from the standpoint of natural control 

 of the weevil, may be appreciated when it is considered thai the total 

 mortality in fallen squares is much greater than in any other class of 

 forms. 



