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upon young cotton in the spring it seems not improbable that during 

 favorable seasons something like this percentage of the weevils find- 

 ing favorable shelter will live. Of course, the percentage finding 

 favorable shelter will be extremely variable, and it is in reducing the 

 number and accessibility of favorable locations that the cotton planter 

 has one of his very best opportunities to effect the destruction of a 

 multitude of weevils, and thus greatly reduce the number which will 

 emerge from hibernation and attack the crop of the following season. 

 With shelter removed, cold and changeable weather will inevitably 

 destroy many, and, in fact, most, of the weevils which would other- 

 wise survive. 



SEASONAL HISTORY. 

 EMERGENCE FROM HIBERNATION. 



Emergence depends largely, as has been already shown, upon the 

 mean average temperature prevailing. The presence of food does 

 not seem to affect it. In the season of 1903 for one month preceding 

 the emergence of weevils at Victoria the mean average temperature 

 was 65.4° F. For the first two weeks of April it averaged 68.4° F. 

 Weevils left their winter quarters from the middle to the last of 

 April. While the mean average temperature for May was nearly 3° 

 lower than the temperature prevailing at the time of emergence, 

 weevils remained actively at work in the fields. In the fall also 

 weevils remained at work at a lower temperature than that which 

 seems to be necessary to draw them from their winter quarters. The 

 reason for this fact is not apparent, but it is certain that once having 

 left hibernation weevils will remain active at considerably lower tem- 

 peratures. If the temperature becomes too low they remain quiet 

 without taking food for long periods of time. If taken from their 

 winter quarters weevils will be found active at ordinary day tempera- 

 tures long before they would normally venture from their hiding 

 places of their own accord. Weevils thus removed have been kept 

 for a month without food or water, and they then assumed their 

 normal activities when food was supplied to them. 



After considerable search at San Diego in the spring of 1895, on 

 April 27 Mr. Schwarz found the first specimens working upon seppa 

 plants from roots which were then 2 years old. As the weevils first 

 appeared in that locality in August, 1894, the number of hibernat- 

 ing weevils could not have been as great as in succeeding years, 

 and consequently in the spring of 1895 hibernated specimens were 

 "exceedingly rare." At Yictoria, Tex., in the spring of 1902, Mr. 

 Schwarz found the first weevils working upon volunteer plants on April 

 15. In the same locality the writer found, in 1903, that weevils left 

 their winter quarters between April 10 and May 1. Evidence was 

 found indicating that in some fields they began to move as early as 

 March 28. At Calvert, Tex., also in 1903, Mr, Harris found the first 



