LETTER OF TRANSMITTAL. 



U. S. Department of Agriculture, 



Bureau of Entomology, 

 Washington, D. C, August 20, 1907. 



Sir: I have the honor to transmit herewith the manuscript of a 

 paper, by Dr. W. E. Hinds of this Bureau, entitled "Some Factors 

 in the Natural Control of the Mexican Cotton Boll Weevil." It deals 

 especially with three important factors of natural control, concerning 

 which our knowledge has been largely extended through the cotton 

 boll weevil investigations of the Bureau during the season of 1906. 

 These factors are: Temperature and moisture conditions, predaceous 

 and parasitic enemies, and food supply. 



In view of the fact that the boll weevil is not a passing pest, but 

 rather an enemy with which the cotton grower must reckon each year, 

 it is evident that our knowledge of every factor affecting favorably or 

 unfavorably its development and attack must be made as complete 

 as possible. While it may not be possible to increase the effectiveness 

 of some of these factors, there is reason to believe that with our more 

 exact knowledge of the nature of their effect upon the weevil and 

 of the conditions under which they produce most beneficial results 

 others may be utilized far more than has been done heretofore, thus 

 lessening very materially the damage annually inflicted by the weevil 

 at little, if any, expense. 



This study of the natural control of the boll weevil is probably 

 based upon one of the most extensive series of definite examinations 

 and records which has ever been made in economic entomology. The 

 paper reporting this work is therefore based upon a large amount of 

 statistical data. This has been tabulated with a view to as much 

 condensation as possible without destroying the value and signifi- 

 cance of the records. The illustrations accompanying the manu- 

 script are necessary for the best understanding of the text. I recom- 

 mend the publication of this report as Bulletin No. 74 of the Bureau 

 of Entomology. 



Respectfully, 



Hon. James Wilson, 



Secretary of Agriculture. 



II . Chittenden, 

 Acting Ch ief of Burea u . 



