PREFACE. 



The Mexican cotton boll weevil (Anthonomus grandis Boh.) has the 

 unique record of developing in less than twenty years from a most 

 obscure species to undoubtedly one of the most important economic- 

 ally in the world. It Avas first brought to the attention of the Divi- 

 sion of Entomology as an enemy of cotton in Texas in 1894. Before 

 it had invaded more than half a dozen counties in the extreme southern 

 portion of Texas several entomologists were sent to the region in con- 

 nection with this work. Enough was soon discovered to indicate the 

 most feasible plans for avoiding damage by the pest. These original 

 plans, based upon investigations of the life history of the insect, with 

 modifications, for the most part due to climatic conditions in regions 

 quite dissimilar to the lower portion of Texas, are still the basis for 

 all that is known in combating the pest. However, at that time it 

 was necessary to pay particular attention to the immediate economic 

 phases of the problem, and a detailed study of the habits of the insect 

 was impossible. In 1902, by the aid of a special appropriation by 

 Congress, it became possible to establish a complete field laboratory 

 in the portion of Texas in which the weevil had been known to exist 

 at that time for about eight years, where a careful investigation could 

 be conducted regarding the points in the life history of the pest that 

 offered even remote chances of suggesting means of avoiding damage. 

 The results of the work at this laboratory that have been of more 

 immediate economic bearing have already been published in farmers' 

 bulletins of this Department. However, as will be seen from the fol- 

 lowing pages, a very large mass of information concerning all the 

 habits of the boll weevil has been accumulated. Not only on account 

 of the great economic importance of the problem and the demand for 

 information from numerous quarters concerning the biology of the 

 pest, but also on account of the fact that the methods followed in this 

 work have been to some extent original, and may be of use in con- 

 nection with the investigation of other insects, it is thought advisable 

 to publish a great number of the observations that have been made. 



The historical and economic features, to which reference has been 

 made elsewhere in the publications of the Division, are included to 

 bring together in convenient form practically all that is known regard- 



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