LETTER OF TRANSMITTAL. 



U. S. Department of Agriculture, 

 Bureau of Entomology, 



Washington, D. C, July 29, 1907. 

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

 "Studies of Parasites of the Cotton Boll Weevil," by Mr. W. Dwight 

 Pierce, a special field agent of tins Bureau engaged in cotton boll 

 weevil investigations. Some of the preliminary results of these 

 studies were published as Bulletin Xo. 63, Part II, of the Bureau of 

 Entomology, under the title "Notes on the Biology of Certain Weevils 

 Related to the Cotton Boll Weevil." The boll weevil in the United 

 States is now known to be attacked by several species of parasitic 

 insects. These have not been introduced with the boll weevil from 

 the country from which the latter spread, but they have been here 

 for years as parasites of other species of weevils occurring in the 

 territory now infested by the boll weevil. The present manuscript 

 contains a record of investigations of these parasites and deals 

 especially with the possible practical applications which may be 

 made of the results gained. I recommend its publication as Bulletin 

 Xo. 73 of this Bureau. 



Respectfully. L. O. Howard, 



Entom ologist a nd Chief of B u rea u . 

 Hon. James Wilson, 



Secretary of Agriculture. 



