LETTER OF TRANSMITTAL. 



United States Department of Agriculture, 



Bureau of Entomology, 



Washington, D. C, October 5, 1912. 

 Sm: I have the honor to transmit herewith for pubhcation as 

 Technical Series No. 12, of this bureau, nine papers deahng with the 

 classification, description, or habits and life history of various insects 

 belonging to groups of economic miportance. 



These papers, prepared by different employees of the bureau and 

 published separately during the years 1906-1908, are as follows: 

 Catalogue of Recently Described Coccidse, by J. G. Sanders; Habits 

 and Life Histories of some Flies of the Family Tabanidse, by James 

 S. Hine; A Contribution to our Knowledge of the Thysanoptera of 

 California, by Dudley Moulton; New Genera and Species of Aphe- 

 luiinae, with a Revised Table of Genera, by L. O. Howard; The More 

 Important Aleyrodidae Infesting Economic Plants, wdth Description 

 of a New Species Infesting the Orange, by A. L. Quaintance; A Record 

 of Results from Rearings and Dissections of Tachinidse, by Charles 

 H. T. Townsend; The Orange Thrips, by Dudley Moulton; Bio- 

 logical Studies on Three Species of Aphididse, by John June Davis; 

 A New Genus of Aleyrodidge, with Remarks on Aleyrodes nubifera 

 Berger and Aleyrodes citri Riley and Howard, by A. L. Quaintance. 

 Respectfully, 



L. O. Howard, 

 Entomologist and Chief of Bureau. 

 Hon. James Wilson, 



Secretary of Agriculture. 



