A debt of gratitude is due to Dr. C. H. Turner of Sum- 

 ner High School of this city for critically reading the 

 manuscript, and to Dr. L. O. Howard and the various spe- 

 cialists connected with the United States Department of 

 Agriculture and the Smithsonian Institution whose names 

 appear in brackets throughout this work we desire to ex- 

 press our thanks for the identification of the various insects, 

 and especially is our gratitude due to Mr. S. A. Rohwer for 

 much taxonomic information. 



PHIL RAU, 

 NELLIE RAU. 

 SAINT Louis, Mo. 

 November 29, 1917. 



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