ACKNOWLEDGEMENTS 



The authors wish to express their sincere appreciation of the 

 courtesy extended ^by those friends mentioned below who have 

 assisted in this work by furnishing electrotypes, photographs and 

 drawings, thus making possible the illustration of the volume. 



The United States Department of Agriculture, through Dr. 

 L. O. Howard, Chief of the Bureau of Entomology, and Mr. 

 J. A. A. Arnold, Chief of the Division of Publications, furnished 

 a large number of electrotypes and plates. The illustrations cred- 

 ited to Dr. C. V. Riley have been secured from various sources. 



Dr. S. A. Forbes, State Entomologist of Illinois, Prof. Glen 

 W. Herrick of Cornell University, Prof. F. L. Washburn of Min- 

 nesota, Prof. H. A. Gossard of the Ohio Station, Prof. R. H. 

 Petit of Michigan Agr. College, Prof. P. J. Parrott of the New 

 York Station at Geneva, and the late Dr. John B. Smith of 

 New Jersey, all furnished several illustrations. Prof. W. E. 

 Rumsey of West Virginia made his excellent collection of photo- 

 graphs available. 



Prof. H. Garman of Kentucky, Director R. W. Thatcher of 

 the Washington Expt. Station, Prof. S. J. Hunter of the University 

 of Kansas, Prof. T. B. Symons of Maryland, Prof. H. E. Summers 

 of Iowa, Director P. H. Rolfs of the Florida Station, Dr. T. C. 

 Johnson of the Virginia Truck Station, Director J. C. Kendall of 

 the New Hampshire Station, Director S. W. Fletcher of the Vir- 

 ginia Station, Dr. W. E. Britton of Connecticut, Prof. R. I. Smith 

 of North Carolina, Dr. A. L. Quaintance of the Bureau of Ento- 

 mology, Director F. B. Mumford of the Missouri Station, and 

 Prof. C. S. Crandall of the Illinois Station, all furnished several 

 valuable illustrations. 



Dr. E. W. Berger kindly read over the copy for the chapter 

 on Citrus Fruit Insects and assisted by correcting mistaken 

 statements and offering many helpful suggestions for the im- 

 provement of the chapter. 



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