The paper includes all of the species definitely known 

 and those that are at all likely to occur within our terri- 

 tory. It is only a beginning, however, and without doubt 

 many new and interesting forms are yet to be discovered 

 and described. 



To bring together in convenient form the widely 

 scattered descriptions, I have given a rather full descrip- 

 tion of each species that occurs in this region. I have 

 drawn freely upon the original published sources, where 

 these have been satisfactory, and have abbreviated, ampli- 

 fied or otherwise modified these as the conditions required, 

 after examining, where possible, large series of specimens 

 many of which were types and paratypes. In a few cases 

 actual specimens were not available and in these the de- 

 scription is drawn up from the original to conform with 

 the others. The keys are intended only for the forms known 

 to inhabit the Southern United States. 



ACKNOWLEDGMENTS 



The writer wishes to acknowledge here his great in- 

 debtedness to Prof. Herbert Osborn, of the Ohio State 

 University, under whose supervision and direction this 

 work has been done. Credit is due him for constant advice 

 and assistance and especially for the placing of many of his 

 records and his entire private library and collections, the 

 latter containing many type specimens, at my disposal. To 

 Prof. R. W. Earned, he is much indebted for arrangement 

 of the work in such a manner as to make varied and repre- 

 sentative collecting possible. To Dr. E. D. Ball and W. L. 

 McAtee the writer wishes to express appreciation for the 

 kind courtesies and help they have extended him in the 

 examination of type and other material. Mr. George Ainslie 

 has kindly given the writer some valuable distribution 

 records from his Tennessee and Florida collected material. 

 The writer also wishes to thank Dr. Raymond C. Osburn 

 and W. L. McAtee for their kindness in carefully reading 

 and criticizing the manuscript. L. Chester Marston, Jr., of 

 the Delaware Agricultural Experiment Station made figures 

 9, 17, 18 and 20. To these and all others who in any way 

 have assisted him in the completion of this work, the writer 

 hereby expresses his sincere thanks. 



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