giving latinized names to varieties that in the past have been 

 designated by Arabic letters, Greek letters, numbers, or other 

 designations. All varieties are catalogued, however, under the 

 first designation, regardless of its form. Some of these varieties 

 may prove to be valid species with further study, and then may be 

 given latinized designations. 



Primary homonyms of species have been replaced by nominee 

 nova; secondary homonyms have been restored to their original 

 names if the homonymy has been relieved by moving one or the 

 other, or both, species to other genera. 



All specific endings have been modified to agree with the sugges- 

 tions made by Blackwelder 1940, Journal of the Washington 

 Academy of Sciences 31: 135-140. There are certain disad- 

 vantages inherent in this method, but it seems to the writer that 

 these limitations are outweighed by the advantages. We are 

 confronted by so many coined words that can have no gender, it 

 seems better to use this system and disregard apparent violations 

 of Latin and Greek grammar. Where the gender of generic names 

 can be determined, the appropriate adjustments are made in the 

 specific names. 



In a detailed catalogue such as this it is practically impossible 

 to eliminate all errors. We will appreciate it very much if our 

 attention is directed to all such mistakes. It is especially easy to 

 overlook lists published in the proceedings of local natural history 

 societies, references to species of economic importance published 

 in scientific agricultural journals, references to vectors of plant 

 diseases published in phytopathological journals, and references of 

 a similar nature. It will be very much appreciated if authors 

 will send us reprints of all articles dealing with the Homoptera. 

 Also, it would seem that no changes in the nomenclature adopted 

 in this catalogue should be made in the future without a full 

 explanation. 



All literature available to the writer before December 31, 1955, 

 has been included in this catalogue. 



The present catalogue of the Family Euscelidae is the tenth part 

 of the Cicadelloidea. This was virtually complete at the time of the 

 death of Dr. Z. P. Metcalf on January 5, 1956. It was completed 

 with the aid of Miss Virginia Wade, research analyst, North 

 Carolina State University, who worked with Dr. Metcalf for seven 

 years, and the technical advice of Dr. David A. Young, North 

 Carolina State University and Dr. W. H. Anderson, Insect Identi- 

 fication and Parasite Introduction Research Branch, Entomology 

 Research Division, Agricultural Research Service, U. S. Depart- 

 Ill 



