Introduction 
vii 
can have no sex that it seems better to use this system and disregard ap- 
parent violations of Latin and Greek grammar. Where the sex 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 elim- 
inate all errors. The author will appreciate it very much if his attention is 
directed to all such mistakes. It is especially easy to overlook local lists 
when published in the proceedings of local natural history societies, refer- 
ences to species of economic importance when published in scientific 
agricultural journals, references to vectors of plant diseases when pub- 
lished in phytopathological journals, and many other references of a 
similar nature. It will be very much appreciated if authors will send me 
reprints of all articles dealing with the Homoptera Auchenorhyncha so 
that this material may be included in future catalogues to make them as 
complete as possible. Also it would seem to the author that changes in 
the nomenclature adopted in this catalogue should not be made in the 
future without a full explanation. 
All literature available to the writer before August 1, 1955 has been 
included in this catalogue. 
Z. P. Metcalf 
Raleigh, North Carolina 
August 1955 
