Introduction 
Vll 
All specific endings have been modified to agree with the suggestions 
made by Blackwelder 1940, Journal of the Washington Academy of Sciences 
31: 135-140. There are certain disadvantages inherent in this method, but 
it seems to the writer that these limitations are outweighed by the ad¬ 
vantages of this system. We are confronted by so many coined words that 
can have no sex that it seems better to use this system and disregard appar¬ 
ent 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. We will appreciate it very much if our attention is directed 
to all such mistakes. It is especially easy to overlook local lists when pub¬ 
lished in the proceedings of local natural history societies, references to 
species of economic importance when published in scientific agricultural 
journals, references to vectors of plant diseases when published in phyto- 
pathological journals, and many other 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 changes in the nomen¬ 
clature adopted in this catalogue should not 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. 
Z. P. Metcalf 
AND 
Clyde F. Smith 
Raleigh, North Carolina 
June 1957 
