Introduction 
V 
this series and since about three-fourths of the catalogues are in manu¬ 
script, it was not deemed wise to make this change at this time. 
FORM OF THE PRESENT CATALOGUE 
This catalogue follows the general form of the present series. The family 
is divided into genera which are arranged in as nearly a phylogenetic order 
as our present knowledge will permit. The species are arranged under the 
genera in alphabetic sequence. Titles of books are not abbreviated but are 
condensed if they are unduly long. The abbreviations of journal references 
follow in general the scheme proposed in the World List of Scientific Pe¬ 
riodicals with minor exceptions, the chief difference being that the names 
of countries, states, cities and other geographical units are not abbreviated. 
A few references are listed under their titles rather than under the abbrevia¬ 
tions of the journals in which they were published, because in these cases 
the titles are usually better known than the journals, for example. Van 
Duzee 1917 Catalogue of Hemiptera of America North of Mexico not Techn. 
Bull. California Agr. Exp. Sta. Ent. 2. If the journal has been published in 
series the abbreviation of the journal is followed by a series number or by 
such an abbreviation as n.s. (new series), o.s. (old series), n.f. (neue Folge), 
or the like. This is followed by a note indicating the nature of the reference. 
The notes which follow the references are generally self explanatory, 
but three points may be mentioned here. Such notations as ‘‘[described],” 
“[notes],” “[key],” and the like are intended to be suggestive rather than 
precise or exclusive. The notation “[error]” means not accepted in this 
catalogue. Usually the latest published synonymy is accepted, but not 
always. The other notation “[comparative note]” is used to designate those 
references, often of the greatest taxonomic significance, in which two ge¬ 
neric, specific or other groups are compared. All references have been checked 
against the original save those marked with an asterisk (*), which have 
been accepted from reliable sources. Every effort has been made to have 
the references full and complete and to give an indication of the character 
of the data contained. Where the writer knows that reprints have been 
issued with different pagination, this is indicated in parentheses following 
the page numbers of the original. In a few cases, where the matter has 
been reprinted under a different title with different pagination, separate 
references are given. Where authentic editions have been republished these 
have been indicated by separate references. Genera established without 
included species have been dated from their original description, with their 
type fixation dated at the earliest time the action can logically be inter¬ 
preted to have occurred. Original spellings have been retained in all cases, 
except obvious typographical errors. Typographical errors are indicated 
by placing “[sic]” after the misspelled name. This is not for the purpose of 
