Preface. 
an a ee 
ft is now twenty years since the completion of Doubleday, Hew- 
itson, and Westwood’s “Genera of Diurnal Lepidoptera”, a work which 
included a complete Catalogue of all the species then known. The 
great advance which has since been made in our knowledge of this 
group, has rendered necessary another Catalogue brought down to the 
present date, a want which has hitherto been only partially supplied 
by various monographs and catalogues of limited extent. 
Although full materials for a natural arrangement of all the spe- 
cies could not be obtained, it was ‘thought better to attempt some 
kind of arrangement, however imperfect, than to place the species al- 
phabetically. Those species which are entirely unclassed will be found 
at the end of their genus, either under a line, or in alphabetical order. 
The unclassed Hesperide are included under Pamphila. The fol- 
lowing genera, among others, must be understood to be only provisio- 
nally retained in their entirety: Acrwa, Aaiocerses, Plebeius, Thecla, 
Pieris, and Papilio. It is to be regretted that Mr. Butler’s revision 
of the genera of Prerinc was published too late to be made use of. 
The great length to which this work has extended, necessarily 
precludes the addition of a Bibliography, but a list of authors’ names 
has been drawn up, which will to some extent compensate for the 
omission. Those authors whose works have been examined througout 
are marked thus (*), and those a part only of whose works were ac- 
cessible, thus: (+). 
Some slight errors in the dates of publication of certain works 
which affect the synonymy, will be found corrected in the Appendix, 
and some typographical errors in the Index; but it has not been 
thought necessary to add a list of errata. 
A repeated number followed by a letter indicates a doubt as to 
whether the second species may not be a synonym or variety of the 
first. Intercalated species are indicated by a repeated number followed 
by “bis”, and, in the Appendix, also by the signs (*+) &c. 
