PREFACE. 



When six years since this great work, after twenty years 

 of preparation, was completed, the disappointment to Lepi- 

 dopterists that it contained no index of species was intense 

 and universal. The want of this made it to all save a com- 

 parative few a sealed book, as the index to the genera afforded 

 little aid, owing to many changes in the generic position of 

 species and the adoption of new or long-forgotten genera as 

 well as the placing thereof according to the compiler's own 

 ideas. For in this almost everyone has his own various, 

 original, adopted, or modified views ; generic division being 

 merely artificial, only a matter of convenience for grouping, 

 not abiding, continually liable to be changed and continually 

 being changed : consequently not only of minor importance, 

 but when carried to extremes a great evil, a hindrance to the 

 student, an actual bar to the beginner. It is only by the 

 specific name that we know the insect ; with the knowledge 

 of that the rest is attainable. Mr. Kirby mentions in his 

 preface that on the completion of vols. II., III., IV., and 

 y. there will be full indices to the whole, but as these are 

 all yet to be published, and, alas ! we are human with but 

 limited stay here ; and as it has taken twenty yeai's to com- 

 plete the present volume, it may be a long time until the 

 other four are finished and with them the indices. I had 



