XU INTRODUCTION. 



went an excursion with the Society, or for his own holidays, he 

 took pleasure in collecting all the species he could find, and 

 sending them to me as a small help. But for his constantly 

 pressing me for copy, I am afraid that my sense of the in- 

 completeness of the work would have made its progress slower 

 than it has been. I saw him a few days before his death, and 

 his last words were of regret that he was not going to live to 

 see its completion. 



I have been indebted too to the pages of the " Weekly 

 Intelligencer," the " Entomologist's Monthly Magazine," and 

 the '' Entomologist " for many records, which are all acknow- 

 ledged as quoted. 



One or two, who shall not be named here, have refused to 

 give information, and I have ignored the reported captures. A 

 few others have made no reply to my request for information, 

 but I have no reason to believe that any great omission has 

 resulted therefrom. Several new lists have come to hand since 

 the volume was in type, and I shall be glad to receive others, 

 and hope to give all additional localities in an appendix to the 

 next volume. 



It must not be supposed that it is an easy matter to compile 

 a list of species that occur even in a very limited area. Mr. 

 Gardner and I have collected assiduously in the Hartlepool 

 district for very nearly fifty years, and even yet we find species 

 we had not met with before, and hear of others taking insects 

 that never came our way, so that it appears impossible to 

 exhaust even a small district. How much more difficult then 

 to complete a catalogue of an extensive area like the counties 

 of Northumberland and Durham. I have been collecting 

 material for this catalogue for quite forty years, and the 

 earliest sheets of this volume were printed off in 1895. I have 

 been adding to my own knowledgfi all this time, and lists of 

 captures have been coming in from others, yet no one knows 

 better than I do how very imperfect is our knowledge of the 

 lepidopterous fauna of the district. If two collectors like Mr. 

 Gardner and myself, who have both worked hard and regularly, 

 have not exhausted our small area in half a century, what can 



