INTRODUCTION. V. 



corrected. The remainder of the manuscript was just as it 

 had come from Mr. Robson's pen, a loose sheet being devoted to 

 each species. Mr. Bankes, as stated in his letter to the Council, 

 had written critical notes upon the whole of the manuscript 

 prepared for this part of the catalogue during Mr. Robson's life- 

 time, but these the latter did not live to use. These notes, 

 which were very numerous and in some cases of considerable 

 length, it was necessary to incorporate with the manuscript. 

 This has been done to the best of my ability, full justice being 

 done to Mr. Bankes, and at the same time interfering as little 

 as possible with the original manuscript, which Mr. Bankes 

 himself was always careful to do. In many instances the in- 

 clusion of these notes entailed the entire re- writing of the sheets 

 to which they referred. 



As previously stated, neither manuscript nor records for the 

 plume moths ^Pterophorids) were forthcoming at the time of 

 Mr. liobson's death, and I am therefore responsible for this 

 little group. 



A short supplement appears at the end containing additional 

 species to record, species requiring to be struck out, notes upon, 

 and additional records for, many species mentioned in previous 

 portions of the catalogue. In connection with the latter I have 

 to thank Mr. J. W. H. Harrison, late of Birtley, for a list of 

 species occurring in that neighbourhood, as well as for notes of 

 a few species found in other parts of our two counties. 



I am much indebted to my friend Dr. C. 0. Trechmann for 

 compiling the index and errata, and have also to thank him for 

 kind and willing assistance during the progress of this work ; 

 he went over every sheet before it was sent to the printer, and 

 assisted in correcting every sheet of proof which came from the 

 printer. His advice upon any doubtful matter was also always 

 at my service. 



I have also to thank your Curator, Mr. E. Leonard Gill, for 

 his ever ready help in correcting proof and looking after the 

 typography generally. 



