IV PREFACE. 



of classification, but the result is not by any means so satisfactory 

 as I could have desired ; in fact, the structure of the palpi and 

 the venation of the wings offer but few marked variations for 

 characteristic distinctions. The principal features as regards the 

 palpi exist in Sarrothripa and Phtheochroa (see PL III. figs. 1 

 & 7) ; and with respect to the structure of the anterior wings, 

 the costal fold deserves especial notice (see figs. 4 & 7 of Plate I.); 

 for, although this character has long since been observed, it has 

 never before been used in classification. It will be seen that my 

 second family (the Plicata) is founded upon it ; and by it, at all 

 events, one insect has been removed from former systems to its 

 more natural location I mean Xanthosetia inopiana, which has 

 hitherto been associated by Stephens and Doubleday* with 

 X. hamana and Zcegana, with what reason does not appear ; but 

 is now removed to the Halonotce, following H. turbidana, which 

 it certainly resembles both superficially and structurally. I could 

 multiply instances, but this one is sufficient for my purpose. 



The illustrations of the venation of the wings in Plates III. & 

 IV. vary somewhat from those given by previous authors ; for 

 the reason of this I refer the reader to the Explanations of the 

 Diagrams at the top of Plate III. As this is peculiarly inter- 

 esting to me individually, I invite the observations of others on 

 this branch of the subject, as I think it may lead ultimately to 

 some important physiological results. 



In consequence of structure being the basis of the present 

 arrangement, great alterations have necessarily been made. 

 These alterations I have the presumption to dignify with the 

 name of improvements, because I deem them as effecting a 

 nearer approach to the true ' Sy sterna Naturse ' than any hi- 

 therto published. Doubtless many persons will differ from me 

 in this particular ; but I can only say that I look forward for a 

 better system from abler hands, and if my labours should lead in 

 any way to such a result, I shall consider them amply repaid. In 

 the present work there are probably many errors, both of omis- 



* In the second edition of Mr. Doubleday's List I see inopiana is now placed 

 in hie genus Cochylis ; a position, which, if structure is to be considered, cannot 

 be maintained. 



