II PREFACE. 



As concerns the abbreviations of the author's names we have repeatedly deviated from the previous 

 schemes, correspondingly to the method adopted in our two preceding volumes. Our reason for this, which does 

 not always seem to have been understood, hes in the numerous mistakes which result from the want of clear- 

 ness in the customary abbreviations. Abbreviations such as "Wall.", which may mean Wallace or Wallengren, 

 "Rbr." (Rambur, Rober), "God." (Godart, Godman), "Butl." (Bitttel, Butler), "Dru." (Drtjry, Druce), 

 etc., have been replaced in the German edition by others (Rrrib., Rob., Wkr., Btlr., etc.), which have the advan- 

 tage of being distinctive. 



The geographical definition of the region is that of the earlier volumes. All the countries in the north of 

 the Old World with any considerable winter frosts are treated as Palearctic, so that Japan, Korea, China north 

 of the Yang-tse-kiang, the Tibetan highlands and the adjoining districts of Kashmir have been included; 

 all the districts without a true winter are excluded. In this matter my own observations have been of the 

 greatest value to me, as the impression which one receives when collecting in a district often differs consi- 

 derably from that obtained from a statistical survey of its fauna, in which the greatest rarities, scarcely ever 

 met with, figure equally with with its commonest characteristic butterflies. Statistics of the Palearctic Lepi- 

 doptera show us the genera Parnassius, Colias, Erebia, Sesia, etc. in the lists as predominant and often repre- 

 sented by a very large number of forms ; as a matter of fact, however, these genera are by no means charac- 

 teristic, on account of their sporadic, rare or local occurrence, and the most characteristic butter- 

 flies are just those of which a small number of species or forms are included in the statistical lists, such as 

 Gonepteryx, Vanessa, Coenonympha, Xylina, etc. Here I have followed entirely the impression received in my 

 studies in East Asia, where 16 times and collecting at all seasons of the year I crossed the southern boundary- 

 line of the Palearctic Region. True transitional districts, where the species met with in several days' collecting 

 represented 50% of obviously Palearctic and 50% of unquestionably Indian forms, I have not met with, and 

 — except perhaps in Kashmir — such can scarcely exist to the extent that is usually assumed. 



The system employed for the Noctuidae agrees in general with that used in Hampson's excellent 

 work. Lederer's system (antiquated in addition), the setting aside of which some critics have thought fit to 

 denounce, was not even taken into consideration, inasmuch as Lederer himseK, who was certainly well capable 

 of judging, described it as inapplicable to a work including also the non-Palearctics. For the rest it has from 

 the beginning not been within mj^ purpose to furnish in the "Macrolepidoptera" an entirely new and reformed 

 system, but a practical, time-saving and cheap work of reference, which shall in the first place help and sti- 

 mulate. For arguments on systematic questions, which require to be founded on detailed evidence, space is 

 altogether wanting. Where such was available, it has been placed at the disposal of the authors for biological 

 additions, which deal with something more than the bare appearance of the insects. 



It would also have been a great mistake, just at the critical moment when a heated controversary is 

 being carried on concerning the fundamental principles of nomenclature, to tie down the work to a hard 

 and fast nomenclatural scheme. From the moment when the opponents of absolute priority succeed in proving 

 that the pursuit of the principle of priority with retrospective application leads to constant fluctuations rather 

 than to stability, science finds itself confronted with entirely new questions, and whether we shaU finaUy 

 have recourse to the sovereignty of commissions or of codes of rules will depend upon whether the latter 

 are able to secure general aceeptance. It has therefore not been judged expedient to bind the authors of the 

 separate sections down to the observance of any fixed code; we have thought it better, while holding fast to 

 those of the "rules of nomenclature" which can be regarded as actually accepted, to sanction a freer and more 

 practical view of the subject, where such was preferred by our collaborators. 



As with the form, so also with the method of publication of the third volume of the 'Macrolepidoptera", 

 the principles laid down in the preface to the two first volumes have been applied. The rapidity with which 

 the later plates and chapters of the third volume appeared shows a considerable increase on the earlier parts, 

 while concurrently the exotic part of the work has also been materially advanced and the larger half of the 

 last Palearctic volume (vol. IV) published. And likewise in our aim of cheapness an advance may be recognized, 

 as the supplying of 4338 coloured figures and the full text has surpassed our previous offers. 



As quite recently new descriptions of Noctuids have been published weekly, our earlier parts are neces- 

 sarily not quite complete to-day. It was nevertheless needful, in order to bring the Palearctic part to a con- 

 clusion at all, to dispense with further insertions, references and appendices. This could, however, be the more 



