VI PREFACE. 



The answer to these questions lies in the different methods of our scieiuitic co-workers. It would 

 certainly not be uimatural, on receiving a large manuscript, to issue it at regular intervals. The letterpress, 

 however, is not printed and revised according to parts, but according to chapters ; when a prhited sheet is 

 ready it is dated and must at once be issued. We have also to consider the authors, whose manuscript must 

 not be delayed,'lest they be anticipated by another's publication. 



It is therefore impossible to give beforehand the exact date of publication of each future part. Only 

 this much can be said toda}', that, after the Palearctic Noctuids with the exception of the two last and rather 

 small groups (end of the Quadrifidinae and Hypeninae) have appeared and after four of the six groups of 

 Geometrids have been issued in the three parts following, the Palearctic portion of the work will shortly be 

 completed, so that the Exotic division can be issued much more rapidly. 



The third point at which we aimed was to render the work inexpensive for the purchaser. WTiether 

 we have succeeded in realising this is for our subscribers, and not for us, to decide. The work was meant to 

 be in reach even of collectors of only very moderate means. The price of the rather large second Volume 

 has worked out at less than 30 shillings for subscribers, and by comjjaring our text and plates with those of 

 other equally cheap publications the reader must judge for himself whether the quality of the more than 

 3000 diai^noses and nearly 2500 figures justifies this sum. But while doing so he must not forget that the 

 price for subscribers of the two Palearctic volumes still in the course of publication will be considerably 

 less, as they are condensed into very few parts. The subscribers price for the entire volume of Geometridae 

 (dealmg with about 3000 forms) will scarcely exceed 10 shillings. 



We therefore conclude Volume II in the confident expectation that the same reception will be accorded 

 to it as to Volume I. The lenient and considerate criticisms the work has so far received leads me to hope 

 that its modest aim of bjing essentially a work of reference has been recognised and appreciated. But just 

 as in the introduction to Volume I I had to meet the charge that the beauty of the plates suffered thi-ough 

 so many figures representing only half a specimen, so again today I have to answer a criticism arising 

 from misconception. It has been considered a grave fault that the composition of the various paragraphs 

 is not uniform throughout the work. This allegation was founded on the absolutely erroneous premise that 

 all forms dealt with in one paragraph were always considered to belong to the same species. It is, how- 

 ever, quite outside the province of this work to determme the degree of relationship of one form to another. 

 A paragraph is meant to deal with forms closely allied; it is not my intention at all to influence the per- 

 sonal opinion which any one may have on the above questions according to his own experiences. Had 

 we entered into the disputes about the specific distinctness of forms, etc. — which anyhow appear to me 

 rather futile — , the work would have become much more bulky and scarcely as useful. Naturally, in by 

 far the greater number of cases the forms are so arranged that those placed together in one paragraph 

 as being closely allied or similar are in fact forms of the same species. But where this is not the case 

 the reader will please remember that the "Macrolepidoptera" is a work of reference and not a series of cri- 

 tical monographs, and further, that where the text gives more information this is a voluntary contribution 

 on the part of the author. 



Just as far removed from the scope of the "Macrolepidoptera" was a decided position with regard to 

 the question of nomenclature. We could not make up our minds to follow implicitly the preliminary code of 

 so-called "international rules of Nomenclature", and how well founded our scruples were has been proved 

 by the overwhelming majority by which this code has been rejected — in some countries by 90 per cent 

 of the votes. We have adhered essentially to the law of priority and only admitted exceptions to 

 this rule for very strong reasons, i. e. if the strict application of priority would have changed long-established 

 names. But the opinion of those readers who do not admit any exceptions to the law of priority has also 

 been taken into consideration inasmuch as a slight alteration of our original plan has enabled us to give 

 an extensive synonymy and to include the synonyms in the Index to each volume. 



In the sixth preface to Vol. I of the Macrolepidoptera I proffered our hearty thanks to all who 

 have assisted in the undertaking, and now I have again great pleasure in thanking particularly the authors 

 of the letterpress of the various groups, many of which presented great difficulties. We are no less indebted 

 to the owners of collections who gave most efficient help by lending specimens and whose names have been 

 mentioned in Vol. I; also to our lithographers, Messrs. Werner and Winter, of Frankfurt a. M., whose 

 plates, without laying any claim to artistic and decorative effect, can bear any comparison as regards 

 utility ; and last but not least I nmst thank the publishers of the work, who have strenuously endeavoured 

 to comply with even the most exacting demands. Both they and the editor will try to prove their gra- 

 titude for the appreciation shown in the urgent demands of their readers for a continuation of the work 

 by producing the separate parts still more rapidly than before, though during the last three years the 

 time elapsed between the issue of any two parts was on an average less than two days. 



Before I close this preface to Vol. II I should like to repair an omission caused by my absence 

 abroad when Vol. I was concluded; I mean a statement of the reason for our change of programme. The ori- 



