LVir 



at that congress should lead to any other result and it is on that account 

 that I did not desire to take part in it. 



Although following the systematic arrangement of the late Snellen I have 

 found it necessary somewhat to modify it in connection with certain points which 

 I would further have discussed with him if he had lived. After consulting 

 Mr. Fruhstorfer I have had to include the species Ypthima J areas de Nic, 

 whose occurrence in Java was unknown to Snellen ; moreover, after careful 

 study of much more extensive material than was available to him I have 

 excluded from the present work the two species Ypthima Nigricans Sn. and 

 Cyllo Zithenius Herbst. The advice of Mr. Fruhstorfer and the inspection 

 of his extensive collection have been of great service to me. 



POSTSCRIPT. 



The issue of the present volume has been considerably delayed. Although 

 otherwise completed at the end of 191 1, the printing of the plates has encountered 

 many difificulties and consequently publication could only be effected in 

 1913. As a result, the report of the proceedings of the International Ento- 

 mological Congres held in 1 9 1 1 having reached me in the course of 

 191 2, I was able to acquaint myself with its conclusions on the subject of 

 mimicry, discussed by me at the end of the Introduction vide page LVI. 

 This circumstance induces me here to add a few observations on the subject. 



I there stated that for two reasons especially no useful purpose could be 

 served by such discussions. First, because, as I have already stated repeatedly, 

 the subject in question appears to me already to have been shelved in a scientific 

 sense and will, therefore, probably die a natural death ; so that the fact that a 

 few adherents continue to support it needs no further consideration. Secondly, 

 because experience has shown that on their part no scientific reasoning, no 

 adduction of proof or fundamental refutation, is to be expected but only records 

 of fresh observations which, having been explained from their one-sided point 

 of view, are regarded as confirming their theory which, however, with a 

 different interpretation is by no means the case, while they fail to refute the 

 latter. The report of the Congress, in my opinion, completely confirms my 

 attitude in this connection. 



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