wu 



uld fill several pages if 1 enmnei'ated all wild, often unasked, have sent or offered me rarities aixl 

 uniques from their collections, and I must abstain from mentioning every one who has helped. It is to 

 these and to the collaborators — not to the editor — that the thanks are due of all those who had to 

 abstain hitherto from publishing contributions to the systematics of Lepidoptera or bionomical observations 

 on account of the great obstacles constantly encountered in procuring the necessary literature, which is 

 often very difficult of access. We grieve to say that many of those whom we should have liked to thank 

 in this place have already passed from among us. 



May a kind reception be accorded to the work. As it is meant to be only an elementary manual, 

 supplying a generally felt want, and has no higher pretensions, we may hope that critics will not be too 

 severe. In consequence of the knowledge and industry of some of our collaborators many manuscripts, 

 instead of being the short sketches asked for, were monographs of as high a scientific value as anything 

 that had been published on the subject. We trust that what we give more in these instances than was 

 promised will be regarded as compensating for the mistakes, omissions and other inaccuracies which may 

 be found in other i)arts of the work. The many imperfections will be considered, I trust, as an anti- 

 cipated and inevitable though regrettable consequence of our endeavour to attain the objects which wo 

 had in view as the most important in our undertaking: Comprehensiveness, rapidity of publication, and 

 cheapness. 



EI-Kantara, loth of June 1909. 



Dr. Adalbert Seitz, 



Darmstadt. 



