INTRODUCTION 



The following plates of illustrations of Lepidoptera are more or 

 less in the nature of an experiment. Realizing how many of the 

 rarer species of our North American moths had never been figured 

 and of how many others the existing figures were very inadequate, 

 we began about a year ago to experiment with photography as a 

 means of reproduction. 



Our method of procedure was as follows : On receiving a batch 

 of material from one of our various collectors we would pick out the 

 rare species of which perfect specimens were present, and these we 

 would spread up and photograph immediately on their removal from 

 the spreading board, before the wings had time to sag or rise. The 

 method has several drawbacks ; in the first place it has been naturally 

 impossible to follow any particular systematic grouping, and species 

 belonging to the various families or subfamilies are mixed up in the 

 most heterogeneous manner; in the second place when 15-20 speci- 

 mens are photographed on one plate at one time there is great diffi- 

 culty in securing a perfect photograph of each individual specimen ; 

 some of the specimens, owing to the depth of the color, will require a 

 slightly different exposure, and in others again the differentiations of 

 the various colors will only partially be reproduced when an ordinary 

 negative is used. The first objection has been more or less counter- 

 balanced by an index to the species figured in this work, and we have 

 endeavored, as we gained more experience in photography, to offset 

 the second and more serious objection by the use of special isochro- 

 matic plates, ray-screens, etc., and by the more careful selection, 

 where possible, of the specimens for each individual plate. Those 

 species which on the earlier plates have proved unrecognizable we 

 have, in most instances, reproduced a second time on one of the later 

 plates. 



Finding that on the whole a very recognizable figure might be 

 obtained by photography we photographed further a number of the 

 "type" specimens contained in the Barnes collection, all of which are 

 now figured for the first time ; in cases where the types have been in 

 poor condition we have, if possible, figured a more perfect specimen 

 of the same species. 



Our first intention had been to issue a very limited edition of about 

 25-30 copies, illustrated by the original photographs mounted on card 

 board, and simply for distribution among the various large collections 



