PREFACE. 



I have great pleasure in offering a third volume of British 

 Lepidoptera to my brother entomologists, and I sincerely hope that 

 they may be able to give it the same satisfactory reception as its 

 predecessors. I can assure them that, whatever labour was expended 

 on volumes i and ii, the work of preparing this volume has been 

 much greater than that of either. This has been due essentially 

 to the fact that the species discussed in this volume are all exceedingly 

 well-known, and, as a result, they have been treated by so many 

 authors, that a complete grasp of the literature relating to them, 

 has been more difficult to obtain than when dealing with a group that 

 is but little known and has been but little studied. One could possibly 

 write half-a-dozen volumes of this size de novo, in the time that one 

 has to spend in doing justice to the work of one's predecessors and 

 seeking out minor details that one may have missed in one's own 

 work. 



It was quite clear from the commencement that, if the species 

 were to be treated at anything like the length that their previous 

 study deserved, there could be no general chapters in this volume. 

 The amount of material relating to Lasiocampa quercus alone that 

 had to be digested was so great, and the different points of view 

 from which it had to be treated were so varied, that it was clear 

 that the account of this species alone could be made to form the 

 basis of a liberal education in lepidopterological science. Again, 

 the consideration of the Attacids and the Sphingids on a wide 

 basis also opened up so many and so different views of entomological 

 science — synonymical, biological, physiological and classifactory — 

 that it was self-evident that these chapters would more than recom- 

 pense for any feeling of disappointment that might be felt by some 

 in the absence of any summaries of special points relating to the 

 general subject. 



We are, in spite of our efforts, entirely dissatisfied with our 

 knowledge of the relationship of the various families of the 

 Saturniides inter se, of those of the Sphingides inter se, and of 

 these two superfamilies to each other. One might have supposed 

 that of these two superfamilies, composed of species of such large 

 size, lepidopterists knew almost everything that could possibly 

 be learned. As a matter of fact there can be very few superfamilies, 

 even among the smallest lepidoptera, of which our knowledge is 

 more vague and less satisfactory than is that of our knowledge 

 of the Sphingids to-day. We can only claim to have tried to 

 throw light into some of the dark and difficult places* 



