PREFACE. 



fHE study of the causes of the variation of lepidoptera has now 

 become such an acknowledged part of our work, that there 

 appears to be but little need to explain the necessity for bringing out a 

 systematic and descriptive volume of the varieties of a part of one of 

 our most interesting groups of lepidoptera. 



At present, th'e whole of the records of our varieties are scattered 

 through numberless magazines and other works, published in different 

 countries. Through these, one has to wade for the items of informa- 

 tion required about any individual species, the search probably ending 

 in failure, and thus involving waste of valuable time. 



Causes of variation cannot be successfully worked out, without 

 the widest and most general information concerning the species about 

 which enquiries are made. It is with the view of extending the 

 information at present available that the present volume is being pub- 

 lished. 



There was an outcry a short time since, in certain quarters, con- 

 cerning the naming of varieties. Among our numbers there will 

 always be a certain proportion of collectors, who are unable, from 

 various causes to work up such a comprehensive subject as variation, 

 and yet wish to be thought quite au fait with every branch and 

 phase of it. The use of varietal names need not trouble such ; the 

 names are made for the use of those devotees in various countries who 

 wish to carry on their work without the waste of time, and who 

 cannot afford to make a long written description every time they wish 

 to speak of a certain varietal form. 



The matter in the book is principally new, that relating to the 

 Cymatophoridce, Bombycoidce, Apamidce, and Caradrinidce almost entirely 

 so. The skeleton of the material used in Bryophilidce, Leucanidce and 

 Apamidce (in part) appeared in a series of papers I wrote in the * Ento- 

 mologist,' 1888 188U under the title of ' Contributions towards a List 

 of the Varieties of the British Noctuse occurring in the British Islands.' 

 These, however, were of such a fragmentary nature that it was thought 

 best to write up the greater part of the general notes on the species 

 de novo, and simply use the varietal descriptions. 



It remains for me to most heartily thank (1) those gentlemen, who, 

 on the withdrawal of the above-mentioned papers from the ' Entomo- 

 logist,' kindly offered to subscribe to the present volume, and thus 

 guaranteed that no pecuniary loss should fall on me ; (2) Those friends 

 who have given me most kindly help either in obtaining material from 

 old entomological literature, in correcting the proofs and suggesting 

 additions, &c., or in providing me with unusual forms of lepidoptera 

 for description. 



J. W. TUTT. 



May, 1891. 



