Preface to the English Edition. xxiii 



caterpillars, based on a broad ground, is as yet 

 wanting, although such a labour would be both most 

 interesting and valuable. Nevertheless, we know 

 considerably more of the life of caterpillars than 

 of any other larvae, and as we are also acquainted 

 with an immense number of species and are able 

 to compare their life and the phenomena of their 

 development, the subject of the markings of 

 caterpillars must from this side also appear as the 

 most favourable for the problem set before us. 



To this must be added as a last, though not as 

 the least, valuable circumstance, that we have 

 here preserved to us in the development of the 

 individual a fragment of the history of the species, 

 so that we thus have at hand a means of following 

 the course which the characters to be traced to 

 their causes the forms of marking have taken 

 during the lapse of thousands of years. 



If with reference to the question as to the 

 precise conditions of life in caterpillars I was 

 frequently driven to my own observations, it was 

 because I found as good as no previous work 

 bearing upon this subject. It was well known 

 generally that many caterpillars were differently 

 marked and coloured when young to what they 

 were when old ; in some very striking cases brief 

 notices of this fact are to be found in the works, 1 



1 A most minute and exact description of the newly hatched 

 larva of Chionobas Aello is given by the American entomologist, 

 Samuel H. Scudder. Ann, Soc. Ent de Belgique, xvi., 1873. 



b 2 



