PREFACE 



rpHE importance of earthworms in questions relating 

 -^ to geographical distribution is so universally 

 admitted that it seemed to me convenient to embody 

 in a short volume the principal facts. 



It became necessary in order to accomplish this 

 task in an adequate fashion to preface the dis- 

 tributional facts with some anatomical and zoological 

 data. I have reduced this section of the book to a 

 minimum and I trust that the illustrations will enable 

 the reader, who is not specially acquainted with the 

 structure of these animals, to obtain an idea of their 

 general features and variability in external cliaracter 

 and internal anatomy. While the use of technical 

 terms is inevitable in presenting such details, it 

 will be found, I think, that a reference to the 

 figures will render them intelligible. 



