Owing to some delay in the publication of the English edition of the work, a German translation by my friend, Dr.Hans Kurella, editor of the _Centralblatt fuer Nervenheilkunde_, has already appeared (1896) in the _Bibliothek fuer Sozialwissenschaft_.

The German edition contains some matter which has finally been rejected from the English edition as of minor importance; on the other hand, much has been added to the English edition, and the whole carefully revised.
I have only to add that if it may seem that I have unduly ignored the cases and arguments brought forward by other writers, it is by no means because I wish to depreciate the valuable work done by my predecessors in this field.

It is solely because I have not desired to popularize the results previously reached, but simply to bring forward my own results.

If I had not been able to present new facts in what is perhaps a new light, I should not feel justified in approaching the subject of sexual inversion at all.
HAVELOCK ELLIS.
CONTENTS.