This book is intended chiefly as a work of reference. As most Zoological Gardens are much alike, it is impossible to avoid a certain monotony in describing them. And yet each Garden has generally its own distinctive features. These I had the opportunity of observing in a tour which I made early this year, and I have tried to recount them in the following pages, after first giving the main facts connected with the foundation and development of the respective Gardens. In my descriptive walks round I invariably turned to the left on entering, and made my way round the Gardens back to the entrance again.