vi PREFACE 



limit to the number which may be healthily main- 

 tained and exhibited. 



We have had the great advantage of having the 

 following pages overlooked by Mr. W. A. Lloyd, of 

 the Crystal Palace, to whom our best thanks are due 

 for many valuable suggestions. 



The work is now presented to the public in the 

 hope that it may add to the educational effects of 

 our public aquaria, and be the means of rendering 

 the education in zoology more popular and exten- 

 sive. 



