THE EDITOR'S PREFACE. 



THE distinguished position occupied by Professor Agassiz, 

 from his numerous and important works on Natural Science, 

 especially his " Recherches sur les Poissons Fossiles," renders 

 any eulogium on the contributions of so eminent a naturalist 

 to zoological literature unnecessary. 



The " Principles of Zoology," of which the present volume 

 forms the first part, was designed by Professor Agassiz, in 

 conjunction with Mr. Gould, as a text-book for the use of 

 higher schools and colleges, for which it is undoubtedly well 

 adapted, as the style is simple, the arrangement clear, and 

 the range of subjects 'important and comprehensive: it is, 

 moreover, well suited for imparting to the general reader a 

 sound knowledge of Physiology and the Philosophy of Natural 

 History. 



In introducing the present edition of this work to the English 

 public, the Editor desires to state that he has endeavoured still 

 farther to increase its value, by large additions to several of 

 the chapters. In doing so, he has availed himself of the 

 treatises of Cuvier, Carus, and Meckel, on Comparative Ana- 

 tomy ; and those of Tiedeman, Miiller, Valentin, and Wagner, 

 on Physiology. From Dr. Willis's excellent translation of the 

 Elements of the latter profound author much additional matter 

 has been derived. 



The additions from Wagner are duly acknowledged in the 

 body of the work : those by the Editor are indicated by his 



