XXIV PREFACE TO THE SECOND EDITION. 



foreign naturalists seem to have felt the necessity of establish- 

 ing divisions in those immense genera, in which such incon- 

 gruous species were formerly heaped together ; their groups 

 are now precise and well defined, their descriptions sufficiently 

 detailed, their figures scrupulously exact even to the most 

 minute characters, and very frequently of the greatest beauty. 

 Scarcely any difiiculty remains therefore in determining the 

 identity of their species, and nothing hinders them from com- 

 ing to an understanding with respect to the nomenclature. . 

 This, unfortunately, has been almost neglected ; the names of 

 the same genera, the same species, are multiplied as often as 

 they are spoken of ; and should this discord continue, the same 

 chaos will be produced that previously existed, though arising 

 from a different cause. 



I have used every effort to compare and approximate these 

 redundancies, and forgetting even my own little interest of 

 author, have often given names which seem to have been form- 

 ed expressly to avoid being compelled to avow the borrowing 

 of my divisions. But in order thoroughly to execute this un- 

 dertaking, this pinax of the animal kingdom, which becomes 

 daily more and more necessary, to examine its proofs, and to fix 

 on the definite nomenclature that would be adopted, by basing 

 it on suflicient figures and descriptions, requires more space 

 than I can dispose of, and a time imperiously claimed by other 

 works. It is in the " History of Fishes," which, assisted by 

 M. Valenciennes, I have commenced publishing, that I intend 

 to give an idea of what I think might be effected with respect 

 to all parts of the science. This is a mere abridgement, a 

 simple sketch fortunate will I be if I succeed in rendering 

 it correct in all its parts. 



Various descriptions of a similar kind have been published 

 on some of the classes, and I have carefully studied them all, in 

 order to perfect my own. The ^'Mammalogie'^ of M. Desma- 

 rest, that of M. Lesson, the "Traite sur les Dents des Qua- 

 drupedes" of M. Frederick Cuvier, the English translation of 

 my first edition by Mr Grifiith enriched by numerous additions 

 chiefly by Hamilton Smith, the new edition of the '^ Ma- 



