PREFACE. xiii 



For the class Caudata I have adopted in part the arrangement of Cuvier, 

 and in part that of Fitzinger. 



A word or two with respect to the use of specific names. — I have endeavoured 

 invariably to retain, with the name of the Naturalist describing it, that by which 

 the animal was first made known. These should always be retained, even if bad, 

 though the generic names may, indeed must, often be changed, according to the 

 lio-ht thrown by anatomical investigation upon the affinities that animals bear to 

 each other in their structure and organization. Thus in assigning the Emys 

 Floridana to Leconte, I only mean to retain the specific name given by him to a 

 certain animal which he first described; and it is not to be supposed that he 

 estabfished the genus Emys, any more than the genus Testudo, (Testudo 

 Floridana,) to which he refers it. 



I have only here to do with species and specific names; in the anatomical 

 part of this work it will be shown why one generic name is preferred to 

 another. In the catalogue of synonymes will be seen not only the different 

 specific names, but also those of the genera under which difTerent Herpetologists 

 have arranged our Reptiles. 



The habit adopted by several late Naturalists, of changing the names by 

 which animals were first described, even though for better and more characteristic 

 denominations, has already led to great confusion, and must lead to greater, 

 since few persons are likely to agree in the characters they think most 

 important. 



