PREFACE. V 



synonymy and in referring to previous writers. All the synonyms proper have been intro- 

 duced, — that is, all the different specific denominations under which one and the same species 

 has been described ; but when the difference m the denomination was limited to the genus, 

 I have selected those only by which the knowledge of the natural affinity of the species 

 has really been advanced. I have likewise omitted all references to descriptions or notes by 

 which no new fact has been added to the previously known history of a reptile. Changes 

 in the generic nomenclature are frequently ventured upon now-a-days in the most unscru- 

 pulous manner by persons Avho, having seen only a small proportion of the species, copy the 

 delusive characters of their new genera from the original descriptions, and with their most 

 slender materials attempt to break up well-characterized and natural genera. Whilst the 

 genus is that which, in the zoological system, simplifies most, and at the same time pre- 

 serves the greatest variety of types — is therefore that which is most frequently used in our 

 philosophical intercourse and operations, and ought to be as comprehensive as the natural 

 affinities of the species will allow — any trifling character is now used to give a new generic 

 name to every two or three species ; and I am afraid this is more frequently done for the 

 purpose of introducing the author to notice than from a desire to advance science. For it 

 will be observed that, generally, the men who thus endeavour to burden our memory are 

 not satisfied with having their name recorded in connexion with their systematic produc- 

 tions, but must have all the old, well-known species assigned to their credit also. Under 

 all circumstances, such a change of the name of the authority for binomial designations is 

 quite irrational, nor does our method imply anything which is untrue. Thus, when we 

 speak of a Eumeces punctahis, L. (instead of Wiegm.), or of a Biopa punctata, L. (instead 

 of Gray), every herpetologist knows that Linnaeus did not use the terms Eumeces and 

 Riopa, and therefore that his name can have reference to the species only : which informa- 

 tion is of greater value than that Wiegmann and Gray referred the species to some modern 

 genus, as it guides us at once to the typical description on which the species for ever 

 depends. Moreover, in numerous instances we are by no means certain whether the person 

 who uses a new generic name really has identified the species of the elder author : thus, for 

 instance, if Wiegmann or Gray had referred to their genera Eimieces or Riopa a species 

 which they considered as the Lacerta punctata of Linnaeus, but which in reality is different 

 from it, every one who used the expression Eumeces pimctatus, Wiegm., or Biopa punctata, 

 Gray, for the Linnean species, would commit an error. Therefore I hold, with the pro- 

 moters of the rules of zoological nomenclature which were laid before the Meeting of the 

 British Association in 1842, that the claims of an author who is induced to make alterations 

 in previously existing generic arrangements do not extend beyond them, but should be duly 

 recorded at the proper place, viz. in the synonymy of the genus. 



On the other hand, I consider it inconsistent to apply the same rule to generic names : 

 whilst a species when once properly described and named is fixed, a genus remains for a 

 longer or shorter period in a fluctuating state, and frequently scarcely more than the name 

 of old genera remains, or even a more modern generic name has quite a different significance 

 from that attributed to it by its original inventor. In these cases science ought to pay more 

 deference to the kernel than to the shell ; and if, in an instance like that of the Ophidian 

 genus Ablabes proposed by Dumeril and Bibron, the original compilation is never adopted, 



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