PREFACE. 



A simple Catalogue of all tlie known recent Shells has long- 

 been a great desideratum to the Conchologist. The discoveries of 

 the many adventurous naturalists of the present century are of 

 such a prolific character, that an Index of Species referring to 

 the multifarious books and pamphlets wherein they have been 

 described or figured is greatly in request, if oiJy to counteract the 

 dangerous repetition of specific names. The increase of synonymes 

 arises chiefly from the circumstance of species being described in 

 different countries imder different names; and as the objects of 

 Natui-al History can only be satisfactorily determined by the aid of 

 an universal, not a national system of nomenclatui'e, too much 

 attention cannot be paid to the operations of foreign conchologists. 



The importance of keeping an Official Begister, as it Avere, of 

 Species, is in no branch of Natural History more strikingly de- 

 monstrated than in that of Birds ; the catalogue of ornithological 

 synonymes is said to be twice as extensive as that of authorised 

 names, or, in other words, the species of that portion of the Ani- 

 mal Kingdom have been named tlu-ee times over. This is not, 

 however, the case with Sliells; the nomenclature of Conchology 

 exliibits a very tolerable degree of purity, and it is confidently 

 hoped that the present effort to maintain it will prove effectual. 



The plan adopted in The Conchologist^s Nomenclatoe, is 

 that of an alphabetical list of species, in a systematic arrangement 

 of Genera ; a line is devoted to each species, the specific name 



