. CIS 



PREFACE, 



The following work is designed to supply a aeficiency 

 which has long been felt by the cultivators cK American 

 Natural History ; for while the quadrupeds and birds of 

 our country have been described and figured with great 

 fidelity and elegance, some other branches of Zoology 

 have experienced comparative neglect. Among these 

 is CoNCHOLOGY, a science replete with interesting details, 

 whether we examine the seemingly innumerable cha- 

 racters of the shells themselves, or turn our attention to 

 the organized beings which inhabit them. 



It is proposed, however, to limit the present undertaking 

 to the Marine Shells inhabiting the coast of North America ; 

 inasmuch as several able naturalists, especially Messrs. 

 Say and Lea, are now occupied with our fresh water and 

 land shells, the results of whose labours will doubtless 

 supply all that may be requisite in these departments. 



The North American sea shells have received more or 

 less attention from nearly all the systematic writers on 

 Conchology : many of the species were familiar to Lin- 

 naeus ; others were first noticed by Lamarck ; and Mr. 

 Say, with his usual industry, has described a considera- 

 ble number. The periodical publications of this country 

 and of Europe contain various additional notices, and 

 the interests of science seem now to require, that all 

 these scattered details should be embodied in a system- 

 atic form, with corrections and additions suited to the 

 present state of our knowledge. 



The great attention which has been of late years given 

 to Conchology, has necessarily removed much of the 

 obscurity and corrected many of the errors of this science. 

 Numerous shells which were formerly supposed to be 

 different in specific characters, are now proved to be 

 identical; while others which were published as new, 

 are found to have been well known to our predecessors. 



