IV PREFACE. 



by the Smithsonian Institution. In the remainder of the work 

 the descriptions of the " Genera of Recent Mollusca have been 

 adopted." 



The original figures of shells and lingual dentition were drawn 

 by Mr. E. S. Morse, of Gorham, Maine. 



The subject is brought down to January, 18C4. 



W. G. BIXXEY. 



BcELiNGTON, N. J., September, 1865. 



