INTRODUCTION. 



This work is intended to assist students of the Mollusca in the United 

 States, by bringing together for their use a large number of excellent 

 figures of species belonging to or illustrating the fauna of the southern 

 and southeastern coasts of the United States, from Cape Hatteras 

 south to the Straits of Florida and west to Mexico, with the adjacent 

 waters. 



These figures are explained and connected by a catalogue of the mol- 

 lusks known to inhabit that region, either from the presence of authen- 

 ticated specimens in the National Museum or on the authority of repu- 

 table naturalists who have collected in the region and whose specimens 

 have been seen or reliably identified. 



This catalogue, arranged for convenience in tabular form, includes 

 not only the species which are illustrated on the plates but all other 

 species common to the region, as far as known. 



Hitherto there has been no catalogue which covered just this ground. 

 There are several catalogues of marine species of particular West In- 

 dian islands. Th -re are several lists of Floridian shells, the fullest 

 and best being that just completed in the Proceedings of the Daven- 

 port Academy of Sciences by Mr. Charles T. Simpson. These all refer, 

 however, to a much more restricted field than the present list, and the 

 nomenclature in some cases is more or less inaccurate, as of course must 

 be the case with all lists, each of which, in spite of its inevitable im- 

 perfections, should show some advance over its predecessors. This is 

 all that the writer would claim for the present catalogue, which, owing 

 to peculiar circumstances, has been rather hurriedly decided upon and 

 rapidly prepared. 



In order that the number of columns in the table should be com- 

 pressed within the space of two opposite pages and yet admit of the use 

 of brevier type, it has been necessary to limit the number of stations in 

 the geographical series so that each column should represent a stretch 

 of coast and seaward from it the archi ben thai area or continental slope 

 beyond the fifty-fathom line to the oceanic floor. Then various puz- 

 zling questions arose in attempting to decide which column should be 

 used in certain cases; as, for instance, in specimens dredged in the path 

 of the Gulf Stream between Cuba and the Florida Keys. They might 

 with equal propriety be assigned to the ''Florida Keys" or to the 

 "West Indies" column, or to both. In all cases the facts have been 



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