10 INTRODUCTION. 



papers on material gathered by the U. S. Pish Commission, contributed 

 by Prof. A. E. Verrill to the Transactions of the Connecticut Academy 

 of Sciences, to the American Journal of Science, and to the Reports of 

 the U. S. Fish Commissioner for 1871-'72 and 1883. 

 Then follow ten columns, each representing a district, as follows : 



1. New Jersey (N. J.). This includes the coast aud adjoining archibentlial area 



from the entrance of Chesapeake Bay to Sandy Hook at the south point of 

 entrance to New York Bay and Harbor. 



2. Virginia (Va.). This includes the coast, etc., from Cape Hatteras, North Caro- 



lina, to the month of Chesapeake Bay. 



3. Hatteras (Hat.). This district extends from the month of the Savannah River, 



Georgia, to Cape Hatteras, North Carolina, with the adjacent archibenthal 

 area. 



4. Georgia (Ga.). At Cape Canaveral, Florida, tlie path of the Gulf Stream 



seems to diverge more from the main coast than previously. It seems that 

 a good many southern species do not reach farther north on the shores 

 than Cape Canaveral. Therefore this district from Cape Canaveral to the 

 Savannah River has been separated from the one that I have called East 

 Florida. 



5. East Florida (East Fla.). This includes the region between Biscayne Bay and 



Cape Canaveral. 



fi. FloridaKeys (Fla. Keys). Thisregion, very intimately connected, faunally, with 

 the northern shon-s of Cuba opposite, and with the Bahamas, includes the 

 region south of Biscayue Bay on the east, and south of the southern en- 

 trance to Charlotte Harbor on the west side of the Peninsula, to and includ- 

 ing the Keys and Tortugas reefs and islamls. 



7. West Florida (West Fla.). This includes the region north of the south entrance 



io Charlotte Harbor and westward to the Mississippi delta along the shore 

 and the archibenthal area of the Gulf of Mexico westward from the penin- 

 sula to \\ est longitude 90, and southward to the trough between Cuba 

 and Florida. 



8. Texas (Tex.). In this district I include the shores of the United States from 



the Mississippi delta to the Rio Grande and the archibenthal area south- 

 ward from it in the Gulf of Mexico to Yucatan. 



9. West Indies (West Ind. ). In this district, for want of space on the page, I have 



been obliged to include all of the Antilles, the Bahamas, and the shores and 

 islands of the Caribbean Sea. The particular southern extension of a 

 species not known to extend throughout this area will be indicated by the 

 entry in the "southern limit" column. No species not figured on the plates, 

 or common to the coast of the United States, is admitted in the catalogue, 

 so that the West Indian or Antillean fauna properly so-called is almost 

 wholly excluded from this enumeration. Some few species, which are 

 strictly Antillean, as far as known, are included because it was necessary 

 to refer to their figures on the plates, but the distribution as recorded in 

 the table will enable any one desiring to discuss the purely North Ameri- 

 can species to identify and exclude the.se extra-limital forms without dif- 

 ficulty. To make the distinction more apparent their names appear in 

 italics in the catalogue. 



10. Bermuda. The island of Bermuda aud its associated reefs is intimately allied 

 by its mollusk fauna to the region of the Florida Keys and Northern An- 

 tilles. A column has therefore been provided for it. 



A few species common to our southern coast are also found without 

 essential modification still living on the west coast of Central America, 



