* 



SYNOPSIS OF thp: family venerid.t^ and of the 



NORTH AMERICAN RECENT SPECIES. 



B}^ WiLiJAM Hkai;ky Dall, 



Honontrji ('iirator, Division of Mollnsks. 



This synopsis is one of a series of similar summaries of the families 

 of bivalve mollusks which have been prepared by the writer in the 

 course of a revision of our Peleeypod fauna in the light of th(^ material 

 accumulated in the collections of the United States National Museum. 

 While the lists of species are made as complete as possible, for the 

 coasts of the United States, the list of those ascribed to the Antilles, 

 Central and South America, is pro])ably subject to considerable addi- 

 tions when the fauna of these regions is better known and the litera- 

 ture more thoroughly sifted. No claim of completeness is therefore 

 made for this portion of the work, except when so expressly stated. 

 So many of the southern forms extend to the verge of our territory 

 that it was thought well to include those known to exist in the vicinity 

 when it could l)e done without too greatly increasing the labor involved 

 in the known North American list. 



The publications of authors included in the bibliograph}' which 

 follows are referred to by date in the text, but it may be said that the 

 full explanation of changes made and decisions as to nomenclature 

 arrived at is included in the memoir on the Tertiary fauna of Florida 

 in course of pul)lication by the Wagner Institute, of Philadelphia, for 

 the writer, forming the third volume of their transactions. The rules 

 of nomenclature cited in Part 111 of that work (pp. .561-56.5) are 

 thor^e upon which this revision has been foiuided, and are believed to 

 expi(\ss the opinions of the majority of those who have given thorough 

 stud}- to the subject of nomenclature. Authors wdio do not accept 

 the British Association rules, as thus developed, can not expect to tind 

 theii' personal views reflected in this revision. 



It may be thought that the su])division of groups has been carried 

 farther than desirable, to which the writer can only rejily that in 

 tracing the genealogy of our recent species through the Tertiary, 



Proceedings U. S. National Museum, Vol. XXVI— No. 1312. 



335 



