The marine mollusk fauna of the Virginian area as a basis for defining Zoogeographical provinces

The marine fauna of the American Atlantic coast between Cape Cod and Cape Hatteras, the Virginian area, is placed by zoogeographers in different provinces: in the Transatlantic, or in the Boreal province. It is sometimes considered to be a province of its own, or only a transition between the Boreal and Carolinian province. The mollusk fauna of the Virginian area is compiled and compared with the faunas north and south of the area. As endemism is low, there is no reason to consider the Virginian area an autonomous zoogeographical province. The fauna is too much different from that of the Carolinian area, to combine both in one Transatlantic province. As most of the species are of boreal origin, there is less reason to consider the Virginian area as a transitional region between the Carolinian and the Boreal provinces than as belonging to the Boreal province, the percentage of boreal mollusks is large enough to include it in the Boreal province. A comparison of the northern Atlantic provinces of America and Europe shows that a different zoogeographical division of both areas is necessary, as a consequence of the currents: the transition between Labrador Current and Gulf Stream suppresses a temperate province on the American East coast, such as the Celtic province is on the European West coast.