FOSSIL SHELLS of NEW JERSEY COAST 29 



salt marshes by means of hydraulic dredging from 

 30 to 50 feet below the bottom of the thoroughfares 

 or channels back of the coastal islands. In the sand 

 thus pumped to the surface are often shells and other 

 remains of sea animals. These are probably from 

 the Cape May formation which underlies these 

 coastal islands, and which, as we have just seen, 

 was deposited during the last interglacial stage. 

 Many of the species now live only in more southern 

 waters and are the same as those frequently found 

 washed up on the beach. Two Mile Beach, south 

 of Wildwood, is the best place to collect these fossil 

 shells. Other similar hydraulic fills are found all 

 along the New Jersey coast, as well as at a few places 

 on the " Del-Mar- Va Peninsula." 



Some of the commoner of these warm water 

 fossils are listed in the chapters on mollusks. 

 The following is the complete list of the Pleistocene 

 shells of New Jersey which at present are restricted 

 to the warmer seas south of that state: Terebra 

 concava, T. dislocaia, Fulgur perversum, Polinlces lactea, 

 Sinum perspectivum, Thais floridana, Fissurella alternata, 

 Mangelia stellata, Cantharus cancellaria, Area ponderosa, 

 Transenella stimpsonij Bangia cuneata, Odostomia im- 

 pressaV3,T. granitma, Chione cribaria. In addition these 

 fossil deposits contain many species still living in the 

 region. 



A few species of fossil shells from the New Jersey 

 beaches are known alive only from the seas north of 

 New Jersey and thus indicate a former colder tempe- 

 rature. It is probable that these shells lived in the 

 sea during Glacial times, perhaps 25,000 years ago 

 when the climate was colder than it is today because 

 immense ice sheets covered the northern parts of 

 earth. 





