Chapter Foub 



FOSSIL SHELLS OF THE NEW JERSEY 

 BEACHES 



It is well known that the oceans have not always 

 been in exactly the same places that they are today. 

 We know that at certain times in the history of the 

 earth the seas were higher and covered certain parts 

 of what is now land. Variations in the amount of 

 water in the sea together with movements of the land 

 have brought about these various changes in the 

 position of the oceans. 



AVe find evidence for these ancient seas in the 

 fossil remains of sea animals — vertebrate and in- 

 vertebrate — that are found far from the present 

 seashore, even on the tops of mountains. Fossils 

 are defined as "remains or traces of animals or 

 plants that lived in a period earlier than the 

 present." They may be petrified remains, or they 

 may be unaltered, consisting of the hard parts of 

 the original animal, such as bones or shells. Ordi- 

 narily fossil sea animals are easily recognized 

 because they are different from living species and 

 because they are often found far from salt water. 



Fossil shells are often found washed up on the 

 sea beaches where they have been carried from some 

 nearby deposits on land or perhaps from some 

 deposit at the bottom of the sea. Many of these 

 shells are unaltered, and are .difficult or impossible 

 to distinguish from recent shells. In many cases, 

 the species are extinct and are not to be found living 



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