SEA ANIMALS OF THE ATLANTIC COAST 21 



chapters when numerous species are recorded for the 

 first time in New Jersey far north or south of their 

 known distribution. 



Furthermore, many animals, common in shallow 

 water along the northeastern coast, extend south 

 in deeper water where the temperature is lower. 

 Certain echinoderms and mollusks, which are com 

 mon in shallow water along the coast of Maine and 

 Northern New England, extend their range as far 

 south as Cape Hatteras in water of considerable 

 depth. Among these may be mentioned the Green 

 Sea Urchin (Strong ylocent rot us drobachiensis) , the 

 Bloody Starfish (Henricia sanguinolerda) and the Sea 

 Scallop (Pecten grandis). 



In addition, certain northern animals extend 

 their ranges southward during the colder months 

 of the winter; conversely numerous southern ani- 

 mals migrate north of their normal range in the 

 warmest parts of the summer. 



There are so many factors that combine to 

 determine the distribution of marine animals that 

 it is very difficult to map even approximate zones. 

 Nevertheless, the above mentioned zones have cer- 

 tain characteristic species and are used as a matter 

 of convenience. 



