270 Shark and Compa?iy 



Lesser Butterfly ray (Gymnura micrura). 



Courtesy, Harvard Museum of Comparative Zoology 



The big D. centroiira is found in the coastal waters of the western 

 North Atlantic from Georges Bank and Cape Cod to Chesapeake Bay, 

 to Cape Hatteras and possibly to Florida. The little D. sab'ma is com- 

 monly found in shallow waters of the western North Atlantic, from 

 Florida northward to Chesapeake Bay. It is also prevalent in the Gulf 

 of Mexico, and— like many Sting rays— enters rivers. It has been caught 

 more than 200 miles up the Mississippi River, and in Lakes Ponchartrain 

 and Borgne, Louisiana, and in the lakes of the St. John River, Florida. 



Probably the most common Sting ray along the North American At- 

 lantic Coast (Dasyatis sayi Lesueur, 1817) spends most of its time lying 

 on the bottom near shore with only its eyes and spiracles exposed. It 

 thus becomes a sort of aquatic land mine for the unwary wader who 

 steps on it. These Sting rays, which grow to about 36 inches in width, 

 are not always found on the bottom, however. During their annual 

 migrations up the Atlantic Coast each summer, they often vigorously 

 slap the surface of the water with their flapping pectorals and lashing 

 tails. Sometimes a school of them will noisily sweep into a bay or an 

 inlet, usually unnerving the bather who recognizes them. D. sayi is 

 found from southern Brazil northward to Chesapeake Bay and Virginia, 

 and sometimes New Jersey. It has also been reported occasionally as far 

 north as Massachusetts. 



The American Pacific Coast is prowled by the Diamond (or Rat- 



