MOLLUSCA 143 



in many places the practice to save all the empty 

 shells and throw them back into the water. See 

 figure 23. 



After setting', the oyster grows and in about 

 two years (in New Jersey) will reach a market- 

 able size. Very often the oystermen will dredge 

 the young' oyster (spat) and replant them in order 

 to thin out the beds to avoid overcrowding. Some- 

 times oysters are transported a considerable distance 

 before replanting. 



In the United States, the oyster occurs from 

 Massachusetts to Southern Texas. As demon- 

 strated by the presence of large Indian shell heaps, 

 the oyster undoubtedly lived as far north t Maine 

 within the past few hundred years. There are 

 various species of oysters (Ostrea) in tropical waters, 

 and 0. virginica has been reported at lerst as far 

 south as Honduras. 



In New Jersey, the most important oyster 

 grounds are found in Maurice River r < a part 

 of Delaware Bay. The towns of Biva Port 



Norris are the center of the oyster indus. this 



State. 



The trade names of oysters such as "Lynn- 

 havens", "Blue Points" "Maurice River Salts", 

 etc. are local variations in size, shape, etc. probably 

 due to ecological conditions of the environment. 



Pecten gibbus irradians Lamarck (Bay Scallop) 



PLATE XV. Fig. 9 



This fan-shaped shell is found on all beaches 

 from New England to Florida. In this species the 

 "ears" of the shell near the beak are about equal in 

 size. 



