Conditions in the Northern Field 189 



Oysters from some localities are thin shelled, as in the 

 eastern end of the Great South Bay, the home of the 

 Blue Point. Usually the shell is thick and heavy. Its 

 thickness depends on the amount of lime in solution in 

 the water. In the Carolina sounds and southward, as 

 also in the Gulf of Mexico, natural oysters are charac- 

 terized by relatively small and much elongated shells. 

 But without question, all of these variations in appear- 

 ance are due simply to local differences in environment, 

 and there is a single species, Ostrea virginica, on the At- 

 lantic and Gulf coasts. In this form the sexes are sepa- 

 rate. It is sometimes stated that an individual may 

 change its sex, being male one year and female another, 

 but there is no foundation for such a statement. 



One important element in the development of the 

 modern industry in the North was the aid received from 

 the Chesapeake. The planting of small oysters never 

 began anywhere until the natural beds had been practi- 

 cally destroyed. The demand for small seed oysters then 

 outgrew the supply. 



As early as 1825, a few small seed oysters from Ches- 

 apeake Bay were transferred to waters near Staten Island. 

 At about the same time the town of Wellfleet on Cape 

 Cod had sent to Buzzards Bay and then to Connecticut 

 for seed oysters. Finally it began to receive them from 

 Virginia, and during the decade following 1850, from 

 one hundred to one hundred and fifty thousand bushels 

 were transported each year from the Chesapeake to beds 

 near this town. The Civil War made it impossible to 

 obtain much seed, and Wellfleet did not subsequently 

 recover its position as an oyster center. 



During these same years just preceding the war, Nar- 

 ragansett Bay, Long Island Sound, New York Bay, and 



