7/j-O OYSTERS, AND ALL ABOUT THEM. 



become covered with small oysters which have fastened to 

 it, although it may not be within miles of any natural 

 oyster bank. The fact that the young may be collected in 

 this way, in any part of the Chesapeake bay, shows that 

 the young oysters must settle down upon the bottom in 

 nearly all parts of the bay, and we should expect the adults 

 to have an equally general distribution. 



" This is far from the case, and nothing would be farther 

 from the truth than the idea that the bottom of the waters 

 of the oyster region is uniformly covered with oysters, and 

 that it is only necessary to throw a dredge overboard, and 

 drag it along the bottom for a short distance, in order to 

 bring it up full. Nothing could be a greater mistake, for 

 both in this country and in Europe the oysters are restricted 

 to particular spots, " beds" or " banks," which are as well 

 defined, and almost as sharply limited, as the tracts of 

 woodland in a farming country. These beds are so well 

 marked that they can be laid down on a chart or staked 

 out with buoys, and even in the best oyster regions they 

 occupy such an inconsiderable part of the bottom that any 

 one ignorant of their position would have very little chance 

 of finding oysters by promiscuous dredging. Although 

 the young are distributed every year, by tides and currents, 

 to all parts of the bottom, the dredge very seldom brings 

 up even a single oyster outside the limits of the beds. 



" The restrictions of the oysters to certain points does 

 not appear to depend upon the supply of food, nor upon 

 the character of the water, but almost entirely upon the 

 nature of the bottom. The full-grown oyster is able to live 

 and flourish in soft mud, as long as it is not buried too 

 deeply for the open end of the shell to reach above the 

 mud, and draw a constant supply of water and food into 

 the gills. 



