Il8 THE OYSTER. 



In order to serve this purpose the shells must be 

 perfectly clean, and as the old dead shells, which 

 have lain for a long time upon the oyster-beds, are 

 torn to pieces by the boring sponge and covered with 

 mud and slime, hydroids, sea-weed and sponges, they 

 are much less effective than those which are placed in 

 the water just before the spawning season. 



In regions where there is no danger from frost, or 

 where the young growth is to be planted in deeper 

 water before winter, the shells may be deposited at or 

 even above low-water mark, and in the sounds of 

 North Carolina oysters thrive even at high-tide mark. 

 The shells should be deposited in the early summer 

 in June, July and August in localities where there is 

 enough current to sweep the swimming young past 

 them. A hard bottom is to be preferred, but this 

 method may be employed with great advantage upon 

 any soft bottoms which are near the surface. In this 

 case the shells should not be uniformly distributed, 

 but placed in piles or ridges. If these ridges are 

 properly arranged with reference to the direction of 

 the current, they will produce secondary currents, and 

 will thus cause the soft mud to flow off between them. 

 In this way any bottom which is bare or nearly bare 

 at low tide, and which is exposed to the winds and 

 waves, may in time be swept nearly clear of mud. 

 Each time the tide comes in the mud is stirred up and 

 suspended in the water, and as the tide ebbs this sus- 

 pended matter is swept into the channels between the 

 obstructions and is carried away. Shells are very 



