THE OYSTER. 117 



or gully containing water, and in this are placed 

 the fascines lengthways in a continuous line ; on 

 either side are ranges of tiles, some of them placed 

 in wooden frames ; they are laid in rows across 

 each other, each tile stack being lashed together so 

 as to prevent the displacement of the tiles. The 

 oysters are placed in small beds before and behind 

 each stack, narrow ways being left between ; a 

 boarded frame is also fastened above to keep all 

 the tiles in their proper position. 



In making a few observations on the enemies 

 of the oyster, I think it will be found in all 

 animals that multiply their species at a very 

 great rate, every individual brings forth its 

 thousands ; we find on the opposite side of the 

 balance sheet there are a great number of enemies 

 ever present to keep under the species and prevent 

 their increasing in an undue ratio. We may 

 divide these enemies into two classes, animate and 

 .inanimate. Among the former of course we must 

 place those creatures which actually prey on and 

 devour the oyster. Among the latter we include 

 those unfavourable conditions of soil, water, atmo- 

 sphere or temperature, which prevent the species 

 from reaching its proper development. I propose 

 now to treat of the former class. The first of these 

 is the whelk tingle or dog whelk, Purpura lapillus. 

 This mollusc is one of the greatest enemies to the 



