THE OYSTER. 39 



and is near the middle of the valve. The oyster has 

 but one adductor muscle, and this is an immensely 

 strong one. It joins the valves where the round pur- 

 ple spots appear. 



The oyster animal is nearly like the clam animal. 

 It is entirely soft and without bones a true mollusk. 

 The same kind of a slippery mantle lies between it and 

 the inside of the shell, though this mantle does not 

 completely envelop the mollusk. The oyster has no 



Oyster Shells. 



foot. What does it want of a foot? It spends nearly 

 its whole life fastened to the bottom. Nature is very 

 economical, and would not bestow a foot where one can 

 not be used. 



When the valves are open, the mantle sometimes 

 stretches down and throws its fringe beyond the lower 

 or ventral edge of the shell. In the border of the 

 mantle is the sense of touch; and here are the eyes, 

 if there are any ; and the ears are not far off. Oysters 

 close their valves at the slightest noise ; and a brush 

 of the hand over the water where they lie, when the 

 light is strong, will produce the same effect. Along 



