306 ANIMAL SKETCHES. CHAP. 



I have not been able to glean any anecdotes of the in- 

 telligence of oysters. The most favourable report I can 

 give is from the pages of the Rev. W. Bingley's Animal 

 Biography. " The oyster has been represented, by many 

 authors," he says, " as an animal destitute not only of 

 motion, but of every species of sensation. It is able, how- 

 ever, to perform movements which are perfectly consonant 

 to its wants, to the dangers it apprehends, and to the 

 enemies by which it is attacked. Instead of being desti- 

 tute of sensation, oysters are even capable of deriving some 

 knowledge from experience. When removed from situa- 

 tions that are constantly covered with the sea, they open 

 their shells, lose their water, and die in a few days. But 

 when taken from similar situations, and laid down in 

 places from which the sea occasionally retires, they feel the 

 effect of the sun's rays, or of the cold air, or perhaps appre- 

 hend the attacks of enemies, and accordingly learn to 

 keep their shells close till the tide returns." From this it 

 would seem that if an oyster be left high and dry he 

 briefly considers his situation ; if he deems it probable 

 that the tide will rise and again submerge him, he shuts 

 his shell and determines to hold out as long as he can. 

 But if he thinks there is no chance of the tide's returning 

 he gives way to despair, opens his valve and dies. Per- 

 sonally I don't believe that the oyster reasons thus. A.S to 

 his facts, however, Dr. Bingley seems to be right. Just as 

 some fresh- water organisms may be gradually accustomed 

 to water with a greater and greater amount of salt, until 

 they can live in sea-water which would have killed them 

 had they suddenly been placed in it, so may oysters be 

 gradually accustomed to a longer and longer exposure to 

 the air without gaping. And this fact is turned to 

 practical account in the so-called oyster-schools of France. 

 But on the amount of intelligence involved in the process 



