THE SCALLOP. 57 I 



position, which contains as much sea-water as is 

 sufficient to cover them. 



The Oyster has been represented by many au- 

 thors as an animal destitute not only of motion but 

 of every species of sensation. The abbe Dicque- 

 maire, however, has shown that it can perform 

 movements perfectly consonant to its wants, to the 

 dangers it apprehends, and to the enemies by which 

 it is attacked. Instead of being destitute of sensa- 

 tion, Oysters are even capable of deriving some 

 knowledge from experience. When removed from 

 situations that are constantly covered with the sea, 

 from w 7 ant of experience, 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 w r hich the sea occasionally retires, they feel the 

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

 apprehend the attacks of enemies, and accordingly 

 learn to keep their shells close till the tide returns*. 



Oysters breathe by means of gills. They draw 

 the water in at their mouth, a small opening in the 

 upper part of the body, drive it down a long canal 

 that constitutes the base of the gills, and so out 

 again, retaining the air for the necessary functions 

 of the body. Thus their ejecting of water seems 

 to serve the double purpose of aiding the motion 

 of such as are loose, and of supplying the animals 

 with air. 



THE SCALLOP f. 



The Scallop has the power of progressive motion 



—— — . 



* Journal de Physique. 



+ Synonyms. rOstera maxima. Linn. Pecten maximn.-. 



Great Scallop. Venn. 



