468 



NATURAL HISTORY. 



extremely elastic hinge, which after the death of the animal 

 opens the shells widely. 



The Bivalves do not enjoy such powers of locomotion as the 

 Univalves, yet some, as the fresh-water mussel, can urge them- 

 selves along by means of a fleshy organ called the foot ; and so 

 powerful in some is this organ, that by means of it the animal 

 can not only burrow in the sand, but actually leap out of a 

 boat. The rapid opening and shutting of the valves is used by 

 some, as the scallop, as a means of progression. It is believed 

 that the Bivalves have no visual organs. 



The common SCALLOP is found along our southern coasts, 

 and in the seas of Europe.* This shell was formerly used as 

 the badge of a pilgrim to the Holy Land. 



" His pilgrim's staff he bore, 



And fix'd the Scallop in his hat before." 



OSTKEA. (Or. "Ocr^eov, an Oyster.) 



Edulis (Lat. edible], the Oyster. 



The COMMON OYSTER has been for many ages considered as 

 delicacy for the table. In the times of the ancient Homans, 



* It is a singular fact, that in the stomach of the common Scallop is found an 

 earthy deposit, which, when boiled in nitric acid in order to dissolve the animal and 

 other portions, exhibits under a powerful microscope animalcules precisely similar 

 to those which, in a fossil state, form the earth on which the town of Richmond in 

 America i.3 built. 



