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NATURAL HISTORY. 



Family, Meleagrinidae. (Gr. 



MELEAGRIXA. 



Margaritifera (Lat. Margarita, a pearl ; fcro, I bear), the Pearl Oyster. 



The Chinese have a method of forcing oysters, or rather 

 mussels, to form pearls, by artfully placing beads in their shells, 

 round which a layer of nacre is deposited, and the beads then 

 perfectly resemble real pearls. 



THE MUSSEL. 



The SEA MUSSELS are usually fixed where the tide leaves 

 them alternately wet and dry, and it is worthy of notice that 

 those " shell-fish" which are exposed to variations of this kind 

 are enabled to close their shells so firmly as to prevent, any 

 evaporation. One species is extensively used as an article of 

 food. 



