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ABOUT THE MUSSEL. 



"mantle") simple or fringed; the said pallium, which 

 secretes the shell, being simply an expansion of the dorsal 

 integument. It does not possess a distinct, differentiated 

 head; and the mouth is just situated at what may be 

 called the anterior extremity of the body. It opens into 

 a gullet, and the gullet into a stomach consisting of a 



thin, white, opaline membrane. The liver is large and 

 well-developed ; the respiratory organs consist of two 

 larnelliform gills, placed on each side of the body. 



A remarkable organ of the mussel is its foot which is 

 small, and when not in motion semi-lunar, but capable of 

 elongation until it resembles a kind of conical tongue, 



