MOLLUSKS 



THE FRESH WATER MUSSEL 

 Anodonta, or Unto 



General Suggestions. — (i) The mussel is found in 

 all streams and lakes of this country, and is therefore an 

 easy specimen to procure. If it is desirable to use the com- 

 mon quahog (venus), which is for sale in the markets at 

 all seasons, the following directions with slight additions 

 about the orifices, incurrent and excurrent, will be found 

 applicable. 



(2) Specimens may be obtained from the streams and 

 ponds with a rake or dredge of any kind that will reach 

 to the bottom of the water. At certain times they may be 

 found near the shore, and when the water has fallen con- 

 siderably they may be found in the mud and sand. 



(4) If an aquarium, or a tub, be filled with water 

 and a bed of sand be put in the bottom, mussels may be 

 kept alive for an indefinite period. 



(4) Have present during the study several shells that 

 may be made to fit together in the right order, and if pos- 

 sible other bivalve shells, as oyster, quahog, mya, and other 

 forms that may be convenient. 



(5) The preserved material may be kept in seventy per 



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