MOLLUSKS. 



THE RIVER MUSSEL. 

 (Unio.) 



Haunts. This animal is common in all our rivers and 

 small lakes. It is found on the bottom, usually partly 

 buried in sand or mud. As it moves about, it makes a 

 trail through the mud or sand, a shallow groove, with 

 abruptly sloping sides ; and, by observing its track at 

 the edge of the water, it may often be more easily found. 

 Occasional specimens may be picked up at the bank, 

 but usually larger ones will be found farther out. They 

 may be raked ashore with a long-handled garden rake, 

 or drawn up with a long-toothed lawn rake from a boat, 

 or, in warm weather, most rapidly obtained by wading 

 out on a submerged sand bank and picking them up by 

 hand. The dead and empty shells strewing the banks 

 will be a guide to the best places to search for live 

 specimens. 



When a river is falling after a flood, many mussels will 

 be found close to the banks, and many others may be seen 

 out on the banks, where they have been left high and dry 

 by the receding waters, and where they have died. This 

 is a casualty of a very common kind among the lower 

 animals. 



Specimens collected in the field may be carried home in 

 a bucket of water, and kept alive in an aquarium impro- 

 vised from a tub or a water-tight box, with a layer of sev- 



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