Baker — The Molluscan Fauna of McGregor, Jowa. 
CAMPELOMA suBsOoLIDUM Anthony. 
Common. 
Family PHysIDAs. 
PHYSA GYRINA Say. 
Common in creek near Pictured Rocks. 
Family PUpmIDAE. 
StTRoBILOPS virGoO Pilsbry. 
Common. 
BIFIDARIA ARMIFERA Say. 
Only one specimen collected. 
Family SUCCINEIDAE. 
SuccCINEA RETUSA Lea. 
Common. 
Family HE.Icrpae. 
POLYGYRA CLAUSA Say. 
Common. 
be 
PoLyGYRA THYROIDES Say. 
Apparently not common. 
POLYGYRA MULTILINEATA Say. 
Not common. 
POLYGYRA PROFUNDA Say. 
Not common. 
POLYGYRA HIRSUTA Say. 
Only two dead specimens found. 
PoLyGyRA MONODON Var. fraterna Say. 
Fairly common. 
Family CrrcrnarupDaAg. 
CIRCINARIA CONCAVA Say. 
Fairly common. 
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