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LIST OF SPECIES 
The following species have been found in the marl deposits : 
MOLLUSC A 
Class Pelecypoda 
Family Spkaeriida 
Sphaerium simile Say 
Sphaerium solidulum Prime 
Sphaerium stamineum Conrad 
Pisidium abditum Haldeman 
Pisidium compressum Prime 
Class Gastropoda 
Family Helicidce 
Polygyra albolabris Say 
Polygyra ( Stenotrema ) monodon Rackett 
Family Endondontidee 
Pyramidula ( Patula ) alternata Say 
Helicodiscus lineatus Say 
Family Succinidce 
Succinea ovalis Say 
Family Lymnaeidce 
Lymnaea stagnalis appressa Say 
Lymnaea obrussa Say 
Lymnaea obrussa decampi Streng 
Lymnaea galbana Say 
Planorbis antrosus Conrad 
Planorbis campanulatus Say 
Planorbis altissimus Baker 
Planorbis deflectus Say 
Family Phy sides 
Physa gyrina Say 
Family Amnicolidce 
Amnicola limosa Say 
Amnicola porata Say 
Amnicola lustrica Pilsbry 
Family Valvatidce 
Valvata sincera Say 
Valvata tricarinata Say 
