MOLLUSCA FROM INDIANA AND OHIO 



445 



of faunas belonging to the Sangamon or Peorian intervals, and the 

 study of this material from a wide area would aid very largely in 

 understanding the interglacial and postglacial migrations of many 



TABLE III 

 Land Shells of Two Indiana .Deposits 



Lawrenceburg Flat Rock River 



Vallonia pulchella 



Cochlicopa lubrica 



Gastrocopta contracta Gastrocopta contracta 



Gastrocopta armifera 



Pupoides marginatus 



Succinea species 



Succinea avara vermeta 



Helicodiscus parallelus Helicodiscus parallelus 



Pyramidula perspectiva 



Pyramidula cronkhitei anthonyi 



Pyramidula solitaria Pyramidula solitaria 



Pyramidula alternata Pyramidula alternata 



Gastrodonta ligera Gastrodonta ligera 



Vitrea hammonis Vitrea hammonis 



Vitrea indentata Vitrea indentata 



Circinaria concava Circinaria concava 



Polygyra monodon Polygyra monodon 



Polygyra stenotrema Polygyra stenotrema 



Polygyra mitchelliana 



Polygyra clausa 



Polygyra thyroides Polygyra thyroides 



Polygyra pennsyhanica 



Polygyra elevata Polygyra elevata 



Polygyra appressa ..." 



Polygyra palliata Polygyra palliata 



Polygyra multilineata ' 



Polygyra zaleta Polygyra zalela 



Polygyra albolabris 



Polygyra profunda Polygyra profunda 

 Polygyra inflecta Polygyra inflecta 

 Polygyra tridentata Polygyra tridentata 

 Polygyra fraudulenia 



species of moUusks. A case in point is the presence of the minute 

 fresh-water snail known as Pyrgulopsis sheldoni in this old inter- 

 glacial deposit. This species was described from material dredged 



