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LIFE OF THE PLEISTOCENE 



Sphaerium sulcatum (Lam.) 

 striatinum (Lam.) 



Helicina occulta Lam. 



Valavla tricarinata Say 



Amnicola species 



Physa integra Hald. 

 " sayi? Tappan. 



Ancylus rivularis Say 



Planorbis antrosus Conrad 

 " parvus Say 

 " dilatatus Gould 



Galba obrussa (Say) 

 " galbana (Say) 

 " htimilis modicalla (Say) 



Carychium exiguum (Say) 



Succinea ovalis Say 

 " avara Say 



Vallonia gracilicosta Reinh. 



Bifidaria armifera (Say) 

 " contracta (Say) 



Sphaeriidae 



Pisidium abditum (Hald.) 

 " compressum (Prime) 



GASTROPODA • 



Helicinidae 



Valvatidae 



Valvata bicarinata Lea 

 Amnicolidae 



Amnicola emarginata Kiister 

 Physidae 



Physa gyrina Say 

 Aplcxa hypnorum (Linn.) 



Ancylidae 



Flanorbedae 



Planorbis albus Miiller ( = hirsutus Gld.) 

 Segmenlina armigera (Say) 



Lymnaeidae 



Galba caperata (Say) 

 " palustris (Miiller) 

 " reflexa (Say) 



Auriculidae 



Carychium exile H. C. Lea 

 Succineidae 



Succinea retusa Lea 



Valloniidae 



Vallonia costata (Miiller) 



PtJPILLIDAE 



Strobilops labyrinthica (Say) 

 " virgo (Pilsbry) 



Endodontidae 



Sphyradium edenlulum allicola (Ingersoll) Helicodiscus parallelus (Say) 



Pyramidula cronkhitei anthonyi Pilsbry Pyramidula alternata (Say) 



Zonitidae 

 Zonitoides arbor ea (Say) Euconulus fulvus (Miiller) 



" minusctda (Binney) Vitrea hammonis (Strom.) 



Helicidae 

 Polygyra monodon (Rackett) Polygyra profunda (Say) 



" midlilineata (Say) 



