CONTENTS. 



Preface 



Systematic index 



Ampullakiib^ 

 Pomus 



Valvatid^ 



Valvata 



V1VIPARID.E 



Vivipara 

 Tulotoma 

 Melantlio 

 Lioplax . 



RlSSOID.5 . 



Bythinella 

 Tryonia . 

 Cochliopa 

 Gillia . 

 Somatogyrus 

 Amnicola 

 Fluminicola 

 Pomatiopsis 



Cyclophoriii^ . 



Chondiopoma 



Teuncatellid^ 



Truncatella 



Neeitid^ . 



Neritella 



HELICINIPiE 



Helicina 

 Addenda, etc. . 

 Index 



1 

 3 



8 



8 



16 



16 



33 



35 



55 



65 



67 



70 



72 



73 



76 



80 



89 



93 



95 



95 



97 



97 



100 



101 



107 



107 



113 



117 



( V ) 



