i'HE NAUTILUS.- 67 



PELECYPODA. 



Lampsilis ventricosa (Barnes), Station 2, rare. 

 Lampsilis radiuta (Dillwyn). Stations 1, 2, common. 

 Anodonta margintita (Say). Station 2, common. 

 Um'o nasutus (Say). Stations 1, 2, common. 

 Unio complanatus (Solander). Stations 1, 2, common. 



GASTROPODA. 



Campeloma decisum (Say). Station 6, rare. 

 Canipeloma inteymm obesum (Lewis). Stations 2, 3, rare. 

 Valvata lewisii (Currier). Station 2, rare. 

 Bythinia tentactilafa (Linn.), Station 5, common. 

 Goniobasis livescens (Menke). Stations 2, 6, common. 

 Physa yyrina (Say). Station 5, common. 

 Planorbis trivolvis (Say). Stations 2, 4, 6, common. 

 Planorbis binneyi (Tryon). Station 2, common. 

 Planorbis bicarinatus (Say). Station 2, common. 

 Planorbis campanulatus (Say). Stations 2, 4, G, common. 

 Planorbis parvus (Say). Station 5, rare. 

 Planorbis hirsutus (Gould). Station 5, common. 

 Segmentina armigera (Say). Stations 2, 6, common. 

 Lymnsea stagnalis appressa (Say). Stations 2, 3, common. 

 Galba palustris (Mu'ller). Stations 2, 5, 6, common. 

 Strobilops labyrinthica (Say). Station 4, not common. 

 Bifidaria contracta (vSay). Station 5, common. 

 Succinea ovalis (Say). Station 5, common. 

 Succinea retusa (Lea). Stations 4, 5, common. 

 Polygyra tridentota (Say). Station 5, common. 

 Polygyra albolabris (Say). Station 5, common. 

 Polygyra fraterna (Say). Stations 4, 5, common. 

 Circinaria concava (Say). Station 4, not common. 

 Vitrea hammonis (Strom). Stations 4, 5, common. 

 Vitrea indentata (Say). Station 5, common. 

 Eucomdus fulvus (Mull). Station 4, rare. 

 Zonitoides arboreus (Say). Stations 4, 5, common. 

 Ayriolimax campestris (Binney). Station 5, common. 

 Phihinycus carolinensis (Bosc.). Station 5, rare. 

 Pyramidnla alternata (Say). Stations 4, 5, common. 

 Helicodiscus parallelus (Say). Station 4, common. 



