356 The American Geologist. December, looi 
Amnicola limosa (Say) Hald. Quite common. 
Valvata bicarinata (Lea). Rather rare. 
LAMELLIBRANCIIS. 
Sphaerium rhomboideum (Say). Pr. Quite common. 
Calyculina partumeia (Say). Common. 
Calyculina secure (Prime). Not common. 
Calyculina transversa (Say). Very common. 
PisiDiUM ABDITUM Hald. Very common. 
Unio* subrostratus Say. Quite common. 
Anodonta grandis Say. Common. 
Anodonta imbecillis Say. Common. 
c. species of the larger creeks and the river. 
GASTEROPODS. 
Pleurocera subulare (Lea) Try. Common. 
SoMATOGYRUS suBGLOBOSUS (Say). Common 
Somatogyrus INTEGER (Say) Biiiii. 
Campeloma subsolidum (Antli.) Call. Very common. 
Campeloma . Two other possible species. 
Lioplax subcarinata (Say) Tros. Not common. 
Ancylus rivularis Say. Very common. 
LAMELLIBRANCHS. 
Sphaerium sulcatum (Lam.) Pr. Very common. 
Sphaerium solidulum (Pr.) Quite common. 
Sphaerium striatinum (Lam.) Pr. Rather frequent. 
Unio aesopus Green. Common. 
Unio alatus Say. Common. 
Unio anodontoides Lea. Common. 
Unio capa Green. Rather rare. 
Unio coccineus Hild. Common. 
Unio cornutus Barnes. Quite common. 
Unio don.\ciformis Lea. Quite common. 
Unio ebenus Lea. Rare. 
Unio elegans Lea. Common. 
Unio ellipsis Lea. Rather rare. 
Unio fr.\gosus Con. Quite common. 
Unio gr.'^cilis Barnes. Common. 
Unio laevissimus Lea. Common. 
Unio ligamentinus Latn. Very common. 
Unio luteolus Lam. Quite common. 
Unio metanever Raf. Common. ^ 
Unio obliquus Lani. Not common. 
Unio orbiculatus Hild. Rare. 
Unio parvus Barnes. Common. 
Unio plicatus Le S. Very common. 
Unio pustulosus Lea. Very common. 
