96 



Lithasia obovata Say. 



Ohio River (Marsh). 



Genus Pleurocera Rafinesque. 



Pleurocera alveare Conrad { — nupera Say). 



Little Wabash and Saline rivers (Hinkley) ; Ohio River 

 (Marsh) ; Southern Illinois (UlfTers). 

 Pleurocera canaliculatum Say. 



Wabash and Ohio rivers (Hinkley) ; Wabash River (Marsh) ; 

 Mt. Carmel, Wabash Co. (Nelson); Southern Illinois (Ulffers); 

 Golconda, Pope Co. ; Saline River, Saline Co. (State Labora- 

 tory). 



Pleurocera elevatum Say. 



Cook Co. (Baker, Jensen) ; Joliet, Will Co. ; Kankakee River 

 (Ferriss, Handwerk) ; Kishwaukee and Kaskaskia rivers 

 (Hinkley); Illinois River (Marsh); Spoon River (Strode); 

 Peoria, Peoria Co. ; Pekin Lake, Tazewell (Jo. ; Golconda, Pope 

 Co.; Saline River, Saline Co.; Kaskaskia River, Bartelso, Clin- 

 ton Co. ; Pistakee Lake, Lake Co. ; Skillet Fork, Wayne Co. ; 

 Duncan's Mills and Bernadotte, Fulton Co. ; Little Muddy 

 River, Franklin Co. ; Havana, Mason Co.; Kishwaukee River, 

 Winnebago Co. ; Carlyle, Clinton Co. ; Lake Michigan, Chicago, 

 Cook Co. (State Laboratory). 



Pleurocera elevatum lewisii Lea. 



Northern Illinois; Fox River (Calkins) ; Utica, La Salle Co. ; 

 Joliet, Will Co. ; Kankakee River(Ferriss) ; Quincy, Adams Co. 

 (Hart) ; La Salle Co. (Huett) ; Peoria Co. (Lea, Lewis, Marsh, 

 Tryon) ; Illinois River; Canton, Fulton Co. (Nason) ; Spoon 

 River (Strode) ; Fulton Co. (Wolf) ; Peoria, Peoria Co. ; Quiver 

 and Matanzas lakes, and Illinois River, Havana, Mason Co. ; 

 Pekin Lake, Tazewell Co. ; Thompson's Lake, Fulton Co. ; Milan, 

 Rock Island Co. (State Laboratory). 



Pleurocera Horencense Lea. 



Wabash River (Marsh). 



Pleurocera lesleyi Lea. 



Ohio River (Marsh). 



Pleurocera moniliferum Lea. 



Wabash, Little Wabash, Saline, and Ohio rivers (Hinkley, 

 Marsh) ; Ohio River (Lea). 



