396 The MoUuscan Family Planorbidae 



PLATE 80 



Shells of Planorbidae 



1-3. Helisotna anceps (Menke) = Planorbis bicarinatus Sowb. and P. bicarinatus Say. 



From Delaware River II/2 miles above Plum Point, New Jersey. Like Say's 



figures. U.L, Z25738. X2. 

 4-6. Helisoma anceps (Menke). South Street Brook, Auburn, New York. Strongly 



carinated form. U.L, Z25934. X2. 

 7-8. Helisoma scalare (Jay). Everglades, head of Miami River, Dade Co., Florida. 



Baker coll., 237L X2. 

 9. Helisoma duryi seminole Pilsbry. Lake Eustis, Florida. Physoid shell. Baker 



coll., 3977. X2. 

 11-12. Helisoma duryi nurmale Pilsbry. Lake Pinsett, Florida. Typically planorboid 



shell. U.L, 41489. XIYj. 

 13-15. Helisoma trivolvis (Say). Braddocks Bay, near Rochester, New York. Lake 



Ontario. U.L, 29789. XlV->. 

 16-18. Helisoma campanulatum (Say). Thousand Island Park, St. Lawrence River, 



New York. U.L, 27112. Xli/1'. 

 19-21. Helisoma multivolvis (Case). Howe Lake, Marciuette Co.. Michigan. Baker 



coll., 1962. X2. 

 22-24. Planorbarius corneus (Linn.). Rhone River, France. U.L, 25740. Xli/2. 



