400 The Molluscan Family Planorhidae 



PLATE 82 



Shells of Planorbidae 



1,2. Helisoma ancejhs (Menke). Ashhmd, Virginia. Resembling Menke's figure. B999. 



3-5. Helisoma anceps (Menke). Below dam at Lake Junalaska, North Carolina. B1819. 



6-8. Helisoma anceps (Menke). Long Lake, Alpena, Michigan. Resembling Rackett's 

 figm'e of Helix angulata. BIOOL 



9-n. Helisoma anceps (Menke). Spring Grove, Dove Co., Alabama. Walker coll. Re- 

 sembling Conrad's Planorbis antrosa. U.M., 6740L 



12-15. Helisoma anceps (Menke). Potomac River, Fort Washington, Maryland. 14, re- 

 sembling unicarinatum ; 15, resembling sayi. U.S.N.M., 364718. 



16, 17. Helisoma anceps (Menke). Blue Creek, Coeur d'Alene Mts., Idaho. U.M., 81780. 



18,19. Helisoma anceps (Menke). Portland, Oregon. Hemphill coll. C.A.S., 6875. 



20-22. Helisoma anceps striatum (F. C. Baker). Bay View, Milwaukee, Wiscon.^in. 

 From marl bed. B2851. 



23-25. Helisoma anceps shellense F. C. Baker. Shell Lake, Washburn Co., Wisconsin. 

 23, paratype, U.I., Z19354; 24-25, type locality, U.I., Z13474. 



26. Helisoma anceps (Menke). Portland, Oregon. U.C.M., 23143. 



27-29. Helisoma anceps niinnesotoise (F. C. Baker). Frontenac, Minnesota. Types. 

 B1002. 



30. Helisoma anceps (Menke). Priests Lake, Bonnar Co., Idaho. U.M., 81798. 



31. Helisoma anceps corrugatum (Currier). Northern part of Minnesota. B985. 

 32-34. Helisoma anceps sayi F. C. Baker. East Lake Okoboji, Iowa. Shimek coll., 



U.S.N.M., 476580. 



Figures are enlarged approximately two diameters 



