448 The Molluscan Family Plauorhidae 



PLATE 106 



Shells of Planorbidae 



1-3. Helisoma duryi seminole Pilsbiy. Florida. U.S.N.M., 99301. 



4. Helisoma connnti Dull. Calocsahatchee River. Florida. U.I., Z40570. 



5-7. Helisoma conanti Dall. Caloosahatchee River, Florida. B1107. 



8. Helisoma disstoni (Dall). Vero, St. Lucia Co., Florida. U.S.X.M., 331971. 



9-11. Helisoma species? Asecibo, Puerto Rico. U.S.X.M., 535394. 



12-15. Helisoma disstoni (Dall). Canal, Palm Beach Co., Florida. M.C.Z., 99182. 



16. Helisoma corpulentum midticostatum F. C. Baker. Lake Kahnipiminanikok, 



Ontario, Canada. Young. U.I., Z32628. 



17. Helisoma corpulentum (Say). Lac la Croix, Ontaria, Canada. Youno;. U.L, 



Z32626. 



18. Helisoma whiteavesi F. C. Baker. Lac des Mille Lacs, Ontario, Canada. Holotype. 



U.L, Z32311. 

 19,20. Helisoma ivhiteavesi F. C. Baker. Lac des Mille Lacs, Ontario, Canada. Para- 

 types. U.L, Z32312. 



21. Helisoma ivhiteavesi F. C. Baker. Lac des Mille Lacs, Ontario, Canada. Paratype, 



Immature. U.L, Z32313. 



22. Helisoma corpulentum (Say). Kettle Fall.'^, Rainy Ri\er District. Ontario, Canada. 



Began as a corpulentum and on last whorl changed form of shell toward that of 

 multicostatuyn. U.S.N.M., 361737. 



All figures are enlarged about P,-'> diameters 



