494 The Molluscan Family Planorbidae 



PLATE 129 



Shells of Planorbidae 



1-3. Tropicorbis orbiculus (Morelet). Near San Miguel, Cozumel Island, Quintana 



Roo, Mexico. M.C.Z., 75102. 

 4. Tropicorbis obstructus (Morelet). Same as above. M.C.Z., 75102. 

 5-7. Tropicorbis orbiculus (Morelet). {^^ Planorbis licbmanni Dunker). Vera Cruz, 



Mexico. U.S.N.M., 210881. 

 8,9. Tropicorbis obstructus (Morelet). Same locality as above. U.S.N .M., 210881. 

 10-15. Tropicorbis orbiculus (Morelet). Chamiai Creek, below Valles, Mexico. U.I., 



Z28528. 

 16. Tropicorbis orbiculus (Morelet). Catanas Lake, El Abra, Mexico. B1191. 

 17-22. Tropicorbis obstructus donbilli (Tristram). Edentate. Guadalupe River, Victoria 



Co., Texas. U.S.N.M., 464970. 

 23-25. Tropicorbis obstructus donbilli (Tristram). Edentate. Brownsville, Texas. 



B1187. 

 26-31. Tropicorbis orbiculus dunkcri F. C. Baker. New name. Dry pool near Tampico, 



Mexico. B1184. 

 32-36. Tropicorbis orbicidus dunkcri F. C. Baker. Los Canoas, Mexico. B2113. 

 37-42. Drepanotrema heteropleurus Pilsbry and Vanatta. Lake Titicaca, Peru. Topo- 



types. Agassiz Expedition. 



All figures are enlarged about two diameters 



