| Planorbella duryi & Planorbella scalaris Comparison |
 |
|
FIG. 739. Planorbella duryi form seminolis | FIG. 740. Planorbella scalaris |
| Burch, J. B., 1982. Freshwater snails (Mollusca: Gastropoda) of North America. E.P.A., Cincinnati, vi + 1-294 incl. numerous B&W plates and figs. April. |