Planorbarius corneus. View of the sunken spire (held facing downwards in life)Planorbarius corneus. View of umbilicus (held uppermost in life)
References
^Duméril A. M. C. (1806). Zoologie analytique, ou méthode naturelle de classification des animaux, rendue plus facile à l'aide de tableaux synoptiques. pp. i-xxxiii [= 1-33], 1–344. Paris. (Allais).
^Linnaeus C. (1758). Systema Naturae per regna tria naturae, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. 10th edition. - Vermes. Testacea: 700-781. Holmiae. (Salvius).