Excerpt from History of British Mollusca, Vol. 4: And Their Shells
All the terrestrial, and the majority of freshwater Gasteropodous Mollusca, breathe air, and are provided with a pulmonary cavity, or sac, instead of gills. Over the walls of this Это и многое другое вы найдете в книге History of British Mollusca, Vol. 4 (Edward Forbes)