Sentence Examples


  • Shell spirally coiled; operculum horny; intertentacular lobes absent.
  • Shell flattened, not umbilicated, generally smooth; operculum horny.
  • Above the mouth is the lid (operculum), which varies in size from a small narrow process to a large heartshaped expansion.
  • Shell semi-globular, with short spire; operculum calcareous, not spiral.
  • No ctenidium, but a pulmonary cavity; operculum with an npophysis.