Surface appears smooth, but microscopic striae sometimes detectable (only very slight indications of spiral striae found on any shells examined by author).
1: strongest pair of striae may combine to form spiral groove (cord) a short distance below periphery near where costae terminate.
2: additional spiral cord.
3: medial dividing line on sole allows longitudinal folding to grasp strands of filamentous algae, and allows independent movement on either side of foot when in motion.
4: when magnified, narrow translucent slit may be detected in single white line in cephalic tentacle.
5: foot constriction enables transverse folding of narrow foot.
6: black osphradium that tests quality of inhalent water before it reaches ctenidium (gill).
7: brown lines absent from spaces between white costae on this specimen, but some brownish and green debris /growths in spaces.
8: encrustation of stony alga Titanoderma (syn. Lithophyllum)