The following are terms applicable to the sculpture of a molluscan shell:
Axial sculpture - Sculpture running parallel to the axis of coiling. The Axis is an imaginary line through the apex of a gastropod shell, about which the whorls are coiled.
Bead - A small hemispherical protuberance resembling a bead, similar to but smaller than a nodule.
Beaded resembling rows or strings of beads.
Growth Line(s) - fine transverse lines marking growth of the shell.
Lirate - ornamented with fine thread-like lines or grooves.
Longitudinal sculpture - following the direction of the axis of the shell.
Nodule - A rounded protuberance on the shell sculpture; larger than a bead.
Nodose, '''Nodulose''' or '''Nodular''' - bearing small rounded protuberances or tubercules.
Ornament - Can refer to surface sculpture standing out in relief on shell surface; or simply to sculpture as a whole.
Pustule(s) - very fine knob-like protrusions, smaller than a tubercule.
Reticulate - sculpture consisting of a criss-crossing network of riblets, threads, or grooves.
Rib - a strong ridge on the surface of the shell.
Riblet - smaller than a rib, but coarser than a thread.
Spiral sculpture - Sculpture following the spiral growth of the shell.
Stria (Pl. ''striae'') - a shallow incised groove.
Striate - ornamented with striae.
Thread - a very fine riblet.
Transverse sculpture - sculpture parallel to the edge of the outer lip of the Aperture .
Tubercle(s) - Elevated knob-like projections or protrusions; larger than pustule.
