The middle layer of the shell of a mollusc, consisting of crystalline calcite or aragonite.
More example sentences
- The prismatic layer is the middle layer and is composed of thin blocks of a prism-like calcium carbonate, which are oriented perpendicular to the mantle and the other two layers.
- Thinner extensions from the prismatic layer in Pseudobigalea crista also form comarginal ridges.
- As a result, it has been difficult to identify detailed or minute shell structures embedded in the thick prismatic layer or secondary thickening at the shell posterior.
Definition of prismatic layer in:
- The US English dictionary