The middle layer of the shell of a mollusc, consisting of crystalline calcite or aragonite.
〔动〕（软体动物贝壳的）柱状层，棱柱层
Example sentencesExamples
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.
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.
Besides, the aragonitic shell is made up of two oriented layers: an irregular spherulitic prismatic layer and a fine complex crossed lamellar layer.
This thin, prismatic layer was deposited too far from the shell margins to be interpreted as likely pallial myostracum.
Definition of prismatic layer in US English:
prismatic layer
noun
Zoology
The middle layer of the shell of a mollusk, consisting of calcite or aragonite.
〔动〕（软体动物贝壳的）柱状层，棱柱层
Example sentencesExamples
Thinner extensions from the prismatic layer in Pseudobigalea crista also form comarginal ridges.
This thin, prismatic layer was deposited too far from the shell margins to be interpreted as likely pallial myostracum.
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.
Besides, the aragonitic shell is made up of two oriented layers: an irregular spherulitic prismatic layer and a fine complex crossed lamellar layer.
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.