In the Auriculidae the aperture is denticulated.
They are usually preserved as branching or unbranching carbonized bodies, tree-like, leaf-like or rod-like in shape, their edges regularly toothed or denticulated.
But its altitude does not exceed 10,000 ft., and its steep rocky slopes meet in a sharp, denticulated crest.
Terrestrial and usually littoral; genital duct monaulic, the penis being connected with the aperture by an open or closed groove; shell with a prominent spire, the internal partitions often absorbed and the aperture denticulated.