"Subgenus Diacerion Dall, 1890.
Shell with both laminæ visible at the aperture, the axial lamina as in typical Strophiops; the parietal rather low and single at the aperture, double within, the outer branch more prominent near the aperture, the inner more prominent in the penultimate whorl, the pair prolonged inwardly for one of two whorls; whorls ample, without other internal laminæ.
Type Strophiops Dalli Maynard, Inagua Island, Bahamas. (Figure 2.) Turbo alvearia Dillwyn, and Strophia pallida Maynard, also belong here. The group is reported so far only from Inagua Island, Bahamas."