parietal lamina

The columellar margin is dilated, not closing the perforation, expanded above in a parietal lamina.

The aperture is very oblique, rounded, with continuous slightly expanded peristome, and having several teeth on the outer lip and an entering parietal lamina.

The parietal lamina (lamina parietalis) is far more extensive than the visceral, extending upward for some distance in front and on the medial side of the cord, and reaching below the testis.