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PROCEEDINGS OF THE NATIONAL MUSEUM 





Figure 52. — Zaptyx (Zaptyx) rehderi, new species: a, Ventral side of holotype; h, dorsal 

 side of a paratype, opened to |show the inner structure; c, right side of a paratype; d, 

 clausilium (X 5). 



Aperture including the sinulus broadly ovate. Sinulus not high, 

 separated by the superior lamella only. Peristome continuous, whit- 

 ish, thin, narrowly reflexed, the upper part free from the preceding 

 whorl. 



Superior lamella short, compressed, vertical, reaching the margin, 

 separated widely from the spiral lamella, which is scarcely visible in 

 the aperture because it reaches from the ventral to the dorsal side. 



Inferior lamella visible in a frontal view as a low fold only in the 

 lower half of the aperture, where it reaches the margin in the right 

 corner. In an oblique view it is visible, increasing in height as it 

 ascends vertically inward, the edge considerably thickened. In a 

 lateral position, where it leaves the columella and runs along the 

 parietal wall, the inferior lamella is abruptly lower, and at last ends 

 as the spiral lamella in the middle of the ventral side. 



Subcolumellar lamella deeply immersed, not visible in the aperture. 

 The closing apparatus lies lateroventrally. Principal plica less than 



