1S75.] G-. & H. Nevill — Desertions of new Marine Mollusca. 97 



transversely indistinctly striated, a groove below the suture of the upper 

 whorls, becoming obsolete near the last whorl ; columella simple and twisted, 

 outer lip acute, slightly emarginate at the top, aperture striated within. 



Long. 5, diam. If mil. 



Mauritius. Not common. 



Zapea polita, n. sp., PI. VIII, Fig. 5. 



Shell small, slenderly fusiform, attenuated at both ends, perfectly smooth, 

 glistening spire contorted, nearly but not quite as long as the last whorl ; 

 white, with two bands of irregular opaque white flakes on each whorl (four 

 on the last) ; whorls 6 (the figured specimen has had the first broken off), 

 the last striated at its base, outer lip remarkably thick and bent inwards, 

 making the aperture peculiarly contracted. 



Long. 3^, diam. If mil. 



Mauritius, — rather scarce. 



Easily distinguished by the absence of sculpture and by its remarkably 

 contracted aperture from its nearest ally, Z. ornata, Pease. Z. purpurea, H. 

 Ad. from New Hebrides is also found at Mauritius. 



Zapea semisculpta, n. sp., PI. VIII, Figs. 6 — 7. 



Shell narrowly lanceolate, turreted, spire a little longer than the last 

 whorl, apex pointed ; horny-brown throughout ; whorls 7, the three first 

 without sculpture, the rest longitudinally thickly ribbed, ribs about twics 

 as broad as their interstices (in this respect our figures are slightly at fault), 

 obsolete on the back of the last whorl, which is transversely striated 

 at its base ; a sharply defined callosity covers the columella, outer lip 

 scarcely thickened or reflected, not as long as the columella, slightly 

 emarginate at junction with the last whorl ; aperture narrow and contracted, 

 as wide at the top as at the base. 



Long. 3, diam. 1 mil. 



This species was dredged by Mr. Blanford at Cape Negrais, off the 

 coast of Burma. 



SlSTETJM VENTEICOSTTLUM, n. sp., PI. VIII, Fig. 16. 



Shell small, ovately ventricose, very gibbous in the middle, thick, solid, 

 abruptly attenuated at base ; spire short, acutely pointed, about half the 

 length of the last whorl ; white, here and there stained with pale brown ; 

 whorls 7, the first four very small, embryonal, without sculpture, the next 

 has two rows of unequal granules, the lower row somewhat pointed and much 

 the larger ; the last whorl widely excavated at the suture, with a row of pro- 

 minent granules, rounded beneath with distant, somewhat indistinct longi- 

 tudinal ribs, transversely rather distantly keeled, forming slightly pointed 

 granules where they intersect the ribs, the interstices under a lens very mi- 



