STJTfiR : ON MOLLUSCA FROM NEW ZEALAND. ZO 



with the periphery and base rounded. Suture deep. Aperture roundly 

 ovate, angled above. Peristome continuous, sometimes thickened by 

 a radiate riblet. Columella arcuate, very little expanded. Perforation 

 narrow, partly hidden by the columella. Diam. 1, height r5 mm. 



Eah. — Titahi Bay, Cook Strait, in sand (Miss M. Mestayer). 

 C. Angeli, T.-W., conica, Wats., and crebresculptum, Tate, are nearly 

 allied species. Type, from the Pliocene, in the Canterbury Museum, 

 Christchurch. 



8. Ctclosteema eumorpha, n.sp. PI. II, Figs. 7-9. 



Shell very small, turbinate, umbilicate, translucent white, spirally 

 distantly ribbed, and radiately striate. Sculpture consisting of five 

 prominent spiral riblets, the first just above the periphery, a low and 

 indistinct spiral riblet on the last whorl outside the suture, and some- 

 times a fine riblet bordering the funnel-shaped umbilicus; radiate 

 sculpture formed by distinct threads, which are equidistant, slightly 

 directed backward, the interstices wider than the threads. Colour 

 white. Spire depressed conoidal, lower than the height of aperture. 

 Protoconch minute, spherical, of one whorl only. Whorls 3, regularly 

 increasing, convex, the last flattened between the suture and the first 

 spiral riblet, periphery rounded ; base convex. Suture impressed. 

 Aperture oblique, circular. Peristome continuous, smooth inside, 

 ornamented on the outside by spiral sculpture. Columella arcuate, 

 strong, not reflexed. Umbilicus rather narrow, deep. Diam. maj. 

 r?, min. r4 mm. ; height 13 mm. 



Sab. — Near the Snares Islands, in 50 fathoms (Capt. J. Pollons). 



This species is allied to the South Australian C. delectaiile, Tate, in 

 which, however, the spiral riblets are more numerous and less pro- 

 minent, the umbilicus much wider, perspective. Type in my collection. 



9. Cyclostkema lissum, n.sp. PL II, Figs. 10, 11. 



Shell minute, discoidal, thin, smooth, umbilicated. Sculpture : to 

 the naked eye the shell appears to be quite smooth, but a powerful 

 lens reveals subequidistant, strongly undulating radiate threads ; there 

 is no spiral sculpture visible. Colour yellowish-white. Spire flat, the 

 nucleus only being slightly raised. Protoconch of one smooth whorl, 

 which is convex and the first half very often slightly elevated. 

 Whorls 2, the last flatly convex above, periphery and base rounded. 

 Suture impressed. Aperture subcircular, a little angled above. 

 Peristome continuous, sharp, outer lip advancing and producing a dis- 

 tinct notch at the suture. Columella arcuate, slightly thickened. 

 Umbilicus moderate, open. Diam. 1, height 0'6 mm. 



Hab. — Lyttelton Harbour, on seaweeds (H. S.); Titahi Bay, Cook 

 Strait (Miss M, Mestayer). 



This species is well characterized by its minuteness, the few whorls, 

 and the microscopic radiate sculpture. Type in my collection. 



10. Ctclosteemella Neozelanica , n.sp. PI. II, Fig. 12. 



Shell small, planorboid, radiately ribbed, broadly umbilicate. Sculp- 

 ture consisting of close, sharp, radiate riblets, the smooth interstices of 



