GASTROPODA. 155 



1. Cirsonella densilirata, Suter, 1908. Plate 34, fig. 2. 

 Cirsonella densilirata, Suter, P. Mai. S., viii, 26, pi. 2. f. 13. 



Shell small, turbinate, subdiaphanous, slightly shining, perforated. 

 Sculpture consisting of numerous fine microscopic spiral lirse. Colour- 

 white. Spire depressed conoidal, outlines convex, lower than the 

 aperture. Protoconch of 2 convex smooth whorls ; yellowish-white. 

 Whorls 3i, rapidly increasing, convex, periphery of last whorl rounded. 

 base convex, with an impressed umbilical area. Suture not much 

 impressed. Aperture circular, oblique, inside microscopically lirate. 

 Peristome continuous, thick. Columella arcuate, slightly expanded to- 

 ward the narrow perforation, sometimes partly concealing it. Oper- 

 culum horny, multispiral ; nucleus central. 



Diameter, 2-25 mm. ; height, 1-75 mm. 



Animal unknown. 



Type in my collection. 



Hab. Snares, in 50 fathoms (type) ; Bounty Islands, in 50 fathoms 

 (Captain Bollons). 



Remark. The species is very closely related to the Tasmanian 

 C. Weldii, Ten. -Woods, which, however, is smooth, having a few 

 spiral lira? around the umbilicus only. 



2. Cirsonella granum, Murdoch and Suter, 1906. Plate 34, fig. 3. 



Cirsonella <j>-rnnii. M. & S., T.N.Z.I.. xxxviii. 1905 (1906). 300, pi. 27. 

 f. 50, 51. 



Shell minute, turbinate, umbilicate, smooth and glossy. Sculp- 

 ture absent, except for the microscopic growth-striae. Colour white, 

 fresh specimens vitreous. Spire conoidal. small, height a little less 

 than that of the aperture. Protoconch consists of 1 whorl, which is 

 smooth and rounded. Whorls 4, much rounded, the last propor- 

 tionately large ; base convex. Suture deep. Aperture subcircular, 

 broadly angled above, but little excavated by the body-whorl. Outer 

 lip sharp, forming a half-circle with the basal lip. Columella concave 

 and reflected, thickened. Inner lip spread as a thin layer upon the 

 parietal wall. Umbilicus with its area small and with a somewhat 

 sharply defined margin, the perforation narrow. 



Diameter, 1-75 mm. ; height, 1-75 mm. 



Type in the Dominion Museum, Wellington. 



Hab. About 15 miles outside Great Barrier Island, in 110 fathoms. 



Remark. It is a much smaller shell than C. neozelanica, more 

 globular, with the aperture more circular, and better and differently 

 defined umbilical area. 



3. Cirsonella neozelanica, Murdoch, 1899. Plate 34, fig. 4. 



Cirsonellfi iinr.ilnniro, Murdoch, P. Mai. S., iii, 320, pi. 1(5, f. 2-(5. 

 Shell small, ovate, perforate, semitransparent. There is no sculp- 

 ture, except microscopical fine close growth-striae. Colour horny- 

 fuscous. Epidermis very thin, faintly shining. Spire conical, a little 



