2i8 DISCOVERY REPORTS 



This adds a genus to the New Zealand fauna. Finlay (1926, Trans. N.Z. Inst., lvi, 

 p. 254) mentioned the presence of undescribed species of Nepotilla in New Zealand 

 waters. The genus is strongly represented in Tasmanian and Southern Australian 

 waters. 



Genus Stilla, Finlay, 1926 



Type (original designation) : Mangilia flexicostata, Suter 



Stilla paucicostata, n.sp. (Plate LVI, fig. 11). 



Shell close to that of flexicostata but proportionately wider and with fewer and stronger 

 axial ribs. Spire of same height as aperture plus canal. Post-nuclear sculpture of strong 

 blunt oblique wide-spaced axials and a few weak spiral cords. On the body whorl there 

 are thirteen axials, compared with eighteen in flexicostata. The spiral cords number two 

 on the spire whorls and three on the last whorl, the lowest proceeding from the suture. 

 The axials become faint at the sutural cord and rapidly fade out over the base. Proto- 

 conch, sinus and other characteristics as in the typical species. 



Height 1-7 mm.; diameter 0-95 mm. (Holotype). 



Habitat: Off Three Kings Islands, St. 933, 260 m. 



Genus Mitrithara, Hedley, 1922 

 Type (original designation) : Columkella alba, Petterd 

 Mitrithara granulifera, n.sp. (Plate LVI, fig. 9). 



Shell rather small, white, solid, biconic. Whorls four, including a smooth rounded 

 protoconch of i| whorls. Spire a little less than height of aperture. Outline of whorls 

 lightly convex, base straight, tapering but not concave. Post-nuclear whorls sculptured 

 with the characteristic close revolving cords, which are granulated by axial threads. The 

 spiral cords number seven on the spire whorls and thirty on the body whorl and base, 

 becoming much more closely spaced over the fasciolar portion. Aperture long and 

 narrow, sides parallel medially. Canal wide and short. Sinus broad and shallow, situ- 

 ated just below the suture. Columella straight with two closely spaced weak medially 

 situated plications. Outer lip thin at edge, becoming thicker within the aperture but 

 not variced. 



Height 3-85 mm.; diameter i-8 mm. (Holotype). 



Habitat: Off Three Kings Islands, St. 933, 260 m. 



This species appears to be more closely related to Australian species such as the 

 genotype and proles, Hedley, 1922, than to gemmata (Suter, 1908) from southern New 

 Zealand. 



Mitrithara regis, n.sp. (Plate LVI, fig. 10). 



Shell rather small, ovate, solid, white, spirally grooved and axially costate. Whorls 4J. 

 Spire about two-thirds height of aperture. Protoconch smooth, dome-shaped, of i\ 

 whorls, followed by a brephic stage of closely spaced axials. First post-nuclear whorl 



