I7 8 DISCOVERY REPORTS 



Zealand demissa, but this name has been included in the synonymy of Puncturella by 

 Cotton and Godfrey (1934, South Aust. Nat., xv, No. 2, p. 54). 



Although so small the above-described species has the essential characteristics of the 

 genus. 



Family STOMATELLIDAE 

 Genus Herpetopoma, Pilsbry, 1889 

 Type (original designation) : Euchelus scabriusadus, Ad. and Ang. 

 Herpetopoma benthicola, n.sp. (Plate XLIX, fig. 13). 



Shell small, solid, conic. Whorls five, including a small depressed protoconch of if 

 whorls, consisting of one whorl smooth, globular, slightly tilted and inrolled, and a half- 

 whorl of rather distant thin axial plications. Spire tall, about i| times height of aper- 

 ture. Post-nuclear whorls with three rather narrow rounded spiral keels which are 

 crossed by crisp lamellate axials. Points of intersection raised as hollow-fronted 

 spinose scales. The uppermost spiral keel is just below the upper suture and is not 

 strongly developed, the second is situated at the middle and is much stronger, whilst the 

 third is just above the lower suture, and is the most prominent. On the base there are 

 four more spiral keels, the uppermost proceeding from the suture being strongest, the 

 other three regularly diminishing slightly towards the aperture. The interspaces be- 

 tween the spiral and axial sculpture are approximately square and the distance between 

 the spiral keels double the width of the keels. Aperture subcircular, thickened and 

 iridescent within. Columella smooth, concave with a narrow basal notch and a small 

 denticle on each side of it, followed by further weak denticles which correspond to the 

 terminal points of the external spiral sculpture. There is no umbilical chink. Colour 

 pure white, not shining, with a few scattered sepia spots which occur in no set order but 

 always at points of sculptural intersection. 



Height 3-5 mm.; diameter 3 mm. (Holotype). 



Habitat: Off Three Kings Islands, Sts. 933, 934, 260 m. 



This is a benthic relative of the littoral H. larochei, Powell, 1926, which differs in 

 being depressed conical, with more numerous axial plications, the points of intersection 

 being beaded rather than scaly. Furthermore, the littoral shell is larger and more 

 stoutly built. 



Family TROCHIDAE 



Genus Thoristella, Iredale, 191 5 



Type (original designation): Polydonta chathamensis, Hutton, 1873. Chatham Islands 



Thoristella crassicosta, n.sp. (Plate XLIX, figs. 14, 15). 



Shell small, solid, depressed conical. Spire low, less than height of aperture, sides 

 stepped. Whorls bi-angled, one angle at periphery and the other above the middle. 

 Protoconch smooth, low, first whorl rounded, but the second showing a faint indication of 

 the upper angle, which becomes a prominent feature of the post-nuclear whorls. The 



