GASTEROPODA 195 



The suture is margined above by the upper edge of a third cord, which is three parts 

 covered by the succeeding whorl. On the body whorl there are these three spiral cords 

 plus three more on the base, the sixth, which borders the inner lip, being rather in- 

 distinct. Aperture small, oblique-oval, very heavily variced externally. 



Height 1-5 mm.; diameter 1 mm. (Holotype). 



Habitat: Off Three Kings Islands, St. 934, 92 m. 



This species is remarkable for its solidity, squat shape and heavy sculpture. 



Genus Prumerelina, Powell, 1926 

 Type (original designation) : Promerelina crosseaformis, Powell 



Promerelina tricarinata, n.sp. (Plate LII, fig. 11). 



Shell very small, clathrate, white. Whorls four, including a typical protoconch of i\ 

 convex whorls sculptured with six minutely granular spiral ridges. Post-nuclear spire 

 whorls with three strong spiral keels, crossed by widely spaced thin axials which become 

 weakly nodulose at points of intersection. Rectangular interspaces much broader than 

 high. Spire tall, about if height of aperture. Whorls deeply indented at suture, and 

 sharply angled at two-thirds their height by the uppermost keel, which is separated 

 from the upper suture by a broad slightly concave shoulder. The axials number twelve 

 on the penultimate whorl. Body whorl with the addition of a single very strong and 

 sharp basal keel which emerges from the suture. Remainder of base smooth and con- 

 cave except for a strong fold which borders the outside of the inner lip callus, although 

 separated from it by a narrow groove. Aperture oblique-oval. Peristome continuous, 

 externally duplicated by a broad varix. 



Height 1-4 mm.; diameter o-8 mm. (Holotype). 



Habitat: Off Three Kings Islands, St. 934, 92 m. 



This makes the third known species of the genus. 



Genus Nobolira, Finlay, 1926 

 Type (original designation) : Lironoba polyvincta, Finlay. Lower Miocene, New Zealand 



Nobolira cochlearella, n.sp. (Plate LII, fig. 15). 



Shell small, elongate-conical, thin and fragile; sculptured with narrow spiral ridges. 

 Whorls five, including a large globose protoconch of two whorls which is sculptured with 

 six, regular, fine spiral lirae, and marked off from the post-nuclear whorls by a thin varix. 

 Spire tall, subgradate, about if times height of aperture. Post-nuclear whorls to pen- 

 ultimate with four spiral ridges, increasing to six at the commencement of the body 

 whorl, and with five additional spirals on the base. On the spire whorls the interspaces 

 are twice the width of the ridges, but they are less than their own width on the base. 

 Aperture ovate, oblique. Peristome continuous; outer lip strengthened behind by a 

 slight varix. Colour white, translucent. 



Height 1-9 mm.; diameter 0-9 mm. (Holotype). 



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



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