526 GASTROPODA. [Opisthobranchia. 



very high, cylindrical, rounded at the base. Suture channelled. 

 Aperture high, narrow above, considerably widened below. Outer lip 

 moderately strong, sharp, narrowly rounded above, regularly convex 

 below, the median part of the edge arched forward. Columella short, 

 oblique, with a slight fold, forming no distinct angle at the junction 

 with the lightly convex parietal wall. Inner lip spreading as a thin 

 callosity over the latter. 



Diameter, 1-5 mm. ; height, 3-2 mm. 



Animal unknown. 



Type in my collection. 



Hob. Lyall Bay, Cook Strait (A. Hamilton). 



4. Tornatina decapitata, Suter, 1909. Plate 22, fig. 31. 



Tornatina decapitata, Sut., P. Mai. S., viii, 1909, 256, pi. 11, f. 12. 



Shell small, subcylindrical, truncated at the top, very thin, vitreous, 

 smooth. Sculpture formed by exceedingly fine and dense curved 

 growth-lines. Colour white. Spire depressed, the nucleus not pro- 

 jecting above the body-whorl. Protoconch large, papillary, tilted. 

 Whorls 3, angled above, the last being the height of the shell, straight 

 at the middle, narrowed and rounded at the base. Suture canalicu- 

 late. Aperture vertical, as high as the shell, narrow above, widened 

 below. Outer lip thin and sharp, narrowly rounded and somewhat 

 ascending above, slightly advancing at the middle, regularly convex 

 at base. Columella vertical, lightly arcuate, twisted into a not very 

 distinct fold, forming a prominent angle with the parietal wall, which 

 is convex at its lower part, almost straight above. 



Diameter, 1-5 mm. ; height, 2-8 mm. 



Animal unknown. 



Type in my collection. 



Hob. Hohoura Bay (K. Buddie). 



6 Tornatina Murdoch!, n.n. Plate 22, fig. 32. 



Cylichna simplex, Murdoch and Suter, T.N.Z.I., xxxviii, 1905 (1906), 279, 

 pi. 21, f. 3, 4. 



Shell small, subcylindrical, involute, imperforate, thin, and glossy. 

 The sculpture consists of exceedingly fine growth-striae, with here and 

 there faintly marked growth-periods ; the axial striae are crossed by 

 equally fine microscopic spiral lines, in places scarcely perceptible. 

 Colour white. Spire sunken, concave, broad, and moderately deep, 

 the central nucleus somewhat raised. Protoconch papillate, tilted. 

 Whorls 4, narrowly coiled up, angularly rounded above, the last re- 

 presenting the height of the shell, subcylindrical. Suture deep, narrow, 

 channelled. Aperture as high as the shell, narrow above, expanded 

 and slightly effuse below. Outer lip almost straight, sharp, rounded 

 at both ends. Columella short, concave, with an imperceptible fold, 

 curved towards the convex parietal wall. Inner lip narrowly re- 



