TORNATELLINA. 171 



marked with faint growth-lines. Whorls 6, moderately con- 

 vex. Aperture small, ovate, about one-third the length of the 

 shell. Columella rather strongly twisted. Parietal lamella 

 strong. 



Length 3.3, diam. 1.35, aperture 1 mm. 



Length 3, diam. 1.45, aperture 1 mm. 



Bonin Islands (Ogasawara-jima) : Chichi-jima (Hirase). 

 Type no. 83007 A. N. S. P. 



This snail is very closely related to T. peponum (Gld.), but 

 it differs by the more strongly twisted columella, drawn in 

 fig. 9, for comparison with that of peponum, pi. 35, fig. 2. As 

 in T. peponum, there is, at the base of the columellar fold, a 

 callus, or as it might be termed, a small subcolumellar fold, 

 rather deeply placed, and filling the concavity of the lower 

 part of the columella. 



T. nakadai differs notably from other known forms of the 

 Japanese islands by its more slender contour, resembling T. 

 peponum, T. oblong a, and T. subcylindrica. Only the adult 

 stage is known, and it is placed in Tornatellinops provision- 

 ally, pending an examination of the neanic stage. It is 

 named in honor of Mr. Niakada, whose researches on behalf 

 of Mr. Hirase have added many species to our knowledge of 

 the Bonin Island fauna. 



28. T. HATAIANA P. & C., ii. sp. PL 37, figs. 6, 7. 



The shell is imperforate, ovate, cinnamon-colored, somewhat 

 transparent, smooth and glossy. Whorls 3^, not very con- 

 vex, aperture about half the total length; parietal lamella 

 low, about one-third of a whorl long. Columella convex in 

 front view, seen to be minutely biplicate when viewed ob- 

 liquely from below. Length 2.2, diam. 1.4, aperture 1.1 mm. 



Japan: Kita-Iwo-jima, Izu, one of the Sulphur Islands. 

 Type no. 84966 A. N. S. P. (part of 1093 coll. Hirase). 



The apex is less slender than in T. biplicata. The speci- 

 mens are probably not fully adult. In a paraneanic example, 

 fig. 7, the columella is more distinctly biplicate, and there are 

 no palatal ribs or plicae. 



