342 GASTROPODA. [Pectmibranchia. 



15. Odostomia vestalis, Murdoch, 1905. Plate 17, fig. 4. 



Odostomia vestalis, Murdoch, T.N.Z.I., xxxvii, 1904 (1905), 227, pi. 8, f. 20. 



Shell small, slender, smooth, polished, and having a somewhat 

 loosely coiled appearance. Sculptured with minute irregular growth- 

 lines, crossed by irregular microscopic striae, the latter only indi- 

 cated here and there. Colour white. Spire subulate, about twice the 

 height of the aperture, sometimes a little more ; outlines faintly 

 convex. Protoconch heterostrophe, globular, slightly obliquely tilted, 

 nucleus lateral. Whorls 6, rapidly but regularly increasing, lightly 

 convex ; base flatly rounded. Suture impressed, shallow, and lightly 

 submargined. Aperture pyriform, narrowed and effuse below. Outer 

 Up thin, sharp. Columella arcuate, with a small oblique plait, rather 

 deep within the aperture. Inner lip lightly reflected, and spreading 

 thinly over the parietal wall. Umbilicus closed. Operculum un- 

 known. 



Diameter, 1-6 mm. ; height, 4-3 mm. 



Animal unknown. 



Type in the Dominion Museum, Wellington. 



Hob. Whangaroa Harbour, type (C. Traill) ; near Channel Island, 

 Hauraki Gulf, in 25 fathoms ; Banks Peninsula (Iredale). 



Subgen. 2. EVALEA, A. Adams, 1860. 



Evalea, A. Ad., A.M.N.H., vi, 1860, 22, 417. Type : E. elegans, A. Ad. 

 Ondina, Folin, 1870. Auriculina, Gray, 1847. Ptychostomon, Locard, 

 1886. 



Shell with the axial ribs absent, represented by lines of growth 

 only, with spiral markings consisting of many usually subequally 

 and universally distributed impressed lines. 



KEY TO SPECIES. 



A. Spire about twice the height of the aperture, whorls conspicuously 



spirally lirate . . . . . . liririncta. 



B. Spire about 1| times the height of the aperture, spiral sculpture 



not conspicuous. 



a. With numerous flat spiral threads, suture superficial. . .. impolite, 



aa. With fine microscopic spiral striae and a few more prominent 



spiral cords on the body-whorl, suture deep . . . . chordata. 



16. Odostomia chordata, Suter, 1908. Plate 17, fig. 5. 

 Odostomia (Evalea) chordata, Suter, T.N.Z.I., xl, 1907 (1908), 348, pi. 27, f. 5. 



Shell small, elongate-ovate, subperforate, slightly scalar, rather 

 thin, polished. Sculpture consisting of very fine and close micro- 

 scopic striee, and in addition a few subequidistant flat spiral cords, 

 distinct only on the body-whorl ; their number is about 9, and those 

 on the middle of the whorl are less conspicuous ; the growth-lines 

 are vertical, close and fine, but some are more prominent. Colour 

 white. Spire elevated conic, about H times the height of the aper- 



