172 GASTROPODA. 



Sect. 1. PELORONTA, Oken, 1815. 



Peloronta, Oken, Zool., 1815, 360. Type : N. peloronta, L. Tenure, Gray. 

 P.Z.S., 1858, 92. 



Columellar lip nearly smooth, its margin strongly dentate, outer 

 lip dentate within. 



1. Nerita melanotragus, E. A. Smith, 1884. Plate 39, fig. 10. 



Nerita melanotragus, E. A. Smith, Zool. Coll., H.M.S. " Alert," 1884 (1, viii), 

 69. N. nigra, Gray, DieiT. N.Z., 240, not of Dillwyn, 1817. N. atruta, 

 Chemn. : Reeve, Conch. Icon., ix, 1855, f. 16, not of Chemnitz nor 

 Deshayes. N. saturata, Hutton, P.L.S. N.S.W., ix, 1884 (19, viii), 354. 

 N. punctata, Q. & G. : Watson, Chal. Rep., xv, 132, not of Quoy and 

 Gaimard. N. alrata, Reeve : Tryon, Man. Conch. (1), x, 26, pi. 8, f. 40. 

 A T . melanotragus, Smith: Hedley, P.L.S. X.S.W., 1900, 500; Suter, 

 T.N.Z.I., xxxviii, 324. 



Shell moderately large, solid, globose-oval, black. Sculpture con- 

 sisting of irregularly disposed spiral grooves, which are narrow and 

 shallow, having much broader interstices between them ; growth- 

 strife fine, but with more or less distant well-marked periods of rest. 

 Colour uniformly black, sometimes bluish-black. Epidermis solid^ 

 more or less shining. Spire low, rounded. Protoconch small, almost 

 flat, smooth, greenish. Whorls 3, convex, very rapidly increasing,. 

 the last descending in front ; base convex, no umbilical depression. 

 Suture superficial. Aperture oblique, semicircular, white or bluish- 

 white within. Outer lip solid, sharp, black-edged, more or less dis- 

 tinctly denticulate. Columella oblique, slightly concave, with 2 or 3 

 denticles in the middle. Inner lip forming a broad white and shining 

 callus, which bears slight wrinkles and pustules. Operculum granulate 

 on the outer face, pale purple, with 2 spiral bands of black. 



Diameter, 23-35 mm. ; height, 20-31 mm. 



Dentition. Kutton, T.N.Z.I., xv, 123, pi. 14, f. H. 



Type in the British Museum. 



Hob. North Island, under stones between tide-marks ; Ker- 

 madec Islands ; Australia and Tasmania. Brought to England by 

 Captain Cook. 



Maori. Ngarahutatawa (fide Captain Bollons). 



Fam. COCCULINID/E, Ball. 



Animal with a prominent head and muzzle, the males with an 

 intromittant organ at the base of the right tentacle ; a single lamellose 

 asymmetrical gill between the under-surface of the mantle and the 

 upper surface of the body from a point above and behind the head, 

 extending around toward the right, and even backward on the right 

 side ; attached only at its base. Eyes wanting in the known species. 

 Anus anterior, opening in a papilla above and behind the head. 

 Mantle-margin and sides of foot plain, without epipodial papillae or 

 processes, but they are sometimes present behind. Radula with a 



