Ophicnrdelus.] GASTROPODA. 591 



large, ventricose, convex, attenuated towards the base, which is 

 flat or somewhat excavated inside the umbilical keel. Suture linear, 

 uneven. Aperture subvertical, narrowly ovate, angled above. Outer 

 lip lightly convex, sometimes with an outer varix, smooth inside, 

 strengthened inside by a light callus on the lower half. Columella 

 vertical, with a sharply elevated horizontal plait at the junction with 

 the parietal wall, and a second more or less oblique and not so sharp 

 plait about the middle between the upper plait and the basal lip. 

 Inner Up broadly extended between the 2 plaits, and as a thin shining 

 glaze over the parietal wall. Some specimens show an indistinct 

 umbilical chink. 



Diameter, 7 mm. ; height, 13-5 mm. (type). Diameter, 5-5 mm. ; 

 height, 10-5 mm. (New Zealand specimen). 



Animal moderately large ; tentacles fusiform, not sharply pointed, 

 sometimes a little inflated, brown, annulated with black, eyes at their 

 inner bases : muzzle elongated ; foot oval, a little pointed, without 

 bifurcation ; colour dark brown, the sides lighter. (Q. & G.) 



Dentition. Hutton. T.N.Z.I., xvi, 212, pi. 11, f. 1. 



Type in the Mus. Hist. Nat., Paris. 



Hab. North Island and the northern part of the South Island, 

 in brackish water and mangrove swamps ; common. Also Tas- 

 mania, Australia, and New Caledonia. 



Remarks. The type of M. costellaris, Ad., was collected in New 

 Zealand by Strange. 



Genus 2. MARINULA, King, 1831. 



Marinula, King, Zool. Journ., v, Sept. 1831, 344. Type : Marinula pepita, 

 King. 



Animal with the foot simple inferiorly, without a transverse groove. 



Shell ovato-oblong, imperforate, solid, smooth ; spire short, conic ; 

 aperture subovate ; columella flattened, with 3 plaits, the upper one 

 very large, obliquely descending, the lower two smaller and less ob- 

 lique ; outer lip posteriorly sinuated, simple, acute. 



Distribution. Pacific, South America, Australasia. 



Fossil in the Eocene of Paris. 



1. Marinula Filholi, Hutton, 1878. Plate 24, fig. 2. 



Marinula Filholi, Hutt., J. de Conch., xxvi, 1878, 42 ; T.N.Z.I., x, 297 ; 

 M.N.Z.M., 34. 



Shell ovato-oblong, smooth, brown, with 3 columellar plaits. Fiue 

 oblique growth-lines are the only sculpture. Colour purplish-brown 

 or fulvous, aperture light brown inside, peristome and the plaits 

 white. Epidermis very thin, not shining. Spire short, conic, about 

 three-quarters the height of the aperture ; outlines convex. Proto- 

 conch globose, smooth, mostly eroded. Whorls 5 to 6, the last large, 

 somewhat ventricose, the upper volutions lightly convex. Suture 



