Polin-ices.} GASTROPODA. 291 



conch rather large, depressed convex, of 1J smooth whorls. Whorls 

 4|, narrow, flatly rounded, of gradual increase to the last, which is 

 disproportionately large, especially toward the mouth. Suture strong, 

 slightly channelled, almost quite horizontal. Aperture large, oval, 

 very little oblique, and rather straight, scarcely pointed above ; it is 

 more than two-thirds of the whole height. Outer lip sharp but strong, 

 patulous throughout. Inner lip straightish, but slightly concave in 

 its whole length ; it is expanded at the labial callus, which is thick, 

 with a labial pad. The front of the columella is thickened and flattened 

 back on the very indistinct circumumbilical carina. Umbilicus is a 

 rather coarse, pervious, smallish, round hole, hardly encroached on 

 at all by the inner lip ; it is barely funiculate. Operculum mem- 

 branaceous, thinnish, of a yellow colour, with a dark-maroon outer 

 edge, which does not quite coil into the centre. (Watson.) 



Diameter, 6-25 mm. ; height, 6-75 mm. (type). Diameter, 8-5 mm. ; 

 height, 9 mm. (type of P. vitreus, Hutt.). 



Animal unknown. 



Type in the British Museum ; of P. vitreus, in the Dominion 

 Museum, Wellington. 



Hob. North-east from New Zealand, in 700 fathoms, Chall. Stat. 

 169 (type) ; Stewart Island (type of P. vitreus) ; Chatham Islands ; 

 Bounty Islands, in 50 fathoms (Captain Bollons). 



Fossil in the Pliocene. 



Genus 3. AMPULLINA (Lamarck), Bowdich, 1822. 



Ampullina, Bowdich (as of Lam.), Elem. Conch., i, 1822, 31. Type : 

 Ampullaria de-pressa, Lam. ; not of Sow. Ampullinopsis, Conrad, 1865. 

 Megatyloius, Fischer, 1885. Amauropsis, Morch, 1857. Globulus, J. deC. 

 Sowerby, 1835 ; not of Schumacher, 1817. Euspira (sp.), Desor and 

 Agassiz, 1842. Globularia, Swainson, 1840. Crommium, Cossmann, 1888. 

 Amauropsella, Chelot, 1885. Amaurdlina, Fischer, 1885. Ampullina, 

 Bowdich : W. H. DaU, U.S. Geol. Survey, Professional Paper 59" The 

 Miocene of Astoria and Coos Bay, Oregon," 1909, 89. 



Shell naticiform ; umbilicus without a funiculus, open or closed 

 by a callosity ; aperture large ; outer margin sinuous, produced at 

 the middle ; umbilical region generally limited by a spiral rib or Limb 

 more or less developed ; columella-border curved, typically S-shaped. 



Fossil in the Tertiary. 



KEY TO SPECIES. 



A. Two low rounded ribs on the umbilical area . . . . . . venusta. 



B. Umbilical area without ribs . . . . . . . . . . undulata. 



1. Ampullina undulata, Hutton, 1885. Plate 15, fig. 17. 



Sigaretus undulatus, Hutt., T.N.Z.I., xvii, 1884 (1885), 318, pi. 18, f. 11 > 

 Plioc. M., 55, pi. 7, f. 41 ; Webster, T.N.Z.I., xxxvii, 280. * 



Shell moderately large, subglobose, nearly smooth, thin and fragile, 

 umbilicus sealed up. Sculpture : Fine oblique and flexuous growth- 

 lines, crossed by delicate, close, undulating spiral lines, more distant 



10* 



