Hurron 

The Pliocene Mollusca of New Zealand. 39 
TROPHON CHEESEMANI, Hutton, Trans. N.Z. Inst. Vol. XV. p. 131 (Polytropa). 
(Plate vi. fig. 4.) 
Shell small, fusiform. Whorls five ; those of the spire small, with a single 
spiral rib ; body whorl large with five spiral grooves between the ribs, the ribs 
broad and smooth, the grooves narrow and transversely striated. Aperture 
moderate, contracted in front into a short, open, slightly twisted canal; four 
or five short, well developed teeth inside the outer lip. Length 15mm. ; 
breadth 9m. 
Locality. —W anganui. 
TropHon expansus, Hutton, Trans. N.Z. Inst. Vol. XV. p. 410. 
(Plate vi. fig. 5.) 
Shell ovate, spire moderate acute. _Whorls five or six, spirally grooved, the 
grooves narrower than the ribs; about 26 grooves on the body whorl, crossed by 
undulating lamine of growth worn smooth. Aperture ovate, wide, slightly 
angled behind ; outer lip expanded; columella rounded, with a small posterior 
canal; anterior canal very short and recurved. Length 20mm.; breadth 10mm. 
Locality.—Wanganui, Petane, Matapiro. 
TropHon pLeBetus, Hutton, Cat. Marine Moll. of. N.Z. p. 9 (/7wszs). 
(Plate vi. fig. 6.) 
Shell small, fusiform. Whorls six or seven, spirally grooved and finely 
longitudinally plaited. Aperture oval, anterior canal moderate, bent slightly to 
the left ; outer lip grooved in the adult. Length 21mm.; breadth 10mm. 
Locality.—Wanganui, Petane, Matapiro. 
TropHon puopecimus, Gray, in Dieftenbach’s ““New Zealand,” IT. p. 230 (4 sus) ; 
Kalydon duodecimus, Hutton, Trans. N.Z. Inst. Vol. XVI. p. 220. 
(Plate VI. fig. ie) 
Shell small, fusiform, with about twelve broad rounded longitudinal ribs, 
which are crossed on the body whorl by about 12 to 18 narrow spiral ribs. 
Aperture oval; canal moderate, nearly straight. Length 14mm.; breadth 6mm. 
Locahty.—W anganui, Petane, Matapiro. 

