202 Transactions. —Z oology. 
P. PLANULATA, Hutton (1888). 
Spire slightly elevated; narrowly umbilicated, the umbilicus covered ; 
whorls closely ribbed; ribs about 40 in the tenth of an inch. Horny 
brown sometimes clouded with rufous. Diameter :15 inch. Dentition, 
11-1-11 
North Island.—Auckland (Cheeseman). 
South Island.—Greymouth (Helms). 
P. MIRANDA, Hutton (1883). 
Spire convex; very finely ribbed, ribs about 50 in the tenth of an 
inch ; imperforate or very narrowly umbilicated. Pale horny banded with 
chestnut on the upper surface and tessellated with the same colour below. 
Diameter ‘16 inch. Dentition, 17-1-17. 
South Island.—Greymouth (Helms). 
Genus’ Therasia, Hutton. 
Shell conoidal, depressed, periphery sub-carinated ; sub-perforate or 
narrowly perforate; whorls smooth, striated, or with membranous plaits. 
Jaw with flat ribs. Marginal teeth broad, usually with several points. 
A. Sub-perforate. 
T. ceLinDa, Gray (1849). 
Whorls with distant membranous plaits, about 10 in the tenth of an 
inch. Pale brown. Diameter ‘14 inch. Dentition, 18-1-18. 
North Island.—Auckland (Greenwood, Cheeseman). 
T. varer, Hutton (1888). 
Whorls strongly striated. Yellowish horny, obscurely marked with 
reddish. Diameter ‘25 inch. Dentition, 26-1-26. 
South Island.—Dunedin (F.W.H 
T. ormeLza, Pfeiffer (1854). 
Umbilicus very narrow. Whorls delicately striated; periphery angu- 
lated. Horny with obscure reddish streaks. Diameter ‘40 inch. 
North Island.—Auckland (Cheeseman). 
South Island.—Dunedin (F.W.H.). 
B. Narrowly umbilicated.. 
T. ramora, Hutton (1883). 
Conical ; irregularly plaited. Brownish horny. Diameter ‘17 inch. 
North Island.—Auckland (Cheeseman). 
IT. ruarsa, Hutton (1888). 
Irregularly coarsely striated. Pale horny, variously streaked with 
brown. Diameter °35 inch. Dentition, 27-1-27. 
North Island.—Auckland (Gillies) ; Napier; Wellington (T. W. Kirk). 
South Island.—Waipara (Haast, Chilton); Waitaki, Queenstown, Dun- 
edin and Lake Guyon (F.W.H.); Waiau, Southland (G. M. Thomson). 
