168 Transactions.—Zoology. 
PurIxGNATHUS MARGINATUS, Hutton. Pl. ix., fig. s. 
Jaw arcuate, not tapering, papillate, with about 28 broad ribs. 
Dentition, 85-1-85. Teeth very minute. 
Central tooth unicuspid, longer than broad; the reflexed portion 
minute. Laterals bicuspid ; the cusps rather remote, and the reflexed 
portion small. Marginals apparently the same as the laterals, but too 
minute to make out clearly. 
flab. Greymouth (R. Helms). 
Helix REGULARIS, Pfeiffer. Pl. xi., fig. D. 
Jaw arcuate, not tapering, papillate, with about 23 broad rounded 
ribs. 
Dentition, 27-1-27. Laterals 18 or 20. 
Central tooth rectangular, the length nearly three times the breadth; 
the reflexed portion covering only a third of the base, hollowed on each 
side. Laterals oblique ; the reflexed portion covering a third of the base, 
bicuspid, the cusps close together; the inner cusp the larger and carrying 
the larger cutting point, which is long and pointed. Marginals quadran- 
gular, broader than long, with several very minute cutting points. 
Hab. Greymouth (R. Helms). 
The shell is covered with a thin epidermis which is often ciliated round 
the keel of the last whorl. 
Heux pacitosticta, Pfeiffer. 
Jaw arched, not tapering, of 21 imbricating plates covered thickly with 
papille. : ; 
Dentition, 23-1-23. All the teeth longer than broad and the reflexed 
portion very short. Central tooth unieuspid; laterals and marginals 
rather oblique, bicuspid, with small points. 
Her coneLLA, Pfeiffer. 
Jaw not seen. 
Dentition, 88-1-88. As in the last species. 
Hex srreULATA, Reeve (= alpha, Pf). Pl. xi., figs. 8. and 1. 
Animal like P. coma ; mantle subcentral, slightly reflected over the peri- 
stome ; eye-peduncles long and cylindrical; tail short, pointed, and without 
any mucous gland. Colour pale brown, with a broad slate-blue band on 
each side of the head, including the peduncles. 
Jaw slightly arched, not tapering, smooth, slightly longitudinally 
striated ; the anterior edge concave with a jagged margin. 
Dentition, 12-1-12. Laterals 8 or 4, 
Central tooth rectangular, as broad as long ; the reflexed portion tri- 
cuspid, the middle cusp reaching two-thirds of the length. Laterals 
tricuspid, the side-cusps constricted on their outer sides, the middle cusp 
