Marwick.—WNaticidae and Naricidae of New Zealand. 559 
of channel. In S. suturalis and S. is the lip is J— though 
gently retracted for a considerable distane 
It is possible that another specific division can be made for those 
shells with a narrower sutural channel than the type. This narrowing is 
3. Genus User Humphreys, 1797* (= Polinices Montfort, 1810). 
Shell ovate to subcylindrical; sutures tangential; aperture with 
thick parietal callus coalescing with the funicle and invading the umbilicus, 
hich is sometimes completely filled, sometimes left widely open; oper- 
culum corneous. 
T Nerita mammilla Linné. 
KEY TO SPECIES. 
huttoni : very large, sometimes ovate, see seid subcylindrical with a low spire, 
umbilicus closed or shallow, never penet: 
sagenus : moderate size, roundly oval, dathonsd umbilicus wide, variable; aperture 
greatly inclin 
ucronatus : moderate size, longitudinally oval, apex mucronate, umbilicus closed, 
callus very thick. 
— т : large, subcylindrical, summit flat; callus enormous, filling suture and 
umbilicus 
us: moderate size, ovate; umbilicus closed ; callus fairly thick with two con- 
verging grooves, interspace lo lobed. 
unisulcatus ; moderate size, ovate; umbilicus closed ; callus with only one groove at 
, base, close and and parallel to apertural margin. 
small ovate; umbilicus closed ; callus like wnisulcatus ; nucleus of 
protoconch minute 
large, ovate ; umbilicus open below; callus joined to parietal wall for 
full чүш, no groo 
S олй umbilicus open below; callus projecting in а 
pro at ae over c ea enis marked hy deep groove 
waipipiensis : large, broadly ovate ; umbilicus with large opening left between parietal 
rge, broadly ovate; umbilicus widely open, funicle narrow ; callus not 
advancing fa far down and асі in а lo 
arge, ovate ; umbilicus almost closed by callus and wide funicle, leaving 
finlayi uy large ovate; callus rather narrow, xis often filling umbilicus, which 
ITOW ; r margin of aperture strongly sin 
тош: уегу peri ovate; callus with parietal side straight ; umbilicus generally 
a shallow groove 
kaawaensis : very small, broadly ovate; callus with parietal side concave ; umbilicus 
generally quite te filled. 
: small, broadly ovate; umbilicus a narrow slit, not penetrating ; callus with 
single transverse groove 
incertus : small, ovate ; umbilicus closed ; callus with single groove, above which it 
аыр on to apais tal w 
modestus: small, ovate; umbilicus closed ; callus broadly rounded off below, grooves 
inconspicuous 
moderate size, ovate; umbilicus generally closed or with a narrow chink ; 
callus narrow with two transverse almost parallel grooves 
scalptus : moderate to small, broadly ovate; transverse grooves low down; aperture 
greatly inclined. 
* See HED 
No. 3, 1924, an Lares which the author has been enabled to see since 
C., Some Naticoids from Сайыы. Rec. Aust. Mus., vol. 14, 
the reading of 
this paper. 
