Natica. 
MOLLUSCA. 
89 
effuse; outer lip sharp-edged, smooth within; columellar 
lip transversely oblique, destitute of teeth, generally 
thickened, and sometimes with a coating of enamel 
spread thickly over the umbilicus; umbilicus usually 
large, having a spiral callosity within, which in some 
instances increases so as to cover it, in others it is very 
small, and in a few instances nearly obsolete, so much 
so, as to be hardly perceptible as an umbilical opening; 
operculum testaceous in some species, and horny in 
others. 
1 . Natica glaucinoides. — The Grayish Natica, pi. 
XLIII. fig. 30, 31. 
Natica glaucinoides. Sowerby, Min. Conch. I. p. 19, pi. 5, 
three upper figures. Fleming, Brit. An. p. 320. 
Shell semiglobular; body very large, inflated, slightly flat¬ 
tened, and a little concave above; spire small, consisting of 
four rounded, rapidly decreasing volutions, terminating in a 
pointed apex; umbilicus large, simple, while in some specimens 
it is partly closed, by a slight elongation of the glazing of the 
pillar lip; surface very glossy, of a light grayish-brown colour, 
with indications of darker bands. 
This shell strongly resembles N. glaucina , but its spire is more pro¬ 
duced than in that species, the inner lip is also stronger, and liable to 
become callous over the umbilical region. 
Found in the London Clay at llighgate, and in the Suffolk 
Crag. 
2. Natica similis. —The Similar Natica, pi. XLIII. fig. 
28, 29. 
Natica similis. Sowerby, I. p. 20, pi. 5, two middle figures. 
Fleming, p. 320. 
Shell smooth, somewhat rhomboidal, or slightly ovate; spire 
very short, consisting of three or four depressed volutions, the 
apicial one obtuse; aperture sublimate, longitudinal; outer lip 
not much expanded, and plain; inner lip thickened, bilobate, 
dividing the umbilicus, which is deep, and with a flattened area 
at its lower side. 
Found in the London Clay at llighgate, and also at Bognor. 
3. Natica discrepans —The Differing Natica, pi. XLIII. 
fig. 24. 
Natica glaucinoides. Sowerby, V. p. 126, pi. 499, fig. 4. 
Shell ovate, smooth, and glossy; spire very short, consisting 
of four depressed volutions, with the apicial one obtuse; aper¬ 
ture large, sublunate, with the outer lip considerably expanded, 
and plain at the edge; pillar lip broadly thickened upon the 
columella above, but narrowed below; umbilicus deep and wide, 
but suddenly contracting internally. 
This shell differs from the N. glaucinoides , in its more expanded 
outer lip, and in the aperture being larger in proportion to the size of 
the shell. 
Found in the Suffolk Crag, and at Bramerton, Norfolk. 
4. Natica sigaratina. —The Sigaritus-formcd Natica, pi. 
XLIII. fig. 18, 19. 
Natica sigaratina. Sowerby, V. p. 126, pi. 479, fig. 3. 
Fleming, p. 321. 
Shell smooth, greatly depressed; spire small, with three ill 
defined volutions, hardly rising above the body; aperture ovate, 
obliquely curved, and contracted above; outer lip even; thick¬ 
ening on the pillar narrow; umbilicus large, nearly filled with a 
lenticular callus, a small portion, however, is always open. 
Found in the London Clay. 
5. Natica cirriformis. —The Cirrus-shaped Natica, pi. 
XLIII. fig. 20, 21. 
Shell subglobose ; spire rather short, consisting of three well 
rounded, but somewhat depressed volutions, the apicial one 
much blunted; body rather flattened above; aperture small, 
sublunate, rounded both above and below; pillar lip thickened, 
with a central sinus; umbilicus very large, intruding upon the 
columella, destitute of a spiral ridge, and exposing the volutions 
internally as far as the apicial one ; behind the pillar lip some 
strong, elevated, nearly equidistant, longitudinal ridges. 
Found in the Suffolk Crag. 
6. Natica patula —The Open Natica, pi. XLIII. fig. 
22, 23. 
Natica patula. Sowerby, IV. p. 99, pi. 373, three lower 
figures. Fleming, p. 321. 
Shell slightly ovate; body very large, flattened in front; spire 
very short, and much depressed, hardly rising above the general 
surface of the body, consisting of four very small volutions, ter¬ 
minating in an acute apex; aperture sublunate, rounded both 
above and below; pillar lip considerably thickened; umbilicus 
large, and partly filled by a callus, with a smaller one, forming 
a spiral ridge within; general surface smooth, with very minute, 
concentric stria;, and rather obsolete lines of growth. 
Found at Ipswich, in the Suffolk Crag. 
7. Natica cincta. — The Girdled Natica, pi. XLIII. 
fig. 25. 
Natica cincta. Phillips, I. p. 101, pi. 4, fig. 9. 
Shell ovate; spire depressed, consisting of three volutions, 
flattened above; body with a large obliquely flattened space 
above, with a subcarinated edge; aperture sublunate, with a 
sharp outer lip, and a moderately thick columellar glazing; um¬ 
bilicus rather small; outer surface smooth, with distinct lines of 
growth; the body invested by a spiral fillet or band. 
Found in the Coralline Oolite at Malton. 
8. Natica ampliata. —The Ample Natica, pi. XLIII. fig. 
26, 27. 
Natica ampliata. Phillips, II. p. 224, pi. 14, fig. 21 and 24. 
Shell hemispherical; body very large, much inflated; spire 
very small, sunk behind the outer lip, and consisting of two 
much depressed, ill defined volutions; aperture ample; outer 
lip much expanded; columellar lip plane; whole surface covered 
with small, equidistant, filiform, longitudinal stria\ 
Found in the Mountain Limestone at Bolland, and in Nor¬ 
thumberland. 
9. Natica plicistria —The Plicistriate Natica, pi. XLIII. 
fig. 32. 
Natica j)licistria. Phillips, II. p. 225, pi. 14, fig. 25. 
Shell oblong-ovate; body large, smooth; spire small, sub¬ 
conic, consisting of three plicistriate volutions, their superior 
edges being obliquely flattened, as well as that of the body. 
When the shell is old, the flat space becomes concave. 
Found in the Mountain Limestone of Bolland, Bristol, Nor¬ 
thumberland, Kirby Lonsdale, and Kildare, Ireland. 
10. Natica adducta. —The Close Natica, pi. XLIII. fig. 
33 and 41. 
Natica adducta. Phillips, I. p. 123, pi. 9, fig. 30, and p. 
129, pi. 11, fig. 35. 
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