84 
MOLLUSCA. 
Vermetus. 
Genus XXXIX _VERMETUS— Adanson. 
Shell thin, tubulosc, loosely spiral in the lower portion, 
three or four upper volutions regularly spiral; adherent 
to extraneous substances by the apex of the spiral part; 
aperture orbicular; margins united, and provided with 
an operculum. 
1. V. Bognoriensis,— The Bognor Vermetus, pi. XLIII. 
fig. 1. 
Vermetus Bognoriensis. Sowerby, Min. Conch. VI. p. 194, 
pi. 59b, fig. 1, 2, 3. Vermicularia Bognoriensis , Mantell, Geo. 
of Sussex, p. 272. Serpida ? Parkinson, Org. Rem. III. p. 
97, ph 7, fig. 8. 
The spiral portion smooth, circular, conical, and concave 
beneath ; tube obscurely pentangular, with a furrow above and 
below ; the tubular projection cylindrical, slightly curved, and 
generally exceeding in length the longest diameter of the shell. 
This species is gregarious, and is plentiful in the Sandstone 
of the Bognor Rocks, and on the coast of Sheppy, as well as at 
Hialisrate Hill. Dr. Mantell mentions a block of Sandstone in 
his possession, about four inches square, which contains nearly 
twenty specimens lying in relief. 
2. V. polygonalis. —The Polygonal Vermetus, pi. XLIII. 
fig. 2. 
Vermetus poli/gonalis. Sowerby, Min. Conch. VI. p. 19b, 
pi. 59b, fig. b. 
Spiral portion in the form of a short cone, provided with one 
involute, prominent, erect ridge, which wind to the apex, and 
two 'less elevated ridges round the margin, where they ter¬ 
minate more prominently, and their points ending in two short 
spines; tubular projection, having a trumpet-shaped termina¬ 
tion, and with seven acute angles. 
Found at Seabrook, in Limestone belonging to the Lower 
Greensand series. 
3. V. concinnus _The Trim Vermetus, pi. XLIII. fig. 3. 
Vennefus concinnus. Sowerby, Min. Conch. VI. p. 195, pi. 
59b, fig. 5. 
Shell circularly convolute, slightly convex on one side, and 
concave on the other, a great portion of the tube projecting; 
tube pentangular, four of the angles acute, and the other rather 
obscure. 
Found plentifully in a brown Sandy Limestone in Robin 
Hood’s Bay, Isle of Wight. 
4. V. tumidus _The Tumid Vermetus, pi. XLIII. fig. 
4,5. 
Vermetus tumidus. Sowerby, Min. Conch. VI. p. 195, pi. 
59b, fig. 4. 
Shell thick, discoidal; with few volutions, seldom exceeding 
two; tube thick, externally marked with a broad, concentric 
furrow or two on the sides; prolonged portion small, short, and 
cylindrical; margin of the aperture thickened; apex with a 
callus. 
Found in the Coral Rag at Scarborough. 
5. V. concavus —The Concave Vermetus, pi. XXXVII.* 
fig. 40. 
Vermetus concavus. J. de C. Sowerby, Geo. Trans. IV. 
2nd series, p. 313, pi. 18, fig. 10. Fitton, lb., p. 228. Ver- 
micularia concava , Sowerby, Min. Conch. I. p. 125, pi. 57, figs. 
1 to 5. 
Shell smooth ; spiral portion depressed above, and concave 
beneath; three or four volutions, united at the sides by a spiral 
projection; prolonged portion always at least double the dia¬ 
meter of the spiral part in length ; tube rounded throughout. 
Found in the Greensand at Dilton, near Wcstbury, and in 
the Upper Greensand of Dorsetshire. 
G. V. striatus.— The Striated Vermetus, pi. XLIII. fig. 
14, 15. 
Planorbis radiatus. Sowerby, Min. Conch. II. p. 92, pi. 
140, fig. 5. Fleming, Brit. An. p. 279- 
Shell strong; with the spiral portion of the volutions nearly 
lenticular, considerably produced, and nearly concealed in the 
lower side; both sides traversed by radiating stria?, which are 
sharp and acute in and near the umbilicus, but gradually 
become obsolete towards the back of the volutions; under side 
umbilicated; aperture orbicular, swelling at the margins; thick¬ 
ness about a fourth of its diameter. 
Found in the Greensands of Blackdown, Devonshire. 
FAMILY III.—PLICACEA. 
Shell with the aperture somewhat contracted, and the 
columella plaited. 
Genus XL.—TORN AT ELL A.— Lcnnarch. 
Shell oval or oblong, cylindrical, generally grooved or 
striated; spire very short, and somewhat obtuse, in a few 
species acute; aperture longitudinal, elongated, not less 
than half the length of the shell, but frequently two- 
thirds, straitened above, and somewhat widened below ; 
outer lip simple, with an acute edge; inner lip thin, and 
but slightly reflected over the body; columella, which is 
spiral, thickened, plaited, its base confluent with the 
outer lip. 
1. T. acutus —The Acute Tornatella, pi. XLIII. fig. G, 
7, 8. 
Tornatella acutus. Fleming, Brit. An. p. 33G. Acteon 
acutus , Sowerby, Min. Conch. V. p. 78, pi. 455, fig. 2. 
Shell subcylindrical, smooth; spire short, conical, and acute; 
columella provided with one plait; aperture about three-fourths 
the length of the shell. 
Found in the Oolite at Anclide. 
Fig. 7, natural size; G and 8, magnified. 
2. T. Noje. —Noah’s Tornatella, pi. XLIII. fig. 9, 10. 
Tornatella Nocc. Fleming, Brit. An. p. 33G. Acteon Noce, 
Sowerby, Min. Conch. IV. p. 101, pi. 374. 
Shell oval, fragile, subcylindrical; with one large plait at the 
base of the columella; aperture ohlong-ovate, straitened, and 
pointed above, much widened and rounded below; outer lip 
sulcated within; whole surface covered with numerous, equi¬ 
distant, transverse stria?, and obscurely decussated by longitudi¬ 
nal stria?. 
Found in the Crag at Walton, Essex. 
