74 
MOLLUSCA. 
Littorina. 
16. T. Mancuniensis. — The Manchester Turbo, pi. 
XXXVII.* fig. 15, 16. 
Turbo Mancuniensis. Brown, Transactions of the Manches¬ 
ter Geological Society, I. p. 63, pi. 6, fig. 1, 2. 
Shell ovate; body large; spire short, consisting of three 
ventricose volutions, separated by a channelled suture; body 
provided with many prominent, spiral ribs; three on the body 
above, with five or six concentric ones beneath on the base, and 
two on each of the volutions of the spire; these are crossed 
by numerous longitudinal wrinkles; aperture large, orbicular; 
outer lip expanded, smooth; pdlar lip with an oblong umbilicus 
behind it. Length upwards of a quarter of an inch; body 
nearly the same in diameter. 
Found in the lied Magnesian Marl at Collyhurst, Manchester, 
by E. W. Binney, Esq., and is in the museum of the Manches¬ 
ter Geological Society. 
17. T. minutus.— The Minute Turbo, pi. XXXVII.* fig. 
17, 18. 
Turbo minutus . Brown, Trans. Manchester Geo. Soc. I. p. 
63, pi. 6, fig. 4, 5. 
Shell slightly ovate; body very large; spire very small, con¬ 
sisting of three abruptly diminishing volutions, flattened above, 
terminating in an obtuse apex, and separated by a somewhat 
grooved suture; aperture orbicular; outer lip slightly notched 
on the edge, produced by the projecting ribs; whole shell 
covered with strong, slightly undulous transverse costa?, two on 
the superior portion of the body, the lower one so much larger 
than the others, that it produces a carinated appearance, and 
with four or five concentric ribs below on the base, which is 
flattened; pillar lip with an umbilicus behind. 
Found in the lied Magnesian Marl at Collyhurst, Manchester, 
by E. W. Binney, Esq., and is in the Manchester Geological 
Society’s museum. 
Genus XXXII LITTORINA_ Fet 'ussac. 
Shell turbinated, generally ovate, or oblong-ovate, for 
the most part thick and solid; spire in general gradually 
acuminated and subturreted, in some species very short 
and obtuse at the apex; aperture round, or slightly ellip¬ 
tical, somewhat acute above in some species; outer lip, 
or peritreme, sharp-edged; columella somewhat flattened; 
operculum horny, spiral, consisting of a few rapidly en¬ 
larging volutions, and furnished with a central nucleus. 
1. L. Baiitonensis. —The Barton Littorina, pi. XXXVIII. 
fig. 54, 55. 
Turbo littoreus. Sowerby, Min. Conch. I. p. 163, pi. 71, 
fig. 1, two upper figures. 
Shell oblong-ovate, thick; body large; spire small, consisting 
of three moderately inflated, well defined volutions, with their 
upper parts nearly flat, terminating in an obtuse apex; whole 
surface covered with fine spiral, somewhat irregular stria?; aper¬ 
ture subovate, rounded beneath, and slightly contracted above; 
outer lip even at the edge, considerably thickened within; pillar 
lip broadly reflected on the columella. 
This shell differs from the L. communis in being much more erect, 
in the volutions being much flatter on the sides, and in its obtuse 
apex. 
Found in the Crag at Bramerton Ilill, near Norwich. It is 
often procured with the coloured bands quite distinct. 
2 . L. communis. —The Common Littorina, pi. XXXVIII. 
fig. 56. 
Turbo littoreus . Sowerby, Min. Conch. I. p. 163, pi. 71, 
lower figure 1. 
Shell subovate; body large; spire short, acute, consisting of 
three or four moderately inflated volutions, terminating in an 
acute apex; aperture suborbicular, slightly contracted above; 
whole surface covered with numerous, slightly nodulous, but 
regular stria?. 
Found in the Crag at Bramerton Hill, near Norwich. 
3. L. rudis.— The Robust Littorina, pi. XXXVIII. fig. 
57, 58. 
Turbo rudis . Sowerby, Min. Conch. I. p. 164, pi. 71, fig. 2. 
Shell subovate; body occupying more than two-thirds of the 
shell; spire consisting of four moderately inflated and well 
defined volutions, swelled above; whole shell covered by 
numerous spiral, somewhat irregular striae; these are crossed 
by a few inequidistant, longitudinal wrinkles, or lines of growth, 
which gives the shell a rugged aspect. 
Found in the Crag, near Aldborough. 
4. L. pungens. —The Pricking Littorina, pi. XXXVII.* 
fig. 19. 
Littorina pungens. Sowerby, Trans. Geo. Soc. IV. 2nd 
series, p. 343, pi. 18, fig. 5. 
Shell conical, smooth; body large, ventricose; spire short, 
consisting of five narrow, gradually tapering volutions, a little 
flattened at the sides, and terminating in an acute apex; aper¬ 
ture orbicular, with an acute, angular elongation above; outer 
lip thin, and even. 
Found in the Lower Green Sand, Blackdown, by Dr. Fitton. 
5. L. GRAciLis—The Slender Littorina, pi. XXXVII* 
fig. 20, 21. 
Littorina gracilis . Sowerby, Geo. Trans. IV. 2nd series, 
p. 343, pi. 18, fig. 12. 
Shell elongated, acute; body shorter than the spire, which 
consists of five ventricose, deeply divided, and gradually taper¬ 
ing volutions, terminating in a pointed apex; aperture round, 
with a slight angle below; outer lip even; pillar lip slightly 
reflected on the columella; whole surface covered with wide, 
longitudinal, regular furrows, which are crossed by transverse 
spiral strise, giving it a fine decussated aspect. 
Found in the Lower Green Sand at Blackdown, by Dr. 
Fitton. 
Genus XXXIII.— TROCHUS.—Linncsus. 
Shell conical; spire elevated, sometimes abbreviated; 
aperture more or less transversely depressed, frequently 
quadrangular or trapeziform, its edge being oblique to 
the direction of the last volution, exhibiting the inferior 
portion of the columella; base generally flattish, or, in 
some instances concave; columella more or less arcuated, 
