24
PANDORIDiE.
Searles Wood) no well determined fossil species have
been met with in any formation older than the Paris
basin.
The animal was inclnded by Poli in his genus
HypogcBa.
For the shell Bolton proposed Calopodium,
and Brown Trutina.
Pandora in^quival'vis^_, Linne.
TeUina inaquivahns, Linn. S. N. p. 1118. P. rostrata, F. & H. i. p. 207,
pi. viii. f. 1-4, and (animal, as P. ohtusa) pi. G. f. 10.
Body transparent, with flake-white specks ; manth thin,
scarcely (if at all) protruded : tubes short, separate although
nearly close together, issuing from a very slight, pellucid and
membranous sheath, which extends beyond the shell at its
posterior end, and is partly continued round the edges ; orifices
wide, plain but jagged : gills unequal-sized, the upper being
twice the size of the lower pair, which are almost rudimentary
they are pectinated by the blood-vessels on both surfaces
palps very short, redchsh-brown, striated transversely, and
often overlapping each other : foot white : liver green : ovary
red-brown.
Shell irregularly triangular, right or convex valve considerably overlapping the other; it is variable in thickness and opacity, and somewhat glossy: sculpture, slight plait-like marks of
growth, and sometimes a few imperfect longitudinal wrinkles on
the flat valve, which are only perceptible in front and appear to
radiate from the beak : colour pearl-white ; epidermis filmy
margins rounded or obtusely angular on the anterior side,
foiTQing in front a nearly semicircular but oblique curve,
which is prolonged at the posterior side to a blunt point
dorsal margin straight or slightly incurved, furnished in the
right valve with a double furrow, and in the left with a double
ridge, both of which extend from the beak to the posterior end
or point : heals extremely minute and tubercular ; umbones
not prominent : cartilage horn colour, running inwards on the
posterior side at an acute angle with the dorsal margin, and
occupying a groove in each valve, the sides of which are thickened : hinge-line straight, or more or less incurved : liingeplate long, strengthened by a rib in the left valve, that fits into
a sHght furrow in the opposite valve : teeth, in the right valve
* Valves unequal in size.
PANDORIDiE.
Searles Wood) no well determined fossil species have
been met with in any formation older than the Paris
basin.
The animal was inclnded by Poli in his genus
HypogcBa.
For the shell Bolton proposed Calopodium,
and Brown Trutina.
Pandora in^quival'vis^_, Linne.
TeUina inaquivahns, Linn. S. N. p. 1118. P. rostrata, F. & H. i. p. 207,
pi. viii. f. 1-4, and (animal, as P. ohtusa) pi. G. f. 10.
Body transparent, with flake-white specks ; manth thin,
scarcely (if at all) protruded : tubes short, separate although
nearly close together, issuing from a very slight, pellucid and
membranous sheath, which extends beyond the shell at its
posterior end, and is partly continued round the edges ; orifices
wide, plain but jagged : gills unequal-sized, the upper being
twice the size of the lower pair, which are almost rudimentary
they are pectinated by the blood-vessels on both surfaces
palps very short, redchsh-brown, striated transversely, and
often overlapping each other : foot white : liver green : ovary
red-brown.
Shell irregularly triangular, right or convex valve considerably overlapping the other; it is variable in thickness and opacity, and somewhat glossy: sculpture, slight plait-like marks of
growth, and sometimes a few imperfect longitudinal wrinkles on
the flat valve, which are only perceptible in front and appear to
radiate from the beak : colour pearl-white ; epidermis filmy
margins rounded or obtusely angular on the anterior side,
foiTQing in front a nearly semicircular but oblique curve,
which is prolonged at the posterior side to a blunt point
dorsal margin straight or slightly incurved, furnished in the
right valve with a double furrow, and in the left with a double
ridge, both of which extend from the beak to the posterior end
or point : heals extremely minute and tubercular ; umbones
not prominent : cartilage horn colour, running inwards on the
posterior side at an acute angle with the dorsal margin, and
occupying a groove in each valve, the sides of which are thickened : hinge-line straight, or more or less incurved : liingeplate long, strengthened by a rib in the left valve, that fits into
a sHght furrow in the opposite valve : teeth, in the right valve
* Valves unequal in size.