46
CORBULID.E.
cular cardinal : in the left valve a small, sunken and triangular
cardinal, besides a long but slight laminar lateral on the posterior side : inside glossy and nacreous, closely but obscurely
lineated lengthwise; edges sharp: jnuscidar scars triangular,
lying near the dorsal margins. L. 0-325. B. 0-375.
Habitat : In mud among boulders^ 40-45 f., close
to Croulin Island^ and in another part of the Sonnd of
Skye; rare. Mr. Dawson found a worn and imperfect
valve in sliell-sand from Haroldswick Bay in the north
of Shetland. Coralline Crag (S. AYood) ; newer tertiary
beds near Antwerp (Nyst and Westendorp) . Koren
got it at Bergen ; M^Andrew and Sars dredged it off the
coasts of Finmark, the former in 45-90 f. ; Deshayes
obtained it from Sicily and Bona, and Tiberi at Naples
Forbes in the ^Egean between 40 and 150 f
. ;
and
:\IMndrew at Madeira in 20 f.
Clark conjectm'ed that this might be the young of
Thracia convexa, and he said that the present species
has an ossicle in the hinge ; but he did not see with my
eyes.
I have compared specimens of P. gramdata and
T. convexa of all sizes, fi'om the fifteenth of an inch in
length.
Each exhibits a marked difference of outline :
one is square, and the other triangular. I have also
examined perfect examples of the Poromya from Scandinavia, Skye, and Naples ; and in none of them could
I detect an ossicle or any space for it. He also stated
that the siphons of these two mollusca are equally short,
and ornamented with cirri or filaments ; but neither of
these characters was noticed by him in his elaborate
account of the only species of TJiracia described in the
' History of the British Marine Testaceous Mollusca,"
and he admitted that he had not seen the animal of T.
convexa or of P. granulata.
Forbes described the recent shell as P. anatinoides
CORBULID.E.
cular cardinal : in the left valve a small, sunken and triangular
cardinal, besides a long but slight laminar lateral on the posterior side : inside glossy and nacreous, closely but obscurely
lineated lengthwise; edges sharp: jnuscidar scars triangular,
lying near the dorsal margins. L. 0-325. B. 0-375.
Habitat : In mud among boulders^ 40-45 f., close
to Croulin Island^ and in another part of the Sonnd of
Skye; rare. Mr. Dawson found a worn and imperfect
valve in sliell-sand from Haroldswick Bay in the north
of Shetland. Coralline Crag (S. AYood) ; newer tertiary
beds near Antwerp (Nyst and Westendorp) . Koren
got it at Bergen ; M^Andrew and Sars dredged it off the
coasts of Finmark, the former in 45-90 f. ; Deshayes
obtained it from Sicily and Bona, and Tiberi at Naples
Forbes in the ^Egean between 40 and 150 f
. ;
and
:\IMndrew at Madeira in 20 f.
Clark conjectm'ed that this might be the young of
Thracia convexa, and he said that the present species
has an ossicle in the hinge ; but he did not see with my
eyes.
I have compared specimens of P. gramdata and
T. convexa of all sizes, fi'om the fifteenth of an inch in
length.
Each exhibits a marked difference of outline :
one is square, and the other triangular. I have also
examined perfect examples of the Poromya from Scandinavia, Skye, and Naples ; and in none of them could
I detect an ossicle or any space for it. He also stated
that the siphons of these two mollusca are equally short,
and ornamented with cirri or filaments ; but neither of
these characters was noticed by him in his elaborate
account of the only species of TJiracia described in the
' History of the British Marine Testaceous Mollusca,"
and he admitted that he had not seen the animal of T.
convexa or of P. granulata.
Forbes described the recent shell as P. anatinoides