Pvn H,i I'UitlS

CYAMIUM. 263
old, and continued in a torpid or quiescent state even
after they had been provided with a fresh supply of
water. In this state, however, the shells were partly
open, and the Cyamia were still feeding. The fry are
enveloped in irregularly oval gelatinous masses, each
containing from 12 to 20 individuals. These spawnmasses
are deposited on extraneous substances; so
that the animal is not viviparous. The fry are found
in various stages of development ; but in every state the
shells are perfectly formed and can be seen through the
transparent envelope.
'
Fleming, in his British Animals/ seems to have mis-
taken this species for Lascea rubra. It is the My a purpurea
of Montagu. Brown placed it in the genus Saxi-
cava, Deshayes in Chione, and Moller in Lescea.
In some shell-sand dredged for Dr. Lukis at about
20 fathoms, on the east coast of Guernsey, and within
two miles of the land, I found not only a living CVzr-
dium papillosum and other rarities, but also a young and
perfect specimen of Cardita lithophagella
of Lamarck.
It is the Byssomya Guerinii of Payraudeau, and is not
very uncommon in the Mediterranean. In all probability
it belongs to the genus Cypricardia. Lamarck, in
describing this genus, says that it has three cardinal
teeth and one lateral, and that Cardita has only one
cardinal and one lateral tooth. But the present species
has two cardinal teeth, and one posterior lateral tooth,
in each valve, besides an anterior lateral in the left
valve. The pallial scar is deeply sinuous or indented at
the posterior side, and the muscular scars are of enormous
size. In these respects it would come nearer to
Venerirupis. The ' Journal de Conchyliologie '
for 1850
has an able article by M. Mittre on this species, in which,
however, he erroneously considered it to be the Cypri-