Pvn H,i I'UitlS

84 PECTINID-E.
valve now before me, one of the ears is twice the size of
the other. The fry, —th of an inch long, are roundish-
oval and distinctly ribbed.
L. subauriculata differs from L. elliptica in the shell
being more arched or equally convex throughout, as
well as much smaller and longer ; the sculpture is coarser
and the ribs fewer; the ears are smaller and droop a
little; and the furrow is straight and placed in the
middle. In the other species the shell is considerably
the sculpture is finer and
broader and more expanded ;
the ribs more numerous ; the ears are larger and more
erect; and the furrow runs obliquely, and is placed
somewhat nearer to the posterior margin. The young
of each species have corresponding characters. That
of L. elliptica resembles L. Sarsii in shape, but differs
toto ccelo in the sculpture and in having a conspicuous
furrow.
The present species is the L. sulcata (" Leach ") of
M oiler, L. elongata of Forbes, L. subauricula of Phi-
lippi, L. sulculus (" Leach ") of Loven, andL. unicostata
of Leach's posthumous work on the Mollusca of Great
Britain. I at one time thought it might also be the
Ostrea nivea of Renier, which has been well described
and figured by Brocchi. But although our shell is found
in the Adriatic, and may therefore have been the species
intended by Renier, I do not believe it occurs in the
Subapennine tertiaries, so as to have fallen under
Brocchi's observation ; and neither of these authors has
noticed the central groove or furrow, which is so charac-
teristic of this species and L. elliptica. The Ostrea
subauriculata of Turton's '
Conchological Dictionary '
appears to have been the young of L. Loscombii, judging
from his description and specimens.