Pvn H,i I'UitlS

80 PECTINID^.
could scarcely be distinguished from Limopsis. The
species which he noticed were five in number, viz. two
from the lias and lower oolite, and three from tertiarystrata.
But in giving the Ostrea strigilata of Brocchi
as the type of his genus Limea, he seems to have mis-
understood the Italian geologist, who nowhere mentions
the hinge of his shell being toothed. The words used
by him are, " II margine delle valve comparisce crenellato
tutto all* intorno ; il cardine non e obbliquo come
nella precedente [Ostrea tuberculata, Olivi) ma sibbene
retto, e nel? area del legamento si scorge
una fossetta
trasversalmente bislunga." Brocchi^s species belongs
to the section which comprises our L. Loscombii. Loven
it to be
adopted Bronn's genus for L. Sarsiij considering
a passage towards Limopsis, and says that the mantle of
the animal has no cirri ;
but Sars, in his account of the
Arctic Mollusca on the coast of Upper Norway, has
since observed that the mantle of this species is like
that of the rest, and set with proportionally large ten-
tacles or cirri which are thick and ringed, although not
particularly numerous. According to Searles Wood,
some of his specimens of L. subauriculata from the Crag
have the hinge-plate minutely crenulated. The same
character is seen in many species of Pecten. These
crenulations probably serve for the firmer attachment
of the cartilage to the hinge-plate, and not for a separate
fastening as in the interlocking teeth of Area. They
Norwe-
are too slight for the last-mentioned purpose.
gian specimens of L. Sarsii are much larger than ours.
This and the next two species form a distinct section,
which Klein more than a century ago called Ctenoides,
and for which Searles Wood has proposed the subgenus
Limatula.