Pvn H,i I'UitlS

56 PECTINID^.
have the fry attached to a rib of Rissoa parva, showing
that they remove from place to place, at least in the
earlier stages of growth. The hooded crow is very fond
of these scallops.
It takes one from the tangle at low
water and carries it to the shore or a bank, on which it
drops its prey, watching with cunning patience
scallop opens its shell. It then quickly
until the
thrusts its
pointed and strong beak into the gaping valves, forces
them asunder, and devours the dainty morsel. Dead
and bleached shells are thus often found in places at
some distance from the sea, where crows had been feast-
ing. Without this explanation they might have been
mistaken for fossils. Specimens of the variety pur-
purea attain a considerable size. One of mine is 3^%
inches long and 3 inches broad. This species differs
from the younger state of P.pusio in being larger, and
in the ribs being much less numerous, and equal in size
instead of alternately large and small. Being
free and
Of a regular shape at all ages, it is readily distinguishable
from the adherent and distorted adult of the other
species.
I fear that some of my conchological
terribly shocked at my innovation in uniting
friends will be
P. niveus
with P. varius ; but I feel constrained to take this bold
step, even at the risk of not being soon forgiven. I had
for a long time great misgivings on the subject; but it
was not until I had most carefully examined and com-
pared a multitude of specimens
of both these so-called
species, collected from various and distant places, that I
was able to arrive at a satisfactory conclusion. The
only points
of difference between P. varius and P. niveus
consist in the latter having a broader and flatter shell
with more numerous and delicate ribs, and in the colour
being
white. All these characters are combined or