Pvn H,i I'UitlS

PECTEN.
The 'Rev. Dr. Landsborough has given the following
interesting account of their habits in an earlier stage of
growth :—" We observed on a sunny September day in
a pool of sea-water left on Stevenston strand (Ayrshire)
by the ebbing tide, what we at first thought some of the
scaly brood at play. On close investigation, however,
we found that it was the fry of Pecten opercularis
skipping quite nimbly through the pool. Their motion
was rapid and zigzag, very like that of ducks in a sunny
blink rejoicing in the prospect of rain. They seemed,
by the sudden opening and closing of their valves, to
have the power of darting like an arrow through the
water. One jerk carried them some yards, and then
by another sudden jerk they
different tack. We doubt not that, when full-grown,
they engage in similar amusements, though, as Pectens
of greater gravity, they choose to romp unseen and play
their gambols in the deep." The animal of the adult
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were off in a moment on a
scallop, when at rest, is a study for a painter, with its
large and bright pink ovary, and its mantle studded on
each side with a row of brilliant eyelets, like dewdrops
glittering in the sun of a May morning. The trans-
verse plates form hollow or vaulted scales in young
shells ;
and their surface is minutely and closely tuber-
cled, like the cells of Polyzoa. In the fry the upper
valve is much larger than the lower one and overlaps
it. The ribs are not then formed, but the byssal sinus
is well developed. Specimens from the Firth of Forth
and Shetland are much larger than usual, although
slightly differing from each other in their relative pro-
portions. I have one from the latter district measuring
Sjjj inches long and 3^ broad, and another from Portobello
3^- long and nearly 4 broad. Occasional distor-
tions or monstrosities occur.