Pvn H,i I'UitlS

74 PECTINID.E.
rarely, the colour is white, with an orange tint at the beaks :
margins semicircular in front and sloping
at the distance of
about one-fourth from the hinge-line at an angle of 30 degrees
to the beaks ; byssal slope not notched or serrate : beaks small
and not prominent in full-grown specimens : ears exactly equal
on the upper valve and nearly so on the other valve, furnished
with a few ribs or striae which radiate from the beaks ; byssal
notch closed in the adult state: hinge-line straight, rather
more than half the breadth of the shell : cartilage large, thick,
and strong: ligament narrow and rather slight: hinge-plate
broad, closely and microscopically striate across ; transverse
rib strong and raised on each side of the broad cartilage-pit ;
in the lower or deeper valve are two or three short oblique
ribs, which diverge from above the cartilage-pit towards the
sides in wave-like lines : inside glossy, tinged more or less
deeply with reddish-brown, fluted as in P. opercularis, and
having similar shoulders or ledges on the posterior slopes to prevent
contact at the hinge -area : muscular scars well marked,
especially on the upper
Habitat :
on banks,
Nearly
valve. L. 4*5. B. 5.
everywhere, and often gregarious
in 7-78 fathoms. It is also not uncommon
in all our upper tertiaries, both new and old. Its foreign
range comprises all the sea-bed lying between Norway
and the Canaries ; and, according to Sars, it occurs with
arctic shells in the "postglacial " beds of Christiania.
If the oyster is the king of mollusks, this has a just
claim to the rank and title of prince. In Lister's time
they were held in nearly the same esteem; and the
great scallop is even preferred by some, although from
its luscious quality it is not so provocative of appetite.
I have not heard of its being eaten raw in this country.
In the fish-markets of the north of France it is called
" grand'-pelerine," l '
gofiche," or " palourde." In the
south of England it shares with P. opercularis the name
of " frill/' and in the north that of " clam." According
to Afhenreus, this or an allied species (P. Jacobceus) was
used by the ancients for medicinal purposes, as well as