Pvn H,i I'UitlS

PSAMMOBIA. 397
tured and forms the upper side of an obtuse angle : beaks
small, pointed, somewhat calyciform, almost contiguous, slightly
turned towards the posterior side : ligament rather short, pro-
minent, keeping the valves asunder in that part : hinge-line
obtusely angular : hinge-plate thick, broader on the posterior
side, abruptly truncate at the outer end of the ligament : teeth,
in the right valve two triangular, somewhat diverging, and
nearly equal-sized cardinals ;
in the left valve a central car-
dinal of the same size and a minute laminar one set obliquely
the three largest teeth
or at a right angle to the hinge-plate ;
are bifid : inside thickened, highly polished, and partially iri-
scar dis-
descent, usually stained with purple or lilac : pallial
tinctly marked, sinuated as in the two last : species muscular
scars
irregularly triangular. L. 1. B. 1*8.
Var. elongata.
Habitat :
Shell broader or more produced at each end.
Rather common on all the British coasts,
in sandy and nnllipore ground, at depths of from 4 to
90 fathoms. The variety is from Ullapool. Fossil at
Preston (J. Smith); Belfast (Grainger); Coralline Crag
(S. Wood). The exotic distribution of this species, both
north and south, is extensive, and embraces Iceland
(Leach), Faroe Isles (Chemnitz), Scandinavia (Loven
and others), north of France (De Gerville and Mace),
coasts of Spain and Portugal and the Canaries (M 'Andrew),
both sides of the Mediterranean (Scaechi, Wein-
kauff, and others), and iEgean (Forbes), the range of
between 3 and 40 fathoms in the former
depth being
case, and between 8 and 40 fathoms in the latter. Broe-
chi and Philippi have included it in their lists of tertiary
shells from Italy.
Couch mentions having taken a specimen from the
stomach of a Picked Dog-fish, one of a predaceous tribe
that might have been supposed to disdain such " small
deer." The shells are always to a certain extent twisted,
and sometimes so much so as to be distorted. The fry »
are triangularly oval.