Pvn H,i I'UitlS

392 TELLINID.E.
1. Psammobia tellinel'la *, Lamarck.
P. tettinella, Lam. An. sans Vert. v. p. 515 ; F. & H. i. p. 277, pi. xix. f. 4,
and (animal) pi. K. f. 1.
Body oblong, pure white : mantle dentated in front and
fringed
behind from the beaks to the tubes: the latter are
moderately long, tapering, and divergent ;
the excurrent tube
is the more slender, and curved upwards, marked lengthwise
with eight fine lines of intense frosted white running from one
end to the other, and having its orifice encircled with exceed-
orifice of incurrent tube
ingly
minute and short white cirri ;
furnished with six similar cirri and intermediate shorter ones :
gUls suboval, pale brown, hanging obliquely, and coarsely
striated on both sides; upper very small: palps rather subtriangular, pointed,
long,
pale brown, outwardly smooth, and
inwardly coarsely pectinated transversely, not furrowed as in
Tellina donacina : foot flat, sharp-edged, slightly bent, and
lanceolate at the point.
Shell oblong, compressed, rather thin than solid, opaque,
slightly glossy: sculpture, very delicate and close-set but
somewhat irregular concentric striae, with occasional and more
strongly-marked lines of growth ;
the concentric or transverse
striae are crossed by others, which are longitudinal and equally
fine, but sometimes become larger and almost rib-like on the
posterior slope ; in fresh specimens the surface is thus faintly
decussated, but the longitudinal striae always predominate :
colour yellowish-white tinged with violet or flamecolour, varie-
gated by rays of either of those hues, or of pink, and diversified
by short longitudinal streaks or wavy and irregular lines
of the same tint ; usually on the anterior (and frequently also
on the posterior) side of the beaks are short but broadish rosy
the colour is uniform
streaks as in Tellina donacina ; rarely
milk-white or : purple epidermis thin, pale yellowish-brown,
generally obliterated : marc/ins slightly and obtusely
curved in
front, more acutely so on the anterior side, and bluntly pointed
at the posterior extremity, from which the margin in each
valve slopes with different degrees of curvature to the beak,
the deflection on each side of the umbo being nearly equal;
the posterior side is somewhat angular, and both sides are
wedge-like: beaks small, sharp, contiguous, turned towards
the posterior side : ligament short, prominent, at first of a
* Eesembling a small kind of Tellina.