Pvn H,i I'UitlS

278 CARmiDM.
5. C. exi'guum*, Grmelin.
C. exiguum, Linn. Syst. Nat. (ed. Gmel.) p. 3255. C. pt/gmaicm, F. & H.
ii. p. 29, pi. xxxii. f. 8, and (animal) pi. 2s . f. 2.
Body triangular and much truncated at the posterior side,
jello wish-white : mantle plain-edged in front, and fringed
with numerous white filaments about the bases of the siphonal
tubes : incurrent (or branchial) tube the larger of the two, and
8urrounded by a border of about ten filaments, with as many
there is also a tinge
or more tawny streaks radiating from it ;
of tawny or orange around the orifice of the smaller or excurrent
tube both are ; nearly sessile : foot long, cylindrical, and
large in proportion to the body ; its base is tinged with tawny,
the rest being white.
Shell obliquely triangular, exceedingly gibbous, solid and
opaque, usually of a dull hue, and never so glossy as that of
the last species : sculpture, 20 or 21 ribs, "which are at firstsharp
and angular but afterwards become compressed and
broad, especially in front ; the ribs are in young specimens
more or less covered with small white tubercles, which are
not formed in the adult except on the anterior side ; the fur-
rows, which are very narrow, are crossed and indented by
numerous regular, oval : punctures colour yellowish or dirtywhite,
sometimes variegated by purplish-brown streaks or
blotches, which are more visible on the posterior side, occa-
sionally tinged with pink : epidermis fibrous and often thick,
yellowish-brown of different shades : margins bluntly angular
on all sides except in front, where there is a contraction simi-
lar to that in C. tuberculatum, causing this side to be very
gently curved, and not so much rounded as in most other
species ; the angle or ridge separating the posterior side is
very conspicuous and increases the gibbosity
of the shell:
beaks very small, not contiguous, inclining a little to the ante-
rior side, and placed very much nearer to it ;
beneath them on
this side is a deep and heart-shaped or lanceolate ribless de-
pression, more like a lunule than the similar mark in any of
the preceding species, and having slightly projecting lips :
ligament short and sunken, cylindrical, :
yellowish-brown
curved :
hinge-line slightly
hinge-plate thick, reflected, occupy-
in the
ing scarcely one-fourth of the circumference : teeth,
right valve two cardinals, the posterior of which is much the
* Little.