The singularity of form that gave rise to its common name renders it
easily distinguished. It very much resembles a wedge, being very broad
and thick at one extremity, and gradually tapering towards the other.
They vary in colour, but the most general is purple radiated on a white
ground, diverging from the beak to the margin; many have an orange
tinge, and others a pink hue; the interior generally partakes of the
colour of the exterior. There are not, perhaps, two species that have
absolutely the same hinge.
The Donax is found buried deep in the sand of the seashore, with the
short side uppermost.
Shell sub-trigonal, greater in length than in height, equivalve, very
inequilateral; posterior side much shorter than the anterior; summits
almost vertical; hinge complex, similar; two cardinal teeth in one or
both valves; one or two remote lateral teeth on each valve; ligament
posterior, short, and inflated; two rounded muscular impressions.
Donax scortum.
D. pubescens.
D. compressa.
D. cuneata.
D. deltoides.
D. radians.
D. abbreviata.
D. triquetra.
D. ringens.
D. rugosa.
D. Cayennensis.
D. elongata.
D. denticulata.
D. granosa.
D. columbella.
D. veneriformis.
D. Australis.
D. epidermia.
D. bicolor.
D. vittata.
D. meroe.
D. scripta.
D. trunculus.
D. flabagella.
D. cinatinum.
D. Martinicensis.
D. cardioides.
_D. scortum._ The beaked Donax. Pl. 8, fig. 4.
Species oval, of which the posterior side is sub-truncated; with
decussated and muricated striæ.
_D. trunculus._ The common Donax.
Oblong, glossy, finely striated longitudinally, transversely banded and
radiated with purple; white, clouded with purple within; internal margin
of the valves distinctly dentated or crenulated.
_D. denticulata._ The denticulated Donax.
Species of which the posterior side is truncated; furrowed from the
summit to the base.