In the hinge and lateral teeth it much resembles the Tellina, but
differs from it in never being flexuous. This genus is more easily
characterized by the orbicular, compressed, general form of the shell,
than by the dental system, which is sometimes entirely effaced.
Shell compressed, regular, orbicular, sub-equilateral; summits small and
pointed, inclined anteriorly; hinge similar, but variable; two divergent
cardinal teeth, little marked, and sometimes entirely effaced; two
remote lateral teeth, with a pit at the base, sometimes obsolete;
posterior ligament more or less sunk; two widely-separated muscular
impressions, of which the anterior is narrow and long.
Lucina Jamaicensis.
L. Pennsylvanica.
L. edentula.
L. mutabilis.
L. radula.
L. squamosa.
L. lactea.
L. undata.
L. circinaria.
L. columbella.
L. concentrica.
L. divaricata.
L. carnaria.
L. scabra.
L. reticulata.
L. sinuata.
L. pecten.
L. lutea.
L. digitalis.
L. globularis.
_L. Jamaicensis._ The Jamaica Lucina. Pl. 8, fig. 8.
Species lenticular, striated concentrically; the teeth of the hinge
variable, and sometimes obsolete.
_L. undata._ The waved Lucina.
Orbicular, thin, convex, undulated with fine irregular striæ; exterior
pale yellow, interior white; margin glossy and plain.