Shell. Equivalve, transverse, without any irregular fold on the anterior margin, having the beaks flexed inward and opposite; two cardinal teeth; two lateral, the posterior of which is nearest the hinge; muscular impressions simple, ligament external. Inhabits the Indian Ocean.
- Corbis fimbriata.
- C. maculata.
7. Genus Lucina. Pl. [VII].
Animal. Very imperfectly known.
Shell. Inequilateral, suborbicular, beaks small, pointed, and oblique; two divergent cardinal teeth, one of which is bifid, and which vary or disappear with age; two lateral teeth sometimes obsolete, the posterior approaches nearest to the cardinal teeth; two muscular impressions far apart, the posterior in shape of a band, sometimes very long; ligament external. Inhabits the British and American seas. Twenty-six species.
- Lucina Jamaicensis.
- L. edentula.
- L. radula.
- L. lactea.
- L. circinaria.
- L. columbella.
- L. mutabilis.
- L. squamosa.
- L. Peruviana.
- L. fimbriata.
- L. undata.
- L. divaricata.
- L. scabra.
- L. sinuata.
- L. lutea.
- L. globularis.
- L. digitalis.
- L. Pecten.
- L. reticulata.
- L. carmaria.
- L. concentrica.
- · · · · ·
- L. bella.*
- L. Pennsylvania.*
- L. sphæroides.*
- L. Californica.*
- L. Nuttallii.*
8. Genus Donax. Pl. [VII].
Animal. As in Tellina.
Shell. Transverse, inequilateral, equivalve; anterior side short and obtuse; two primary teeth in one or both valves; one or two lateral teeth varying in distance; two round muscular impressions; ligament, external, short, and inserted at the posterior impression. Inhabits the seas of Europe and America. Thirty-one species.
- Donax pubescens.
- D. cuneata.
- D. radians.
- D. abbreviata.
- D. ringens.
- D. Cayennensis.
- D. denticulata.
- D. cinatina.
- D. cardioides.
- D. scorta.
- D. compressa.
- D. columbella.
- D. Australis.
- D. bicolor.
- D. merois.
- D. scripta.
- D. trunculata.
- D. fiabagella.
- D. Martiniænsis.
- D. triquetra.
- D. rugosa.
- D. elongata.
- D. deltoides.
- D. veneriformis.
- D. Vittata.
- D. granosa.
- D. epidermia.
- D. minima.
- · · · · ·
- D. variabilis.*
- D. fossar.*
- D. Californica.*