[Mollusks in the Bou Grara Sea (southern, Tunisia): initial biometric data on Cerastoderma glaucum Poirêt, 1789 (Bivalvia, Eulamellibranchia, Cardiae)].

The statistical study of Cerastoderma glaucum in the little harbour of Bou Grara points out the presence of 21 ribs on the valves, a mean growth of 19,3 mm for the first year of life and a mean longevity of two years; the formation of rest rings is made at summer period. The dynamical study of the population shows its large homeostasy.