Sur l'association de Murex trunculus L. avec éponge et bryozoaire.

Two species of Murex live in Tunis Gulf; Murex brandaris L, who lives in rocky bottoms between 6 to 8 m deep, and whose shells are clean and without deposits and Murex trunculus, who lives on the muddy bottom of the gulf between 4 and 5 meters deep, and whose shell is sometimes inlaid with red Clathria (red siliceous sponge), sometimes by a lightly tinted pink bryozoan: Schizoporella auriculata (Hassall) var. euspidata (Hinccks). Clathria seems set on youth live molluscs and manages to completely wrap the shell of the mollusk; while the bryozoan form variables sizes of plates on larger individuals of Murex, whether alive or inhabited by hermit crabs.