p. 181 - 197 EXPERIMENTATIONS D'HIBERNATION DE QUELQUES ESPECES DE MUGILIDES EN CONDITIONS DE LABORATOIRE Valerian Udrea Institute Roumain de Recherches Marines Constanta Abstract The paper presents the experimental results on winter passing of 3 mullet species (Mugil cephalus, M. Auratus and M. Saliens) during 1972-1973 winter. The experiments pointyed out the temperature ranges to keep in order to ensure an optimum survival. In the some time the experiments allowed knowledge on the populations densities per cubic meter to have into considerations on designing the winter passing basins.