p. 173 - 200 CONTRIBUTIONS A L'ETUDE QUANTITATIVE DU PHYTOPLANCTON MEDITERRANEEN DEVANT LES COTES LIBYENNES V.H. Skolka, N. Bodeanu, A.S. Bologa et Anca Roban Institute Roumain de Recherches Marines Constanta Abstract The paper presents the results on density, biomass and photosynthetic pigments in phytoplanktonic samples collected in the Libyan Mediterranean waters during four researches cruises conducted between 1975 and 1976. Planktonic primary productivity is evaluated in relation to hydrological conditions and nutrient concentration.