p. 75 - 81 ON THE RESPIRATORY RATE OF SOME MACROPHYTIC ALGAL SPECIES NEAR THE ROMANIAN BLACK SEA SHORE Alexandru S. Bologa Romanian Marine Research Institute Constantza Abstract The present paper is dealing with the determination of the respira- tory rate of 10 macrophytic algal species from the Romanian sea shore and the establishment of the correlation between morphological conformation and the value of respiratory rate. The values of respiratory rate confirm interspecifical differences depending on systematic affiliation as well as on interdependence between morphology of thallus and intensity of O2 uptake. The knowledge of the value of respiratory rate offers some explanation about the understanding of the level of development of metabolic activity in algal organisms in determined ecological conditions.