  There are two different methods to describe membrane (string) fluids, which
use different field content. The relation between the methods is clarified by
construction of combined method. Dirac membrane field appears naturally in new
approach. It provides a possibility to consider new aspects of
electrodynamics-type theories with electric and magnetic sources. The membrane
fluid models automatically prohibit simulatenos existence of electric and
magnetic currents. Possible applications to the dark energy problem are
mentioned.
