We have realized new systems which consist of a periodic packing of a bidimensional magnetic liquid alternate with nonmagnetic fluid. These ‘‘ferrosmectic’’ phases are obtained by incorporating solid magnetic particles in lyotropic lamellar systems. Their existence has been proved by their optical properties and their anisotropic behavior in applied magnetic field. This new system offers a large domain of investigation, both as a special bidimensional ferrofluid, and as an example—the first to our knowledge—of the compatibility between solid particles and structured liquids.