  A novel finite element method for the approximation of Maxwell's equations
over hybrid two-dimensional grids is studied. The choice of appropriate basis
functions and numerical quadrature leads to diagonal mass matrices which allow
for efficient time integration by explicit methods. On purely rectangular
grids, the proposed schemes coincide with well-established FIT and FDTD
methods. Additional internal degrees of freedom introduced on triangles allow
for mass-lumping without the usual constraints on the shape of these elements.
A full error analysis of the method is developed and numerical tests are
presented for illustration.
