  For Hill's equations with matrix valued periodic potential, we discuss
relations between the Morse index, counting the number of unstable eigenvalues,
and the Maslov index, counting the number of signed intersections of a path in
the space of Lagrangian planes with a fixed plane. We adapt to the one
dimensional periodic setting the strategy of a recent paper by J. Deng and C.
Jones relating the Morse and Maslov indices for multidimensional elliptic
eigenvalue problems.
