For a projective variety V in P^n over a field of characteristic zero, with
homogeneous ideal I in A = k[x0,x1,...,xn], we consider the local cohomology
modules H^i_I(A). These have a structure of holonomic D-module over A, and we
investigate their filtration by simple D-modules. In case V is nonsingular, we
can describe completely these simple components in terms of the Betti numbers
of V.