  We study the effects of an elastic crust on the oscillation spectrum of
superfluid neutron stars. Within the two fluid formalism, we consider Newtonian
stellar models that include the relevant constituents of a mature neutron
stars. The core is formed by a mixture of superfluid neutrons and a
conglomerate of charged particles, while the inner crust is described by a
lattice of nuclei permeated by superfluid neutrons. We linearise the Poisson
and the conservation equations of nonrotating superfluid stars and study the
effects of elasticity, entrainment and composition stratification on the shear
and acoustic modes. In both the core and the crust, the entrainment is derived
from recent results for the nucleon effective mass. Solving the perturbation
equations as an eigenvalue problem, we find that the presence of superfluid
neutrons in the crust and their large effective mass may have significant
impact on the star's oscillation spectrum.
