  We study properties of excited states of an elongated Fermi superfluid along
the BEC-BCS crossover including the unitarity limit. Analytic expressions for
the sound velocity in an inhomogeneous as well as homogeneous Fermi superfluid
along the crossover are obtained on the basis of the hydrodynamic theory. The
complete excitation spectrum of axial quasiparticles with various discrete
radial nodes are presented. We discuss the feasibility of measuring the sound
velocity and the multibranch Bogoliubov spectrum experimentally.
