  Quasi-toroidal oscillations in slowly rotating stars are examined in the
framework of general relativity. The oscillation frequency to first order of
the rotation rate is not a single value even for uniform rotation unlike the
Newtonian case. All the oscillation frequencies of the r-modes are purely
neutral and form a continuous spectrum limited to a certain range. The allowed
frequencies are determined by the resonance condition between the perturbation
and background mean flow. The resonant frequency varies with the radius
according to general relativistic dragging effect.
