  We investigate in detail the properties of oscillating instanton solutions
discussed recently in the literature. We find that the solutions with N nodes
contain exactly N homogeneous negative modes in their spectrum of linear
perturbations. The existence of extra negative modes for the N > 1 solutions
suggest that they are not final state physical objects resulting from
tunneling, but rather unstable intermediate thermal configurations. By
contrast, the single negative mode for the N = 1 instanton confirms its
interpretation as mediating the curved-space tunneling between vacua with equal
energy densities.
