  We present results from two mid-infrared imaging programs of ultraluminous
infrared galaxies (ULIRGs) and fine-structure elliptical galaxies. The former
are known to nearly all be recent mergers between two gas-rich spiral galaxies,
while the latter are also believed to be even more aged merger remnants. An
examination of these two classes of objects, which may represent different
stages of the same putative merger sequence, should reveal similarities in the
distribution of their stellar populations and dust content consistent with that
expected for time-evolution of the merger. The data reveal for the first time
extended dust emission in the ULIRG galaxy bodies and along their tidal
features. However, contrary to expectation, we find that the vast majority of
the fine-structure elliptical galaxies lack such structured emission. This
likely results from the optical selection of the elliptical sample, resulting
in a population that reflects the IR-activity (or lack thereof) of optically
selected interacting galaxies. Alternately, this may reflect an evolutionary
process in the distribution of the dust content of the galaxy bodies.
