Elliptical galaxies have hot X-ray emitting atmospheres but
practically no cold gas, so it came as a surprise that they are
often IRAS sources.  There are two likely explanations for the
origin and heating of the dust that emits this infrared
radiation.  The dust may be in a low-mass disk of neutral gas
near the center of the galaxy and is heated by starlight.
Alternatively, the dust is shed by stars during stellar evolution
and heated by collisions with the ambient hot X-ray emitting gas
or by starlight.  These different possibilities have distinctive
signatures in the extent and shape of infrared emission as well
as the presence or absence of the PAH bands.  We propose to
determine the origin and heating of the dust by obtaining CAM
images of 11 X-ray emitting elliptical galaxies.  By using
multiple narrow filters in the 5-17 micron range we will be able
to separate the PAH component as well as establish the shape and
extent of the emission.