  We present results of a morphological analysis of a small subset of the
Spitzer Wide-area InfraRed Extragalactic survey (SWIRE) galaxy population. The
analysis is based on public ACS data taken inside the SWIRE N1 field, which are
the deepest optical high-resolution imaging available within the SWIRE fields
as of today. Our reference sample includes 156 galaxies detected by both ACS
and SWIRE. Among the various galaxy morphologies, we disentangle two main
classes, spheroids (or bulge-dominated galaxies) and disk-dominated ones, for
which we compute the number counts as a function of flux. We then limit our
sample to objects with IRAC fluxes brighter than 10 microJy, estimated ~90%
completeness limit of the SWIRE catalogues, and compare the observed counts to
model predictions. We find that the observed counts of the spheroidal
population agree with the expectations of a hierarchical model while a
monolithic scenario predicts steeper counts. Both scenaria, however,
under-predict the number of late-type galaxies. These observations show that
the large majority (close to 80 per cent) of the 3.6 and 4.5 micron galaxy
population, even at these moderately faint fluxes, is dominated by spiral and
irregular galaxies or mergers.
