We investigate the dependence of the galaxy infrared luminosity function (L
F) and the associated stellar mass function (SMF) on environment and spectr
al type using photometry from the Two Micron All Sky Survey and redshifts f
rom the Las Campanas Redshift Survey for galaxies brighter than M-J < -19 5 log h. In the field environment, the LFs of galaxies with emission lines
have much steeper faint-end slopes (<alpha>(J) = -1.39) than those of gala
xies without emission lines (alpha (J) = -0.59). In the cluster environment
, however, even the non-emission-line galaxies have a steep faint-end LF (a
lpha (J) = -1.22). There is also a significant (95%) difference between the
overall cluster and field LFs, Delta alpha (J) = -0.34 and DeltaM(J)* = -0
.54. All these variations are more pronounced in the SMFs, which we compute
by relating the strength of the 4000 Angstrom break in the optical spectra
to a stellar mass-to-light ratio.