  We present luminosity functions for galaxies in loose groups in the Las
Campanas Redshift Survey, differentiated by their environment (defined by the
line-of-sight velocity dispersion sigma of the host groups) and also by their
spectral type (emission or non-emission, defined by the equivalent width of the
3727-Angstrom [OII] line).
  We find systematic variations in the Schechter parameters alpha and M* for
non-emission line galaxies over a range of 0 < sigma < 800 km/s. Alpha varies
from 0.20 to -0.91, indicating an increase in the steepness of the faint end
slope with increasing sigma. The accompanying variation in M* appears to be
accounted for by the intrinsic correlation with alpha and does not indicate a
significant physical variation in the bright end of the luminosity function.
For emission line galaxies, we find no significant systematic variation of the
luminosity function with the environment. Our results show that emission and
non-emission galaxies generally occupy two distinct regions in the alpha-M*
parameter space. From our luminosity functions, we derive the number ratios of
emission to non-emission galaxies as a function of environment and absolute
magnitude, showing that the relative abundance of non-emission line galaxies
generally increases for all magnitudes -23 < M_R < -17.5 towards high-sigma
environments, from ~80% to >90% at M_R = -22 and from ~10% to >50% at M_R = -18
(H_0 = 100 km s^{-1} Mpc^{-1} and q_0 = 0.5).
