  The Tully-Fisher (TF) or the luminosity line-width relations of the galaxies
in the Eridanus group are constructed using the HI rotation curves and the
luminosities in the optical and in the near-infrared bands. The slopes of the
TF relations (absolute magnitude vs log2V_{flat}) are -8.6\pm1.1, -10.0\pm1.5,
-10.7\pm2.1, and -9.7\pm1.3 in the R, J, H, and K bands respectively for
galaxies having flat HI rotation curves. These values of the slopes are
consistent with those obtained from studies of other groups and clusters. The
scatter in the TF relations is in the range 0.5 - 1.1 mag in different bands.
This scatter is considerably larger compared to those observed in other groups
and clusters. It is suggested that the larger scatter in the TF relations for
the Eridanus group is related to the loose structure of the group. If the TF
relations are constructed using the baryonic mass (stellar + HI + Helium mass)
instead of the stellar luminosity, nearly identical slopes are obtained in the
R and in the near-infrared bands. The baryonic TF (baryonic mass vs
log2V_{flat}) slope is in the range 3.5 - 4.1.
