  Using a variety of parameters of local galaxy density, we have examined the
effects of the environmental density on the presence of bar structures in
spiral galaxies of various morphological types. For an extensive sample of
nearby galaxies, listed in the ``Nearby Galaxies Catalogue'' (Tully, 1988a), we
have found that the spirals characterized by a high local density tend to be
barred if they are early-type and early-type if they are barred (at the
significance level of $\sim$3 sigma), confirming some earlier suggestion of low
statistical significance. This fact, which is observed substantially in
low-luminosity spirals, indicates that galaxy interactions can stimulate the
formation of bars, primarily in early-type, low-luminosity spirals. This is in
partial, qualitative agreement with the most recent relevant N-body
simulations. On the other hand, no significant density segregation is observed
between pure S-shaped (S(s)) spirals and spirals with inner rings (S(r)), which
are often associated with bars. {\it Subject headings:} galaxies: general ---
galaxies: structure --- galaxies: interactions --- galaxies: clustering
