  We present the first interferometric CO observations of the barred late-type
galaxy UGC2855 and its companion UGC2866. UGC2855 is shown to belong to the
rare class of galaxies with a long (~ 8kpc) continuous molecular bar. The
velocity field along the bar is dominated by solid-body rotation and shows few
perturbations. This, together with an almost constant and low ^12CO/^13CO line
intensity ratio along the bar and in the center as well as only weak H alpha
emission, indicate that the gas in the bar is not subjected to strong shocks,
but surprisingly quiescent. In the central 3'', a high velocity feature
consisting of a number of Giant Molecular Associations, is identified. We
discuss possible scenarios of the nature of this structure in connection with
the question of the presence of an Inner Lindblad Resonance (ILR) in the bar.
We suggest that the bar of UGC2855 is a young object, possibly has no ILR, and
that the mass concentration toward the center of the galaxy is just beginning.
In contrast, the companion UGC2866 experiences a strong starburst. We compare
the properties of the gas in the bar of UGC2855 to those we find in NGC7479.
Despite superficial parallels, the two bars are very dissimilar objects in
terms of ^12CO/^13CO line ratio, velocity field and H alpha activity. NGC7479
exhibits starburst characteristics, while we argue that UGC2855 is in a
pre-burst stage.
