  We have carried out high-resolution (~3') HI and CO line observations of
GW46.4+5.5 and analyzed available IR and radio emission survey data. GW46.4+5.5
appears as a long filamentary structure extending vertically from the Galactic
plane in both far-IR and radio continuum maps. The I_60/I_100 ratio in the worm
is estimated to be 0.29+-0.05, which is significantly higher than the value for
the solar neighborhood. The high ratio is consistent with a hypothesis that the
dusts in the worms have been processed by interstellar shocks. The radio
continuum emission from the worm has a spectral index of -0.47 and does not
correlate with I_60. Thus, most of the radio continuum emission is likely to be
nonthermal. Our HI observations show that the HI gas is clumpy. We detected two
molecular clouds associated with the HI peaks. The molecular clouds do not
appear to be gravitationally bound. Using the Leiden-Dwingeloo HI data, we
identify an expanding HI supershell associated with GW46.4+5.5, which is a size
of 14^o*22^o. The supershell appears between 18 and 40 km/s, and decreases
slowly in size as the velocity increases. An averaged l-v diagram reveals that
the supershell has a central velocity of ~18 km/s (d_kin=1.4 kpc) and an
expansion velocity of ~15 km/s. The structure is also visible in adio continuum
maps. The observed molecular clouds might have condensed out of
shock-compressed gas in GW46.4+5.5 because they are closely associated with the
HI gas in velocity as well as in position. Their altitudes are 80 and 100 pc,
respectively, and their physical properties are very similar to those of the
high-altitude clouds. Our results suggest that at least some of the
high-altitude clouds might have formed in Galactic worms (or HI supershells).
