ON THE WIND-POWERED NEBULA NGC-2359 AND THE WN-STAR HD-56925

We discuss two possible cases to explain the parabolic are in the nebula NGC 2359 as a bow shock structure. In case A, the progenitor of the WN star HD 56925 may have evolved along the sequence: O --> RSG --> WN, while moving supersonically with respect to the ISM. About 7x10(4) yr ago, the progenitor switched to the WN stage and began to blow a fast wind which drove a new bubble into the slow RSG wind, but some interstellar clumps might have been left within the bubble. At present, the spherical shock is intersecting with the bow shock in the east, forcing its way through the latter. It is shown that the radiation energy of the outer structure (i.e., bow shock shell) comes From the UV photons that escape from the inner bubble. In case B, the bow shock may be powered by another star and collide with the eastern molecular clouds. They are all located in the foreground of the spherical shell and HD 56925.