NEW H-I OBSERVATIONS OF THE PROTOTYPE POLAR RING GALAXY NGC-4650A

New, high resolution observations of the H I emission line and 20-cm c ontinuum at the Australia Telescope Compact Array (ATCA) for the proto type polar ring galaxy NGC 4650A are presented. We show the presence o f a far more extended H I distribution than previously observed with t he VLA, and a very regular velocity field out to a distance of similar to 50 kpc, The combined analysis of the HI data with optical and near -infrared images argues against previous warp models used to describe the dynamics of this object. A comparison between the high resolution HI images and a new B-band image obtained at the ESO NTT further weake ns the interpretation of the optical morphology via warp geometries, T he presence of two spiral arms stretching out in the polar disk seems to represent the most likely explanation for the observed morphology a nd kinematics. (C) 1997 American Astronomical Society.