ON THE POPULATION OF H-I DWARF GALAXIES

We report results from a 21 cm survey of fields in the Perseus-Pisces supercluster and a foreground void, which was designed to find gas-rich dwarf galaxies or optically faint H I clouds with masses M(HI) greater-than-or-similar-to 10(8) M.. We detected 16 objects in the supercluster, nine of them previously uncataloged. We found no objects in the void fields, an indication that H I dwarf galaxies follow the spatial structure defined by bright galaxies, although our results do not rule out a moderate "bias" between dwarfs and bright galaxies. The number of galaxies detected is smaller than expected from a simple extrapolation of the optical luminosity function. These data leave no room for a substantial population of H I dwarfs or gas-rich, low surface brightness giants that could have been missed by conventional, optical galaxy catalogs.