| Abstract | A single-dish H I survey of 91 Seyfert and Seyfertlike galaxies is reported. H I emission has been detected in 39 galaxies and H I absorption in two. The observed galaxies are located north of declination -19 degrees, and all but nine have recession velocities below 12,000 km/s. The redshifts obtained from the nuclear optical emission lines are systematically smaller than the systemic velocities derived from the H I emission line profiles, an effect which probably arises from a net outflow of gas in the narrow emission line regions. Seven cases of very gas-rich Seyferts with a hydrogen mass to blue luminosity ratio greater than 0.4 are observed; for the majority, this ratio does not differ from the values expected for a normal galaxy of the same morhological type. A large fraction of the Seyferts exhibit H I profiles different from the typical profiles of normally rotating spiral galaxies. |
