A listing is given of all supernovae discovered between 1989 January 1 and 1993 April 1. The data show no evidence for a significant dependence of the discovery probability of supernovae on parent galaxy inclination to the line of sight. If no inclination corrections need to be applied, then the supernova rates in spirals are only about half as large as previously believed. The mean linear separation of supernovae of type II (SNe II) from the center of their parent galaxy increases with increasing distance (Shaw effect). The Shaw effect appears less evident, or absent, for (more luminous) supernovae of type Ia. The data are consistent with, but do not prove, the hypothesis that (presumably reddened) SNe II are more likely to be discovered in the red than in the blue. Due to intensive surveillance, most bright SNe Ia tend to be found before maximum, whereas the majority of faint SNe Ia are discovered after maximum light.