Limitations Imposed on Statistical Studies of Galactic Supernova Remnants by Observational Selection Effects

The selection effects that apply to the identification of Galactic supernova remnants are reviewed together with the limitations that they impose on statistical studies. Emphasis is given to problems with recent discussions of the number, birthrate, and distribution of remnants within the Galaxy. The distribution of high-surface-brightness remnants is concentrated in a nuclear disk that is even more well-defined than that noted by van den Bergh 1988a,b. Also presented, as an appendix, are revisions to the catalog of Galactic supernova remnants presented in Green 1988. The revised catalog contains 174 remnants.