The absence of reliable and detailed data on internal migration is a problem that repeatedly confronts demographers and population geographers concerned with the dynamics of spatial populations. The first of the two short notes assembled in this paper describes a procedure for identifying and summarizing the persisting regularities that appear in empirical data on interregional migration. An application based on data for the Soviet Union illustrates the principal argument. 

The second note considers some of the geographical consequences of zero population growth in the Soviet Union. Specifically, attention is focused on the changes in age compositions and in regional shares of the urban and rural populations of the U.S.S.R. that might arise were fertility immediately to decline to replacement level.