ABSTRACTOne of the unsettled questions in meteoritics relates to the determination of the total number,N, of meteorites falling in such showers as those of Pultusk (Poland), Estherville (Iowa), and Holbrook (Arizona). The value ofNhas, for obvious reasons, not been determined by counting. Partial and unsystematic counts either have been accepted as giving the true value ofNor else have been corrected by arbitrarily assuming that some specified fraction ofNescaped enumeration. In the present paper, several simple criteria for estimating the population of a meteoritic shower are derived by use of the theory of probability. The formulas deduced for the determination ofNhave been tested with satisfactory results on man‐made meteoritic showers. By the use of one of the criteria, it is shown that, for the Holbrook shower,Nwas almost certainly of the order of 100,000, and hence that the population of the Pultusk shower, which seems to have been a larger one even than Holbrook, probably considerably exceeded this figure. The criteria developed may be employed in many other connection