Nuclear Sizes in Rana Mesonephroi

Abstract

When Jacobj (1925) devised the now classical caryometric method there was opened up for the cytologist a whole new field in population dynamics. Jacobj demonstrated that for any given organ the nuclear population showed considerable variation in size from one individual nucleus to another. By plotting frequency distribution curves of nuclear volumes he obtained evidence to show that the volumes increased discontinuously according to a logical pattern. The peaks of the curve corresponded to nuclear volumes which when arranged in series gave the geometric progression 1 : 2 : 4 : 8. Nuclear class series have since been described for a wide range of both invertebrate and vertebrate tissues.Caryometry has been used extensively in investigations of ploidy, of endomitotic growth, and of the interphasic growth of nuclei in a dividing tissue. The concept