[Discovery of the nature of the process of fertilization and of the role of nuclear structures in this process (on the centenary of the discovery)].

The history of the discovery by O. Hertwig (1875-1878) of the very nature of fertilization--the fusion of the egg's and spermatozoon's nuclei--is presented. In result, the principle of continuity of the nuclear structures in embryonic development was proclaimed. It is noticed that the correct understanding of such phenomena as maturation of the egg, meiosis and fertilization as well the role played by the nuclear structures in these processes was achieved not at once but gradually due to joint efforts of the number of scientists (E. van Beneden, O. Bütschli, H. Fol, W. Flemming and others).