The divisions of retinal cells in a developing Urodelan Amphibian (Triturns cristatus carnifex, Laur.) are located in the outer layer of the margin of the pars optica retinae (anterior margin). The mitotic ratio of anterior margin during the eye growth is constant, except for a fall at the beginning of the larval period, which occurs also in other sites of the nervous system. The morphological observations and the mitotic ratio during the Urodelan growth show that the anterior margin is the meristematic tissue which supplies the growing retina with new cells. The different rate of cell divisions and the regular differentiation of new nerve cells during the growing retina induce the variations both on the number of the indifferentiated cells and on the length of the anterior margin.