An ontogenetic study of the central nervous system is an important tool for the under- standing of its morphological and morpho-functional relations. Numerous qualitative results on the ontogenesis of the visual system can be found in the literature, but there are only very few quantitative results fulfilling the following parameters: (1) samples of sufficient size; (2) measurements considering results of stereology; (3) evaluation and interpretation performed with sound biomathematical methods; (4) quantitative of the shrinkage caused by the histological technic. The first three results...