EN
Structure and topography of claustrum have been earlier described in Primates and in other mammals. Similar examinations have not been carried out on brains of Chinchilla lanigera so far. The aim of this paper was to study structure and topography of claustrum, analyse its shape, compare it with a shape of other animals especially rodents. Neurons forming this structure were analysed, morphometric analyses of a number of nervous cells in pars dorsalis and pars ventralis were made. Histological slides were stained with cresyl violet according to Klüver and Barrera’s method. Chinchilla’s claustrum resembles a shape of a sand glass, made up of pars dorsalis and pars ventralis. In pars dorsalis numerous oval and round, large and medium size neurons arranged in clusters were observed. Pars ventralis was characterized by less numerous round, small and medium cells scattered irregularly. The carried out morphometric analyses correlate with quantity analyses. Structure and topography of Chinchilla lanigera’s claustrum is similar to this nucleus’ form especially in rabbit.