The collection contains permanent histological preparations of the brain of several species of cartilaginous and bony fishes stained using classical neurohistological techniques: Nissl staining and Golgi impregnation. The preparations of each species (several dozens of microscope slides) are stored in separate numbered slide boxes in a special storage cabinet located at the Department of Cytology and Histology of the Saint-Petersburg State University. Each slide is labelled with all essential identifying information. This collection is intended for those students, scientists and teachers who want to learn more about the architecture of the brain and especially its principal region, telencephalon, in several representatives of fishes. The collection is a visual study guide for the teaching courses on zoology, physiology, higher functions of the nervous system, histology, cytology, evolutionary theory, etc., taught at the departments and schools of biological sciences in the universities.