• A cerebral biopsy specimen from a 4-year-old girl with a moderately advanced stage of the late infantile form of neuronal ceroid-lipofuscinosis was observed in routine cell and fiber stains and in Golgi and electronmicroscopic preparations. There was no evidence of neuronal degeneration or loss. Golgi impregnations identified a fusiform enlargement of proximal axon segments of most pyramidal neurons and some polymorphic neurons but not of other cortical neuronal classes. Typical curvilinear inclusions were found in all cells and appeared to be impacted within the dilated proximal axon segments of pyramidal neurons. The numbers of type II synapses on the axon hillock and dilated proximal axon segments of pyramidal neurons were much reduced, whereas type I synapses remained abundant in the neuropil.