Spinal cord white matter, stained with Luxol Blue (top) and H&E (bottom). All nuclei found in white matter belong to neuroglia (except for nuclei associated with vessels). Although not every nucleus can be confidently identified, a search usually uncovers typical nuclei of astrocytes (green arrows) and oligodendrocytes (red arrows). Myelinated axons are also evident (black arrows) against the neurokeratin background.