Nervus opticus (400X) Nervus opticus. Image copyright: University of Oslo, CC BY-NC-ND 4.0. (Tissue stain: H+E). Magnify Labels Up (40X) Identify: groups of axons (nervous tissue) septa of connective tissue separating the groups of axons. These septa are actually part of the pia mater the subarachnoid space the pia mater Published February 13th 2022, updated February 23rd 2022. Share on Facebook Tweet Send email