Fig. 4.8. Two empty myelin sheaths in layer 4 of the primary visual cortex of a 12 year old monkey. There are the remains of some axoplasm, including the profile of a mitochondrion, inside the sheath of the larger of the two nerve fibers and as in the previous example the lamellae of this sheath are split. The axon within the smaller myelin sheath has completely degenerated.
