mishaps in neuroanatomical nomenclature

If it is true, as has been said, that all of science is either mathematics or stamp collecting, then the question must sometimes arise, how are we to tell the two apart?

One way is mistakes. Because mistakes, such as the inverted jenny, are prized by stamp collectors, but stamped out (sorry!) by mathematicians.

Here are my favorite mistakes in neuroanatomical nomenclature:

• The optic nerve is not a nerve. Because by definition, "nerves" exist only outside the skull. How about optic tract?
• The basal ganglia are not ganglia, and are not strictly basal. Because by definition, ganglia exist only outside the skull. You could call 'em nuclei.
• "Pons" means "bridge" but the pons does not bridge the two cerebellar hemispheres; it only appears to.
• The substantia innominata (literally stuff with no name) has got a name.

Okay, maybe the last one isn't so much wrong as recursive or self-referential.