OCULAR-DOMINANCE COLUMNS
A single section through the 
dome-shaped cortex is made 
parallel to the surface. It cuts 
through layer 4 in a ring.

A reconstruction of many such 
rings from a series of sections--
the deeper the section, the 
bigger the ring--made by 
cutting out the rings and 
superimposing them. (Traces of 
the rings can be seen because it 
was difficult to get all the 
sections exposed and 
photographed equally, 
especially as I am strictly an 
amateur photographer.)

    Eye-dominance groupings of 
cells in the striate cortex were 
the first to be recognized, 
largely because they are rather 
coarse. Because we now have 
many methods for examining 
them, they are now the best-
known subdivision.