This portal wing is topped by a flat triangular tympanum and has tall rectangular windows and oculi in the panels below the beams.
Its anterior surface, transparent and more curved, is known as the cornea of the bulbus oculi.
However, the bulbus oculi is not completely spherical.
This is because the different branches innervate the frontalis muscle, orbicularis oculi and oris muscles, lip elevators and depressors, and the platysma.
The orbicularis oculi muscles are often examined in patients with facial paralysis.
The west front has two lancet windows, two oculi and a double door.
Its two characteristic domes cover both spans of the nave, while a series of oculi provide the cathedral's lighting.
Four such muscles that were activated were the orbicularis oculi, zygomaticus, the corrugator, and levator.
