Did St. Christopher really have a dog's head?

In Eastern Orthodox icons, Saint Christopher is sometimes represented with the head of a dog.

The background to the dog-headed Christopher is laid in the reign of the Emperor Diocletian, when a man named Reprebus, Rebrebus or Reprobus was captured in combat against tribes dwelling to the west of Egypt in Cyrenaica. To the unit of soldiers, according to the hagiographic narrative, was assigned the name numerus Marmaritarum or "Unit of the Marmaritae", which suggests an otherwise-unidentified "Marmaritae" (perhaps the same as the Marmaricae Berber tribe of Cyrenaica).

He was reported to be of enormous size, with the head of a dog instead of a man, apparently a characteristic of the Marmaritae. This Byzantine depiction of St. Christopher as dog-headed resulted from their misinterpretation of the Latin term Cananeus (Canaanite) to read canineus (canine).

According to the medieval Irish Passion of St. Christopher, "This Christopher was one of the Dog-heads, a race that had the heads of dogs and ate human flesh."  It was commonly accepted at the time that there were several types of races, the Cynocephalus, or dog headed people, being one of many believed to populate the world.

In Eastern icons, Saint Christopher is sometimes represented with the head of a dog