Mark, John, the author of the second Gospel, the son of Mary, Barnabas' sister, who ministered to Christ, and whose house in Jerusalem was a place of resort for the disciples of Christ after the resurrection; accompanied Paul and his uncle on their first missionary journey, afterwards accompanied Peter, who calls him “my son,” and to him it is thought he is indebted for his Gospel narrative; he is regarded as the founder of the Coptic Church, and his body is said to have been buried in Venice, of which he is the patron saint, and the cathedral of which is named St. Mark's after him; he is represented in Christian art as a man in the prime of life accompanied by a winged lion, with his Gospel in his left hand and a pen in his right.
Definition taken from The Nuttall Encyclopædia, edited by the Reverend James Wood (1907)
Mark, Gospel according to * Mark Antony