Christian grave markers that were collected from the catacombs that line the via Appia. There are many catacombs because Christians, and Jews, buried their dead ones. They did not cremate the deceased, as did the Romans.
Lower left: doves and a chi rho symbol. Upper left: a dove with a wreath. Center: a fish spelled out with the Greek Icthius (= Jesus, Christ, Son of God, Savior and the chi rho symbol and dove. Upper right: the Good shepherd. Lower right: gifts being brought to the Virgin and Child.