Harry Potter Marauder's Map Question?

On the Marauder's Map in Harry Potter and the Goblet of Fire, after Harry left the prefect's bathroom, he see's Barty Crouch on the map, but it isn't Barty Crouch, it's his son, Barty Crouch Jr as Professor Moody. Is this the glitch in the map? Or had Harry just miss read the map and didn't see the Jr. part?