Mortimer Icobod Marker or Mortimer the Marker was the name of the writing utensil that Bill Cosby used in Picture Pages. It made a dee-dee-dee-dee-dee sound when he wrote. I think we all wanted a marker that Bill Cosby used in Picture Pages, but I'm not sure one was available. You did get to follow along with the tv show in the Picture Pages book, even though you had to use your own pencil/pen/crayon.