He was referring to one of the male figures in white, whose head was a portrait of Dr. Benjamin Hitz, the hospital's Chief Obstetrician. Hitz was a blindingly handsome man.  
"Lot of faces still to fill in," said the orderly. He meant that the faces of many of the figures in the mural were still blank. All blanks were to be filled with portraits of important people on either the hospital staff or from the Chicago Office of the Federal Bureau of Termination.
 
"Must be nice to be able to make pictures that look like something," said the orderly.
 
The painter's face curdled with scorn. "You think I'm proud of this daub?" he said. "You think this is my idea of what life really looks like?"
 
"What's your idea of what life looks like?" said the orderly.
 
The painter gestured at a foul dropcloth. "There's a good picture of it," he said. "Frame that, and you'll have a picture a damn sight more honest than this one."
 ............