He turned and glanced casually...

a middle-aged man dressed in a brown sack suit, it was, sitting a little apart at a table by himself and watching their party intently.

At Amory's glance he smiled faintly.

Amory turned to Fred, who was just sitting down.
"Who's that pale fool watching us ?" he complained indignantly.
"Where ?" cried Sloane.

"We'll have him thrown out!" He rose to his feet and swayed back and forth, clinging to his chair.