From two or more couples circling clockwise: The call is "Birdie in the Cage and (from three to seven) hands around." Here the active lady steps into the center and the others circle around her. "Bird fly out and the crow hop in"--active lady rejoins the circle and the active man steps into the center as the others circle.
This definition is from The Handbook of Modern Square Dancing by Jay King.
It is provided here for informational and educational purposes only.