From a squared set: Heads and sides retain identity throughout. Heads Crosstrail thru and separate to loop around and Star Thru to face in at the side position. As soon as the center is clear, the sides Crosstrail Thru and loop around to Star Thru at the head position. Repeat three times to get everyone home. Couples move into the center to Crosstrail Thru as soon as the other two couples have cleared the center.
This definition is from The Handbook of Modern Square Dancing by Jay King.
It is provided here for informational and educational purposes only.