As I’ve visited various invitations stores and flipped through their gigantic books, the “within-the-ribbon” card kept popping up.
Since I had no clue what “Within-the-ribbon?” meant, I searched Crane's
Within-the-Ribbon Cards: Pews may be cordoned off with white ribbons or cords to indicate a special seating section. When this is done, small cards reading "Within-the-ribbon" are sent with the invitations to those guests who will be seated in that section. The guests then bring the cards to the ceremony, which enables the ushers to seat them in the appropriate section.
Who knew? Have you ever received a “within-the-ribbon” card?